Globalstar USA FAU200RA Globalstar Fixed Access Unit with Remote Antenna User Manual Front

Globalstar USA, LLC Globalstar Fixed Access Unit with Remote Antenna Front

User Manual

Description of the Globalstar System GS-TR-94-0001Revision EPage iDescriptionof theGlobalstar SystemDecember 07, 2000
Description of the Globalstar System GS-TR-94-0001Revision EPage iiDOCUMENT REVISION HISTORY1Revision Date of Issue ScopeA6/3/94 Incorporated QUALCOMM CommentsB12/20/94 Updated after SRR/PDR ReviewsC8/10/95 Updated after the HLDR ReviewsD2/24/97 Update to incorporate design changesE12/07/00 Added Photographs & Revised Services23Abstract456This document is written to introduce new people to Globalstar. It7attempts to provide a general overview of the system and to provide some8information on the design of the system. It also attempts to define how9Globalstar is envisioned to operate. As such, this is primarily tutorial in10nature. In the interests of brevity, simplifications are made in the material11herein. There is no attempt to be totally complete or comprehensive for all12cases.1314This document should not be interpreted as a binding specification. It does15not contain requirements that should be interpreted as either complete or16binding. Globalstar is an evolving system. This document will be updated17as the design of the system progresses. When each revision is issued there18is an attempt to represent the current thinking on the system.1920For binding specifications and requirements please consult the released21requirements documents and the released design information.222324Globalstar, L.P.3200 Zanker RoadSan Jose, Ca. 95164-0670Copyright © 1997 Globalstar, L.P. All rights reserved. Printed in the United States of America.
Description of the Globalstar System GS-TR-94-0001Revision EiiiContents11. SERVICES OFFERED 1-121.1 Service Types..........................................................................................................1-131.2 IS-41 Services .........................................................................................................1-141.3 GSM Services..........................................................................................................1-851.4 Globalstar Specific Services and Quality ........................................................1-1561.5 External Network Supported Services ............................................................1-1772. SYSTEM SEGMENT DESCRIPTIONS 2-182.1 Globalstar System..................................................................................................2-192.2 User Terminal.........................................................................................................2-3102.2.1 Hand Held and Mobile Units.........................................................................2-3112.2.2 Fixed Terminals...............................................................................................2-7122.3 Gateway....................................................................................................................2-8132.4 User Terminal and Gateway Interaction........................................................2-12142.5 Globalstar Control Centers................................................................................2-13152.5.1 Ground Operations Control Center............................................................2-14162.5.2 Satellite Operations Control Center..........................................................2-17172.5.3 Globalstar Business Office ...........................................................................2-19182.6 Globalstar Satellite..............................................................................................2-20193. FREQUENCIES AND COVERAGE ANALYSIS 3-1203.1 Frequency Plans....................................................................................................3-1213.2 Satellite Antenna Beam Configuration............................................................3-2223.3 Earth Surface Coverage.......................................................................................3-7233.4 Position Determination.......................................................................................3-10243.5 Channel Characteristics.....................................................................................3-12253.6 Link Analysis........................................................................................................3-14264. CODE DIVISION MULTIPLE ACCESS (CDMA) 4-1274.1 Introduction ............................................................................................................4-1284.2 Diversity Combining.............................................................................................4-2294.3 Fade Mitigation......................................................................................................4-230
Description of the Globalstar System GS-TR-94-0001Revision Eiv4.4 Acquisition...............................................................................................................4-314.5 Forward CDMA Channel .....................................................................................4-524.6 Return Link CDMA Channel............................................................................4-1034.7 CDMA End to End Performance ......................................................................4-1245. TERRESTRIAL INTERFACE 5-155.1 Telecommunication Network Interface.............................................................5-165.2 Registration Process..............................................................................................5-475.3 Authentication Process.........................................................................................5-785.4 GSM - A Interface in Globalstar .......................................................................5-1096. CALL PROCESSING 6-1106.1 Call Processing between Globalstar and PLMN .............................................6-1116.2 TIA and ETSI Call Flow Examples ...................................................................6-51213
Description of the Globalstar System GS-TR-94-0001Revision EvFigures1Figure 2-1 Globalstar System Integrates with Terrestrial Network........................ 2-12Figure 2-2 Globalstar Constellation Serves Temperate Areas.................................. 2-23Figure 2-3 Typical Hand Held User Terminal ............................................................. 2-34Figure 2-4 Globalstar User Terminal Block Diagram................................................. 2-55Figure 2-5 User Terminal Startup Scenario within Globalstar ................................. 2-66Figure 2-6 Typical Fixed Terminal Application........................................................... 2-77Figure 2-7 Typical Gateway Installation....................................................................... 2-88Figure 2-8 Gateway Simplified Block Diagram............................................................ 2-99Figure 2-9 Globalstar Control Center ......................................................................... 2-1310Figure 2-10 Ground Segment Support for Communications.................................... 2-1411Figure 2-11 GOCC Simplified Block Diagram............................................................ 2-1512Figure 2-12 Ground Equipment Support for T&C Functions................................... 2-1713Figure 2-13 Spacecraft Bus Characteristics - Highly Autonomous......................... 2-2014Figure 2-14 Communications Payload Pictorial......................................................... 2-2115Figure 2-15 Communications Payload Simplified Block........................................... 2-2116Figure 2-16 Satellite T&C - Compatible with Communications .............................. 2-2217Figure 3-1 Frequency Plan - Emphasizes Conservation of Spectrum....................... 3-118Figure 3-2 S - Band Beams.............................................................................................. 3-219Figure 3-3 L- Band Beams............................................................................................... 3-320Figure 3-4 L - Band Channel Frequencies .................................................................... 3-421Figure 3-5 S - Band Channel Frequencies..................................................................... 3-422Figure 3-6 Full Earth Coverage-Except Polar Regions............................................... 3-723Figure 3-7 Enhanced Coverage for Temperate Regions ............................................. 3-824Figure 3-8 Orbital Parameters for Globalstar Satellites............................................ 3-925Figure 3-9 Channel Characteristics Considerations................................................. 3-1226Figure 4-1 Acquisition Search Space ............................................................................. 4-327Figure 4-2 Acquisition Time as a function of Latitude................................................ 4-428Figure 4-3 Forward CDMA Channel Transmitted by a Gateway.............................. 4-529Figure 4-4 Forward Link Pilot, Sync and Paging Channel......................................... 4-630Figure 4-5 Forward Link Traffic Channel - Rate Set 1 ............................................... 4-731Figure 4-6 Forward Link Traffic Channel - Rate Set 2 ............................................... 4-832Figure 4-7 Forward Link Modulation and Spreading ................................................. 4-933Figure 4-8. Reverse CDMA Channels Received at a Gateway................................. 4-1034Figure 4-9 Return Link Access Channel ..................................................................... 4-1135
Description of the Globalstar System GS-TR-94-0001Revision EviFigure 4-10 Return Link Traffic Channel ................................................................... 4-121Figure 4-11 Forward Link Delay Budget.................................................................... 4-132Figure 4-12 Reverse Link Delay Budget..................................................................... 4-133Figure 4-13 Power Control Simplified Diagram ........................................................ 4-144Figure 4-14 Acquisition Time as a function of Eb/No ................................................ 4-155Figure 5-1 Gateway Architecture................................................................................... 5-16Figure 5-2 Gateway Connections to the PSTN - Flexible Interface .......................... 5-37Figure 5-3 Registration of a U.S. based User with an IS-41 HLR.............................. 5-48Figure 5-4 Registration of a European User in a GSM HLR...................................... 5-59Figure 5-5 Registration of a U.S. User in a GSM Environment................................. 5-610Figure 5-6 Registration of a European User in an IS-41 Environment..................... 5-711Figure 5-7 Authentication for a GSM User in IS-41 System....................................... 5-912Figure 5-8 GSM DTAP on Mobile Terminated Call................................................... 5-1013Figure 5-9 GSM DTAP on Mobile Originated Call .................................................... 5-1114Figure 6-1 Mobile Originated Call................................................................................. 6-115Figure 6-2 Roaming Call Delivery - Successful............................................................ 6-216Figure 6-3 Roaming Call Delivery - Subscriber Busy.................................................. 6-317Figure 6-4 Simple Call Flow, User Terminal Origination Example Using Service18Option 1 (TIA Call Control Procedures) .................................................. 6-619Figure 6-5 Simple Call Flow, User Terminal Origination Example Using Service20Option 1 (ETSI Call Control Procedures) (Part 2 of 2)........................... 6-721Figure 6-6. Simple Call Flow, User Terminal Termination Example Using Service22Option 1 (TIA Call Control Procedures) .................................................. 6-823Figure 6-7 Simple Call Flow, User Terminal Termination Example Using Service24Option 1 (ETSI Call Control Procedures) (Part 2 of 2)........................... 6-925Figure 6-8. Simple Call Flow, User Terminal Initiated Call Disconnect Example26(TIA Call Control Procedures)................................................................. 6-1027Figure 6-9 Simple Call Flow, User Terminal Initiated Call Disconnect Example28(ETSI Call Control Procedure) (Part 2 of 2)........................................... 6-1029Figure 6-10. Simple Call Flow, Gateway Initiated Call Disconnect Example (TIA30Call Control Procedures).......................................................................... 6-1131Figure 6-11 Simple Call Flow, Gateway Initiated Call Disconnect Example (ETSI32Call Control Procedure) (Part 2 of 2)...................................................... 6-1233Figure 6-12. Simple Call Flow, Three-Party Calling Example (TIA Call Control34Procedures) ................................................................................................ 6-1335Figure 6-13. Simple Call Flow, Call-Waiting Example (TIA Call Control36Procedures) ................................................................................................ 6-1437Figure 6-14. Call Processing During Soft Handoff.................................................... 6-1538Figure 6-15. Call Processing During Sequential Soft Handoff................................ 6-1639Figure 6-16 Call Processing During Sequential Soft Handoff (Part 2 of 2) ............ 6-174041
Description of the Globalstar System GS-TR-94-0001Revision EviiTables1Table 1-1 Teleservices....................................................................................................1-12Table 1-2 Basic Bearer Services ..................................................................................1-23Table 1-3 IS-53 Call Number Presentation...............................................................1-24Table 1-4 IS-53 Call Forwarding.................................................................................1-35Table 1-5 IS-53 Call Delivery.......................................................................................1-46Table 1-6 Short Message Services...............................................................................1-47Table 1-7 Miscellaneous Services................................................................................1-58Table 1-8 Future IS-41 C Services..............................................................................1-69Table 1-9 Bearer Service - Full Duplex Asynchronous Data.................................1-810Table 1-10 Bearer Service - Full Duplex Synchronous Data.................................1-911Table 1-11 Bearer Service - PAD Asynchronous Data............................................1-912Table 1-12 Bearer Service - Packet Synchronous.................................................1-1013Table 1-13 Teleservices Speech..................................................................................1-1014Table 1-14 Teleservices - Short Message Service...................................................1-1015Table 1-15 Teleservices - Facsimile Transmission................................................1-1216Table 1-16 Supplementary Services - Line Identification....................................1-1217Table 1-17 Supplementary Services - Call Forwarding.......................................1-1318Table 1-18 Supplementary Services - Call Waiting & Call Hold........................1-1319Table 1-19 Supplementary Services - Closed User Group....................................1-1320Table 1-20 Supplementary Services - Advice of Charge.......................................1-1321Table 1-21 Supplementary Services - Call Barring...............................................1-1422Table 1-22 Supplementary Services - Multiparty Services..................................1-1423Table 1-23 External Network - Value Added Services..........................................1-1724Table 2-1 Production User Terminals ........................................................................2-325Table 3-1 Satellite C-Band to S-Band ........................................................................3-526Table 3-2 Satellite L-Band to C-Band........................................................................3-527Table 3-3 Satellite Telemetry & Command Frequencies.......................................3-628Table 3-4 Worst Case Doppler......................................................................................3-629Table 3-5 Forward Link C-Band - Case 1 - Detailed Budget...............................3-1430Table 3-6 Forward Link S-Band - Case 1 - Detailed Budget................................3-1531Table 3-7 Forward Link - Case 2 - Link Blockage..................................................3-1632
Description of the Globalstar System GS-TR-94-0001Revision EviiiTable 3-8 Forward Link - Case 3 - Rare Two Link Fade.......................................3-161Table 3-9 Return Link L-Band - Case 1 - Detailed Budget..................................3-172Table 3-10 Return Link C-Band - Case 1 - Detailed Budget...............................3-183Table 3-11 Return Link - Case 2 - Link Blockage..................................................3-184Table 3-12 Return Link - Case 3 - Rare Two Link Fade.......................................3-195Table 4-1 Vocoder and Channel Rates....................................................................4-1467
Description of the Globalstar System GS-TR-94-0001Revision EixThis page intentionally left blank.12345678
Description of the Globalstar System GS-TR-94-0001Revision E1-11. SERVICES OFFERED11.1 Service Types2Four types of communications services are supported by Globalstar depending on the environment in3which they operate (1) IS-41 Services, (2) GSM Services, (3) Globalstar Specific Services and (4)4Network Value Added Services.51.2 IS-41 Services6The following IS-41-based services are supported directly by the gateway. The IS 41 switch is in the7Gateway. The IS-41 C teleservices are listed in Table 1-1.8Table 1-1 Teleservices9Service Option DescriptionTelephony (circuit speech) Variable rate vocoded speech. – Comparable or better than IS-96A.Emergency Services (911) Globalstar emergency calls are routed to a single LAC directorynumber for further processing. Although the Gatewayretrieves position location data of the calling subscriber,position data is not provided to the Emergency Service Center.Automatic Facsimile Group III Normal Group III FAX – Digital PC Only - (Future)Lawful Intercept GS complies with the laws in the areas where they operate. Inthe U.S.A, this is call content and call associated data per DOJJ-STD-25 with minor exceptions.DTMF Support Dual Tone Multi Frequency. Used for voice Message Retrievaletc. Signal via GAI. Generated in GW or UT.10The IS-41 switch within the Gateway does not perform routing to sub-tier emergency numbers. The11Gateway can be configured to support multiple Location Area Codes (LAC). A different emergency12number can be assigned to each LAC.13
Description of the Globalstar System GS-TR-94-0001Revision E1-2Basic bearer services are listed in Table 1-2.1Table 1-2 Basic Bearer Services2Service Option Description2.4 Kb/s: DCA, (ADS) (Future)4.8 Kb/s: DCA, (ADS) (Future)9.6 Kb/s: DCA, (ADS) (Future)3Data Requires Flow Control: The Globalstar Air Interface (GAI) and the Gateway support packet4data. Because there is overhead in the GAI, external flow control is required to offer a 9.6 Kb/s service.5End to end peak throughput of the Globalstar link will be on the order of 7.2 Kb/s.6The initial offering (near future – 1.5 D2) of Async Data will be Mobile Originated (MO) only. Mobile7Terminated (MT) will require modifications to the HLR (future). Connecting the call will require about 58seconds. This is then followed with a variable time to train the modem.9IS-53 Supplementary Services supported by the Gateway are listed in Table 1-3.10Table 1-3 IS-53 Call Number Presentation11IS-53 Supplementary Services - Call Number PresentationService Option DescriptionCalling number identification presentation(CNIP)CNIP provides the number identification of the calling party tothe called subscriber. One or two numbers may be presented toidentify the calling party.Calling number identification restriction (CNIR) CNIR restricts presentation of that subscriber’s calling numberidentification (CNI) to the called party.12
Description of the Globalstar System GS-TR-94-0001Revision E1-3Table 1-4 lists some of the IS-53 call forwarding features.1Table 1-4 IS-53 Call Forwarding2IS-53 Supplementary Services - Call ForwardingService Option DescriptionCall forwarding unconditional (CFU) CFU permits a called subscriber to send incoming callsaddressed to the called subscriber’s directory number toanother directory number or to the called subscriber’sdesignated voice mail box. If this feature is activated, calls areforwarded regardless of the condition of the termination.Call forwarding default (CFD) CFD permits a called subscriber to send incoming callsaddressed to the called subscriber’s directory number to thesubscriber’s voice mail box or to another directory numberwhen the subscriber is engaged in a call, does not respond topaging, does not answer the call within a specified period afterbeing alerted or is otherwise inaccessible.Call Forwarding - Busy (CFB) CFB permits a called subscriber to have the system sendincoming calls addressed to the called subscriber’s directorynumber to another directory number or to the calledsubscriber’s designated voice mail box when the subscriber isengaged in a call or service.Call Forwarding - No Answer (CFNA) CFNA permits a called subscriber to have the system sendincoming calls addressed to the called subscriber’s directorynumber to another directory number or to the calledsubscriber’s designated voice mail box when the subscriberfails to answer or is otherwise inaccessible. CFNA does notapply when the subscriber is considered to be busy.
Description of the Globalstar System GS-TR-94-0001Revision E1-4Table 1-5 lists some of the IS-53 Call Delivery features.1Table 1-5 IS-53 Call Delivery2IS-53 Supplementary Services - Call Delivery FeaturesService Option Description3-way calling (3WC) 3WC provide the subscriber the capability of adding a thirdparty to an established two-party call, so that all three partiesmay communicate in a three-way call. Calling party initiated.Do not disturb (DND) DND prevents a called subscriber from receiving calls. Whenthis feature is active, no incoming calls will be offered to thesubscriber. DND also blocks other alerting, such as CFUreminder alerting and message waiting notification alerting.DND also makes the subscriber inaccessible for call delivery.DND does not impact a subscriber’s ability to originate calls.Call transfer (CT) CT enables the subscriber to transfer a call that is already inprocess to a third party. The call to be transferred may be anincoming or outgoing call. While CT is invoked, CT impactsthe subscriber’s ability to receive calls. After CT is finished orwhen CT is not invoked, CT does not impact a subscriber’sability to originate calls or to receive calls.Call delivery (CD) CD permits a subscriber to receive calls to his or her directorynumber while roaming.Call waiting (CW) CW provides notification to a controlling subscriber of anincoming call while the subscriber is in the 2-way state.Subsequently, the controlling subscriber can either answer orignore the incoming call. If the controlling subscriber answersthe second call, he or she may alternate between the two calls.Lawful Intercept Implications: The IS-53 Call Delivery services are coded and operational in the3present software release. When Release 1.5 D-3, with Lawful Intercept is released (Future), many of4the IS-53 Call Delivery features will have to be disabled.5Short Message Services are supported as listed in Table 1-6.6Table 1-6 Short Message Services7Service Option DescriptionShort message delivery–point-to-point (SMD-PP)SMD-PP provides delivery of a short message. The SMD-PPservice attempts to deliver a message to a Globalstar UTwhenever the UT is registered even when the UT is engaged ina voice or data call.8
Description of the Globalstar System GS-TR-94-0001Revision E1-5The IS-41 SMS will be compliant with IS-637. A few examples will clarify how MT SMS is1envisioned (future) to operate:21. If a short message comes into the gateway from the SMSC that is less than about 653characters (45 characters of payload) it will be routed to the UT over the paging channel.42. If an SMS message arrives while the traffic channel is set up, it will be routed over the already5established traffic channel. This can be a message of up to about 246 characters (2006characters of payload).73. If a long message arrives and a traffic channel is not set up, it will be set up and the SMS8message will be sent.9The Gateway will support about 5,000 Busy Hour Short Message Access (BHSMA).10Lawful Intercept: The SMS LI will be supported as Call Associated Data (CAD) in future software11release 1.5 D3.12There are several other items that may be considered services listed in Table 1-7. These are primarily13associated with validating the caller and with providing privacy.14Table 1-7 Miscellaneous Services15Service Option DescriptionAuthentication Authentication provides a secure way to identify authorizedsubscribers in order to prevent fraudulent use of the networkresources.Voice Privacy (VP)(Function provided in different manner)VP provides a degree of privacy for the subscriber over theGlobalstar Air Interface. When VP is invoked, the speech ortraffic channel used is encrypted.Data Privacy(Function provided in different manner)Over the Air Encryption is supported. Private keys betweenSM and Authentication Center.Signaling Privacy(Function provided in different manner)Over the Air Encryption is supported. Private keys betweenSM and Authentication Center.Security Module (SM) in the context above should not be confused with the GSM Subscriber16Identification Module (SIM). It is a security module function. The over the air encryption of traffic is an17algorithm similar to the GSM A5 algorithm.18The traffic channel is encrypted. Signaling to set up the call is not encrypted.19
Description of the Globalstar System GS-TR-94-0001Revision E1-6Table 1-8 lists services that may be offered in the future. They are not presently within the scope of1work. The initial offering will include 3-way calling. If Conference Calling (CC) is adopted later, the2older service could be dropped or continued.3Table 1-8 Future IS-41 C Services4Future IS-41 C ServicesAcronym Service DescriptionCPT Cellular Paging TeleserviceCMT Cellular Messaging TeleserviceSPINA Subscriber PIN Access A PIN is required. Network based lockout feature.CC Conference Calling Provides ability to connect more than 3 parties.FA Flexible Alerting A call to a pilot number to alert several numberssimultaneously.MWN Message Waiting Notification Informs subscribers a voice message is waiting.MAH Mobile Access Hunting Causes a call to a pilot directory to search a list of enrolledsubscribers. Terminates with the first available subscriber inthe list.PCA Password Call Acceptance This is a call-screening feature that limits incoming calls tosubscribers able to provide a password.PL Preferred Language Allows the subscriber to specify language for networkservices. This includes help lines, announcements, messagewaiting notifications and SMS.VMR Voice Message Retrieval Allows subscriber to retrieve voice messages.VP Voice Privacy Provides a degree of voice privacy.SP Signaling Privacy Provides a degree of signaling privacy.PACA Priority Access and ChannelAssignmentAllows subscriber to move to top of queued list. Availablein levels, permanent or on demand. Called numbers such as911 may be given priority at the Service Provider option.RFC Remote Feature Control Calls to a special RFC directory number validated by a PINcan be used to activate features. DTMF digits are required.SCA Selective Call Acceptance Allows only calls whose Calling Party Numbers are in ascreening list.SPINI Subscriber PIN Intercept A PIN is required. User Terminal based lockout.These are mentioned here so that we recognize that these may be offered eventuality and Globalstar will5do nothing in the design to preclude their incorporation at a later date.6Globalstar has some of the functions with some interpretation specifically:7
Description of the Globalstar System GS-TR-94-0001Revision E1-71. MWN: Message Waiting Notification is mechanized via the SMS.12. VMR: Facilities are available to access voice messages although not precisely as specified in2IS-41.33. VP: The Traffic Channel is encrypted.44. SP: Any signaling within the traffic channel is encrypted.55. PACA: The User Terminal, the GAI, and the Gateway support 10 priority levels. These may6be used to control which call gets resources. Calls that are setup are not broken down to7support PACA functions within Globalstar.8
Description of the Globalstar System GS-TR-94-0001Revision E1-81.3 GSM Services1The Globalstar Gateway can incorporate a GSM switch or the Gateway can be utilized with an external2GSM switch. In either case the Gateway proper is connected to the GSM switch by the GSM A13interface. This section lists the bearer services and teleservices supported by the Alcatel GSM MSC4Table 1-9 Bearer Service - Full Duplex Asynchronous Data5Bearer Service - Full Duplex Asynchronous DataAcronym Service DescriptionBS 21 300 bps Asynchronous Full Duplex Data Circuit - AsynchronousBS 22 1200 bps Asynchronous Full Duplex Data Circuit - AsynchronousBS 23 1200/75 bps Asynchronous Not SupportedBS 24 2400 bps Asynchronous Full Duplex Data Circuit - AsynchronousBS 25 4800 bps Asynchronous Full Duplex Data Circuit - AsynchronousBS 26 9600 bps Asynchronous Full Duplex Data Circuit - AsynchronousThe Information Transfer may be 3.1 kHz (External to Public Land Mobil Network (PLMN)). The Gateway will notsupport an Unrestriced Digital Interface (UDI). The connection is digital within the PLMN. The service can betransparent (T) or Non Transparent (NT). Transparent service is characterized by constant throughput, constant transitdelay and variable error rate. Non-Transparent service is characterized by improved error rate with variable transit delayand throughput.6The Globalstar Air Interface is a packet system. The top rate for a single channel is 9.6 kb/s. This7includes some overhead. This means Globalstar will not support a true 9.6 kb/s throughput service.8The best estimate is the actual throughput will be on the order of 7.2 kb/s. The difference is required for9overhead. The data connections on each end can operate asynchronously at 9.6 kb/s so that can be the10“apparent peak” service rate. Expansion buffers will be required to allow the peak rate of 9.6 kb/s with11an average around 7.2 kb/s.12Services Requiring Constant Transit Delay: The Globalstar Air Interface is a packet data system13that exhibits a high error rate. While some of the errors can be corrected by Forward Error Correcting14Codes, repeat transmissions will be required. This means:151. Through put time delay is variable.162. Cannot support true synchronous operation17There are ways, with flow control, to provide these as “apparent” services by providing smart18equipment at the ends of each link.19
Description of the Globalstar System GS-TR-94-0001Revision E1-9DTAP Based Services: Any services that use the DTAP messages can be supported as long as the1switch and the User Terminal support the service. DTAP messages are passed transparently thorough2the gateway, the air interface, and the Globalstar User Terminal.3GSM Data Services: GSM Asynchronous Services are targeted for Release 1.5 D4 (future). This is4required for before Synchronous Services could be considered even with elastic buffer equipment in the5link termination equipment.6Table 1-10 Bearer Service - Full Duplex Synchronous Data7Bearer Service - Full Duplex Synchronous Data Service TypoAcronym Service DescriptionBS 31 1200 bps Synchronous Data Circuit, Duplex SynchronousBS 32 2400 bps Synchronous Data Circuit, Duplex SynchronousBS 33 4800 bps Synchronous Data Circuit, Duplex SynchronousBS 34 9600 bps Synchronous Data Circuit, Duplex Synchronous (not supported)The Information Transfer may be Unrestricted Digital (UDI) or 3.1 kHz (External to PLMN). The connection is digitalwithin the PLMN. Operating mode can be transparent (T) or Non Transparent (NT). Transparent service ischaracterized by constant throughput, constant transit delay and variable error rate. Non-Transparent service ischaracterized by improved error rate with variable transit delay and throughput. Synchronous operation can besimulated in Globalstar by external equipment. Throughput is at a lower rate.Technically this service could be offered. The Service Provider must provide some end to end8adaptation equipment on each end to make the link look synchronous. Throughput is limited by the flow9control. Specifically, end to end encryption devices can be used that normally operate with10synchronous links.11Table 1-11 Bearer Service - PAD Asynchronous Data12Bearer Service - PAD Asynchronous Data Service TypeAcronym Service DescriptionBS 41 300 bps Asynchronous Data Circuit, Duplex AsynchronousBS 42 1200 bps Asynchronous Data Circuit, Duplex AsynchronousBS 43 1200/75 bps Asynchronous Data Circuit, Duplex AsynchronousBS 44 2400 bps Asynchronous Data Circuit, Duplex AsynchronousBS 45 4800 bps Asynchronous Data Circuit, Duplex AsynchronousBS 46 9600 bps Asynchronous Data Circuit, Duplex AsynchronousPAD: provides an asynchronous connection to a Packet Assembler/Disassembler. This service is available only formobile originated calls.
Description of the Globalstar System GS-TR-94-0001Revision E1-10Table 1-12 Bearer Service - Packet Synchronous1Bearer Service - Packet SynchronousAcronym Service DescriptionBS 51 2400 bps Synchronous Data Circuit, Duplex SynchronousBS 52 4800 bps Synchronous Data Circuit, Duplex SynchronousBS 52 9600 bps Synchronous Data Circuit, Duplex SynchronousProvides a synchronous connection to a packet network. Can be simulated in Globalstar by external equipment.Throughput is at a lower rate.2Globalstar is a packet system. It does not directly support synchronous services. Devices on each end3can operate so that the connection is “apparent” synchronous. True synchronous operation is not4feasible. Technically this service could be offered. The Service Provider must provide some end to end5adaptation equipment on each end to make the link look synchronous. Throughput is limited by the flow6control. Specifically, end to end encryption devices can be used that normally operate with7synchronous links.8Table 1-13 Teleservices Speech9Teleservices - SpeechAcronym Service DescriptionTS 11 Telephone Service This is the basic voice telephone service.TS 12 Emergency Calls Emergency Calls do not require registration. They can be onIMSI or IMEI.The Gateway requires an IMSI for all calls. This means emergency calls too. The User Terminal could10be designed to provide a pseudo-IMSI so that at UT could be used without the SIM.11Table 1-14 Teleservices - Short Message Service12Teleservices - Short Message ServiceAcronym Service DescriptionMT/PPTS 21Short Message Mobile TerminatedPoint-to-PointPermits the SMS service center to send a message to anysubscriber that is less than 160 ASCII characters (future)MO/PPTS 22Short Message Mobile OriginatedPoint-to-PointPermits any subscriber to send a message to any othersubscriber that is less than 160 ASCII characters. The SMSservice center acts as a store and forward node (future).13
Description of the Globalstar System GS-TR-94-0001Revision E1-11An IS-41 Mobile Originated only variant will be offered in the near future. The Alcatel switch will1require modification to support Mobile Originated SMS. Although the switch supports SMS Mobile2Terminated broadcast, Globalstar does not support this service.3
Description of the Globalstar System GS-TR-94-0001Revision E1-121Table 1-15 Teleservices - Facsimile Transmission2Teleservices - Facsimile Transmission (Not Supported by Globalstar)Acronym Service DescriptionTS 61 Alternate Speech and Facsimile Group3 (T or NT)Speech and data can be alternated during the call.TS 62 Automatic Facsimile Group 3 (T or NT) Dedicated service.Operating mode can be transparent (T) or Non Transparent (NT). Transparent service is characterized by constantthroughput, constant transit delay and variable error rate. Non-Transparent service is characterized by improved errorrate with variable transit delay and throughput.Although the Alcatel switch supports these modes, they are not available over Globalstar. The air3interface operates NT. Timing could be adjusted so digital FAX machines will not timeout.4Table 1-16 Supplementary Services - Line Identification5Supplementary Services - Line Identification - GSM 02.81 (Not Supported by Globalstar)Acronym Service DescriptionCLIP Calling Line IdentificationPresentationPermits the called party to receive the line identity of thecalling party.CLIR Calling Line IdentificationRestrictionPermits the calling party to block his line identity to the calledparty.COLP Connected Line IdentificationPresentationThe calling party can receive the line identity of theconnected party.COLR Connected Line IdentificationRestrictionPermits the connected party to block his line identity to thecalling party.COLP and COLR are mandatory.6
Description of the Globalstar System GS-TR-94-0001Revision E1-13Table 1-17 Supplementary Services - Call Forwarding1Supplementary Services - Call Forwarding (CF) GSM 02.82Acronym Service DescriptionCFU Call Forwarding Unconditional Incoming calls are forwarded to another number.CFB Call Forwarding - Busy Line is busy, calls are sent to another number.CFNRy Call Forwarding on No Reply When there is no reply within a specified period of time,calls are sent to another number.CFNRc Call Forwarding on Mobile SubscriberNot ReachableWhen the called party is not reachable, calls are forwardedto another number.Table 1-18 Supplementary Services - Call Waiting & Call Hold2Supplementary Services - Call Waiting (CW) and Call Holding (HOLD) GSM 02.83 (Not Supported by G*)Acronym Service DescriptionCW Call Waiting Notify the called party that a call is waiting.HOLD Call Hold Place an active call on hold.Table 1-19 Supplementary Services - Closed User Group3Supplementary Services - Closed User Group GSM 02.85 (Not Supported by Globalstar)Acronym Service DescriptionCUG Closed User Group Communications permitted only with group. The switchsupports a MS belonging to up to 10 CUGs.4Table 1-20 Supplementary Services - Advice of Charge5Supplementary Services - Advice of Charge GSM 02.86 (Not Supported by Globalstar)Acronym Service DescriptionAOC Advice of Charge Information Provides and estimate of the size of the bill.AOC Advice of Charge Charging Provides an accurate charge to support immediate billing(e.g. Taxi phone).The Alcatel GSM-MSC supports “Warm” billing. Partial records can also be obtained for long calls.6The SP should consider carefully before offering any service that requires “Hot Billing”.7
Description of the Globalstar System GS-TR-94-0001Revision E1-14Table 1-21 Supplementary Services - Call Barring1Supplementary Services - Call Barring (CB) GSM 02.88Acronym Service DescriptionBAOC Barring of All Outgoing Calls There are no outgoing calls except emergency calls.BOIC Barring of Outgoing InternationalCallsBars international calls from the PLMN in which thesubscriber is presently located.BOIC-exHC Barring of Outgoing InternationalCalls except those directed to theHome PLMN CountryOutgoing calls are barred except local calls and to the homePLMN country.BAIC Barring of All Incoming Calls No incoming calls are permitted. GSM 02.88BIC ROAM Bar Incoming Calls - Roaming No incoming calls are permitted when roaming outside thehome PLMN.2Table 1-22 Supplementary Services - Multiparty Services3Supplementary Services - Multiparty Services (Not Supported by Globalstar)Acronym Service DescriptionMPTY Multi Party Service Establish and delete multiple parties in any order.Conference Calling or Multi-Party Service is mandatory.4
Description of the Globalstar System GS-TR-94-0001Revision E1-151.4 Globalstar Specific Services and Quality1The following services and statements result from the Globalstar implementation and apply to both GSM2and IS-41.34Globalstar Specific ServicesPosition Location (high resolution), 300 m (Future)Position Location (low resolution), 10 kmGlobal RoamingTerminal ServicesCDG Sleep Mode5Internet Services: Internet services have been tested and operate reliably. In order to offer the6service, the gateway must supply some modem equipment and must interface at the Selector Bank7Subsystem (SBS). Offering the packet service implies Internet, e-mail, stock quotes and a host of8attractive services. . The billing is quantized to 0.1 second intervals. Byte based billing is not9supported. The Gateway support will be in Release 1.5 D2, which should be in the near future10Slotted Mode: An IS-41 slotted mode operation will be available is software release 1.5 D211scheduled for the near future. This will increase battery receive battery life on the order of 2:1. Longer12slot delays cause unacceptable latency and result in very slight improvements. This IS-41 service is13mechanized by storing the slots in the VLR located in the gateway. It would be necessary to access the14GSM VLR to offer slotted mode as a GSM feature. Slotted mode is turned off when the handset is15placed in a car kit.16Throughput Rates: The data rate of the air interface plus overhead for the radio link protocol, etc.17limits the effective data rate to approximately 7.2 Kb/s (if enough power has been allocated and there is18no blockage of view). It is possible to interface to a higher rate service at the network interface (e.g.,19V.32), but the actual data rate is limited.20Short Message Service: The gateway will support interfaces to GSM and IS-41 short message21service centers for SMS.22Voice Quality - Voice service is based on a Code Excited Linear Prediction (CELP) variable rate23vocoder. The voice processing will incorporate a procedure to aid in cancellation of background noise.24The voice quality will meet or exceed the voice quality provided by IS-96A, the terrestrial CDMA25standard. This superior voice quality can be offered at the lower data rates in large part due to the26adaptable rate vocoders used in Globalstar. The voice quality cited is based on a Ricean channel model27
Description of the Globalstar System GS-TR-94-0001Revision E1-16that requires a forward link Eb/No and return link Eb/No as defined in the link budget. A soft1degradation is incorporated into the design. In marginal areas where the User Terminal cannot generate2sufficient power to close the link, the peak data rate is reduced to 4.8 Kb/s or 2.4 Kb/s. This will3provide intelligible voice communications in areas that otherwise could not be served. The Vocoders4will incorporate echo cancellation, which can be disabled if this function is provided by the network.5Data Quality - Data services are provided up to 7.2 Kb/s. The a Bit Error Rate contributed by6Globalstar is less than 1 X 10 -6. Higher terminal rates (e.g. 9.6 Kb/s) can be processed if the7equipment incorporates elastic buffers to accommodate the required flow control.8Encryption: Over the air signaling (in band), voice and data encryption is offered.9Registration - The Gateway is capable of providing a position location function on the User Terminal10with which it is communicating. The accuracy is within 10 km for registration. This is used to determine11assignment of User Terminals to Gateways.12Location Service: Globalstar can locate the position of a User Terminal and provide the location as a13service in the future. Accuracy of the position location service is a function of several variables14including:15a. Number of Satellites in View.16b. Position Accuracy of the Satellites17c. Geometry of the User Terminals, Satellites and Gateways.18d. The length of time that the User Terminal is connected to the Gateway.19The architecture will support better precision once the gateway locations are known with sufficient20accuracy and the topographical maps are correctly registered. With this a likely service, this document21includes some description of the position location methods.22Location Privacy - The location of a user is protected. Only duly constituted authorities will have23access to these data unless approved by the owner of the User Terminal.24Tracking Service - The Gateway is able to use sequential position locations to determine and maintain25tracking services for mobile users. Offering these services is dependent upon the legality within the26regions supported by the Service Providers.27
Description of the Globalstar System GS-TR-94-0001Revision E1-171.5 External Network Supported Services1The Gateway design will incorporate nothing to block network operator value added service such as2those listed in Table 1-23. Whether the service can be offered depends upon the details of how the3service offering is to be interfaced with the Gateway. This assumes of course that the Globalstar Air4Interface (GAI) and the User Terminal (UT) will support the value-added service.5Table 1-23 External Network - Value Added Services6External Network - Value Added ServicesAcronym Service DescriptionAutomatic IMSI replacement Old SIM remains valid until first use of new SIM.Operator Determined BarringCAMEL Phase I GSM Mobile Intelligent networkCore-INAPWarm/Hot Billing Billing can be to the OMC in less than 5 minutes.Single Numbering One number follows the subscriber.Operator Services Assistance or Help Desk.Operator Defined Barring (ODB) Network operator can bar even if UT selects.Mail Boxes Store and forward Voice, FAX or Digital Messages.Dial in information. Can be Voice, FAX and/or data.Alarm and Wake up calls. Alert under defined conditions.Paging Services Page a SubscriberCredit Control Network Operator Managed.7
Description of the Globalstar System GS-TR-94-0001Revision E1-18This page intentionally left blank.12
Description of the Globalstar System GS-TR-94-0001Revision E2-12. SYSTEM SEGMENT DESCRIPTIONS12.1 Globalstar System2The Globalstar system consists of a Space Segment, a User Segment, a Ground Segment, and a3Terrestrial Network as shown in Figure 2-1.4Satelli teSatelliteSpaceSegme ntSatelli teS-Band Down LinkFixe dMobil eSegme ntUserPortableL-Band Up LinkGatewayC-Band Down LinkC-Band Up LinkGro u ndGlobalstar Data NetworkSegme ntTer r estrialNetworkLongD istan ceCar r ierInternatio na lCarrierPSTN/PLMNPT T PrivateNetworkCellularCar r ierWirel in eTelcoS P C CGSM-MSCTCUGBOGDN InterfaceGO C C SOC CLANCDA5Figure 2-1 Globalstar System Integrates with Terrestrial Network6
Description of the Globalstar System GS-TR-94-0001Revision E2-2The Globalstar system provides communications from any point on the earth surface to any other point1on the earth surface, exclusive of the Polar Regions as shown in Figure 2-2.2345678910111213Figure 2-2 Globalstar Constellation Serves Temperate Areas14The satellite orbits are optimized to provide highest link availability in the area between 70 degrees south15latitude and 70 degrees north latitude. Service is feasible in higher latitudes with decreased link16availability. The Globalstar space segment consists of 48 satellites in 1410 km Low Earth Orbits. The17low orbits permit low power hand sets similar to cellular phones. These satellites are distributed in 818orbital planes with 6 equally spaced satellites per orbital plane. Satellites complete an orbit every 11419minutes. User Terminals in a particular location on the surface of the earth are illuminated by a 16-beam20satellite antenna as it passes over the earth.21User Terminals can be served by a satellite 10 to 15 minutes out of each orbit. A smooth transfer22process between beams within a satellite and between satellites provides unbroken communications for23the users. The orbital planes are inclined at 52 degrees. Coverage is maximized in the temperate areas24with at least two satellites in view, providing path diversity over most of the area. There is some small25sacrifice in multiple satellite coverage at the equator and at latitudes above 60 degrees.26The Gateways to the terrestrial network are illuminated by an earth coverage beam. The Gateway27connects the User Terminal to the terrestrial network via the Gateway. The terrestrial network is not a28part of Globalstar.29
Description of the Globalstar System GS-TR-94-0001Revision E2-32.2 User Terminal1The User Terminals come in several varieties. There are hand held units, mobile units and fixed station2units. The available types of User Terminals are listed in Table 2-13Table 2-1 Production User Terminals4Fixed Terminal Hand Held and MobileGlobalstar Only Dual Mode Globalstar & GSMTri Mode Globalstar & Terrestrial CDMA & AMPS2.2.1 Hand Held and Mobile Units5Typical hand held units are shown in Figure 2-3.6Figure 2-3 Typical Hand Held User Terminal7QualcommTri-modeAMPSCDMAGlobalstarEricssonDual-ModeGSMGlobalstarTelitDual-ModeGlobalstarGSM
Description of the Globalstar System GS-TR-94-0001Revision E2-4Globalstar Mode: Hand held User Terminals look like a standard cellular telephone. These are1multiple mode handsets that operate with the local cellular system or Globalstar. The radiating element2of the antenna is positioned above the head of the user. The antenna is positioned vertically to3effectively utilize the symmetrical radiation pattern of the hand held antenna. The area next to the head is4not used for radiation. This meets the safety requirements.5Cellular Mode: When operating as a cellular mode handset, normal cellular operation can be6expected. Cellular uses a separate and smaller antenna as is the custom with cell phones.7Mobile - The mobile units consist of a hand held unit inserted in an adapter in the vehicle. The Mobile8units typically have a higher gain antenna, a lower noise receiver and a higher RF power output. This is9part of the adapter kit. The improved transmitter and receiver are mounted in the base of the antenna.10The car kit that goes with a mobile typically includes:111. Hands Free Speaker and Microphone122. Outdoor Unit with a superior antenna133. Operation with the Vehicle battery14
Description of the Globalstar System GS-TR-94-0001Revision E2-5Block Diagram - Figure 2-4 is a simplified block diagram of the Globalstar portion of a User Terminal,1which includes Globalstar/CDMA/AMPS.2Figure 2-4 Globalstar User Terminal Block Diagram3Since there is no hand off between the local cellular system and Globalstar, if the user crosses a service4boundary between the local cellular system and Globalstar, the call could be dropped and must be5placed again. The indicators tell the operator that the mode has changed.6The system will not thrash in a boundary area. The user can select the preferred mode. If cellular is7preferred and coverage is not available the UT will drop the call. The call can be placed in Globalstar8mode. This call will continue until the phone is in an idle state. The reverse is also true.9TLV320AVCodec Intel 386EX:2 ch DMA2 ch Serial3 Timer/ctrsWatchdogRefresh ctlChip Sel unitGUM ASIC:rake receiver/deinterlvr/decxmitenc/interleavedig FM , fart123456789*0#LCD DisplayBBII ASICTC554161256K X 16SRAM28F0161Meg X 16FlashTCXO &SynthsRingerAddress16L DataDiagnosticMonitor115.2K Serial I/OChipX810L Add8 bit I&QRef ClkTx IFSync & ClkPowerConverter5.0V PA3.6Vaa3.3VddADSP-2185LVocoder7.2V1.4AHrS BandDownconverterL BandUpconverterRx IFTx AntennaRx AntennaIrqFr_Ref8L Data16.6 MHz Resonator38.4K Serial I/ODataPortRF AssemblySMSocketRS-232translator49.152 MHzClockLNAPA
Description of the Globalstar System GS-TR-94-0001Revision E2-6Function Performed : The start up functions of a User Terminal are programmable. As an example,1when a dual-mode User Terminal first powers up it may attempt to log into the local cellular system.2This addresses a scenario where the cellular system gets first priority to provide the service. If this fails3the User Terminal then attempts to log onto the Globalstar system. Figure 2-5 illustrates a typical4startup scenario within Globalstar.5User Terminal Control on the Traffic Channel State Power-upUser Terminal has fully acquired system timingReceives an acknowledgment to an Access Channel transmission other than an Origination Message or a Page Response Message Note: Not all state transitions are shown. Directed to a Traffic ChannelReceives a Paging Channel message requiring an acknowledgment or response; originates a call or performs registration.Ends use of the Traffic ChannelUser Terminal Initialization State User Terminal Idle State System Access State 6Figure 2-5 User Terminal Startup Scenario within Globalstar7The User Terminal looks for the best satellite pilot signal. When this is found it then switches to the sync8channel and obtains the satellite database and other information. This database facilitates rapid9
Description of the Globalstar System GS-TR-94-0001Revision E2-7acquisition of the pilot for any future calls. To place a call the user dials the number and presses1"SEND". The User Terminal contacts the Gateway via the access channel. The Gateway and the User2Terminal then work together to connect the call and support communications. Since the satellites are3moving, the user is continuously being illuminated by different satellite beams or even different satellites.4Diversity combining within the receivers supports a process of transferring traffic that is completely5transparent to the user. The diversity combining process also provides better call reliability. The hand6off process is accomplished without interruption to the call in process. If the user moves into an area7that shadows or blocks access to one satellite, the space diversity link through a satellite that is not8blocked maintains uninterrupted user communication92.2.2 Fixed Terminals10Fixed station terminals are normally Globalstar only. The fixed User Terminals have a performance11equivalent to the mobile terminal except that the antenna gain and transmitter power may be even higher.12Fixed terminals do not require path diversity to combat fading and blockage. Fixed Terminals must13support seamless beam to beam and satellite to satellite hand of141516171819202122232425Figure 2-6 Typical Fixed Terminal Application26The fixed terminals can operate with a fixed phone, a payphone or other equipment.27 GatewayGatewayPSTN
Description of the Globalstar System GS-TR-94-0001Revision E2-82.3 Gateway1The Gateways are geographically distributed by the service providers to serve their customer base.2Figure 2-7 is a typical Gateway3Figure 2-7 Typical Gateway Installation4Gateways are designed for unmanned operation. A gateway consists of up to four 5.5-meter antennas5as shown on the left and electronics equipment installed in a building or shelter as show on the lower6right. In addition to the equipment racks, the facility supplied by the Service Provider includes prime7power, an Uninterrupted Power System (UPS), as well as any maintenance or office facilities. The8antenna layout is flexible. The major constraint is to place the antennas so that they do not block9visibility of the satellite constellation. Safety considerations for the operating area must also be10observed.11
Description of the Globalstar System GS-TR-94-0001Revision E2-9Figure 2-8 is a simplified block diagram of a typical Gateway.1Figure 2-8 Gateway Simplified Block Diagram2Appearance : The Gateway consists of up to four identical parabolic antennas that are at least 5.53meters in diameter. The antenna structure contains drive mechanisms for positioning the antenna, low4noise receivers and high power transmitters. The antenna structure may be enclosed in a Radome to5provide protection from the environment.6The antennas connect to a building that houses the electronics equipment. The Code Division Multiple7Access (CDMA) equipment, PSTN interface equipment that interfaces with the terrestrial telephone8network, and computer equipment to operate the Gateway and collect status and performance data are9located in the electronics facility.10Function Performed : The Gateway supports voice communications, paging, and data transmissions.11Position location services are also supported.12The Globalstar Gateway connects the Globalstar space segment to terrestrial switching equipment. The13Gateway receives telephone calls from the terrestrial switching equipment and generates Code Division14Multiple Access (CDMA) carriers to transmit through the satellite. The satellite then re-transmits the15signal to User Terminals. These User Terminals may be either hand held, fixed or mobile and located16anywhere within the satellite antenna footprint.17SPCC GW Links E1 or T1BCN MSSLEthernetIFLPSTNSSAPatch PanelCSUNISGWRDBVLRPatch PanelPatch PanelBSCI GSMMSCVLRT1/E1TrunksSBSCIS(DISCO)GTSRLTFUGPS RcvrRouterSPCC RouterGDNFL7 561211108 4219 3Up ConverterSSPARLLNADownConverterAntennas(up to 4)TCU PanelTCUTCUTCUTCUGSS(Gateway Switching System)GCS(Gateway CDMA System)GMS(Gateway Management System)GOCCSOCCTCU(Telemetry & Command Unit)ROPIGRS(Gateway RF System)DigitalCabinets(up to 13)DemodCardsFL CabinetRHCPLHCPRHCPLHCPGSMHLRIS-41HLRE1TrunksSS7SS7SS7VMEBackplaneCommonCardReceiveCabinets(up to 13)ReceiverCardsControllerCardSBS Shelf1/96 callsSelectorCards (12)InterfaceCardΣΣGCUT1FL Shelf(40)5/polarize/antUpconverterCardsModulatorCardsGDN Router147*2580369#DGlobalstarDIGITAL BYABCTFUCabinet(2)SplittersTFUCabinet(2)Splitters147*2580369#ON OFFDGlobalstarDIGITAL BYVME CageCCPVME CageGWCVME CageSS7ServerCDAVIP213Trunk Set Combinations(most likely):· IS-41 territory:· GSM territory:T11 22 3OMCGMOPI
Description of the Globalstar System GS-TR-94-0001Revision E2-10In the return direction, the User Terminal transmits to the satellite(s) and the satellite(s) re-transmit the1signal to the Gateway. The Gateway connects the call to terrestrial switching equipment, which can then2connect to any subscriber using the standard telephone system. Connections can also be made to3terrestrial cellular subscribers or to other Globalstar User Terminals.4The Gateways are designed to operate without operator intervention. Maintenance is performed by5service provider personnel as required. Status may be remotely monitored by the Service Provider's6Control Center (SPCC).7Functions of the major elements of the Gateway are listed below.8Telemetry and Control Unit (TCU): The TCU acts as a telemetry and control interface between the9satellite constellation and the SOCC. The TCU interfaces with the SOCC via the router in the GMS.10The TCU interfaces with individual satellites via the GTS and the GRS.11Gateway RF Subsystem (GRS): The GRS interfaces the gateway to Globalstar users via the12Globalstar satellite constellation.13Gateway Management Subsystem (GMS): The GMS interfaces the gateway with external14management entities (SPCC). The GMS performs non-real-time configuration and management of the15gateway.16Call Detail Access (CDA): The Call Detail Access (CDA) is a separate, fault-tolerant workstation17within the GMS, with stricter reliability requirements than the rest of the GMS. The CDA uses a18confirmed-transfer protocol to retrieve accounting from the SBS, CCP and GC.19CDMA Subsystem (CS): The CS performs real-time operation of individual calls, maintaining the20integrity of each physical link and performing physical layer format conversion between the CDMA21wave form on the GRS side and PSTN signals on the GSS side.22Gateway Controller (GC): The GC is responsible for operation and supervision of the CS and of the23GRS.24Gateway Transceiver Subsystem (GTS): The GTS is responsible for the physical layer25implementation of the Globalstar Air Interface. Under the control of the GC, control elements in the26GTS set up and operate overhead and traffic channels as required.27CDMA Interconnect Subsystem (CIS): The CIS provides packet-level and timing reference28connectivity between all subsystems in the gateway.29Selector Bank Subsystem (SBS): The SBS provides an interface between the SSA and the CS, and30performs layer two operation and radio link management of individual traffic channel circuits. The SBS31also performs service option-specific processing of traffic channel data. Service options may include32voice, data, and short message services.33
Description of the Globalstar System GS-TR-94-0001Revision E2-11Base Station Controller Interface (BSCI): the BSCI provides an interface between the CDMA1Subsystem (CS) and the GSM MSCs. The BSCI implements the BSC side of the A1 Interface,2providing the SS7 transport, the protocol discrimination function, BSSMAP processing, and passes the3DTAP messaging between the GSM MSC and the CS. The BSCI can be configured to terminate4multiple A1 Interface links between multiple GSM MSCs. The configuration and setup of the BSCI is5controlled through the GMS interface (by way of the CS).6Time and Frequency Unit (TFU): The TFU provides a highly reliable and stable source of timing and7frequency references to the CS and to the GRS. The TFU output is synchronized to the Global8Positioning System (GPS).9Gateway Switching Subsystem (GSS): The GSS interfaces the gateway to the PSTN and controls10the state of each call.11Separation of CDMA & Switch: Although not often done, it is technically feasible to separate the12Selector Bank Subsystem from the switch equipment. The interface between the two elements is an13unformatted T1. Communications Service Units (CSUs) could be used at this point to separate the14switching subsystem from the remainder of the gateway.15
Description of the Globalstar System GS-TR-94-0001Revision E2-122.4 User Terminal and Gateway Interaction1Hand Off: The moving satellite constellation requires hand off to different satellites and to different2beams. In general, hand off is transparent to the user. Hand off on the forward link does not imply3hand off on the return link.4Forward Link: In the forward link direction (from the Gateway to the User Terminal), hand off is5totally under control of the Gateway. The User Terminal finds pilots and reports quality to the Gateway.6When a second pilot is seen, the quality is reported to the Gateway. If the Gateway determines that it is7advisable, the Gateway will instruct the User Terminal to incorporate the signal into the diversity8combiner. At all times the user terminal is using a fast algorithm to search for other pilots. Once a9suspected pilot is detected, it is turned over to one of the fingers used as a clincher. So at one point in10time, the User Terminal may have 3 fingers active. One is the traffic finger, one is used for diversity11combing and the third finger is used as the clincher. In the forward direction the role of the User12Terminal can be summed up as the proposer. The Gateway can be viewed as the disposer. The User13Terminal suggests which pilots should be used. The Gateway decides.14Return Link: In the Return Link direction, the Gateway uses up to 6 fingers. Eb/No is measured. If15the Eb/No is above a usable threshold it is added into the diversity combiner multiplex. New signals are16added in until the Gateway runs out of fingers. A stronger signal will not cause the Gateway to take a17weaker signal out of the diversity combining process as long as it is above the threshold. Once a signal18drops below the acceptable threshold, it will be taken out of the diversity combining process and the19finger released for assignment to other incoming User Terminal signals.20Soft Hand Off: In soft hand-off, two or more received signals through different links are simultaneously21demodulated, combined, and decoded by the same entity. It is characterized by commencing22communications using a new pilot on the same CDMA frequency before terminating communications23with the old pilot. This is a hand off occurring while the user terminal is operating on the Traffic24Channel.25Hard Hand Off: In hard hand off, the receiving entity stops demodulating and decoding information26transmitted on one link and starts demodulating and decoding information transmitted on another link27with possible loss of information. A hard hand off is characterized by a temporary disconnection of the28Traffic Channel. Hard hand off occur when the user terminal changes frequency or frame offsets. The29“temporary disconnect” does not mean the call is dropped. There is sufficient hysteresis in the system30to avoid dropping the call.31Access Channel: The access channel is slotted aloha (TDMA). It does not use diversity. This channel32is activated by the User Terminal to contract the gateway in the event the User Terminal is attempting to33initiate a call.34
Description of the Globalstar System GS-TR-94-0001Revision E2-132.5 Globalstar Control Centers1There are two operations control centers. Each is completely capable of operating the network and2managing the satellite constellation. There are two to circumvent the possibility of earthquake, power3grid failure or other disaster. One is located in San Jose, California and one is located near4Sacramento. Each includes:51. Ground Operations Control Center.62. Satellite Operations Control Center73. Globalstar Business Office8The integrated control center is shown below in Figure 2-9910111213141516171819202122Figure 2-9 Globalstar Control Center23
Description of the Globalstar System GS-TR-94-0001Revision E2-142.5.1 Ground Operations Control Center1Ground Operations Control Centers (GOCC) are responsible for planning and management of the2communications resources of the Globalstar satellite constellation. This is coordinated with the Satellite3Operations Control Center (SOCC). Figure 2-10 illustrates how the Ground Segment Equipment4operates together to support Globalstar Communications Functions.5• Relays communications• Relays signalling from gw to users• Relays signalling from user to gw – Access request – Power change request – RegistrationC-BAND – pilot– paging – ephemeris update – synch– power control• signalling• voice & data communications• multi-mode - including cellularL-BAND(return)S-BAND(forward)Globalstar Data Network (GDN)Ground OperationsControl Center(GOCC)(SOCC)• connect user to switch• data for billing – signalling – voice & data comm• manage within resourcesGateway(GW)• Provides orbits • Satellite health • Battery state • Selects filters • Sets gains Real Time• allocate resources – satellite – gateway• monitor performance • generate traffic plans PlanningFile: CommFuncSatellite OperationsControl Center- Downloads6Figure 2-10 Ground Segment Support for Communications7The GOCC and the SOCC may be collocated or they may be physically separated with linkage via the8Globalstar Data Network as shown in Figure 2-10. If the two are collocated, the connection will be by9a Local Area Network (LAN). In either case, the GDN connections are required to accommodate10failure scenarios. These collocations will reduce long term personnel costs since both the GOCC and11the SOCC are manned facilities.12Figure 2-11 is a simplified block diagram of the Ground Operations Control Center (GOCC)13
Description of the Globalstar System GS-TR-94-0001Revision E2-15Local Area Network(redundant)4 mmTapeSubsystemManagementApplicationsSystemsAdmin.ConsoleFileServerLarge ScreenDisplayProcessorWorkStationsOperationsRemoteDisplayLocalSOCCGDNHighPerformanceComputerResourceAllocationWorkStationsRemoteDisplayBackups andArchivesPrinters &ScannersVisitorDisplayDisksGPSRcvr1Figure 2-11 GOCC Simplified Block Diagram2In addition to the planning functions, the GOCC is responsible for monitoring performance and ensuring3that the Gateways remain within the allocated satellite resources.4Appearance: The Ground Operations Control Center consists of a number of workstations in a5control center environment. Besides the workstations used by the operators, there are other displays in6the control center.71. There are large screen remote displays located in the area. The computer operators can8project any of the screen displays onto the large screen displays and continue operations. The9large screen displays will update as the status changes.102. There is also a large display that shows the position, coverage and status of the space11segment.123. A separate animated communications network display indicates the number of circuits flowing13through Globalstar and indicates any congestion or circuit outages.14Function Performed: The Ground Operations Control Center (GOCC) is the planning element for the15Globalstar communications system. The redundant GOCCs plan the communications schedules for the16Gateways and control the allocation of satellite resources to each Gateway. The Gateways process real17time traffic within these assigned resources. The GOCC incorporates facilities to:18
Description of the Globalstar System GS-TR-94-0001Revision E2-161. Generate long-range plans based on projected traffic requirements and constraints such as1available frequencies, Gateway capacities, service areas, etc.22. Monitor usage and refine plans based on measured performance of the system and3constraints imposed by the SOCC.43. Report satellite usage to the Satellite Operations Control Center.5The GOCC facilities are operated 24 hours per day.6Emergency Power: Critical elements of the ground equipment require a no-break power source or7some form of backup power.89
Description of the Globalstar System GS-TR-94-0001Revision E2-172.5.2 Satellite Operations Control Center1The Satellite Operations Control Center (SOCC) manages the satellites. Redundant SOCCs control2the orbits and provide Telemetry and Command (T&C) services for the satellite constellation. In order3to accomplish this function on a worldwide basis, the SOCC communicates with T&C units collocated4at selected Gateways. The T&C units share the RF links with the Gateway communications equipment5to relay commands and to receive telemetry. Figure 2-12 illustrates how the various elements of the6Globalstar Ground Segment operate together to support the command and telemetry functions.7• T ransmit satellite telemetry• R eceives & acts on commands – D ecrypts – S tores if time taggedC-BANDGlobalstar Data Network (GDN)• A llocates satellite Tracking schedules resources to GWs• P rovides gateway (GOCC)• M onitors telemetry• E ncrypts commands• O rbit determination• I nforms GOCCs – S atellite available – S atellite capacity – S atellite ephemeris(SOCC)• S ends commands• R eceives telemetry• T racks satellites – P rogram trackGateway(GW)TCUFile: ContFuncGround OperationsControl CenterSatellite OperationsControl Center8Figure 2-12 Ground Equipment Support for T&C Functions9Telemetry Down link and Command Up link: Globalstar satellites continuously transmit telemetry10data, which contains orbit position data and measurements of current on-board health and status of the11spacecraft. Because both the telemetry stream and the communications payload feeder links will utilize12C-band communications, T&C operations utilize antennas and RF-equipment at selected13communications Gateways. Since only selected Gateways have T&C units, telemetry is available only14when an antenna with a T&C Unit is tracking the satellite. All Gateways equipped with T&C Units15have the ability to command the satellite. The T&C unit consists of special purpose RF cards and a16DSP controlled by a Pentium based Personal Computer. A single self-contained rack will17accommodate up to 5 T&C Units (1 spare). The T&C units are designed to run automatically, with18
Description of the Globalstar System GS-TR-94-0001Revision E2-18control from the SOCC. Routine staffing is not required. Any maintenance will be provided by service1provider personnel dispatched on call from the Globalstar Control Center (GCC).2Telemetry Reception: Telemetry from each satellite will be received at the T&C Gateway that have3an antenna trained on that satellite. The T&C unit will be able to either directly send the demodulated4data (bent-pipe mode) or store it for later transmission (store and forward mode). Stored data will be5sent to the SOCC upon SOCC request, typically during a period of lower system utilization or lower6communications network costs. The SOCC will coordinate the T&C data transmission to avoid7receiving identical data sets from multiple T&C sites. The telemetry data sent from the T&C site is8routed to the SOCC as packet messages on the Globalstar Data Network (GDN). Should more than9one SOCC be providing support, the T&C equipment will route the data to multiple destinations.10Command Transmission: Commands received from the SOCC are immediately transmitted to the11satellite (bent pipe mode only). Depending upon the command, the satellite can execute the command12immediately or store the command for execution at a later time. The TCU does not incorporate a13command storage facility. The SOCC is responsible for directing the command message to the proper14T&C at the correct time for transmission.15SOCC Operations: The SOCC will receive minor frames over the Globalstar Data Network. Data16received in the telemetry bent-pipe mode is immediately routed to the user workstations assigned to17monitor or control the specific satellite. At any one time, all satellites in contact are automatically18monitored by the software, with only selected satellites directly monitored by a member of the flight19operations team. A single workstation can monitor up to 6 satellites. An operations controller may20have asked for up to 6 specific satellites to monitor or may have defined the criteria by which the system21can automatically determine which satellites are to be monitored. For example, the controller could22request to see all satellites for which real-time data is being received for which the power subsystem23monitoring software detects a possible area of concern.24Because of the very low telemetry rates, it is possible to have remotely located workstations, connected25to the SOCC via simple modem or ISDN communications. A workstation at the satellite26manufacturer's facility, for example, could routinely be used to monitor a single satellite to support27problem investigation, routine monitoring, or analysis.28The SOCC is also responsible for coordinating activities with the GOCC. The three primary interface29functions are:30a. Orbit position information: The SOCC will provide information to the GOCC so that each31Gateway can accurately track each satellite. The data will consist of data tables sufficient to allow the32Gateway software to generate its own contact lists.33b. Utilization statistics: The GOCC will provide statistics to the SOCC pertaining to the actual34communications quality and utilization (Gateway assessment) of each satellite. This information will be35correlated with satellite telemetry to distinguish between expected and anomalous behavior.36
Description of the Globalstar System GS-TR-94-0001Revision E2-19c. Spacecraft status: The SOCC will report to the GOCC spacecraft/transponder availability. This1data will include limitations associated with any satellite, which may constrain or preclude its use for2communications.3Use of Multiple SOCCs : Two SOCCs are planned. The San Jose, California location will support4primary operations and a second one in El Dorado Hills, California serves as a backup to the prime.5Both SOCCs will be able to receive telemetry data from the same satellites so that dual-site monitoring6and "hot backup" functions could be supported; however, the baseline is a single string SOCC7operation.8The main reason for the second SOCC is to create a backup operational facility in case of a9catastrophic failure (fire, etc.) at the primary site. The two SOCCs, however, could be used routinely10to share the load between two sites, to conduct training and to support development and test of11software upgrades.122.5.3 Globalstar Business Office13To support the Globalstar Business Office (GBO), the Globalstar Accounting & Billing System (GABS)14is collocated with the GOCC and the SOCC. The GABS is responsible for all financial activities15associated with Globalstar.16Appearance: The GABS is a client/server system with many workstations and the requisite office17facilities required to support the assigned accounting and billing activities. The server for the primary18GABS is located in the GCC. A back-up GABS server is located in the alternate GCC. Multi-19platform client support is provided.20Functions: The GABS provides basic accounting and billing functions for GLP. The accounting21functions are provided by a Commercial - Off - The - Shelf (COTS) package, ORACLE Financial, and22include accounts payable, accounts receivable, general ledger, purchasing , and financial planning23software. The wholesale billing function, provided by custom developed software, receives data from24both the Gateways and the Service Providers. These data, call usage summaries, subscriber counts,25etc. are used to calculate charges for usage of the Globalstar system and to generate bills which are sent26to the service providers monthly.27
Description of the Globalstar System GS-TR-94-0001Revision E2-202.6 Globalstar Satellite1The Globalstar satellite is a simple low cost satellite designed to minimize both satellite costs and launch2costs. A pictorial of the satellite and some of the major characteristics are shown in Figure 2-13.3RELIABILITY• Ps = 0.85 for 7.5 years, providing 15 of 16 beam pairsAUTONOMY• FDIR• Safe Mode (Earth & Sun)TELEMETRY & COMMANDING• C-Band CMD/TLM - 1.0 KBPS• Real Time, Stored and Macro• CMD Encryption - KI - 23• <500 Hardware Commands • <500 Hardware Telemetry ItemsORBIT DETERMINATION• GPS Tensor (<90 M. Semi-Major Axis)ATTITUDE DETERMINATION ( 0.7 half cone)• Earth Sensor• Magnetometer• 3 Sun Sensors ATTITUDE CONTROL (NORMAL)• Yaw steering & Momentum Bias• 4 Reaction Wheels• Mag. Torquer along X&YSTRUCTURE• Rigid Al Frame• Al Honeycomb PanelsMASS• <450 kg (Wet)ELECTRICAL POWER • 1.1 kW EOL Solar Array• Single-Axis Track(Rotate)• Peak Power Tracker• 14-23 V Unregulated Bus• Ni- H2 Battery, 14 Cells, 64 AhTHERMAL• Generally Passive• Heat Pipes• Thermostatic Control HeatersPROPULSION • Mono-Hydrazine (76.6 kg)• Blow Down Regulation (4:1)• Passive Management Device• 5-1 Newton Thrusters ON-BOARD PROCESSING• 1750 A• 16 BIT, 1.8 MIPS, 64K SRAM & 128K PROM • 16K SUROM• RS422 & RS485 I/O• ADA• 8K Safeguard Memory (SGM)4Figure 2-13 Spacecraft Bus Characteristics - Highly Autonomous5Communications Payload : A pictorial of the communications payload is shown in Figure 2-14.6
Description of the Globalstar System GS-TR-94-0001Revision E2-21MASSCOMMUNICATIONS CHANNELS-BAND ELECTRICAL POWERTELEMETRY & COMMANDINGBeam Configuration (L - Band)• <154 kg• Each channel is 16.5 MHz with• 16 total channels• 1 channel per beam 19.38 MHz centers• ContinuouslyPayload senses SSPA input powerlevel and adjusts transmit power• Dedicated high efficiency• C-Band for command & telemetry • Telemetry 1 of 12 selectablecarriers uniformally spaced• Single command frequency with unique satellite ID• Generally Isoflux• 16 Beams• 1 - Central Beam 22.5 deg• 15 - Outer Beams to 54 degCOVERAGE (ALL BANDS & ANTENNA)• Satellite to User• Active Phased Array• 91 Elements• Frequency = 2483.5 to 2500 MHz• Max. SSPA RF 4.2 Watts• User to Satellite• Active Phased Array• 61 Elements• Frequency = 1610 to 1626.5 MHz• Scalar Horn• Bi-Polarized, 8 channels per Transmit Freq. = 6875 to 7053 MHz Rec. Freq. = 5091 to 5250 MHz• Fill subtended angle = 108 deg (with respect to satellite nadir) S-BAND TRANSMIT ANTENNAL-BAND RECEIVE ANTENNAC-BAND XMT/RECEIVE ANT. Beam Configuration (S-Band)• Generally Isoflux• 16 Beams• 1 - Central Beam Radius 16 deg• 6 - Middle Beams to 37 deg• 9 - Outer Beams to 54 deg1Figure 2-14 Communications Payload Pictorial2The communications payload is a simple bent pipe communications package as shown in Figure 2-15.3MASTER FREQUENCYGENERATORRETURN TRANSPON DERFORWARD TRANSPONDERFREQUENCY CONVERSION SECTIONFREQUENCY CONVERSION SECTIONFORWARD LINK FROM GATEWAYRETURN LINK TO GATEWAYL-C BANDC-S BANDC BAND SSPAC BAND LNAL-BAND RX ACTIVE ANTENNAS-BAND TX ACTIVE ANTENNAFORWARD LINK TO USERRETURN LINK FROM USERFile: Sat CommSAWSAWSAWSAWSWITCHSWITCHDIPLEXERTLMDIPLEXERCMD4Figure 2-15 Communications Payload Simplified Block5Function Performed : A User Terminal transmits to the satellite by L-Band. The signal enters the6satellite through the L-Band low noise amplifier. It is amplified and then converted into a C-Band signal7
Description of the Globalstar System GS-TR-94-0001Revision E2-22after which it is further amplified. This is radiated to the Gateway. The Gateway receives the signal and1block down converts to an intermediate frequency. A sample of the intermediate frequency is provided2to the TCU for processing. The communications traffic is presented to the CDMA equipment for3demodulation.4In the forward link direction, the Gateway combines the up link CDMA signals with the signal from the5command transmitter and radiates it at C-Band up to the satellite. The satellite then down converts the6signal and radiates an S-Band down link signal to the User Terminals.7Telemetry & Command : The Telemetry and Command carriers share the C-Band with the8communications feeder links. Figure 2-16 is a simplified block diagram of the T&C package on the9satellite.10ReceiverDC/DCCommandReceiverDC/DCCommand RS-422RS-422OBPEAE CMD FilterLNAsTelemetryEncoderTLM channelInsertorData (Manchester)RS-422TelemetryTransmitterDC/DCTelemetryTransmitterDC/DCTelemetryEncoderData (Manchester)OBPEFromC-BandSSPAsOutput Filter(LHCP)AE TLM FilterRS-422AE TLM AntennaCommandDecoderCommandDecoderData (NRZ-L)ClockSquelchData (NRZ-L)ClockSquelchToC-Band LNAs(LHCP)Input FilterCMD ChannelExtractorAE CMD Antenna11Figure 2-16 Satellite T&C - Compatible with Communications12The T&C connects to the normal C-Band communications antenna for on-orbit operations. There is13also a T&C antenna on the anti-earth face of the satellite. This antenna functions when the satellite is not14
Description of the Globalstar System GS-TR-94-0001Revision E2-23oriented correctly or when there are problems. The anti-earth antenna is to ensure that telemetry can be1obtained and commands entered under all recoverable contingencies. Note that the anti-earth antenna2bypasses the Low Noise Amplifier. This means that the transmitted power from the commanding earth3terminal will have to be higher than the normal power required for commanding. This can be4accommodated because there is no communications traffic when the satellite is not oriented correctly.5Yaw Steering: The satellite is steered in yaw to keep the solar panels oriented toward the sun to6extract the maximum energy. This increases the communications capacity of the Globalstar System.7There are some minor penalties that cause a slightly slower acquisition time and may cause more hand8offs than would be otherwise required.9
Description of the Globalstar System GS-TR-94-0001Revision E2-24This page intentionally left blank.12
Description of the Globalstar System GS-TR-94-0001Revision E3-13. FREQUENCIES AND COVERAGE ANALYSIS13.1 Frequency Plans2Globalstar uses C-Band between the Gateway and the Satellites as shown in Figure 3-1.35250 MHz91113158 3 7 512 14 16 10 1 6 4 2CmdLHCPS-Band2500 MHz2483.5 MHz5091 MHzLHCP16.5 MHz 19.38 MHzRHCP16.5 MHz16 BEAMS159 MHzTO USER TERMINALSatellite Transponder7055 MHzLHCPL-Band6875 MHzLHCP180 MHzTO GATEWAY16.5 MHz1610 MHz 1626.5 MHzTLMSatellite TransponderRHCP31513115 9 71681046 14212BeamBeamBeamX1 X2 X3 X4 X5 X6 X7 X8 ChannelY1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 ChannelX1 X2 X3 X4 X5 X6 X7 X8Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8ChannelFROM GATE WAY FROM UTFile: Freq Plan14Figure 3-1 Frequency Plan - Emphasizes Conservation of Spectrum5The C-Band antennas on the satellite use an earth coverage beam. The Gateways use a parabolic6antenna and program track the satellites. Program tracking uses the orbital data provided by the7Satellite Operation Control Center to position the Gateway antenna.8Efficient Spectrum Utilization - The spectrum is used efficiently by incorporating frequency9reuse and spread spectrum into the design. Both Right Hand Circular Polarization (RHCP) and10Left Hand Circular Polarization (LHCP) are used for C-Band. This allows 8 frequencies to11
Description of the Globalstar System GS-TR-94-0001Revision E3-2connect to 16 beams on the satellite. The beam numbers shown in Figure 3-1 map to the S-Band1beams shown in Figure 3-2 and the L-Band beams in Figure 3-3 which follows. The alpha2characters used within the spectrum blocks and on the following diagram indicate polarization.3X= Left Hand Circular Polarization4Y= Right Hand Circular Polarization53.2 Satellite Antenna Beam Configuration6The S-Band antennas on the satellite are configured to produce 16 beams as shown in Figure 3-72.889101112131415161234567+Xsc+YscY5Y1X4Y2X1Y3X2Y4X3X5X8Y6X7 Y8X6Y7File: S-BeamsChannel Assignments Beam AssignmentsView from SatelliteX= LHCPY=RHCPLooking at Earth Nadir9Figure 3-2 S - Band Beams10The antennas are multiple beam antennas designed to provide an isoflux pattern on the earth in11the service region. The isoflux pattern is obtained by shaping the beam so that the gain at the12edge of coverage is higher than at the beam center. This compensates for the difference in losses13due to the longer slant range at the beam edges.14
Description of the Globalstar System GS-TR-94-0001Revision E3-3L-Band Pattern: The L-Band pattern consists of 16 beams. Beam 1 is in the center. The1remaining 15 beams are arranged in an annular ring around the center beam as shown in Figure23-3.389101112131415161234567+Xsc+YscY5Y1X4Y2X1Y3X2Y4X3X5X8Y6X7 Y8X6Y7File: L-BeamsChannel Assignments Beam AssignmentsView from SatelliteX= LHCPY=RHCPLooking at Earth Nadir4Figure 3-3 L- Band Beams5This configuration provides better coverage on the earth to reduce the power requirements on the6L-Band transmitters in the User Terminals.7
Description of the Globalstar System GS-TR-94-0001Revision E3-4Efficient Spectrum Utilization - As shown in Figure 3-4 and Figure 3-5, only 16.5 MHz of L-1Band and S-Band spectrum are used. The same set of frequencies are reused in each of the 162beams. Note that C-Band frequencies are assigned to beams to minimize interference. The3Globalstar approach is very efficient in its use of the valuable L-Band and S-Band spectrum. L-4Band is used to communicate from the User Terminal to the satellite and S-Band is used to5communicate from the Satellite to the User Terminal. Within each of the beams, there are 136FDM channels.71.23 MH z 1.23 MHz 1.23 MHz 1.23 MHz 1. 23 M H z 1.23 MH z 1.23 MH z1626.5 MHz162 5.490 MH z1610.0 MHz730 kHz1624.260 MHz162 3. 030 MH z1621.800 MHz1 620 .5 70 MHz1619.340 MHz1 618.110 MHz1616.880 MHz1 615 .6 50 MHz1614.420 MHz1613.190 MHz161 1.960 MH z16 10 .7 30 MHz 16.5 MHz File: L-Band1010 kHz123456789101112138Figure 3-4 L - Band Channel9Frequencies102500.0 MHz24 99. 15 0 MHz2 483 .5 M H z249 7. 920 MH z2 496 .6 90 MHz249 5.460 MH z249 4. 230 M H z2 493 .0 00 MHz2491.770 MHz2 490.5 40 MHz248 9. 310 MH z2 488 .0 80 MHz2486.85 0 MHz2 485.6 20 MHz24 84. 39 0 MHz1.23 MH z 1.23 MHz 1.23 MHz 1.23 MHz 1. 23 M H z 1.23 MH z 1.23 MH z89 0 kHz 16.5 MHz File:S-Band850 kH z1234567891011121311Figure 3-5 S - Band Channel Frequencies12Spectrum Sharing - Within a channel, spread spectrum is used to convey the voice or data13intelligence. Multiple voice or data circuits may be carried within a single 1.23 MHz FDM14channel. The circuit data is separated by unique PN spreading sequences. This allows the same15spectrum to be shared by other CDMA users.16
Description of the Globalstar System GS-TR-94-0001Revision E3-5Satellite Frequency Plan: Table 3-1 illustrates how the C-Band up link signals are converted1to S-Band down link signals and indicates how the signals are connected to down link beams.2The table shows the assigned C-Band Frequencies.3Table 3-1 Satellite C-Band to S-Band4C-Band Frequencies S-Band LHCP S-Band RHCPRF Freq.(MHz) L.O. Freq (MHz) Chan Beam Chan Beam5105.21 7596.96 X1 12 Y1 95124.59 7616.34 X2 14 Y2 115143.97 7635.72 X3 16 Y3 135163.35 7655.10 X4 10 Y4 155182.73 7674.48 X5 1 Y5 85202.11 7693.86 X6 6 Y6 35221.49 7713.24 X7 4 Y7 75240.87 7732.62 X8 2 Y8 55091.50 CMD5Table 3-2 illustrates the how the Return link is processed in the Satellite. The table shows the6assigned C-Band Frequencies.7Table 3-2 Satellite L-Band to C-Band8L-Band to C-Band L-Band LHCP L-Band RHCPRF Freq(MHz) L.O. Freq (MHz) Chan Beam Chan Beam6908.99 5290.74 X1 8 Y1 36928.37 5310.12 X2 10 Y2 156947.75 5329.50 X3 4 Y3 136967.13 5348.88 X4 6 Y4 116986.51 5368.26 X5 1 Y5 57005.89 5387.64 X6 14 Y6 97025.27 5407.02 X7 2 Y7 77044.65 5426.40 X8 12 Y8 166876.0-6877.1 (12 ea.) TLM910
Description of the Globalstar System GS-TR-94-0001Revision E3-6Command and Telemetry Frequencies: The telemetry frequencies are listed in Table 3-31Table 3-3 Satellite Telemetry & Command Frequencies23CommandChannel No. of Channel FrequencyBandwidth Channels Width(s) Center(s)5091 to 1 240 KHz 5091.55092 (*)TelemetryChannel No. of Chnl Channel FrequencyBandwidth Channels No. Width(s) Center(s)6875.95 to 12 1 100 KHz 6876.06877.15 2 6876.13 6876.24 6876.35 6876.46 6876.57 6876.68 6876.79 6876.810 6876.911 6877.012 6877.14Doppler: The Frequencies that appear at the Globalstar nodes (Gateway, Satellite, UT) differ5from the assigned frequencies. Doppler is one of the primary contributors. Doppler can be6computed and the nodes can compensate for the differences in frequency. Table 3-4 indicates7the magnitude of the Doppler components.8Table 3-4 Worst Case Doppler9Frequency Doppler RatePath Name From To (MHz) (KHz) Hz/secForward Uplink Gateway Satellite 5250 97.2 468.8Fwd Downlink Satellite UT 2500 46.5 224.3Return Uplink UT Satellite 1626.5 30.2 146.0Return Downlink Satellite Gateway 7052.9 131.6 634.9
Description of the Globalstar System GS-TR-94-0001Revision E3-73.3 Earth Surface Coverage1The surface of the earth, with the exception of the polar regions, is covered with multiple2overlapping satellite beams as shown in Figure 3-6.34Figure 3-6 Full Earth Coverage-Except Polar Regions5The contours shown indicate that a User Terminal within the contour can communicate with the6satellite at an elevation angle above 10 degrees.7Constraining the User Terminals to operate with satellites that have higher elevation angles8referred to the User Terminal will reduce the overlapping coverage but would provide an9advantage in that it would reduce the power demands placed on the User Terminal to close the10link. This would result in longer battery life for the User Terminal.11Conversely, lowering the angle to the satellite will increase the overlapping coverage. Small12changes dramatically increase the coverage area. This is particularly apparent in the polar13regions. If operated at low elevation angles, polar areas that otherwise could not be covered can14
Description of the Globalstar System GS-TR-94-0001Revision E3-8receive service. In polar areas, overlapping coverage would be increased and power demands1may be increased. In this region the look angle to the satellite is limited. High gain directional2antennas become practical for fixed and even portable installations. The pay back is that3Globalstar could now serve areas that otherwise might be unserviceable.4To a degree, some of these same considerations discussed for polar areas apply to equatorial5areas where the overlapping coverage is less than 100%.6Satellites in View as a Function of Latitude: Figure 3-7 illustrates the multiple satellite7coverage more clearly.8100.090.080.070.060.050.040.030.020.010.00.00 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90Multiple Satellite Coverage Versus Latitude(10 degree elevation angle, 48 satellite constellation)USA (CONUS)CENTRALEUROPE SCANDINAVIAAUSTRALIALatitude% of Time1 or more2 or more3 or more4 or more94080619Figure 3-7 Enhanced Coverage for Temperate Regions10Note that the coverage is optimized to provide multiple coverage in the temperate regions. In11areas within this temperate region, the User Terminal can communicate via multiple satellites.12This enhances the link availability and allows the User Terminal to operate with nominal link13margins.14
Description of the Globalstar System GS-TR-94-0001Revision E3-9Orbital Parameters: The orbital parameters for the initial injection orbit and for the final on1station orbit are shown in Figure 3-8.2On Station Phasing OrbitRAAN Spacing for plane J=1...8 (Degrees) +/- 1.045Relative Phasing between adjacent planes (Degrees) +/- 17.5Parameter Tol (3 )Mean Tol (3 )MeanRadius (km) +/- 0.17778 +/- 207298Orbit Period-Nodal +/- 0.13 sec114 min +/-0.4103.35Inclination (Degrees) +/- 0.0152 +/- 0.652Eccentricity + 0.0080.000 + 0.010.000+/- 160Relative Phasing between satellites in a plane (Degrees)Fi le: O r bi tp Rev 11 /0 6/963Figure 3-8 Orbital Parameters for Globalstar Satellites4Supplementary Coverage: There are two problem areas in the coverage.51. One is over the equator where the beam is narrow. There has been some study of using some6additional satellites to cover the equatorial area. At this point in time, this is not financially7justified. If more business is identified as we penetrate Indonesia, the Philippines, India,8Central Africa, and Central America enhanced coverage may be examined again.92. The second area that is not covered well is the polar area. Some study of supplementing10coverage with Molniya orbit satellites has been performed. This type of orbit “hangs” in the11polar areas for a long period and then orbits over the south polar area very rapidly. If12coverage of the northern areas becomes economically justified, this may be re-visited.13The other thing to be considered in northern areas, such as the islands north of mainland Russia,14is the inclination of the satellites. They do not go beyond 52 degrees north. This means a fixed15UT antenna can be pointed south only. Gain can be obtained due to the directivity. Fixed User16Terminals could operate much further north if they do not require an omni-directional Fixed17User Terminal antenna.18
Description of the Globalstar System GS-TR-94-0001Revision E3-103.4 Position Determination1The location of the User Terminal is determined by Globalstar and used for several purposes.2Any position location services that may be provided should be considered a by product of the3Globalstar System. The primary purpose of Globalstar is to provide communications. It should4not be considered as a competitor or replacement for GPS or GLONASS. Two basic accuracy5are supported.6Low Accuracy: The user terminal is located to within 10 km for purposes of National7Sovereignty, to assign the user to a gateway, and to support registration. This accuracy is8sufficient for the gateway to determine which satellite/beam should be used for phone9paging. This avoids having to page on multiple satellites/beams at the cost of capacity.10High Accuracy: A higher accuracy on the order of 300 meters is feasible in under some11conditions. This may be attractive as a service. This high accuracy results from the high12degree of precision with which the position and velocity of the satellite constellation is13know. Each satellite incorporates a GPS receiver to determine position and rate of14change of position. When this data is processed with other data at the SOCC the15precision of the orbit becomes quite good. The CDMA, for its own purposes, needs to16align chips within 1/8 of a chip. Potential for high positioning accuracy is inherent.17The User Terminal may determine its position with the assistance of the Gateway or it may18determine its position autonomously. In all cases, determination of position is based on19determining the intersection of three or more spheres in 3-dimensional space. The surface of the20earth can be used as one of the spheres. The Gateway has the processing power to make active21determination attractive. This must be traded for additional messaging that will be required to22support active determination of position.23Active Determination: The Gateway calculates range based on time delay between the24User Terminal and the Gateway through a satellite. The phone transmission can be an25access probe or an ongoing call, but it must be synchronized in some fashion to the26forward link signal. When this accomplished through two satellites with the proper27geometry, excellent positioning accuracy can be achieved.28Passive Determination: The User Terminal can determine its location without the29assistance of the Gateway. In this mode, since time is not known very well this means30the system has an extra degree of freedom. The phone measures a T between two31different satellites, and another T using a third satellite. Three 3 satellites are required,32to solve for the phone's clock offset. An additional form of passive position33determination incorporates measurements of the satellite velocities relative to the phone,34instead of or in addition to the satellite ranges to the phone. This is done by measuring35the received Doppler shift of the satellite signal.36
Description of the Globalstar System GS-TR-94-0001Revision E3-11Any of the techniques must incorporate the following generic considerations.1Geometric Dilution Of Precision (GDOP): This is a phenomenon that affects all2forms of position determination. It is due to the orientation of the satellites from the3phone's perspective. When the geometry is good, precision is good. When poor, the4accuracy degrades very quickly.5Time to Position: Time to achieve an accurate position depends on the time. In simple6forms, the more time the more precise the location.7Geographical Constraints: Position determination becomes more difficult when the8User Terminals are on the equator or at high latitudes. In these cases, only one satellite9may be visible. This means that range must be determined at one point in time and the10range determined again at another point in time. Under these conditions the geometry is11less than optimal, resulting in a long time to achieve a valid position determination and12an inaccurate determination of position.13Terrain Maps: For the surface of the earth to be used as one of the intersecting spheres,14a terrain map must be used to determine altitude above the mean surface of the earth.15The degree of granularity of this map will impact the accuracy that can be achieved and16will impact the time to achieve a position indication.17
Description of the Globalstar System GS-TR-94-0001Revision E3-123.5 Channel Characteristics1Figure 3-9 illustrates the orientation of a User Terminal in a typical temperate climate scenario2with multiple satellite coverage.3Channel 5COMBINERRECEIVER 1RECEIVER 2RECEIVER 3Globalstar HandsetGlobalstar GatewayS1 S1 S2 S2Globalstar 1 Globalstar 2Channel 5Decoder&Vocoder4Figure 3-9 Channel Characteristics Considerations5Line of Sight: For the Globalstar system, many of the obstructions in the direct line of sight do6not completely block the line of sight, but rather simply attenuate the signal. Given two7satellites in view at the same time, the probability of signal blockage or shadowing to both8satellites is significantly less than the probability of blockage to a single satellite.9
Description of the Globalstar System GS-TR-94-0001Revision E3-13Specular Reflection: The specular reflection component is the signal reflected off the surface1of the earth. The magnitude of the reflected signal can be large if the surface is relatively smooth2and flat at the point of reflection. The specular component will prove to be an insidious problem3for the hand held antennas. It can either add to or subtract from the signal received from the4direct line of sight. This problem can be managed effectively for the mobile and the fixed5station antennas.6Diffuse Reflection: The diffuse component is composed of a sum of a large number of7individual terrain scatter from outside the first Fresnel zone. This diffuse component is8characterized by phase incoherent multi-path with a uniform phase distribution and a Rayleigh9amplitude distribution. The signal fading associated with the diffuse component combining with10the direct component produces the fast-fading characteristics of the propagation channel.11Building Penetration: Globalstar has limited ability to penetrate buildings. Operation is12possible in wood frame buildings or near windows with a wide angle view of the sky. The best13locations within building results in 6 to 13 dB added insertion loss. There is a high degree of14sensitivity to antenna location within the building. A change in lateral position of 20 to1530 centimeters can produce a 30-dB variation in signal power.16In Pocket: With the antenna extended, operation depends on orientation. Body blockage can17insert attenuation in excess of 15 dB. If the antenna is stowed, operation is not considered18feasible.19Interference: User Terminal receivers may experience interference when operating in close20proximity to microwave ovens, plywood plants or hospitals. The transmitters are frequency21coordinated for operation with Radio Astronomy sites, for operation with GPS, and with22GLONASS. The Gateway site locations are selected to avoid interference with the Microwave23Landing Systems (MLS) associated with airports.24Conclusions: Several Conclusions can be drawn for Globalstar operations.251. Operation at higher elevation angles is preferred.262. Mobile will suffer less from specular. Power control may be less effective at some27operating speeds.283. Fixed terminals will suffer less degradation from all sources.294. Forward and Return link behavior are not correlated. Conclusions from one direction30cannot be used to derive control information for the other direction.31
Description of the Globalstar System GS-TR-94-0001Revision E3-143.6 Link Analysis1The Globalstar system provides spatial diversity to overcome shadowing and blocking. The link2analysis in this section is based on the current FCC filing which assumes nominal 5.5 meter3antennas at the Gateways. There are 3 cases that are presented.4Case 1: This is a detailed link budget. This case considers the forward and return links between5the Gateway to the User Terminal. The up link from the Gateway to the satellite is C-Band. The6down link from the satellite to the User Terminal is S-Band. The Return Link is L-Band from7the User Terminal to the Satellite and C-Band from the satellite to the Gateway. There is no8shadowing or blocking and diversity is used.9Case 2: This is an abbreviated link budget that shows only the differences from case 1. One10path is blocked. Only the C-Band or the S-Band can be blocked; since, the Gateway will be in11one location.12Case 3: This is a rare case where both links are shadowed or faded by 10 dB.13Table 3-5 Forward Link C-Band - Case 1 - Detailed Budget14Up Link Gateway to Satellite C-BandFrequency 5125.0 MHzNominal EIRP per user 26.8 dBWPath loss(40 degree. GW elev.) -172.5 dBPolarization & Tracking. Loss -1.1 dBSatellite Antenna gain (incl. line loss) 3.1 dBReceive power/user at LNA -143.7 dBWAverage User Data Rate 2400.0 b/sSystem Noise Temperature 549.5 KThermal Noise Density, No -201.2 dBW/HzEstimate Interference Density -198.5 dBW/HzUp link Eb/(No+Io) 19.1 dB15
Description of the Globalstar System GS-TR-94-0001Revision E3-15Table 3-6 Forward Link S-Band - Case 1 - Detailed Budget1Down Link Satellite to User TerminalFrequency 2495.0 MHzNominal EIRP per user -2.9 dBWiSatellite Altitude 1414.0 kmTypical Elevation Angle 50.0 degreesRange 1740.5 kmFree Space Loss -165.2 dBPolarization & Tracking. Loss -1.0 dBShadowing Loss 0.0 dBReceive Signal Strength /user/sat. -169.1 dBWiUser Antenna Gain(incl. line loss) 2.6 dBiUser Signal at antenna output -166.5 dBWSystem Noise Temperature 293.7 KThermal Noise Density, No -203.9 dBW/HzAverage Data Rate, Rb 2400.0 b/sDown link Eb/No 3.6 dBInterference per Channel -148.6 dBWSpreading Bandwidth 1.23 MHz-10*log(spreading BW) -60.9 dB/HzInterference Density, Io -209.5 dBW/HzDown link Eb/(No+Io) 2.6 dBCoherent combining gain 2.5 dBOverall Eb/(No+Io) (up&dn) 5.0 dBOperating Eb/No 5.0 dB23
Description of the Globalstar System GS-TR-94-0001Revision E3-16Table 3-7 Forward Link - Case 2 - Link Blockage1C-Band Up Link and S-Band Down LinkUp linkEIRP per user 28.8 dBWUp link Eb/(No+Io) 21.1 dBDown linkEIRP per user -0.4 dBWDown link Eb/(No+Io) 5.1 dBCoherent combining gain 0.0 dBOverall Eb/(No+Io) 5.0 dB2Table 3-8 Forward Link - Case 3 - Rare Two Link Fade3C-Band Up Link and S-Band Down LinkUp linkEIRP per user 36.3 dBWUp link Eb/(No+Io) 28.6 dBDown linkEIRP per user 7.1 dBWShadowing loss -10.0 dBDown link Eb/(No+Io) 2.6 dBCoherent combining gain 2.5 dBOverall Eb/(No+Io) 5.0 dB4
Description of the Globalstar System GS-TR-94-0001Revision E3-17Table 3-9 Return Link L-Band - Case 1 - Detailed Budget1Up Link User Terminal to SatelliteFrequency 1615.0 MHzNominal EIRP per user -11.2 dBWiSatellite Altitude 1414.0 kmTypical elevation angle 70.0 degreesRange 1487.1 kmFree Space Loss -160.1 dBPolarization & Tracking. Loss -1.0 dBShadowing loss 0.0 dBS/C Receive Signal Strength -172.3 dBWiS/C Antenna Gain (incl. line loss) 11.5 dBiUser Signal at antenna output -160.8 dBWSystem Noise Temperature 500.0 KThermal Noise Density, No -201.6 dBW/HzAverage data rate, Rb 2400.0 b/sUp link Eb/No 7.0 dBInterference per channel -142.2 dBWSpreading bandwidth 1.23 MHzInterference Density -203.1 dBW/HzUp link Eb/(No+Io) 4.7 dB2
Description of the Globalstar System GS-TR-94-0001Revision E3-18Table 3-10 Return Link C-Band - Case 1 - Detailed Budget1Down Link Satellite to GatewayFrequency 6975.0 MHzNominal EIRP per user -27.7 dBWPath loss (40 degree GW elev.) -175.2 dBPolarization & Tracking. loss -1.1 dBGW antenna gain 49.4 dBReceive power/user -154.5 dBWSystem noise temp. 127.7 KThermal noise density, No -207.5 dBW/HzInterference Density, Io -212.3 dBW/HzDown link Eb/(No+Io) 18.0 dBCombining gain 1.8 dBOverall Eb/(No+Io)(up&dn) 6.3 dBOperating Eb/No 6.3 dB2Table 3-11 Return Link - Case 2 - Link Blockage3L-Band Up Link and C- Band Down LinkUp linkEIRP per user -9.4 dBWUp link Eb/(No+Io) 6.5 dBDown linkEIRP per user -25.9 dBWDown link Eb/(No+Io) 19.8 dBCombining gain 0.0 dBOverall Eb/(No+Io)(up&dn) 6.3 dB
Description of the Globalstar System GS-TR-94-0001Revision E3-191Table 3-12 Return Link - Case 3 - Rare Two Link Fade2L- Band Up Link and C- Band Down LinkUp linkEIRP per user -1.2 dBWShadowing loss -10.0 dBUp link Eb/(No+Io) 4.7 dBDown linkEIRP per user -27.7 dBWDown link Eb/(No+Io) 18.0 dBWCombining gain 1.8 dBOverall Eb/(No+Io)(up&dn) 6.3 dB3Forward Link: The link from the Gateway to the User Terminal reduces self interference4within an FDM channel by coherent transmissions and by using CDMA Walsh codes which are5orthogonal.6Return Link: The Return link uses paths through multiple satellites to combat the effects of7shadowing, blockage and multi-path.8
Description of the Globalstar System GS-TR-94-0001Revision E3-20This page intentionally left blank.12
Description of the Globalstar System GS-TR-94-0001Revision E4-14. CODE DIVISION MULTIPLE ACCESS (CDMA)14.1 Introduction2The Globalstar Air Interface uses a modified form of IS-95 to support Code Division Multiple Access.3CDMA was selected for Globalstar because it represents a proven technology that can provide a4bandwidth efficient modulation scheme for satellite communications. It is relatively interference tolerant,5both from the standpoint of generation of interference to other services and tolerating outside6interference. As a bonus, there is a level of security inherent in the modulation scheme. It is difficult to7listen into conversations or to pirate services from the system. CDMA is able to provide good voice8quality while operating at relatively low RF power levels. The Globalstar CDMA is based on the9existing QUALCOMM CDMA product line used for terrestrial cellular communications.10Path Diversity combats fades and blockage - Probably one of the most important aspects of11CDMA is associated with the way Globalstar uses CDMA. Diversity combining is used to provide12continuous communications even under conditions where a path to one satellite is totally blocked. The13Globalstar system can operate with relatively low link margins and still provide a high link availability.14CDMA supports spectrum sharing - There are other useful and interesting aspects of CDMA. In15CDMA two or more systems can occupy the same frequency-power space. Separation of the16intelligence is accomplished by demodulating the PN spreading sequence. This supports band sharing17by more than one system.18Soft Capacity Limit: There is another useful aspect of CDMA. Since CDMA is basically a system19whose capacity is limited by self generated interference, the limit is a soft limit. Unlike bandwidth limited20systems like Time Division Multiple Access (TDMA) or Frequency Division Multiple Access (FDMA),21CDMA allows the predicted capacity limit to be exceeded with soft degradation occurring.22
Description of the Globalstar System GS-TR-94-0001Revision E4-24.2 Diversity Combining1Diversity combining is used to mitigate the effects of link phenomena. In a simple form, diversity2combining uses the signal with the best signal to noise ratio. Rake receivers are used to receive and3combine the signals from multiple sources. As an example, the User Terminal will provide diversity4combining for the forward link signals received through up to two different links simultaneously.5Diversity increases Availability - The performance in the diversity mode will always exceed the6performance that would be achieved with communications via a single string link. Diversity combining is7continuous. There is no break in service if one or more of the diversity links is lost.8Multiple Satellite - Forward Link: In the forward direction, the use of diversity brings substantial9gain if one of the satellites is obstructed and is break even for unobstructed operation without multi-path.10With multi-path fading (typically with high values of Ricean k) the diversity also provides benefit.11Multiple Satellite - Return Link: In the reverse direction, there is a clear advantage because gain12results even with no obstruction. Because this is non coherent diversity combining, the gain is not quite13as much as with coherent operation.14Multiple Beam - Forward Link: There is no diversity advantage for using multiple beams. All beams15come from precisely the same point in the sky and are at the same sub-channel frequency. Whatever16shadowing or multi-path occurs for one beam occurs for the other.17Multiple Beam - Return Link: On the Return Channel the signals the gateway sees through the18different beams are, of course, the same; they fade in exactly the same way. But the noise backgrounds19in which they are received are essentially independent. There is some advantage to using diversity.204.3 Fade Mitigation21The Gateway will support power control to address slow fades and interleaving to address medium to22fast fades. Power control is implemented on both the forward and return links.23Power Control: To support forward link power control, the user terminal reports pilot quality statistics24to the gateway. For return link power control, the Gateway measures frame error rate. The response25time of the power control is adjusted to accommodate the satellite round trip time delays. Average26round trip delay is on the order of 30 ms.27Forward Link: Forward link power control is closed loop under control of the Gateway. The28dynamic range of the forward link power control is at least 20 dB.29Return Link: The return link is operated open loop when a fade is first sensed, then closed30loop under control of the Gateway. The dynamic range of the return link power control is a31
Description of a Globalstar Gateway GS-TR-94-0001Revision E4-3maximum of 20 dB with a 0.5 dB step size. The User Terminal will limit the integrated1transmitted power to conform with regulatory requirements.2Interleaver: The Interleavers will operate over a 20 ms vocoder packet frame which will effectively3address medium and fast fades.44.4 Acquisition5Search to Acquire: When a Globalstar phone hunts for a pilot channel it must search through a multi-6dimensional space. Three of the more obvious dimensions are illustrated in Figure 4-1.7PN CodeFrequency DopplerPN Timing8Figure 4-1 Acquisition Search Space9The goal is to reduce the search volumes by all means practical. Given that the search volume is10decreased; then parallel processing can be used to speed the search process without compromise to the11probability of a correct acquisition.12
Description of the Globalstar System GS-TR-94-0001Revision E4-4Latitude Dependence: The acquisition time is also a function of other variables such as latitude as1shown in Figure 4-2.201234560 2 0 4 0 6 0Latitu d e (deg)Time (secs)PPS Me anPPS 95% 3Figure 4-2 Acquisition Time as a function of Latitude4The Search is latitude dependent due to the orbital geometry. Less satellites are visible at high latitudes.5Several approaches are used to attain this apparent rapid response. Parallel searching speeds the6search process materially. The Ground Operations Control Center (GOCC) is also involved in speed7up of the search process. The search times shown in Figure 4-2 apply if the pilot frequency is known.8The GOCC can help by assigning the pilot frequencies near the center of the band in a given9geographical area. This basically collapses the search frequency dimension shown in Figure 4-1 to the10uncertainty due to Doppler.11Summary: This means that if the User Terminal stays in its home gateway area the acquisition process12can be very quick. If the pilot frequency is unknown due either to poor assignment by the GOCC or13due to the User Terminal roaming to another gateway area, the search time can extend. Basically the14maximum search time is the number of pilots that must be searched times the time to acquire as shown in15Figure 4-2. The mean time to acquire is roughly half of the maximum time to acquire.16
Description of a Globalstar Gateway GS-TR-94-0001Revision E4-54.5 Forward CDMA Channel1An example assignment of the code channels transmitted by a gateway is shown in Figure 4-3. Out of2the 128 code channels available for use, the example depicts the Pilot Channel (always required), one3Sync Channel, seven Paging Channels (the maximum number allowed), and 119 Traffic Channels of4Rate Set 1. Another possible configuration could replace all the Paging Channels and the Sync Channel5one for one with Traffic Channels of Rate Set 1, for a maximum of one Pilot Channel, zero Paging6Channels, zero Sync Channels, and 127 Traffic Channels of Rate Set 1.7Pilot ChanPaging Ch 1Paging Ch 7Sync ChanTraffic Ch 1• • •Up toFORWARD CDMA CHANNEL (1.23 MHz channel transmitted by gateway)Traffic Ch 119Traffic Ch N• • •Up toPower Control Sub-ChannelTraffic Data•••••••••••••••8Figure 4-3 Forward CDMA Channel Transmitted by a Gateway9The forward CDMA channel consists of the Pilot Channel, one Sync Channel, up to seven Paging10Channels, and a number of Forward Traffic Channels. Multiple Forward Channels are used in a11Gateway by placing each Forward Channel on a different frequency.12
Description of the Globalstar System GS-TR-94-0001Revision E4-6The forward link Pilot, Sync and Paging Channel is generated as shown in Figure 4-4.1Convolutional Encoder r=1/2 K=9Paging Channel BitsCode SymbolWalsh Function pPN Chip, 1.2288 McpsDecimatorLong Code GeneratorLong Code Mask for Paging Channel k4.8 kbps 2.4 kbpsSync Channel BitsPilot Channel (All 0's)Walsh Function 0 or 1PN Chip, 1.2288 McpsBlock InterleaverModulation Symbol9.6 ksps 4.8 ksps9.6 kspsConvolutional Encoder r=1/2 K=9Code SymbolSymbol RepetitionModulation SymbolWalsh Function 32 or 33PN Chip, 1.2288 Mcps1.2 kbps Block InterleaverModulation Symbol4.8 ksps2.4 ksps 4.8 ksps9.6 ksps1.2288 McpsAAASymbol RepetitionModulation Symbol9.6 ksps2Figure 4-4 Forward Link Pilot, Sync and Paging Channel3The forward link is modulated as follows.4Pilot Channel: The Pilot Channel is transmitted continuously by the Gateway and is utilized by the5User Terminals operating within the coverage area of the Gateway to acquire timing on the forward6channel, to provide a phase reference for coherent demodulation and to provide signal strength7comparisons that govern when to do hand offs. The Pilot channel will generate an all zeros Walsh8Code. This is combined with the short code used to separate signals from different Gateways and9different satellites. The pilot channel is modulo 2 added to the 1.2288 Mc/s short code and is then10QPSK spread across the 1.23 MHz CDMA bandwidth. The User Terminal monitors the pilot channel11and assesses its signal strength at all times except when it is operating in the slotted mode.12Sync channel: The Sync Channel is an encoded, interleaved, spread and modulated spread spectrum13signal that is used by the User Terminals operating within the gateway coverage area to acquire initial14time synchronization. The Sync channel will generate a 1200 b/s data stream that includes (1) time, (2)15transmitting Gateway identification, (3) assigned paging channel. This is convolutionally encoded and16Block Interleaved to combat fast fades. The resulting 4800 symbols per second data stream is modulo17two added to the sync Walsh code at 1.2288 Mc/s and the short code. It is then QPSK spread across18the 1.23 MHz CDMA bandwidth.19
Description of a Globalstar Gateway GS-TR-94-0001Revision E4-7Paging Channel: The Paging Channel is used for transmission of control information and pages from a1gateway to a user terminal. The paging channel is convolutionally encoded at Rate = 1/2, Constraint2length K = 9 and block interleaved. The resulting symbol rate is combined with the long code. The3paging channel and the long code are modulo two added and provided to the symbol cover where the4resulting signal is modulo two added to the 1.2288 Mc/s Walsh Code and the short code. The results5are then QPSK spread across the 1.23 MHz CDMA bandwidth.6Forward Traffic Channel: The Forward Link Traffic Channel - Rate Set 1 is generated as shown in7Figure 4-5.84.8 kbps 2.4 kbps 0 kbpsConvolutional Encoder r=1/2 K=9Forward Traffic Channel Information Bits for User i with Rate Set 1 (79, 32, or 0 bits/frame)Code SymbolBlock InterleaverAdd 8-bit Encoder TailAdd Frame Quality Indica-tors (8 , 7, or 0 bits/frame)3.95 kbps 1.6 kbps 0 kbpsSymbol RepetitionModulation SymbolModulation Symbol9.6 ksps 0 kspsPower Control Bits50 bpsMUX50 HzPN Chip, 1.2288 Mcps9.6 ksps 0 ksps9.6 ksps 4.8 ksps 0 kspsDecimatorLong Code GeneratorLong Code Mask for User i9.6 ksps1.2288 McpsDecimatorWalsh Function jAAdd Reserved Bit (1, 1, or 0 bits/frame)4.0 kbps 1.65 kbps 0 kbps4.4 kbps 2.0 kbps 0 kbps9Figure 4-5 Forward Link Traffic Channel - Rate Set 110
Description of the Globalstar System GS-TR-94-0001Revision E4-8The Forward Link Traffic Channel - Rate Set 2 is generated as shown in Figure 4-6.19.6 kbps 4.8 kbps 2.4 kbps 0 kbpsConvolutional Encoder r=1/2 K=9Forward Traffic Channel Information Bits for User m with Rate Set 2 (171, 79, 32, or 0 bits/frame)Code SymbolBlock InterleaverAdd 8-bit Encoder TailAdd Frame Quality Indicators (12, 8 , 7, or 0 bits/frame)8.55 kbps 3.95 kbps 1.6 kbps 0 kbpsSymbol RepetitionModulation SymbolModulation Symbol19.2 ksps 0 kspsPower Control Bits50 bpsMUX50 HzPN Chip, 1.2288 Mcps19.2 ksps 0 ksps19.2 ksps 9.6 ksps 4.8 ksps 0 kspsDecimatorLong Code GeneratorLong Code Mask for User m19.2 ksps1.2288 McpsDecimatorWalsh Function nAAdd Reserved Bit (1, 1, 1, or 0 bits/frame)8.6 kbps 4.0 kbps 1.65 kbps 0 kbps9.2 kbps 4.4 kbps 2.0 kbps 0 kbps2Figure 4-6 Forward Link Traffic Channel - Rate Set 23The Vocoder encodes the voice into a PCM data stream. The data stream is the processed as shown4in Figure 4-5. The resulting data stream is then power controlled and modulo two added to the 1.22885Mc/s Walsh code and the short code. The results is then QPSK Spread across the 1.23 MHz CDMA6communication channel bandwidth. The Globalstar Air Interface will support two different rate sets7from the Gateway. Within a rate set, the Globalstar Air Interface (GAI) will support variable data rate8operation. When the high rate shown in Figure 4-5 is used, two Walsh codes are required.9
Description of a Globalstar Gateway GS-TR-94-0001Revision E4-9Modulation and Spreading: Modulation and spreading is applied as shown in Figure 4-7.1AQ(t)I(t)Baseband FilterBaseband FilterI-Channel Inner PN Sequence 1.2288 Mcps Q-Channel Inner PN Sequence 1.2288 McpsIQcos (2šfct)sin (2šfct)Σs(t)Outer PN Sequence GeneratorDOuter PN Chip1.2 kcps1 Outer PN Chip Delay = 833.333 µs2Figure 4-7 Forward Link Modulation and Spreading3The spreading sequence structure for a given Globalstar CDMA channel is comprised of an inner PN4sequence pair and a single outer PN sequence. The inner PN sequence has a chip rate of 1.2288 Mcps5and a length of 1024, while the outer PN sequence has an outer chip rate of 1200 outer chips per6second and a length of 288; the outer PN sequence modulates the inner PN sequence to produce the7actual spreading sequence, lasting exactly 240 msec. Exactly one inner PN period is contained within a8single outer PN chip. The spreading and modulation process applies to all forward link channels.9Path Identification: It is necessary to know the path that a signal has taken in order to facilitate10gateway sharing of a forward CDMA channel and to support diversity combining. Path information is11derived from the pilot signal.12Gateway: Two gateways can share a forward CDMA channel. Pilot channel 0 is assigned to13the first gateway can be allocated more power and serve as a beacon pilot within the beam to14increase acquisition speed of the User Terminals in the beam.15Orbital Plane: The inner PN sequence is used to identify the orbital plane. The length of the16sequence is 2 10 chips at a chip rate of 1.2288 mcps. there are 24 repetitions every 20 ms.17Satellite: Each satellite is identified by a pilot PN sequence.18Beam: Each Satellite Beam has a unique outer PN sequence offset.19
Description of the Globalstar System GS-TR-94-0001Revision E4-10Beam Juxtaposition: Each Adjacent beam within a satellite is identified by a unique inner PN1sequence offset. Inner PN offsets are reused among non adjacent beams of a satellite.2Sharing of Forward CDMA Channel: It is also possible for two gateways to share a single3subbeam. This mode is used when a gateway’s traffic needs only a fraction of a subbeam and each4gateway must supply a separate pilot. In particular, this mode is useful when a satellite beam is moving5from gateway service area A to gateway service area B. Gateways A and B can then share a subbeam6as the traffic from A is ramping down and the traffic from B is ramping up. When sharing the first7gateway will use all even-numbered code channels, and the second gateway will use all odd-numbered8code channels.9The Pilot Channel of the first gateway is transmitted on code channel 0. The Sync Channel associated10with this Pilot Channel, if it exists, is transmitted on code channel 32. The Primary Paging Channel11(Paging Channel number 1) of the first gateway, if it exists, is transmitted on code channel 64. Paging12Channel numbers 2, 3, 4, 5, 6, and 7, if they exist, are transmitted on code channels 2, 66, 4, 68, 6, and1370, respectively.14The Pilot Channel of the second gateway is transmitted on code channel 1. The Sync Channel15associated with this Pilot Channel, if it exists, is transmitted on code channel 33. The Primary Paging16Channel (Paging Channel number 1) of the second gateway, if it exists, is transmitted on code channel1765. Paging Channel numbers 2, 3, 4, 5, 6, and 7, if they exist, are transmitted on code channels 3, 67,185, 69, 7, and 71, respectively.194.6 Return Link CDMA Channel20The Reverse CDMA Channel is composed of Access Channels and Reverse Traffic Channels as shown21in Figure 4-8.22Access ChTraffic Ch 1Traffic Ch mREVERSE CDMA CHANNEL (1.23 MHz channel received by gateway)••••••••••••••••••••••••••••••••23Figure 4-8. Reverse CDMA Channels Received at a Gateway24
Description of a Globalstar Gateway GS-TR-94-0001Revision E4-11Figure 4-8 shows an example of all of the signals received by a gateway on the Reverse CDMA1Channel. These channels share the same CDMA frequency assignment using direct-sequence CDMA.2Each Traffic Channel is identified by a distinct user long code sequence. Each Access Channel is3identified by its quadrature spreading codes and the gateway identification in the long code mask.4Multiple Reverse CDMA Channels on different frequencies may be used by a gateway.5The Reverse CDMA Channel has the overall structure shown in Figure 4-9 and Figure 4-10. Data6transmitted on the Reverse CDMA Channel is grouped into 20 ms frames. All data transmitted on the7Reverse CDMA Channel is convolutionally encoded, block interleaved, modulated by the 64-ary8orthogonal modulation, and direct-sequence spread prior to transmission.9Access Channel: The Access Channel is used by the User Terminal for communicating to the10Gateway. It is used for short signaling message exchanges such as call origination, response to pages,11and registrations. The Access channel is a slotted random access channel. Each Access Channel, as12shown in Figure 4-9, is identified by a distinct Access Channel long code sequence.139.6 kspsAccess Channel Information Bits (88 bits/frame)Code Symbol64-ary Orthogonal Modulator1.6 ksps (102.4 kcps)Modulation Symbol (Walsh chip)Add 8 bit Encoder Tail 4.8 kbps4.4 kbps1/2 PN chip Delay = 406.9 nsDQ(t)I(t)Baseband FilterBaseband FilterI-channel Sequence 1.2288 McpsQ-channel Sequence 1.2288 McpsIQ1.2288 McpsLong Code GeneratorPN chipLong Code Masks(t)sin(2πfct)cos(2πfct)ΣΣConvolutional Encoder r=1/2 K=9Code Symbol9.6 kspsBlock Interleaver14Figure 4-9 Return Link Access Channel15
Description of the Globalstar System GS-TR-94-0001Revision E4-12Return Link Traffic Channel: Each Traffic Channel is identified by a distinct user long code1sequence as shown in Figure 4-10.29.6 kbps 4.8 kbps 2.4 kbps 0 kbps Convolutional Encoder r=1/2 K=9Reverse Traffic Channel Information Bits (171, 79, 32, or 0 bits/frame)Code SymbolAdd 8 bit Encoder TailAdd Frame Quality Indicators for 9.6, 4.8 & 2.4 kbps 8.55 kbps 3.95 kbps 1.6 kbps 0 kbps 1/2 PN chip Delay = 406.9 nsDQ(t)I(t)Baseband FilterBaseband FilterI-channel Sequence 1.2288 McpsQ-channel Sequence 1.2288 McpsIQ1.2288 McpsLong Code GeneratorPN chipLong Code Masks(t)sin(2πfct)cos(2πfct)ΣΣ19.2 ksps 9.6 ksps 4.8 ksps 0 ksps64-ary Orthogonal ModulatorModulation Symbol (Walsh chip)3.2 ksps (204.8 kcps) 1.6 ksps (102.4 kcps) 0.8 ksps (51.2 kcps) 0.2 ksps (12.8 kcps)Block InterleaverCode SymbolAdd Power Control Bit for 9.6, 4.8 & 2.4 kbps Power Control Bit for 0 kbps Frame 8.6 kbps 4.0 kbps 1.65 kbps 0 kbps 9.2 kbps 4.4 kbps 2.0 kbps 0 kbps 3Figure 4-10 Return Link Traffic Channel4The rate 1/2 code used for the Globalstar return link takes advantage of longer coherence times for the5channel and will perform better in the Additive White Gaussian Noise (AWGN) channel typical of6Globalstar. The rate 1/3 code, typically used in terrestrial CDMA, performs better in a Rayleigh7channel because it offers greater diversity. The return link does not use the randomizer used in cellular8CDMA. It uses a continuous transmission with code symbol repetition to maintain the same rate.94.7 CDMA End to End Performance10There are a number of other CDMA topics that span both the forward and return links.11Time: All gateway digital transmissions are referenced to a common CDMA system-wide time scale12that uses the Global Positioning System (GPS) time scale, which is traceable to and synchronous with13Universal Coordinated Time (UTC). GPS and UTC differ by an integer number of seconds, specifically14the number of leap second corrections added to UTC since January 6, 1980. The start of CDMA15System Time is January 6, 1980 00:00:00 UTC, which coincides with the start of GPS time. System16Time keeps track of leap second corrections to UTC but does not use these corrections for physical17adjustments to the System Time clocks. When receiving the paging channel, the User Terminal is within181.0 microseconds of the earliest arriving signal used for demodulation.19
Description of a Globalstar Gateway GS-TR-94-0001Revision E4-13Link Delay: Delay through a link is an important end to end parameter. It becomes particularly1important in conversations when one party attempts to interrupt the other. The LEO orbit satellites will2provide a much more benign delay than the more common synchronous orbit satellites. Delay is held to3150 ms in each direction. There is a design margin, of course. Figure 4-11 summarizes the delay for the4forward link.5SBSSample & Vocoder EncodeMSSL Queue & TransmitDistribute MSSL Queue & TransmitHDLC Consolidate ATMModulator CardUser TerminalCISGTS69 ms0.5 ms1 ms5 ms3.25 ms43.4 ms18 ms6Figure 4-11 Forward Link Delay Budget7Figure 4-12 illustrates the delay budget for the return link.8SBSSelect & Vocoder DecodeMSSL Queue & TransmitDistribute MSSL Queue & TransmitHDLC Consolidate ATMDemodulator CardUser TerminalCISGTS 3.5 ms0.5 ms1 ms3.5 ms15 ms43.4 ms69.5 ms9Figure 4-12 Reverse Link Delay Budget10Tradeoffs are possible to improve voice quality, improve capacity or other system level parameters at11the expense of end to end delay.12
Description of the Globalstar System GS-TR-94-0001Revision E4-14Vocoder: The Globalstar vocoder is uses a Code Excited Linear Prediction (CELP) algorithm with a1structure similar to that used by the IS-96 coder but with several improvements. The percentage of time2between rates of 0 b/s and 8,550 can be adjusted. Voice quality can be traded for capacity. Voice3quality can also be traded for signal delay. The Globalstar design will operate with high voice quality4when the capacity is not stressed and when the links can be closed. If the links cannot be closed or if5the capacity is being stressed, voice quality can be sacrificed. Vocoder rates and resulting channel rates6are shown in Table 4-1.7Table 4-1 Vocoder and Channel Rates8Configuration Vocoder Rate Channel Rate PurposesRate 1 8,550 9,600 High Quality OptionRate 1/2 3,950 4,800 Baseline VoicedRate 1/4 1,750 2,400 Baseline UnvoicedRate 1/8 800 1,200 Baseline Pauses/Background9Some improvements are envisioned that may increase capacity. In the forward direction, a zero rate10can be used. Since this is the coherent direction, the User Terminals can stay locked on by using the11pilot. This is the direction that constrains capacity. In the return direction, some energy must be12transmitted to keep the receiver locked since the return direction is not coherent.13Power Control: The objective of power control is to transmit the minimum power necessary in order14to achieve a given quality of service. Quality of service could be specified in terms of the Frame Error15Rate (FER) and the probability of outage. Accurate power control reduces the transmit power needed16to achieve a given quality of service objective, thereby prolonging battery life of portable phones. In17addition, it also enhances capacity. Figure 4-13 is a simplified end to end diagram to support the18description of power control.19Channel GatewayPhonetxtxrxrxReverse LinkForward LinkCorrelationSegment Transmit PathBTransmit Gain Setting: Power Control AlgorithmABBAA20Figure 4-13 Power Control Simplified Diagram21Power Control and time to acquire are intimately related as shown in Figure 4-14.22
Description of a Globalstar Gateway GS-TR-94-0001Revision E4-150102030405060708090-20 -18 -16 -14 -12 -10Ec/Io (dB)95% TimeMean Time1Figure 4-14 Acquisition Time as a function of Eb/No2Once the target for Eb/No is established, the task of power control is to maintain the desired Eb/No.3Acquisition time will extend if the Eb/No is not well established correctly or controlled to the desired4value. In order to achieve the power control there are two loops.5Inner Loop: The inner loop controls to the target Eb/No on a one bit per frame basis.6Outer Loop: The outer loop adjusts the target Eb/No based on the measured Frame Error Rate.7
Description of the Globalstar System GS-TR-94-0001Revision E4-16This page intentionally left blank.12
Description of the Globalstar System GS-TR-94-0001Revision E5-15. TERRESTRIAL INTERFACE15.1 Telecommunication Network Interface2The Gateway Architecture emphasizing the terrestrial interface is shown in Figure 5-1.3GSM HLRGSM HLRCDMA Subsystem (GTS/TFU/CIS/ SBS/GC)IS-41 CCP/VLR SSAGSM HLRIS-41 HLRGOCC SPCCsOMC/SPCCGSM MSC/VLRGSM MSC/VLRQ InterfaceA1 Interface(s)GSM MAPIS-41 MAPT1/E1 - ISUP/MF-R2T1/E1 - ISUP/MF-R2GMSGatewayGSM MSC/VLRBSCIBSSPSTN4Figure 5-1 Gateway Architecture5The Gateway can operate in territories with terrestrial systems which are predominately GSM based or6IS-41 C based.7GSM: In a GSM environment, the GSM-MSC can either be incorporated in the Gateway or it can be8external. If external, it can be directly associated with the Gateway or shared with other terrestrial9cellular systems. A protocol conversion process may be required to support IS-41 roamers whose10home networks use ANSI SS-7 for MAP signaling rather than ITU SS-7. Protocol conversion may be11performed by the international SS-7 carrier or by a separate device. GSM roamers whose home12networks comply with ITU SS-7 do not require protocol conversion support.13IS-41: In an IS-41 network, a GSM-MSC must be available to provide GSM roaming services. The14switch can either be in the gateway or can be back hauled to a GSM-MSC in another location.15
Description of the Globalstar System GS-TR-94-0001Revision E5-2Protocol conversion may be required to convert between ITU SS-7 and ANSI SS-7 for mobility1signaling to support international roamers with different home signaling protocols.2Flexible Interface: In areas where there is no infrastructure or where there is an infrastructure other3than GSM or IS-41, the Gateway can interface directly to the PSTN. The Gateway has a built in4switch than can be adapted to a variety of PSTNs. This, of course, does not address type qualification5which may or may not be a large problem depending on the specific country and situation involved.6The entities associated with the terrestrial network of primary interest include:7GSM MSC/VLR: The GSM Mobile Switching Center (MSC) and Visitor Location Register (VLR)8provide the call control and mobility management functions for GSM based users in the GW coverage9area. The GSM MSC terminates one end of the A1 Interface, processing the BSSMAP and DTAP10messages carried on this interface. The GSM VLR maintains the subscriber records for GSM based11UTs operating on the GW. In addition, the GSM VLR interfaces to the existing GSM terrestrial cellular12mobile Home Location Register (HLR) network. The GSM MSC also provides an interface to the13local PSTN via standard signaling protocols (ISUP, MF-R1, MF-R2, etc.).14GSM HLR/AuC: The GSM HLRs that are accessible from the GW are new or existing terrestrial15cellular HLRs in the GSM MAP network. These HLRs contain the home subscriber records for GSM16based GW UT subscribers.17IS-41 CCP/VLR/SSA: For IS-41 based users in the GW, the IS-41 based call control and mobility18management functions are processed by the IS-41 CCP/VLR/SSA entity. The IS-41 VLR maintains19the subscriber records for IS-41 based UTs operating on the GW. In addition, the VLR interfaces to20the existing IS-41 terrestrial cellular mobile Home Location Register (HLR) network. The SSA21interfaces the GW to the local PSTN via standard signaling protocols (ISUP, MF-R1, MF-R2, etc.).22The GW can also be configured in such a manner where the SSA can directly interface to one or more23of the GW GSM MSCs if desired.24IS-41 HLR/AuC: The IS-41 HLRs that are accessible from the GW are existing terrestrial cellular25HLRs in the IS-41 MAP network. These HLRs contain the home subscriber records for IS-41 based26GW UT subscribers. The IS 41 C Authentication Center provides authentication for its IS-41 C based27Globlastar Subscribers.28
Description of the Globalstar System GS-TR-94-0001Revision E5-3Figure 5-2 provides more details on what is inside the Globalstar Gateway.12Figure 5-2 Gateway Connections to the PSTN - Flexible Interface3Physical Interface: The Gateway will connect to telecommunications networks via standard T1/E1.4This is accomplished by the Service Switching Adjunct (SSA) shown in the upper right of Figure 5.1-2.5This is also called Service Switching Point (SSP) in intelligent networks.6PSTN Interface Protocols: The Gateway provides an Integrated Service Digital Network (ISDN)7interface and will connect to the PSTN via Primary Rate Interface (PRI).8SPCC GW Links E1 or T1BCN MSSLEthernetIFLPSTNSSAPatch PanelCSUNISGWRDBVLRPatch PanelPatch PanelBSCI GSMMSCVLRT1/E1TrunksSBSCIS(DISCO)GTSRLTFUGPS RcvrRouterSPCC RouterGDNFL7 561211108 4219 3Up ConverterSSPARLLNADownConverterAntennas(up to 4)TCU PanelTCUTCUTCUTCUGSS(Gateway Switching System)GCS(Gateway CDMA System)GMS(Gateway Management System)GOCCSOCCTCU(Telemetry & Command Unit)ROPIGRS(Gateway RF System)DigitalCabinets(up to 13)DemodCardsFL CabinetRHCPLHCPRHCPLHCPGSMHLRIS-41HLRE1TrunksSS7SS7SS7VMEBackplaneCommonCardReceiveCabinets(up to 13)ReceiverCardsControllerCardSBS Shelf1/96 callsSelectorCards (12)InterfaceCardΣΣGCUT1FL Shelf(40)5/polarize/antUpconverterCardsModulatorCardsGDN Router147*2580369#DGlobalstarDIGITAL BYABCTFUCabinet(2)SplittersTFUCabinet(2)Splitters147*2580369#ON OFFDGlobalstarDIGITAL BYVME CageCCPVME CageGWCVME CageSS7ServerCDAVIP213Trunk Set Combinations(most likely):· IS-41 territory:· GSM territory:T11 22 3OMCGMOPI
Description of the Globalstar System GS-TR-94-0001Revision E5-45.2 Registration Process1Registration is the process by which the User Terminal notifies the Gateway of its location, status,2identification, User Terminal type, and paging slot being monitored. Under normal circumstances, the3Globalstar Gateway only contains a Visitor Location Register which is used in conjunction with external4GSM or IS-41 Home Location Registers. Registration with an external HLR will be supported through5the Gateway VLR. Registration while roaming involves the exchange of information between system6types (GSM to IS-41 or visa versa). The messages and procedures for exchange of authentication data7with the AuC/HLR is currently being reviewed by TIA for inclusion in IS-41D, and is summarized in8TSB-51, Cellular Radio Telecommunications Inter systems Operation: Authentication, Signaling9Message Encryption and Voice Privacy.10There are two registration processes that will be supported.11User Terminal User ID HLR VLRIS-95 Modified ESN/MIN IS-41 GlobalstarIS-95 Modified GSM/IMSI GSM GlobalstarIS-41 HLR Registration: Figure 5-3 illustrates the process of registration of an IS-95 User Terminal12within an IS-41 HLR.13Home system SPC is determined from ESN/MINVisitorLocationRegister(VLR)SS7A record is created in the Visitor Location Register (VLR) and stored with profile information. User is deregistered on shutdown or REGCANC from HLRData Message includes ESN/MIN or IMEI1.2.6.The visited Gateway sends a data message that includes the phone ESN/MIN to the HLR across the signaling network. 3.IS-41 MAPmessages(Visiting)TerminalUserHomeLocationRegister(HLR)Home Location RegisterSS7The Customer Profile is scanned for an ID match and the present GW address is updated in the HLR.The subscriber profile is returned to the Gateway. User is deregistered from previous VLR (REGCANC)4.5.GatewayCDMAGateway (Visited)Notes:ESN = Electronic Serial NumberMIN = Mobile Identification NumberSPC = Switching Point CodeGAIGlobalstar Air InterfaceAuthenticationCenter (Future)SS7SignalingNetworkANSIIMEI = International MobileEquipment IdentifierIS 41 Authenticates EquipmentANSIANSIIS-41 MapDataIS-41 MapDataFile: Reg IS-41 Rev: 10/14/9514Figure 5-3 Registration of a U.S. based User with an IS-41 HLR15
Description of the Globalstar System GS-TR-94-0001Revision E5-5If IMEI are used in the User Terminals, ESN will not be stored. ESN is computed from the IMEI. The1IMEI also incorporates the type approval code.2GSM HLR Registration: Here, all of the network components (MSC, HLR, VLR and AuC) should3be able to communicate as in the normal system. The challenge is reduced to a protocol inter working4task on the Gateway-VLR and Gateway-MSC interfaces, and transport of GSM authentication data to5and from the SIM. Figure 5-4 illustrates the registration process.6Home system SPC is determined from the User IDC 7Data Messaage includes User ID1.2.The visited Gateway sends a data message that includes the User ID to the HLR across the signaling network.3.GSM MAPmessagesC 7SignalingNetworkVisitingTerminalGSM UserHomeLocationRegister(HLR)Home Location RegisterC 7The Customer Profile is scanned for a User ID match and the present location is updated in the Home Location Register (HLR).4.GatewayCDMAGateway (Visited)Notes:SPC = Switching Point CodeID = IdentificationMAP = Mobile Application ProtocolA record is created in the Visitor Location Register (VLR) and stored with profile information. User is deregistered on shutdown6. The subscriber profile is returned to the Gateway. User is deregistered from previous VLR.5.AuthenticationCenterKc TripletSIM CardGAIGlobalstarAirInterface ITUGSM Authenticates SubscriberGSM - MAPDataGSM-AVisitorLocationRegister(VLR)MSCMobileSwitching CenterITU ITU GSM - MAPDataFile: Reg GSM Rev: 10/14/957Figure 5-4 Registration of a European User in a GSM HLR8
Description of the Globalstar System GS-TR-94-0001Revision E5-6Home system SPC is determinedC 7A record is created in the Visitor Location Register (VLR) and stored with profile information. User is deregistered on shutdown or upon command from the HLR.2.6.The visited Gateway sends a data message that includes the phone ID to the HLR across the signaling network.3.Home Location RegisterSS7The Customer Profile is scanned for an ID match and the present GW address is updated in the HLR.The subscriber profile is returned to the Gateway. User is deregistered from previous VLR.4.5.IS-41 MAPGatewayCDMAGateway (Visited)Notes:ESN = Electronic Serial NumberMIN = Mobile Identification NumberSPC = Switching Point CodeID = Identification (MIN & ESN)HomeLocationRegister(HLR)AuthenticationCenter (Future)Data Message includes ESN/MIN1.VisitingTerminalUserGAIGlobalstarAirInterfaceor IMEIIS-41 CallControl ProcessorVLRIS-41 MAPITU SS-7ITU ANSIProtocol ConverterITU-ANSISS-7DataFile: Reg IS-41 GSM Rev: 10/14/951Figure 5-5 Registration of a U.S. User in a GSM Environment2
Description of the Globalstar System GS-TR-94-0001Revision E5-7Home system SPC is determinedSS72.The visited Gateway sends a data message that includes the User ID to the HLR across the signaling network.3.HomeLocationRegister(HLR)Home LocationC 7The Customer Profile is scanned for an ID match and the present GW address is updated in the HLR.4.Gateway (Visited)Notes:SPC = Switching Point CodeID = IdentificationMAP = Mobile Application ProtocolA record is created in the Visitor Location Register (VLR) and stored with profile information. User is deregistered on shutdown or upon command from the HLR6.The subscriber profile is returned to the Gateway. User is deregistered from previous VLR.5.GatewayAuthenticationCenterData Messaage includes User ID1.VisitingTerminalGSM UserSIM CardGAIGlobalstarAirInterfaceANSIITUCDMAGSM-AVisitorLocationRegister(VLR)MSCMobileSwitching CenterGSM - MAPDataGSM - MAPDataANSI-ITUProtocolConverterSS-7Kc TripletGSM Authenticates SubscriberReg GSM IS-41 Rev: 10/14/9 51Figure 5-6 Registration of a European User in an IS-41 Environment25.3 Authentication Process3Authentication verifies that the User Terminal is authorized to use the Globalstar resources. The4Gateway will support authentication of the User Terminals; but, authentication is the responsibility of the5home PLMN operator. The Gateway will transport authentication messages in the form required by the6home PLMN operator. The Gateway will incorporate facilities to challenge, examine and update the7authentication signature in the User Terminals.8To achieve a consistent authentication scheme, the system adopted must be able to deal with each of the9following situations:10a. GSM User in GSM System11b. IS-41 User in IS-41 System12c. GSM User in IS-41 System13d. IS-41 User in GSM System14Where IS-41 User indicates a user whose Home system is based upon the IS-41 model and protocols15(i.e. AMPS, IS-54, IS-95 and PSTN systems), and a GSM or IS-41 System indicates a serving16
Description of the Globalstar System GS-TR-94-0001Revision E5-8Globalstar system where the mobility management facilities (HLR, VLR etc.) are GSM or IS-41-based,1respectively.2GSM User in GSM System: Here, all of the network components (MSC, HLR, VLR and AuC)3should be able to communicate as in the standard GSM system. The challenge is reduced to a protocol4inter working task on the Gateway-VLR and Gateway-MSC interfaces, and transport of GSM5authentication data to and from the SIM. GSM roamers do not require a protocol converter. GSM6uses the same SS-7 as the international signaling.7IS-95 user in IS-95 (IS-41) System: All of the network components and protocols will operate in an8IS-41 system. IS-41D supports and authentication center. Some networks may not support9authentication.10GSM User in IS-95 (IS-41) System: In this scenario, the various network components belong to11different systems, as summarized in the following table:12Component SystemSIM GSMGateway/MSC IS-41VLR IS-41HLR/AuC GSM13The task that needs to be solved in this scenario is the retrieval and storage of authentication data from14the HLR/AuC. For example, the triplets could be both requested and stored by the Gateway and the15RAND and SRES parameters carried on the air interface to/from the SIM.16The general message exchange is illustrated in Figure 5-7:17
Description of the Globalstar System GS-TR-94-0001Revision E5-9Subscriber UnitHLR/AuCGatewayInsert Subscriber DataSend ParametersSend Parameters ResponseAuthentication ChallengeAuthentication Challenge ResponseAuthentication ChallengeAuthentication Challenge ResponseSIMRANDSRESRANDSRESFile: GSM in IS411Figure 5-7 Authentication for a GSM User in IS-41 System2IS-95 User in GSM System: In this scenario, the various network components belong to different3systems, as summarized in the following table:4Component SystemUser Terminal IS-95/GlobalstarGateway/MSC GSMVLR GSMHLR/AuC IS-415In the IS-41 system, authentication is done mainly by the Gateway, with updates to authentication6parameters periodically being retrieved from the AuC. The Gateway just has to recognize that the user7understands IS-41 authentication, and not GSM and process messages appropriately.8The messages and procedures for exchange of authentication data with the AuC/HLR is currently being9reviewed by TIA for inclusion in IS-41C, and is summarized in TSB-51, Cellular Radio10Telecommunications Inter systems Operation: Authentication, Signaling Message Encryption and Voice11Privacy.12
Description of the Globalstar System GS-TR-94-0001Revision E5-105.4 GSM - A Interface in Globalstar1The Globalstar Gateway will interface with and MSC in the GSM environment in much the same way2that any base station interfaces with the MSC. Figure 5-8 illustrates a typical GSM DTAP on Mobile3Terminated Calls.4UT GW (BSS) GSM MSCSignalling Channel RequestCR (PAGE RESP)DT1 (CPH MOD CMD)DT1 (SETUP)DT1 (CALL CONFIRM)DT1 (ASS REQ)DT1 (ASS COM)Request for ServiceActivates Encryption, Service Option at SelectorActivates Traffic Voice PathDT1 (CPH MOD COM)DT1 (ALERT)DT1 (CONNECT)DT1(CONNECT ACK)CDMA Radio Processing EventsUDTStable 2-way Call5Figure 5-8 GSM DTAP on Mobile Terminated Call6Figure 5-9 Illustrates GSM DTAP on a typical mobile originated call in Globalstar.7
Description of the Globalstar System GS-TR-94-0001Revision E5-11UTGW (BSS)GSM MSCSignalling Channel RequestCR (CM SERV REQ)CC (AUTH REQ)DT1 (CPH MOD CMD)DT1 (AUTH RESP)DT1 (SETUP)DT1 (CALL PROCEED)DT1 (ASS REQ)DT1 (ASS COM)Request for Service & AuthenticationActivates Encryption, Service Option at SelectorActivates Traffic Voice PathDT1 (CPH MOD COM)DT1 (ALERT)DT1 (CONNECT)DT1(CONNECT ACK)Stable 2-way CallCDMA Radio Processing Events1Figure 5-9 GSM DTAP on Mobile Originated Call23
Description of the Globalstar System GS-TR-94-0001Revision E5-12This page intentionally left blank.12
Description of the Globalstar System GS-TR-94-0001Revision E6-16. CALL PROCESSING16.1 Call Processing between Globalstar and PLMN2This section discusses call processing between Globalstar and other PLMN systems. In Globalstar all3User Terminals are treated as roaming from their terrestrial PLMN home system.4Globalstar Only User Terminals: There are a series of User Terminals that are Globalstar Only. In5these cases the service provider will incorporate the Globalstar Only User Terminals in the local Home6Location Register (HLR). This applies to GSM or IS-41 HLRs. The Gateway will treat Globalstar7Only UTs as Roamers.8No Existing HLRs: In areas where there is no existing HLR, Globalstar may set up an HLR and9function as the Service Provider.10Emergency Calls: Globalstar will comply with the regulations for delivery of emergency calls.11Mobile Originated Call: Figure 6-1 illustrates how a mobile originated call is processed.12File: UT OriginSwitch or MSCCDMA VLRCall EstablishmentORIGREQorigreq1234GatewayOrigination Request From User13Figure 6-1 Mobile Originated Call14The following steps are performed:151. An Origination Request (ORIGREQ) is received from a User Terminal.162. An Origination Request INVOKE is sent from the Gateway (GW) to the VLR.17
Description of the Globalstar System GS-TR-94-0001Revision E6-23. The Mobile is currently registered in this Visitor Location Register (VLR). The VLR1responds with the Origination Request RETURN RESULT parameters.24. The call is established with the terrestrial system.3Mobile Terminated: There are two scenarios for roaming call delivery. The first one is for a4successful call (i.e. the user is idle). In the second case, the user is busy - this case is used to illustrate5the possible invocation of a supplementary service such as Call Forward on Subscriber Busy.6Roaming Call Delivery - Idle Case: Figure 6-2 illustrates a successful call connection.7Originating SystemSwitch or MSCGWVLR HLRGWVLRServing Systemcall origination LOCREQROUTREQroutreqroutreq [TLDN]locreq [TLDN]12345678Call SetupROUTREQ8Figure 6-2 Roaming Call Delivery - Successful910The following steps are performed:111. The switch attempts to deliver a call to the home Gateway of a mobile. In this scenario, the12mobile is roaming, and so is not registered at the VLR of the home system.132. The VLR sends a Locate Request (LOCREQ) INVOKE to the Home Location Register14(HLR) requesting the location of the mobile.15
Description of the Globalstar System GS-TR-96-0021Revision E6-33. The HLR determines the serving system for the User Terminal and sends a Routing Request1INVOKE to the serving VLR.24. The VLR sends a Routing Request (ROUTREQ) INVOKE to the Gateway to request the3allocation of a Temporary Local Directory Number (TLDN) for the mobile.45. The Gateway allocates a TLDN and returns the result in a Routing Request RETURN5RESULT.66. The VLR returns this TLDN to the HLR in the Routing Request RETURN RESULT.77. The HLR sends the TLDN to the originating VLR via Locate Request RETURN RESULT.88. The Gateway forwards the call to the destination Gateway (using the TLDN) and call setup is9initiated with the serving Gateway.10Roaming Call Delivery - Busy Case: This scenario illustrates the case where the called number is11busy in a roaming system. The message exchange would be similar if features such as call forwarding12were activated. Figure 6-3 is a case where the called number is busy.13Originating SystemSwitch or MSCGWVLR HLRGWVLRServing Systemcall origination LOCREQROUTREQROUTREQroutreqroutreq [busy]locreq [busy]1234567busy 814Figure 6-3 Roaming Call Delivery - Subscriber Busy15
Description of the Globalstar System GS-TR-94-0001Revision E6-4The following steps are performed:11. The switch attempts to deliver a call to the home Gateway of a mobile. In this scenario, the2mobile is roaming, and so is not registered at the VLR of the home system.32. The VLR sends a Locate Request (LOCREQ) INVOKE to the HLR requesting the4location of the mobile.53. The HLR determines the serving system for the User Terminal and sends a Routing Request6INVOKE to the serving VLR.74. The VLR sends a Routing Request INVOKE to the Gateway to request the allocation of a8Temporary Local Directory Number (TLDN) for the mobile.96. The Gateway determines that the mobile is busy in another call and returns the result in a10Routing Request RETURN RESULT.116. The VLR returns this notification to the HLR in the Routing Request RETURN RESULT.127. The HLR sends the result to the originating VLR via Locate Request RETURN RESULT,13and the VLR forwards the result to the Gateway.148. The Gateway returns a busy indication to the network.15Note that in the case of other call setup failures e.g. if Call Forwarding has been activated, the same16scenario applies in principle, but the indication contained within the messages are different.17
Description of the Globalstar System GS-TR-96-0021Revision E6-56.2 TIA and ETSI Call Flow Examples1This is an informative appendix which contains examples of call flows. The diagrams follow these2conventions:3• All messages are received without error4• Receipt of messages is not shown except in the handoff examples5• Acknowledgments are not shown6• Authentication procedures are not shown7• Encryption mode transitions are not shown8
Description of the Globalstar System GS-TR-94-0001Revision E6-61User Terminal Gateway•Detects user-initiated call•Sends Origination Message >Access Channel >•Sets up Traffic Channel•Begins sending null TrafficChannel data•Sets up Traffic Channel <Paging Channel <•Sends Channel AssignmentMessage•Receives N5m consecutive validframes•Begins sending the Traffic Channelpreamble•Acquires the Reverse TrafficChannel•Begins transmitting null TrafficChannel data<Forward TrafficChannel<•Sends Gateway AcknowledgmentOrder•Sends Service Request Message forService Option 1>Reverse TrafficChannel>•Allocates resources for ServiceOption 1•Begins processing primary traffic inaccordance with Service Option 1<Forward TrafficChannel<•Sends Service Connect Message•Sends Service Connect CompletionMessage>Reverse TrafficChannel>Optional Optional•Sends Origination ContinuationMessage>Reverse TrafficChannel>Optional Optional•Applies ring back in audio path <Forward TrafficChannel<•Sends Alert With InformationMessage (ring back tone)Optional Optional•Removes ring back fromaudio path<Forward TrafficChannel<•Sends Alert With InformationMessage (tones off)(User conversation) (User conversation)2Figure 6-4 Simple Call Flow, User Terminal Origination Example Using Service Option 13(TIA Call Control Procedures)4(Part 1 of 2)56
Description of the Globalstar System GS-TR-96-0021Revision E6-7User Terminal Gateway•Detects user-initiated call•Sends Channel Request Messageindicating call origination andservice option requested>Access Channel >•Sets up Traffic Channel•Begins sending null TrafficChannel data•Sets up Traffic Channel <Paging Channel <•Sends Channel AssignmentMessage•Receives N5m consecutive validframes•Begins sending the Traffic Channelpreamble•Acquires the Reverse TrafficChannel•Begins transmitting null TrafficChannel data<Forward TrafficChannel<•Sends Gateway AcknowledgmentOrder•Sends ETSI Layer 3 TransportMessage containing CC Setupmessage>Reverse TrafficChannel>• Starts setting up a call• See the note below <Forward TrafficChannel<•Sends ETSI Layer 3 TransportMessage containing CC Call-Proceeding messageNote: The gateway and the user terminal follow the call establishment procedures as defined in section 5.2.1 ofETS 300 557, GSM 04.08.•Begins processing primary traffic inaccordance with Service Option 1<Forward TrafficChannel<•Sends Service Connect Message•Sends Service Connect CompletionMessage>Reverse TrafficChannel>(User conversation) (User conversation)1Figure 6-5 Simple Call Flow, User Terminal Origination Example Using Service Option 12(ETSI Call Control Procedures)3(Part 2 of 2)4
Description of the Globalstar System GS-TR-94-0001Revision E6-81User Terminal Gateway<Paging Channel <•Sends General Page Message•Sends Page Response Message >Access Channel >•Sets up Traffic Channel•Begins sending null TrafficChannel data•Sets up Traffic Channel <Paging Channel <•Sends Channel AssignmentMessage•Receives N5m consecutive validframes•Begins sending the Traffic Channelpreamble•Acquires the Reverse TrafficChannel•Begins transmitting null TrafficChannel data<Forward TrafficChannel<•Sends Gateway AcknowledgmentOrder•Allocates resources for ServiceOption 1<Forward TrafficChannel<•Sends Service Request Message forService Option 1•Sends Service Response Messageaccepting Service Option 1>Reverse TrafficChannel>•Begins processing primary traffic inaccordance with Service Option 1<Forward TrafficChannel<•Sends Service Connect Message•Sends Service Connect CompletionMessage>Reverse TrafficChannel>•Starts ringing <Forward TrafficChannel<•Sends Alert With InformationMessage (ring)•User answers call•Stops ringing•Sends Connect Order >Reverse TrafficChannel>•Begins sending primary trafficpackets from the Service Option 1application(User conversation) (User conversation)2Figure 6-6. Simple Call Flow, User Terminal Termination Example Using Service Option31 (TIA Call Control Procedures)4(Part 1 of 2)5
Description of the Globalstar System GS-TR-96-0021Revision E6-91User Terminal Gateway<Paging Channel <•Sends General Page Message withservice option requested•Sends Channel Request Messageindicating paging response>Access Channel >•Sets up Traffic Channel•Begins sending null TrafficChannel data•Sets up Traffic Channel <Paging Channel <•Sends Channel AssignmentMessage•Receives N5m consecutive validframes•Begins sending the Traffic Channelpreamble•Acquires the Reverse TrafficChannel•Begins transmitting null TrafficChannel data<Forward TrafficChannel<•Sends Gateway AcknowledgmentOrder•Sends ETSI Layer 3 TransportMessage containing RR PagingResponse message>Reverse TrafficChannel>•Starts alerting <Forward TrafficChannel<•Sends ETSI Layer 3 TransportMessage containing CC Setupmessage•Sends ETSI Layer 3 TransportMessage containing CCCall_Confirmed message>Reverse TrafficChannel>• See note belowNote: The gateway and the user terminal follow the call establishment procedures as defined in section 5.2.2 ofETS 300 557, GSM 04.08.•Begins processing primary traffic inaccordance with Service Option 1<Forward TrafficChannel<•Sends Service Connect Message•Sends Service Connect CompletionMessage>Reverse TrafficChannel>(User conversation) (User conversation)Figure 6-7 Simple Call Flow, User Terminal Termination Example Using Service Option 12(ETSI Call Control Procedures)3(Part 2 of 2)4
Description of the Globalstar System GS-TR-94-0001Revision E6-101User Terminal Gateway•Detects user-initiated disconnect•Sends Release Order >Reverse TrafficChannel><Forward TrafficChannel<•Sends Release Order•Enters the System DeterminationSubstate of the User TerminalInitialization State2Figure 6-8. Simple Call Flow, User Terminal Initiated Call Disconnect Example (TIA Call3Control Procedures)4(Part 1 of 2)56User Terminal Gateway•Detects user-initiated disconnect•Sends ETSI Layer 3 TransportMessage containing CC Disconnectmessage>Reverse TrafficChannel>• Initiates procedures to clear thenetwork connection• Releases the MM connection <Forward TrafficChannel<• Sends ETSI Layer 3 TransportMessage containing CC Releasemessage• Sends ETSI Layer 3 TransportMessage containing CC ReleaseComplete message1>Reverse TrafficChannel>• Releases the MM connection• Releases the RR connection (TrafficChannel)<Forward TrafficChannel<•Sends Release Order•Enters the System DeterminationSubstate of the User TerminalInitialization StateFigure 6-9 Simple Call Flow, User Terminal Initiated Call Disconnect Example (ETSI Call7Control Procedure)8(Part 2 of 2)9 1For more details see call release procedures defined in section 5.4.3 of ETS 300 557, GSM 04.08.
Description of the Globalstar System GS-TR-96-0021Revision E6-111234User Terminal Gateway•Detects call disconnect<Forward TrafficChannel<•Sends Release Order•Sends Release Order >Reverse TrafficChannel>•Enters the System DeterminationSubstate of the User TerminalInitialization State5Figure 6-10. Simple Call Flow, Gateway Initiated Call Disconnect Example (TIA Call6Control Procedures)7(Part 1 of 2)8
Description of the Globalstar System GS-TR-94-0001Revision E6-121User Terminal Gateway•Detects call disconnect<Forward TrafficChannel<• Sends ETSI Layer 3 TransportMessage containing CCDisconnect message• Sends ETSI Layer 3 TransportMessage containing CC Releasemessage>Reverse TrafficChannel>• Releases the MM connection• Releases the MM connection <Forward TrafficChannel<• Sends ETSI Layer 3 TransportMessage containing CC Release2Complete message• Releases the RR connection (TrafficChannel)<Forward TrafficChannel<•Sends Release Order•Enters the System DeterminationSubstate of the User TerminalInitialization State2Figure 6-11 Simple Call Flow, Gateway Initiated Call Disconnect Example (ETSI Call3Control Procedure)4(Part 2 of 2)56 2 For more details see the call release procedures as defined in section 5.4.4 of ETS 300 557, GSM 04.08.
Description of the Globalstar System GS-TR-96-0021Revision E6-131User Terminal Gateway(User conversation) (User conversation)•Detects request for third party to beadded to conversation•Sends Flash With InformationMessage (dialed digits)>Reverse TrafficChannel>•Mutes speechOptional Optional•Applies ring back in audio path <Forward TrafficChannel<•Sends Alert With InformationMessage (ring back tone)(Called party answers)Optional Optional•Removes ring back tone from audiopath<Forward TrafficChannel<•Sends Alert With InformationMessage (tones off)•Unmutes speech from added party(Two-way conversation with addedparty; original partyheld)(Two-way conversation with addedparty; original party held)•Detects user request to establishthree-way conversation•Sends Flash With InformationMessage>Reverse TrafficChannel>•Reconnects original party(Three-way conversation) (Three-way conversation)2Figure 6-12. Simple Call Flow, Three-Party Calling Example (TIA Call Control3Procedures)4
Description of the Globalstar System GS-TR-94-0001Revision E6-141User Terminal Gateway(User conversation with first party) (User conversation with first party)•Detects incoming callOptional Optional•Applies call waiting tone in audiopath<Forward TrafficChannel<•Sends Alert With InformationMessage (call waiting tone)•Detects user request to changeparties•Sends Flash With InformationMessage>Reverse TrafficChannel>•Mutes speech path to first party,connects second party(User conversation with second party;first party held)(User conversation with secondparty; first party held)•Detects user request to changeparties•Sends Flash With InformationMessage>Reverse TrafficChannel>•Mutes speech path to secondparty, connects first party(User conversation with first party;second party held)(User conversation with first party;second party held)2Figure 6-13. Simple Call Flow, Call-Waiting Example (TIA Call Control Procedures)34Figure 6-14 illustrates call processing operations during a soft handoff from pilot A to pilot B. Figure 6-515 illustrates call processing operations during a sequential soft handoff in which the user terminal is6transferred from a pair of pilots A and B through a pair of pilots A and C to pilot C. All the handoff call7processing procedures described below are the same for both the TIA and the ETSI call control and8mobility management procedures.9
Description of the Globalstar System GS-TR-96-0021Revision E6-151User Terminal Gateway(User conversation using A) (User conversation using A)•Sends Pilot Strength MeasurementMessage>Reverse TrafficChannel>•Receives Pilot StrengthMeasurement MessageGW decides to begin handoff tochannel B.•Begins transmitting traffic on theForward Traffic Channel on B•Receives Handoff DirectionMessage<Forward TrafficChannel<•Sends Handoff Direction Messageto use A and B•Acquires B; begins using ActiveSet {A,B}•Sends Handoff CompletionMessage>Reverse TrafficChannel>•Receives Handoff CompletionMessage•Handoff drop timer of pilot Aexpires•Sends Pilot Strength MeasurementMessage>Reverse TrafficChannel>•Receives Pilot StrengthMeasurement MessageGW decided to cancel channel A•Receives Handoff DirectionMessage<Forward TrafficChannel<•Sends Handoff Direction Messageto use B only•Stops diversity combining; beginsusing Active Set {B}•Sends Handoff CompletionMessage>Reverse TrafficChannel>•Receives Handoff CompletionMessage•Stops transmitting on the ForwardTraffic Channel using A(User conversation using B) (User conversation using B)2Figure 6-14. Call Processing During Soft Handoff3
Description of the Globalstar System GS-TR-94-0001Revision E6-161User Terminal Gateway(User conversation usingA and B)(User conversation usingA and B)•Sends Pilot Strength MeasurementMessage>Reverse TrafficChannel>•Receives Pilot StrengthMeasurement Message, determinesthat new Active Set should containB and C•Begins transmitting traffic on theForward Traffic Channel using C•Receives Handoff DirectionMessage<Forward TrafficChannel<•Sends Handoff Direction Messageto use B and C•Stops diversity combining A and B;starts diversity combining B and C•Sends Handoff CompletionMessage>Reverse TrafficChannel>•Receives Handoff CompletionMessage•Stops transmitting on the ForwardTraffic Channel using A•Sends Pilot Strength MeasurementMessage>Reverse TrafficChannel>•Receives Pilot StrengthMeasurement Message(Continues) (Continues)2Figure 6-15. Call Processing During Sequential Soft Handoff3(Part 1 of 2)4
Description of the Globalstar System GS-TR-96-0021Revision E6-171User Terminal Gateway(Continues) (Continues)•Receives Handoff DirectionMessage<Forward TrafficChannel<•Sends Handoff Direction Messageto use C only•Stops diversity combining; beginsusing Active Set {C}•Sends Handoff CompletionMessage>Reverse TrafficChannel>•Receives Handoff CompletionMessage•Stops transmitting on the ForwardTraffic Channel using B(User conversation using C) (User conversation using C)2Figure 6-16 Call Processing During Sequential Soft Handoff3(Part 2 of 2)456789

Navigation menu