Global Microwave Systems VMT-F2 Digital 100mW Transmitter User Manual 100 M0169Xmods

Global Microwave Systems, Inc. Digital 100mW Transmitter 100 M0169Xmods

User Manual

                                                                                                                                                                           Cobham Surveillance                     GMS Products                            1916 Palomar Oaks Way Ste 100                     Carlsbad, CA 92008 100-M0169X1  11-15-11                                                                   T: 760-496-0055                                                               F: 760-496-0057 www.cobham.com/gms         Technical Operations Manual The most important thing we build is trust.    VETA Miniature Transmitter  (VMT)
  REVISION HISTORY  Version Date Author Comments X1 11/15/11 Thad Giotta Initial release FCC version VMT ISM band
  100-M0169X1  11-15-11                                         3 of 24  www.cobham.com/gms    Table of Contents  1.0 Information to User ................................................................................................................................................................ 5 2.0 Important Warning and General Safety Information .......................................................................................................... 6 3.0 Acronyms ................................................................................................................................................................................ 8 4.0 Introduction ............................................................................................................................................................................ 9 4.1 Key System Features ....................................................................................................................................................... 10 4.2 Warranty ........................................................................................................................................................................... 10 4.3 Safe Operating Procedures .............................................................................................................................................. 10 5.0 General System Information ............................................................................................................................................... 11 5.1 Getting Started ................................................................................................................................................................. 11 5.2 Initial Checkout ................................................................................................................................................................. 11 5.2.1 Initial Checkout of VMT ........................................................................................................................................... 12 5.2.2 Setup of Corresponding VETA Receiver ................................................................................................................. 13 6.0 Hardware Overview .............................................................................................................................................................. 15 6.1 VMT Interface Connectors ............................................................................................................................................... 15 6.1.1 RF Out ........................................................................................................................................................................ 15 6.1.2 I/O .............................................................................................................................................................................. 15 6.2 Local Control ..................................................................................................................................................................... 17 6.2.1 Set-Up Group Select Switch .................................................................................................................................... 17 7.0 Remote Control of VMT ....................................................................................................................................................... 18 7.1 VETA Remote Control Unit – VRCU ................................................................................................................................ 18 8.0 Software Overview ............................................................................................................................................................... 19 9.0 VETA Chaining Feature ........................................................................................................................................................ 20 9.1 VETA Digital Repeater (VDR) .......................................................................................................................................... 20 9.2 Compact Surveillance Modem (CSM) ............................................................................................................................. 20 9.3 UDP Transmitter .............................................................................................................................................................. 20 10.0 Specifications ........................................................................................................................................................................ 21 10.1 COFDM RF Output ........................................................................................................................................................ 21 10.2 Modulation .................................................................................................................................................................... 21 10.3 Video Encoding ............................................................................................................................................................. 21 10.4 Audio Encoding ............................................................................................................................................................. 21 10.5 RS232 Data Input .......................................................................................................................................................... 22 10.6 Security Option ............................................................................................................................................................. 22 10.7 Physical ......................................................................................................................................................................... 22 10.8 Environmental .............................................................................................................................................................. 22 10.9 DC Power ....................................................................................................................................................................... 22 10.10 Control ........................................................................................................................................................................... 22
  100-M0169X1  11-15-11                                         4 of 24  www.cobham.com/gms    List of Tables  Table 1 RF Connector ........................................................................................................................................................................ 15 Table 2 JST Connector (21 Pins) ....................................................................................................................................................... 16 Table 3 Rotary Switch Configurations ............................................................................................................................................... 18    List of Figures  Figure 5.1  Basic VDL Setup ............................................................................................................................................................. 11 Figure 5.2  VMT RF Essentials .......................................................................................................................................................... 13 Figure 6.1 VMT Interface Connectors ............................................................................................................................................... 15 Figure 6.2 VMT with Rotary Switch ................................................................................................................................................. 17 Figure 7.1  VETA Remote Control Unit ............................................................................................................................................ 18    List of Appendixes  Appendix A:  Standard Breakout Cable .......................................................................................................................................... 23
  100-M0169X1  11-15-11                                         5 of 24  www.cobham.com/gms    1.0 Information to User  This  device  complies  with  Part  15  of  the  FCC  Rules.  Operation  is  subject  to  the  following  two conditions: (1) This device may not cause harmful interference, and  (2) This device must accept any interference received, including interference that may cause undesired operation.  This  equipment  has  been  tested  and  found  to  comply  with  the  limits  for  Class  B  Digital  Device, pursuant  to  Part  15  of  the  FCC  Rules.    These  limits  are  designed  to  provide  reasonable  protection against harmful interference in a residential installation.  This equipment generates and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.  However, there is no guarantee that interference will not  occur  in a  particular installation.   If  this equipment  does cause  harmful interference to  radio or television  reception,  which  can  be  determined  by  turning  the  equipment  off  and  on,  the  user  is encouraged to try to correct the interference by one or more of the following measures:  • Reorient or relocate the receiving antenna • Increase the separation between the equipment and receiver • Connect the equipment into an outlet on a circuit different from that to which the receiver is connected • Consult the dealer or an experienced radio/TV technician for help
  100-M0169X1  11-15-11                                         6 of 24  www.cobham.com/gms    2.0 Important Warning and General Safety Information  The following information is presented to the operator to ensure awareness of potential harmful RF (radio  frequency)  exposure  and  general  hazards.    With  regards  to  potential  harmful  RF electromagnetic fields the text below is only a brief summary highlighting the possible risks and how to minimize  exposure.    The  summary  is  based  on  OET  Bulletin  65  “Evaluating  Compliance  with  FCC Guidelines  for  Human  Exposure  to  Radiofrequency  Electromagnetic  Fields” (1).  The  user  should carefully read and comprehend the following before operating the equipment. For additional in depth information refer to OET Bulletin 65.  1. FCC has set guidelines (1) for evaluating exposure to RF emissions that the user must be aware of  when  operating  the  VMT  (VETA  miniature  transmitter)  microwave  transmitter.    The maximum  power  density  allowed  at  2412-2472MHz  is  5mW/cm2  for  occupational/controlled exposure* and 1mW/cm2 for general population/uncontrolled exposure**.  These are the limits for  maximum  permissible  exposure  (MPE)  as  called  out  in  the  FCC  guidelines  (for  the  above mentioned frequencies). 2. Exposure is based upon the average time spent within the RF field with a given intensity (field units  in  mW/cm2).   Hence  it  may  be  controlled  (or  at  least  minimized)  by  observing  the  safe distances and time exposed. Safe distances are calculated from equations predicting RF Fields (3). 3. The  transmitter  is  a  mobile  device,  is  rated  at  0.1W  (+20dBm)  RF  power  and  is  capable  of harmful radiation if safe operating practices are not observed.    *”Occupational/controlled exposure limits apply to situations in which persons are exposed as a consequence of their employment and in which those persons who are exposed have been made fully aware of the potential for exposure and can exercise control over their exposure.  Occupational/controlled exposure limits also apply where exposure is of a transient nature as a result of incidental passage through a location where exposure levels may be above general population/uncontrolled limits (see below), as long as the exposed person has been made fully aware of the potential for exposure and can exercise control over his or her exposure by leaving the area or by some other appropriate means……..” (2) ** “General population/uncontrolled exposure limits apply to situations in which the general public may be exposed or in which persons who are exposed as a consequence of their employment may not be made fully aware of the potential for exposure or cannot exercise control over their exposure.  Therefore, members of the general public would always be considered under this category when exposure is not employment-related, for example, in the case of a telecommunications tower that exposes persons in a nearby residential area.“ (2) (1) OET Bulletin 65, Apendix A Table 1 Limits for MPE http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet65/oet65.pdf (2) OET Bulletin 65, page 9, definitions of types of exposure http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet65/oet65.pdf (3) OET Bulletin 65, page 19, Equations for predicting RF Fields http://www.fcc.gov/Bureaus/Engineering_Technology/Documents/bulletins/oet65/oet65.pdf
  100-M0169X1  11-15-11                                         7 of 24  www.cobham.com/gms    4. Antenna minimum safe  operating distance is 20cm  (8 inches).  It  is the responsibility of  the qualified end-user of this intentional radiator to control the safe distances and exposure limits to bystanders. 5. Do not substitute any antenna for the one supplied or recommended by the manufacturer. The installer is responsible for ensuring that the proper antenna is installed. 6. It should be noted that this device is an intentional radiator, hence:   Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate the equipment.  NOTE:    The  manufacturer  is  not  responsible  for  any  radio  or  TV  interference  caused  by unauthorized  modifications  to  this  equipment.  Such  modifications  could  void  the  user’s authority to operate the equipment.  7. DC  power  (+12VDC  nominal)  to  the  unit  should  never  be  applied  until  the  antenna  (or  other suitable  load)  has  been  attached  to  the  device  SMA  RF  output  connector.  Safe  operating procedures must be observed when unit is transmitting into an antenna. 8. Electro-Static Discharge (ESD) precautions should be observed as a safe practice. 9. The  transmitter  will  generate  considerable  heat  and  is  the  responsibility  of  the  end  user  to properly heat sink the device before using.
  100-M0169X1  11-15-11                                         8 of 24  www.cobham.com/gms      3.0 Acronyms  This section lists and describes the various acronyms used in this document.  Name  Meaning 16QAM  16-state Quadrature Amplitude Modulation 64QAM  64-state Quadrature Amplitude Modulation A/V  Audio/Video AES  Advanced Encryption System  ABS  Basic Encryption System (8 bit) COFDM  Coded Orthogonal Frequency Division Multiplexing CVBS  Composite Video D/C  Down-Converter FEC  Forward Error Correction GUI  Graphical User Interface I/O  Input/ Output KBaud  Kilobaud per second Kbps  Kilobits per second Mbps  Megabits per second MER  Modulation Error Rate MPEG  Moving Picture Experts Group NTSC  National Television System Committee PAL  Phase Alternation Line QPSK  Quadrature Phase Shift Keying RF  Radio Frequency RX  Receiver S/N  Signal-to-Noise Ratio THD  Total Harmonic Distortion TX  Transmitter UDP  User Datagram Protocol VDC  Volts (Direct Current) VDL  VETA Digital Link VETA  Very Efficient Transmission Apparatus  VMT  VETA Miniature Transmitter  VNA    VETA Network Adapter  VR  VETA Receiver VT  VETA  Transmitter
  100-M0169X1  11-15-11                                         9 of 24  www.cobham.com/gms     4.0  Introduction   GMS’  Very  Efficient  Transmission  Apparatus  (VETA)  product  line  enables  the  user  to  build  wireless digital  microwave  video  systems.  The  VETA  product  line  provides  several  key  features  that  enable high-quality and low-latency wireless Audio/Video (A/V) transmission for the most demanding short or long distance point–to–point or point to multipoint transmission applications. VETA transmitters are suitable for applications where size, weight, latency, security and power consumption are critical.   The  VETA  Links  use  a  digital  modulation  system  known  as  Coded  Orthogonal  Frequency  Division Multiplexing (COFDM) that provides a robust link immune to multipath interference to provide crisp, clear pictures in the most difficult of terrains. The VETA product line employs the standard DVB-T 2K carriers  COFDM  technology.  Additionally,  an  optional  1.25MHz  and  2.5MHz  RF  bandwidth  with  400 carriers may be user selected that allow a larger quantity of simultaneous A/V links to operate in the same  frequency  band.  The  2.5MHz  and  1.25MHz  bandwidth  technology  demonstrates  better propagation for longer range links.   One  of  the  biggest  problems  encountered  in  the  transition  from  analog  to  digital  A/V  systems  has been the inherent digital coding/decoding delays that in some digital systems are 400ms or more. The VETA  Transmitters  &  Receivers  employ  internal MPEG-2  or  MPEG-4  (User  Selectable, MPEG-4  only selectable  for  2.5MHz  and  1.25MHz  Bandwidths)  Encoders  and  Decoders  with  specially  designed coding  technology,  which  provides  an  end  to  end  video  link  without  the  introduction  of  any  further MPEG encoding artifacts. This is crucial for certain applications, where personnel are reacting to real-time events.   The VMT is a VETA Miniature Transmitter that has been designed to be as small and power efficient as possible. It is an ideal fit for concealment and body worn applications and small-unmanned vehicles. The  VMT  accepts  a  composite  or  S-Video  Input,  Analog  Stereo  Audio  Inputs  (with  MIC  Bias)  and  a RS232 User Data Input. There is also an option to accept SDI Video. The Video is compressed according to  MPEG-2  or  MPEG-4  (Optional) specifications. The  Audio  is sampled  and  compressed.  The Audio, Video and Data packet streams are multiplexed with basic service data to indicate the service name. The stream can be scrambled with a simple fixed key scrambling system (ABS standard) to give basic protection  in  sensitive  applications.  Additional  security  is  accomplished  with  the  optional  AES scrambling system. The transport stream is sent for FEC pre-processing and COFDM modulation. The modulated signal is amplified and output through a SMA-F connector.   This manual provides information on how to operate the VMT (VETA Transmitter) as well as pertinent technical information related to the overall system.
  100-M0169X1  11-15-11                                         10 of 24  www.cobham.com/gms    4.1  Key System Features  • COFDM Modulation : 2K  or 400 (1) Carriers • Bandwidths: 6 MHz, 7 MHz or 8 MHz   (1.25 & 2.5 MHz optional) • Output Frequency: 2412-2472MHz • Output Power: 100mW • Built-in MPEG-2/MPEG-4 (2) Encoder  • Low End to End System Latency (3) (down to ~44mS) • Rugged Compact Design: 2.7” x 1.6” x 0.5” (6.9cm x 4.0cm x 1.3cm) • Secure – ABS and AES 128/256(4)   (1)  400 carriers is optional with the 1.25 or 2.5MHz RF bandwidth upgrades (2) MPEG-4 is optional and included with the 1.25MHz upgrade.  MPEG4 optionally used in 1.25MHz and 2.5MHz modes. (3)     With  DVB-T  standard  BWs.    ~120mS  system  latency  in  1.25  &  2.5  MHz  Bandwidths  depending  on  modulation parameters (4)   AES 128 or 256 bit encryption is optional  4.2  Warranty  GMS offers a 12-month standard product warranty. During this period, should the customer encounter a fault with the equipment we recommend the following course of action:    If fault persists, call our support line and report the fault. If fault persists and you are informed to  return  the  product,  please  obtain  an  RMA  number  from  the  GMS  support  department  or website and ship the equipment with the RMA number displayed and a description of the fault. Please email the support section the airway bill/consignment number for tracking purposes.   Depending  on  the  nature  of  the  fault,  GMS  endeavor  to  repair  the  equipment  and  return  it  to  the customer within 14 days of the item arriving at our workshops. Obviously, it is impossible to cater for all  types  of  faults  and  to  manage  100%  replacement  part  availability,  and  delays  are  sometimes inevitable.  Please  contact  GMS  for  details  of  packages  that  can  be  tailored  to  meet  your  individual  needs, whether they are service availability, technical training, local geographic support or dedicated spares holdings.   4.3  Safe Operating Procedures  •  Ensure that the power supply arrangements are adequate to meet the requirements of VETA product. •   Operate within the environmental limits specified for the product. •   Only  authorized,  trained  personnel  should  open  the  product.  There  are  no  functions  that require the User to access the product’s interior.
  100-M0169X1  11-15-11                                         11 of 24  www.cobham.com/gms    5.0 General System Information  5.1  Getting Started  The Standard VMT kit includes the following items: • VMT Unit • VMT Breakout Cable (GMS p/n 780-C0449*) (Power, Composite Video, Audio , RS232 Control)  NOTE:  Based  on  customer  applications  GMS  can  deliver  a  receiving  system,  additional  cables  and antennas.  Contact GMS for further information  The VMT is pre-configured by GMS prior to shipment (based on customer requirements), thus is ready to work “right out of the box”.  5.2  Initial Checkout  Prior to installing a VMT into the desired target environment, an initial checkout should be performed to ensure proper operation of the unit.  The initial checkout described below consists of configuring a basic VETA Digital Link (VDL).  In the case outlined, we will assume a VETA Receiver (VR) is used to receive the VMT.  Note, that any DVB-T compliant receiver can be employed instead if the VMT is set-up in standard DVB-T Mode (RF BW 6, 7, or 8 MHz) and not in ultra-low delay mode.      Figure 5.1  Basic VDL Setup
  100-M0169X1  11-15-11                                         12 of 24  www.cobham.com/gms    The following setup can be done, either wirelessly with antennas, or through hard line connection with  50Ω  cable.   In  either  case,  make  sure there  is  enough  attenuation from  the Tx to  the Rx to avoid overdriving the receiver.  In most DVB-T receivers, their optimal input power ranges from -30 to -70 dBm.  The VR shown has internal BDCC installed locally within unit, which is our standard VR configuration. 5.2.1  Initial Checkout of VMT  • Install Omni-directional antennas (or ones best suited for the  application) onto the  RF  IN A  and RF IN B ports on the VETA Receiver (or equivalent DVB-T Receiver) and one on the SMA RF connector on the VMT transmitter.  Note: As a rule, transmitters should not be powered on without a load attached to the RF output connector. • Attach  the  VMT  standard  breakout  cable  (or  customer  equivalent),  780-C0449*  to  the  Tx.  Apply +12VDC to the red pigtail and GND to the black pigtail. Ensure power supply can supply at least 0.4A at +12VDC (Note: The VMT can operate over 5.9-18VDC range). • Attach  a  composite  video  source  to  the  BNC  video  input  cable  that  is  located  on  the  VMT breakout cable. Make  sure that the source video is powered on and outputting the video in the desired format (PAL or NTSC) and input port (Composite #1 or #2 or SDI). • Connect the RS232 Control of the VMT to the corresponding serial port of the PC.  Open the GMS configurator software (see VETA Miniature Transmitter Software Manual, 100-M0130, for control software details).   • If the TX receives the source video signal, the Video Locked Status indicator will show: “YES.”  If the Video Locked Status shows “NO,” check the connection of the Video source, verify that the video source is indeed active, and click the “Query” button.  Verify that the Video source matches the “Video Input” selection.  If the source is NTSC, then the VMT “Video Input” should show “NTSC.” • Next, note which VMT Configuration is active, 1 through 16 under the Load Config pull down window.    This  number  must  match  the  receiver  configuration,  which  assumes  all configurations  have  matching  parameters.    Also  verify  that  the  Output  Mode  shows  “ON,” otherwise  the  RF  section  of  the  VMT  will  be  shutdown  and  no  RF  transmission  will  be possible. • This completes the initial setup of the VMT for Video transmission and RF testing.  5.2.1.1 Key RF settings For COFDM Transmission   The RF settings shown in Figure 3.2 show the key COFDM configurations for setting up any COFDM  link.    The  settings  underlined  in  RED  must  be  matched  specifically  to  the  VETA Receiver  for  proper  RF  lock  and  demodulation  (the  other  COFDM  parameters  are  auto-detected).  In general, when troubleshooting a RF link, the operator should make sure that the following RF parameters are matched at both the Transmitter and Receiver.
  100-M0169X1  11-15-11                                         13 of 24  www.cobham.com/gms     Figure 5.2  VMT RF Essentials  5.2.2  Setup of Corresponding VETA Receiver  • Attach a video cable from BNC VID output port on the VR (Veta Receiver) to the composite input of the video monitor. • Apply  +12Vdc  to  the  VR,  pins  1,  2,  +12V  and  3,  4  ground  to  the  J2  dB  connector  (if  using provided  cable  use  the  red  (+12V)  and  black  (GND)  pigtails.  Power  supply  must  be  able  to source 2 AMP at 12VDC.  • Turn on the video source and video monitor equipment. • Turn on the VR with the PWR switch on the front panel (up is ON). • Ensure  the  selected  configuration  matches  that  of  the  transmitter.    If  not,  use  the  VETA Receiver configurator to select or modify the configuration, see Figure 3.2 for VMT settings to match to the VR. • Once the VR has powered-up, ensure that the Config LED is light solid green.  If not, press the RF button on the front keypad (this action provides power to the internal down converters) so that corresponding Config LED is solid green. • Press the MODE button on the Front Panel to turn on the diagnostic OSD (on screen display) for the video monitor. • After  approximately  5  seconds,  the  link  should  be  established  and  video  provided  by  the source should  be displayed on the  monitor. On the  Receiver side, the green RF LED  should light as well as the Signal Strength indicators.  The OSD should show lock onto the incoming signal with a corresponding power level and SNR on the two receive inputs. • If  the  red  Alarm  LED  lights  it  may  be  an  indication  that  the  receiver  is  unable  to  lock  to  a signal. Check the following:  Ensure the receiver and transmitter have matching RF configurations, see Figure 3.2.   Ensure the transmitter Output Mode is “ON.”    If  the TX  and  RX  are  physically  too close  to each  other,  the RX  may overload  causing distorted  Video.    If  the RF  power  sensed  by  the  VR  is  greater  than  -20dBm,  you  may want to reduce the power out of the TX (using RF attenuators) or physically move the TX & RX further apart. 2412.00
  100-M0169X1  11-15-11                                         14 of 24  www.cobham.com/gms     Conversely, the power level to the VR may be too low for RF lock and demodulation.  If the RF power sensed by the VR is less than -80dBm, you may want to increase the RF power  to  the  VR.    Either  decrease  the  RF  attenuation  between  the  Tx  and  Rx  or physically move the two closer to one another.  The initial checkout described above is simply to check the basic video operation of the VMT unit.  For further details on the connectors, monitoring and controlling the VMT read thoroughly through this manual.
  100-M0169X1  11-15-11                                         15 of 24  www.cobham.com/gms    6.0  Hardware Overview  The VMT consists of a rotary switch along with interface connectors.    6.1  VMT Interface Connectors  The VMT interface connectors consist of a RF SMA, and a 21 PIN JST connector. They are described in this section.  6.1.1  RF Out The RF output consists of a female SMA connector.   Connector Type Comments SMA (F) Antenna connects here Table 1 RF Connector  Figure 6.1 VMT Interface Connectors 6.1.2  I/O  The VMT ‘I/O’ connector is a dual row twenty one (21) pin JST, JST part number: SM21B-SHLVS-G-TB(LF).    A  GMS  breakout  Cable,  #780-C0449  is  provided  for  testing.    It  is  used  to  provide  the interface for external power, audio (with phantom biasing for Tibbetts microphones), analog video and RS232 control.  The pin out for the I/O connector is shown in Table 2 below.  PIN SIGNAL NOTES 1  SDI VIDEO IN SD-SDI  Video  Input.    This  is  an optional  upgrade.    Must  be  selected with GMS Control Software. 2 GND GND 3  CHAIN CLK IN N/C.    Chaining  used  in Repeater/Multiplexing    applications, contact GMS for details 4  CHAIN DATA IN N/C.    Chaining  used  in Repeater/Multiplexing    applications, contact GMS for details RF Out, Ant Port  I/O JST-21 Connector Pin Out  Rotary Switch
  100-M0169X1  11-15-11                                         16 of 24  www.cobham.com/gms    PIN SIGNAL NOTES 5 AUDIO GND AUDIO GND 6  COMP INPUT 1 Composite  Video  Input.    Must  be selected  with  GMS  Control  Software. Also used for S-VIDEO Input.   7  COMP INPUT 2 N/C.   Only  used  for  S-VIDEO  Input.  Must  be  selected  with  GMS  Control Software. 8 GND GND 9 AUDIO LEFT Audio Left, W/ 2V Phantom Bias. 10 AUDIO RIGHT Audio Right, W/ 2V Phantom Bias. 11 GND GND 12  CHAIN CLK OUT* N/C.   Chaining  used  in Repeater/Multiplexing    applications, contact GMS for details 13  CHAIN DATA OUT* N/C.   Chaining  used  in Repeater/Multiplexing    applications, contact GMS for details 14 GND GND 15 RS232_DATA_Rx N/C.  RS232 for User Data, Rx 16 RS232_DATA_Tx N/C.  RS232 for User Data, Tx 17 RS232_CNTRL_Rx RS232 for PC CONTROL Software 18 RS232_CNTRL_Tx RS232 for PC CONTROL Software 19 2.8V uC N/C.  2.8V Output from Unit 20 GND GND 21 VBATT_IN Input Power to Unit: 5.9-18VDC Table 2 JST Connector (21 Pins)    Note:    Table  2  references  Cable  780-C0449.    GMS  can  build  customized  cables  to customer  specifications  to  access  functionality  not  included  in  our  standard  cable.  Customers can also choose to build their own cables. Contact GMS with any questions.   6.1.2.1 Phantom Bias for TIBBETTS Microphones  The VMT does not provide a traditional separate bias voltage for surveillance microphones.  Instead, we provide a 2V Microphone BIAS directly on the signal lines.  This is called phantom biasing  of  microphones  and  has  been  proven  to  work  with  TIBBETTS  151/251/351  series microphones by GMS.  See TIBBETTS technical application notes for Phantom powered  2-wire connection for specific details, GMS standard breakout cable employs 2-Wire Option C.  This wiring is in accordance with section 4.9.2 of RFP: E007216R and Attachment A of RFP: E007216R.  In addition, to note, single ended line level audio can also be used instead of microphones.  The user will want to lower the Audio Gain to “0dB” through the GMS control software when Line level audio is input.
  100-M0169X1  11-15-11                                         17 of 24  www.cobham.com/gms         6.2  Local Control 6.2.1  Set-Up Group Select Switch  How to Operate    There  is  one  16  position  external  rotary  switch  mounted  into  the  chassis  for  the  VMT (reference Figure 6.2)   Figure 6.2 VMT with Rotary Switch  The  switch  is  used  to  control  set-up  group  selection.  Set-up  group  selection  can  also  be controlled through GMS control software configurator GUI (refer to the Software Manual, 100-M0143).  As previously stated, administrators define the set-up groups for specific applications. Each set-up group completely defines all of the transmitter’s set-up parameters including center frequency,  output  RF  power  level,  modulation  parameters,  video,  audio,  user  data  and encryption.  Each  set-up  group  can  be  completely  different  from  any  other  group.  Field personnel  will  select  specific  set-up  groups  via  pre-determined  guidance  from  the administrators. Matching the transmitter operation to the receiver operation is as simple as selecting the same set-up groups. For example: If the transmitter is set to preset #4, then the receiver needs to be set to preset #4 for them to operate together.  The Rotary Switch is in Hexadecimal format, representing the 16 configurations.  While the switch  is  in  hexadecimal  the  control  software  is  shown  in  decimal  format,  see  Table  3.  Because the switch is in binary format, the first setting begins at zero.  Rotary Switch Position Configuration # (Decimal Value)
  100-M0169X1  11-15-11                                         18 of 24  www.cobham.com/gms    Rotary Switch Position Configuration # (Decimal Value) 0  1 1  2 2  3 3  4 4  5 5  6 6  7 7  8 8  9 9  10 A  11 B  12 C  13 D  14 E  15 F  16 Table 3 Rotary Switch Configurations  7.0  Remote Control of VMT  The VMT can be configured with GMS’ RS232 VETA Remote Control Unit (VRCU).    7.1  VETA Remote Control Unit – VRCU  In addition to being able to select a set-up group by  using the rotary switch on the VMT, a RCU, remote control unit, is available.  The RCU is a small hand–held remote control unit designed for serial control of the VMT transmitter.  It allows the operator to access all features of the transmitter on a two-wire RS-232 connection.  For details, see the on-line manual: 100-M0104.   Figure 7.1  VETA Remote Control Unit
  100-M0169X1  11-15-11                                         19 of 24  www.cobham.com/gms     8.0  Software Overview  Configuration, control and monitoring of the VMT units are done by using GMS’ MS Windows-based VMT  Configurator  software  program  100-SW0070.    This  Graphical  User  Interface  (GUI)  program provides  the  end  user  with  a  straightforward  way  to  interface  with  the  VMT  unit.    During  normal operation, once a link is established, the VMT Configurator GUI does not need to be active and can be disconnected from the VMT unit.   Refer to the Software Manual, 100-M0143, for further information.
  100-M0169X1  11-15-11                                         20 of 24  www.cobham.com/gms    9.0 VETA Chaining Feature  The VETA series of products use a  Proprietary Transport stream  protocol called ‘Chaining’ to create the VDR (VETA Digital Repeater), the CSM (Compact Surveillance Modem) or a UDP Tx.  This is all available by utilizing the chaining feature that comes standard on all VETA Tx, VR and VNA.  Contact the factory for more information about the Chaining feature and the variety of applications it can be employed with.  9.1  VETA Digital Repeater (VDR)  An  In band  or cross  band  repeater  can  be  made  very simply  with the  VETA  series Transmitter (VT-2W, VT-C,  VT-L, or VMT) in conjunction with a VETA Receiver (VR).  The user simply has to connect the ‘Chaining Out’ of the VR into the ‘Chaining In’ of a VETA Tx.    9.2  Compact Surveillance Modem (CSM)  The  VETA  Compact  Surveillance  Modem  is  much  like  the  VDR  with  the  addition  of  the  VETA NETWORK ADAPTOR (VNA).  The VNA allows for IP streaming of video, or with a complement CSM a LAN Bridge (CSB) can be created across the link.    9.3  UDP Transmitter    A UDP transmitter can easily be employed using the Chaining Out of a VNA into the Chaining In of a VETA Tx.  UDP can be sent to the VNA via the RJ45 connector that is converted to Chaining within the VNA and delivered to the VETA Tx through the Chaining interface.  On the receiver Side, a VR will send its Chaining Out to the Chaining In of a VNA.  The VNA can be connected to a router or simply another computer to distribute the UDP data.
  100-M0169X1  11-15-11                                         21 of 24  www.cobham.com/gms     10.0   Specifications  10.1  COFDM RF Output Output Frequency: 2412-2472MHz (ISM Band) Bandwidth: Selectable 6, 7, 8 MHz (1.25 & 2.5 MHz Optional)  RF Output Power: Programmable up to 100 mW  Connector: SMA-F Frequency Stability:  +/-2 ppm,  Output Impedance: 50Ω, unconditionally stable, open & short circuit protected Harmonics: <-25 dBm  10.2  Modulation Modulation Type: COFDM 2K: QPSK, 16QAM  FEC: 1/2, 2/3, 3/4, 5/6, 7/8 Guard Intervals: 1/32, 1/16, 1/8, 1/4 Optional Narrow Band (1.25 & 2.5 MHz BW) Modulation Type: C-OFDM 400: QPSK, 16QAM FEC: 1/3, 2/3,  Guard Intervals: 1/16, 1/8 Spurious > 52dBc   10.3  Video Encoding Video Input: Composite, S-Video Standards: NTSC or PAL   SDI option available Compression Standard: MPEG-2 or MPEG-4 Chrominance Profile: 4:2:0 or 4:2:2 Line Standard: 525 and 625 Horizontal Resolution: 704, 528, 480 or 352 pixels Vertical Resolution: 576 (625 line) and 480 (525 line) Systems Latency end to end delay: Down to ~40 ms  10.4  Audio Encoding Analog Audio Inputs: Dual, Line Level or Mic Level, Single Ended, Clip Level 12 dBm (Mic connection via breakout cable) Compression Type: MPEG  or NICAM (User Selectable) NICAM AUDIO Bits per Sample: 12 or 8 Sampling Frequency: 32 KHz, 16 KHz or 8 KHz MPEG AUDIO             Compression Standard: ISO/IEC 13818-3             Bit rates: Up to 448 kbit/s/ch             Sampling Frequency: 32 kHz or 48KHz Mic Bias: 2V
  100-M0169X1  11-15-11                                         22 of 24  www.cobham.com/gms    10.5  RS232 Data Input Baud Rate: Up to 115 KBaud.  10.6  Security Option ABS  is  standard.  The  VMT  can  optionally  be  provided  with  Advanced  Encryption  System  (AES) 128/256 for protecting the signal in sensitive applications.   10.7  Physical Dimensions: 1.6” wide x 2.7” long x 0.5” high             4.0 cm x 6.9 cm x 1.3 cm Weight: 0.114 lbs               52 grams  10.8  Environmental Operational Temperature: -20 to 70 deg C Humidity: Up to 95% non-condensing  10.9  DC Power DC Voltage Range: 5.9 V - 18 V  Reverse Polarity Protection up to 30 V Power Consumption:  Depends on Frequency, typical =4.1W    10.10  Antenna Description Type: Directional Antenna Gain: 2 dBi GMS part # AOS2A02N360FG  10.11  Control Local  –  Easy  to  use  Rotary  Switch  allows  up  to  16  user-defined  operating  modes  covering  most programmable parameters.     Connector - DB-9 (F), RS232 control.
  100-M0169X1  11-15-11                                         23 of 24  www.cobham.com/gms     Appendix A:  Standard Breakout Cable

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