Redline Communications AN50 Access Node User Manual AN 50 v19

Redline Communications Inc. Access Node AN 50 v19

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AN-50 User Manual 26/52 Redline Communications …..solving the first mile challenge. Wireless Configuration: Channel: specifies the operating channel of the system, within the 100 MHz available in the 5.8GHz UNII band. The table below specifies the center frequencies of each permitted channel. Channel Frequency 1 5735 MHz 1A 5745 MHz 2 5755 MHz 2A 5765 MHz 3 5775 MHz 3A 5785 MHz 4 5795 MHz 4A 5805 MHz 5 5815 MHz To avoid interference, two PTP links operating in the same physical location (co-located) or within close proximity (e.g. across the street) must be separated by at least one channel, i.e. the gap between channels should be 20 MHz or more (e.g. channels 1 and 3). Refer to Section 8.5 for further information regarding deployment rules. Tx Power: this parameter specifies the power level of the system, which is preset at the factory and should not be altered. In the event that this parameter needs to be changed, please contact the Redline support team at support@redlinecommunications.com. Adaptive rate: checking this box sets the system to operate in adaptive modulation mode. It is recommended to keep the AN-50 in this mode so that the system can automatically adjust the modulation level to the highest possible data rate based on measured RF performance. The user can define the minimum desired modulation level by setting the Main rate parameter (see next item). If the system meets this data rate, then the “Signal” LED on the front panel will light continuously green. If packet errors exceed one out of a million, then the system will automatically lower the modulation level to maintain the link. In this case, the LED will flash green. If errors continue when the system reaches the lowest modulation level, then the LED will flash red to indicate a failed RF link. The user can also disable the dynamic modulation mode by unchecking the Adaptive rate box. In this mode, the user is required to set the Main rate and the Rate diff (see below). Refer to Table 1 to determine which modulation level can be used based on the measured signal to noise ratio.

AN-50 User Manual 27/52 Redline Communications …..solving the first mile challenge. It is recommended not to operate the system in manual mode, as this mode is intended primarily for field support. Note the “Signal” LED will light solid green when the packet error rate is less than 1 out of a million. When the errors exceed this limit, the LED will not illuminate, indicating the RF link has failed. Main rate [Mb/s]: Defines the desired net data rate for the link. Rate dif.: applies when the Adaptive rate is disabled. Rate dif specifies how many levels the system must drop in modulation before beginning re-transmission to address packet errors. The Rate diff value can be set from 1-7, with 2 being the typical value. Master: Sets the AN-50 system to serve as the Master system, while the other AN-50 assumes a slave role. Version: Specifies the current version of the system software. Note, software can be remotely downloaded into the AN-50. The system comprises sufficient memory to hold two independent software loads – the operator can specify which load to download into the system. Peak Transmitted Power per channel and modulation The maximum conducted power is limited by the software / firmware to limit the maximum power for each channel. According to the rating showed in the following table based on direct measurements the maximum power for each channel isn’t user modifiable: PEAK TRANSMIT POWER (Measured a Peak Power Meter) (dBm) Transmitted Channel Frequency (MHz) 64QAM (54 Mb/s) 16QAM (36 Mb/s) QPSK (18 Mb/s) BPSK (9 Mb/s) 1 5.735 -7.4 -7.4 -7.4 -7.4 1A 5.745 16.6 16.6 16.6 16.6 2 5.755 17.3 17.3 17.3 17.3 2A 5.765 20.0 20.0 20.0 20.0 3 5.775 20.5 20.5 20.5 20.5 3A 5.785 20.0 20.0 20.0 20.0 4 5.795 17.3 17.3 17.3 17.3 4A 5.805 16.6 16.6 16.6 16.6 5 5.815 -7.4 -7.4 -7.4 -7.4

AN-50 User Manual 28/52 Redline Communications …..solving the first mile challenge. 6.4. Upgrade The upgrade screen, shown in Figure 16, is used to upgrade the existing software load of the AN-50 unit with new software stored in a binary file on the server or host computer. The system uses the Trivial File Transfer Protocol (TFTP) to execute the process. Two input fields have to be filled in by the operator: TFTP Server IP Address and File name. The TFTP Server IP Address is the IP address of the host computer or server that contains the upgraded software in binary format, while File name is the name of the actual binary file. Figure 16 Upgrade screen. After typing the TFTP Server IP Address and File name, press Upload to begin the file transfer. A status screen (see Figure 17) will immediately follow, which displays, in real-time, the number of bytes being transferred from the host computer/server to the AN-50 unit. The upgrade file size is approximately 1 Megabyte, and can take approximately 1-2 minutes to download from the server to the AN-50 memory. Note the AN-50 contains two memory pages for storing the software/firmware binary code images. One memory location holds the current software, while the second memory area is used to store the new software load. Upon successful transfer of the upgrade file, the AN-50 will verify the integrity of the new software load before transitioning its system to the new binary image. If errors were introduced during the transfer process, as a result of say link degradation, then the AN-50 will reject the new software load, and provide a warning that the upgrade was unsuccessful. In this case, the operator will need to repeat the upgrade process. As mentioned previously, the upgrade process can be achieved remotely, using HTTP over the Internet.

AN-50 User Manual 29/52 Redline Communications …..solving the first mile challenge. Figure 17 Status of upgrade file transfer. 6.5. Change Password The default password for the system, set from the factory, is ‘admin’. To change the password, click on Change password from the main menu and apply a new value in the Password field (see Figure 18) using any alphanumeric combination. Note the field is case sensitive and should be up to 16 characters length. A Long Reset – depressing the ‘reset’ button for more that five (5) seconds - will restore the password to admin’. Figure 18 Change Password Screen.

AN-50 User Manual 30/52 Redline Communications …..solving the first mile challenge. 6.6. Log File The Log File screen, shown in Figure 19, provides a display of the last ten (10) messages recorded by the AN-50 describing either system activity or errors that have occurred. Figure 19 Log File Screen. The Log File will also indicate if the following transactions were successfully completed: • Save Configuration – Under the ‘Configuration’ screen. • Upload – Under the ‘Upgrade’ screen. • Change Password – Under the ‘Change Password’ screen. The following provides a brief description of the key messages recorded onto the Log File by the system: Log File Message Description 100-Parameters loaded successfully! All system parameters have been successfully downloaded. 101-Firmware configuration OK! The onboard firmware configuration have been properly setup 102-Ethernet switch configured! The Ethernet port has been properly configured and is operational. 103-Parameters saved successfully! The latest configuration parameters have been successfully saved into the system memory. 104-Upgrade OK! The software upgrade process completed successfully 105-Password change successful! The new password entered in the system was

AN-50 User Manual 31/52 Redline Communications …..solving the first mile challenge. successfully changed. 201-EEPROM corrupted. Def. param. loaded! The memory area containing the system configuration has been corrupted. Default parameters loaded. 202-Error while saving parameters! The latest configuration parameters have not been successfully saved. In this case, repeat the save configuration process to try to resolve the problem. 203-Another upgrade in progress! The system is already in the upgrade mode, in the event the operator inadvertently invoked multiple simultaneous upgrades. 204-Invalid upgrade parameters! The parameter entered is in error. If this message appears, check for typing errors. 205-Upgrade failed! The software upgrade process completed unsuccessfully. 206-Password change unsuccessful! The new password entered into the system was not successful. In this case, repeat the process. 207-Timeout on reading data packet! The system has time-out looking for packets from the host computer or server. Check for obvious problems such as disconnected or faulty cable. 209-TFTP error received! The Trivial File Transfer Protocol (TFTP) routine used to download the software to the AN-50 during the Upgrade process failed. Likely cause is disconnected or faulty cable. 210-Error: TFTP unknown message! The TFTP client received an unknown message. In this case, repeat the upgrade process. 211-Error: while writing flash! While writing the parameters into AN-50 flash memory an unexpected error occur. Try to repeat the process and if the error persist contact Red Line Communications support team. 212-Error firmware configuration! While writing the firmware into AN-50 system memory an unexpected error occur. Try to repeat the process and if the error persist contact Red Line Communications support team.

AN-50 User Manual 32/52 Redline Communications …..solving the first mile challenge. 7. Diagnostics and Troubleshooting This section provides basic diagnostic and troubleshooting steps to help you solve problems that may have occurred with the AN-50. If, after reading this section, you are unable to get the system operating properly, please contact the support team at Redline at support@redlinecommunications.com. Include the model name and serial number of the system (located at the bottom of the unit) in your communication with Redline. Troubleshooting can be performed using the front panel LEDs and the host computer/server connected locally or remotely to the AN-50. 7.1. Diagnostics via the front panel The front panel of the AN-50 comprises key status LEDs, grouped under the headings System, Wireless and Ethernet, to help with first level diagnoses of problems encountered with the unit. Figure 20 Front panel status LEDs. Throughout this section, reference is made to the ‘Reset’ button, which is a micro-switch recessed in the front panel in the System block. Use a small narrow object, such as a paper clip, to depress the button. Depressing the button for less than five (5) seconds is known as a ‘quick reset’, and is equivalent to turning on and off the unit. A quick reset essentially reloads the current configuration software into the system’s processor from the flash memory (long term memory) and restarts the unit. Depressing the ‘reset’ button for more than five (5) seconds executes what is known as a ‘long reset’. A long reset reloads the previously saved operating software load (which may be the manufacturer’s original software load) and restarts the system. Note, the software version that existed in the system before the long reset will have to be reloaded, either locally or remotely. An example of where a reset will help, is in the event that your password or IP address if

AN-50 User Manual 33/52 Redline Communications …..solving the first mile challenge. forgotten. The reset function will simply restore the system back to its original settings. The remainder of this section lists possible problems that may occur and the corresponding remedies. 7.1.1. System Power Check to see if the Pwr LED is solid and green. If no, then power is not getting to the unit. The most probable causes are: Table 1 System Power Diagnostics. Symptom Possible Problem Solution On/Off switch in Off position Turn on switch. Fuse blown Replace fuse. No power (Pwr LED does not illuminate) Power cord disconnected Securely connect cord to terminal and outlet. 7.1.2. System Fault If the Fault LED illuminates solid red, then it is an indication that there is a serious problem with the system software or hardware. A long reset may remedy the problem. If not, then contact the Redline support team. 7.1.3. Wireless Link The Wireless Link LED illuminates solid green when the system is properly communicating with the remote terminal. The LED will flash green when the system is operating below the desired modulation level, but at low packet errors (i.e. less than 1 packet lossed out of 1 million packets). When the LED does not illuminate, it is an indication that there is a problem either in the terminal, radio, host computers/servers, or with the actual propagation path itself. The table below lists some of the potential problems: Table 2 Wireless Link Diagnostics. Symptom Possible Problem Solution Remote terminal is not on or is mal-functioning. Verify operation of remote terminal. No wireless link (Link LED does not illuminate) The propagation path is blocked. Clear path or re-locate antennas

AN-50 User Manual 34/52 Redline Communications …..solving the first mile challenge. Symptom Possible Problem Solution The transceiver is mal-functioning. Repair or replace transceiver. Antenna has moved and is no longer boresight with remote terminal. Re-align antenna Cable between transceiver and antenna or between transceiver and terminal not properly connected. Properly secure cables. Power not getting to the transceiver from the terminal. Repair or replace terminal. 7.1.4. Wireless Signal The Wireless Signal will flash in amber when RF signals (frames) are not being properly received by the transceiver. This may not be a serious problem if the LED only flashes intermittently, however, if it flashes constantly, then the table below summarizes some of the problems that may be occurring. Table 3 Wireless Signal Diagnostics. Symptom Possible Problem Solution Obstructions in the propagation path causing signal degradation. Try to remove obstacles or re-locate antenna. Antenna moved, due to high winds. Re-align antenna. Poor RF Link (Signal LED flashes) Poor cable connection between transceiver and antenna Repair or replace cable. 7.1.5. Ethernet Link The Ethernet Link LED will illuminate green and solid when the LAN connection to the host computer/server or switch/router is properly functioning. If this LED is not on, then the following possible problems may exist: Table 4 Ethernet Link Diagnostics. Symptom Possible Problem Solution

AN-50 User Manual 35/52 Redline Communications …..solving the first mile challenge. Symptom Possible Problem Solution Poor cable connection between terminal and computer/server or between terminal and switch/router. Carefully check all cable connections. Wrong type of Ethernet cable between terminal LAN port and host computer/server or switch/router. If the terminal LAN port is connected to a host computer or server directly, then ensure a straight-through cable is used. Otherwise, to connect the terminal to a switch or router, ensure a crossover cable is used. The auxiliary Network equipment including switch/router, host computer/server, may be malfunctioning. Repair or replace faulty units. Poor Ehternet Link (Link LED off) System processor hang-up Try quick reset or long reset. 7.1.6. Ethernet Collision The Ethernet Col LED flashes amber when packet collisions occur over the LAN. Note, in any shared IP network, it is typical for packet collisions to occur intermittently. However, if the LED flashes constantly, then there is a serious problem somewhere in the LAN connection. Some possible causes are: Table 5 Ethernet Collision Diagnostics. Symptom Possible Problem Solution Poor Collision Link connection. (Col LED flashes) Poor cable connection between terminal and computer/server or between terminal and switch/router. Carefully check all cable connections. 7.2. Troubleshooting via the screen menu The section assumes that the LEDs on the front panel of the AN-50 are indicating normal functionality, i.e. Ethernet - Link is illuminated green and solid. 7.2.1. Home page does not appear If, after trying to log onto the AN-50 terminal(using HTTP commands) the Home Page does not appear on the screen, then several possibilities exist. The first test

AN-50 User Manual 36/52 Redline Communications …..solving the first mile challenge. is to ping the terminal from the host computer by typing in the following text from the command line: >Ping 192.168.25.2 Note the IP address used in this example is the default address supplied by the factory. If the IP address has been changed since then, it is important to use the current address. If the ping test was successful (i.e. the computer was able to send and receive packets with the terminal) then the problem may be with the text that was entered into the HTTP navigator or with the HTTP program itself. Retype the text or re-boot the host computer to try to resolve the problem. If the ping was unsuccessful, then there may be problems with the IP address that you are using. Try retyping the address. If this fails, and it appears you have forgotten the IP address of the terminal, then perform a Long Reset to restore the terminal to the default value. Table 6 Home Page Diagnostics. Symptom Possible Problem Solution Incorrect IP address Perform a ping test from the host computer command line. If the ping test is unsuccessful, then problem is with the IP address. Perform long reset to apply default address. Home Page does not appear Problems with HTTP or host computer. If Ping is successful, then the problem is most likely with the HTTP program or host computer.

AN-50 User Manual 37/52 Redline Communications …..solving the first mile challenge. 8. Fixed Wireless Access Primer 8.1. Introduction This section provides an overview of the design and benefits of a Fixed Wireless Access (FWA) network architecture based on the Redline AN-50 system. There are several advantages of an FWA system over traditional wireline alternatives such as PSTN, ISDN, T1, DSL, cable and Fiber, including: • Greater availability • Lower cost of ownership per link • Higher throughput (with the exception of fiber) • Greater distances • Quicker time to market • Greater portability The Redline AN-50 can be configured as a point-to-point (PTP) or switched PTP (S-PTP) system (Rev 0.7) to provide both backhaul and access distribution services under one infrastructure and management system. The Revision 0.7 product will be a software upgrade to the current version, which can be accomplished remotely. The system functions logically as a transparent bridge, hence, providing all the benefits of a converged IP network, i.e. ‘IP everywhere’. A converged network allows operators to reduce network buildout costs significantly by employing standard IP appliances everywhere, from backbone to end-user. 8.2. Who can benefit from the AN-50? The AN-50 is an ideal solution for: • Carriers • Internet Service Providers (ISPs) • Enterprises • Education and Campuses A) Carriers The AN-50 will provide benefit to both Incumbent and Competitive Local Exchange Carriers (ILECs and CLECs, respectively). Although ILECs own and provide services over wireline infrastructures within a specific geographical area, they are faced with challenges of reaching outlining regions suffering from poor to no services. The ILEC is usually compelled to provide an expensive solution using a series of PTP radio links, with low throughput (e.g. T1) and costly license fees and network interfaces including T1 multiplexers. The AN-50 provides a cost

AN-50 User Manual 38/52 Redline Communications …..solving the first mile challenge. effective alternative, by connecting a remote site from the local CO, as shown in see Figure 21. Fiber RingRemoteC.O./POPLocalC.O.10/100 BTExtension Figure 21 Wireless Extension for Carriers. The same challenges are faced by the CLECs, who will use the AN-50 to quickly; • Extend their existing fiber network, and • Establish a remote Point of Presence (POP). B) Internet Service Providers The AN-50 is perfect for ISPs looking to provide cost effective broadband solutions to demanding business customers including Small Office Home Office (SOHO) and Small to Medium sized Enterprises (SME) located just outside of the downtown core, where there is a lack of infrastructure. High speed leased lines are expensive and hard to obtain, especially from local telephone companies. Wireless access provides a reliable quality of service, over longer distances while avoiding giving away access dollars to the Telco. Internet ISPSMESOHOSME10/100 BT Figure 22 Wireless Solution for ISPs

AN-50 User Manual 39/52 Redline Communications …..solving the first mile challenge. C) Enterprise Enterprises are particularly frustrated by the lack of broadband connectivity to their branch offices, factories, or warehouses located just outside of the urban core. Establishing a LAN solution over several remote locations presents a significant inter-network challenge using conventional wireline solutions. The AN-50 is well suited for addressing the LAN extension requirement, offering superior data rates quickly and efficiently, and in a secure format using Data Encryption Standard (DES) to protect sensitive information. Internet HeadOfficeBranchOfficeFactory10/100 BT Figure 23. Wireless Solution for Enterprise. D) Education and Campuses The World Wide Web (WWW) represents a key element of the education system today, with FWA systems serving as an important enabler in bringing Internet content to the student body. Fixed wireless systems such as the AN-50 provide a cost effective means of creating a backbone for connecting existing and new campus buildings to the educational infrastructure to support distant learning, and two way interactive training. 8.3. The UNII band advantage Wireless systems provide an effective means of achieving broadband connectivity quickly and over large distances. The AN-50 currently operates in the Unlicensed National Information Infrastructure (UNII) band, which is the license exempt (LE) portion of the spectrum. LE bands allow any operator to freely set up a wireless network without requiring formal consent from the regulatory agent. While this provides great advantages in terms of cost effectiveness (e.g. no license fees) and time to market (no regulatory process to follow), the ease of access to the spectrum opens the door for potential interference arising from other operators attempting to exploit the ‘free’ band. The Redline product includes several key features to mitigate the effects of interference arising from other systems

AN-50 User Manual 40/52 Redline Communications …..solving the first mile challenge. operating co-channel in the vicinity, as well as to cope with propagation anomalies such as multipath. These features include: Adaptive Modulation The AN-50 automatically selects modulation level, in both the up and downstream direction (an Industry first), to maximize spectral efficiency based on the measured signal to noise (S/N) level. The modulation levels supported are: • Binary Phase Shift Keying (BPSK) • Quadrature Phase Shift Keying (QPSK) • 16 Qaudrature-Carrier Amplitude Modulation (QAM) • 64 QAM Refer to Table 7 for a summary of data rates for each modulation level. Advanced Error Correction In addition to conventional forward error correction techniques, the AN-50 uses an Acknowledge/Request (ARQ) scheme to dramatically reduce errors from interference and multipath Orthogonal Frequency Division Multiplex (OFDM) processing The Redline OFDM technique offers tremendous robustness in the presence of harsh multipath interference. Narrow Beamwidth Narrow antenna beams reduce considerably the probability of interference entering the system. Adaptive Frequency Tuning In the event the interference is too great, the system will switch over to an alternate ‘clean’ channel. In addition to the anti-interference features described above, the AN-50 also holds several advantages other competitive advantages: • High Data Rates (54) • High Bandwidth Efficiency • Long Reach and Wide Coverage • Higher Power Efficiency • ‘Over the air’ Security

AN-50 User Manual 42/52 Redline Communications …..solving the first mile challenge. The link budget tool estimates the distance over which the system can operate for a desired error rate to achieve robust communication. A link is considered robust if the average error rate is less than 1 bit out of every 1000 million bits, expressed as 10-9, for an availability of 99.99%. Availability is described in more detail below. The table below describes the net data rate (after coding overhead) that can be obtained for each modulation type in an ideal propagation situation. Table 7 Modulation and Data Rate Table. Modulation Level S/Nmin (dB) Coding Rate Symbol Rate (Mbps) Raw Data Rate (Mbps) Net Data Rate (Mbps) BPSK 7 ½ 3 8 6 BPSK 8 ¾ 4.5 12 9 QPSK 11 ½ 6 16 12 QPSK 13 ¾ 9 24 18 16 QAM 16 ½ 12 32 24 16 QAM 20 ¾ 18 48 36 64 QAM 23 ? 24 64 48 64 QAM 25 ¾ 27 72 54 As given in the table, higher order modulation levels require greater S/N to maintain the same BER performance. The noise in this case is defined as the noise floor of the receiver, i.e. it assumes no interference from other sources (interference from other sources are addressed below). The main path calculation for determining range performance is given as: RSL = Ptx + Gtx – FSL + Grx Where: Ptx is the transmit power level in dBm Gtx is the transmit antenna gain in dB FSL is the free space loss attenuation in dB, and Grx is the receive antenna gain in dB The FSL value is dependent on the range between the two terminals, the type of terrain over which the link is deployed, and whether or not the link is operating line of sight (LOS) or non-LOS (NLOS). The LOS FSL calculation is well understood and easy to calculate, and relies on the fact that there is absolutely no obstacle near the direct path. The precise method for determining the amount of clearance required in claiming LOS is to make use of a factor called the Fresnel zone. A Fresnel zone is defined as the path difference of ?/2 away from the direct

AN-50 User Manual 43/52 Redline Communications …..solving the first mile challenge. path, as shown in Figure 24. A ‘cleared LOS’ link assumes there are no obstacles within 60% of the first Fresnel zone of the direct path. FirstFresnelZoneObstruction withinfirst Fresnel Zone Figure 24 Fresnel Zone obstruction. The formula for calculating the radius of the first Fresnel zone, as depicted in Figure 25, is given as: )21(*2*11.72 DDfDDR+= (ft) where, - D1 and D2 are the distances from the terminals to the point of interest (in miles), and - F is the frequency (in GHz) D1D2Fresnel Zone RadiusR Figure 25 Fresnel zone radius calculation. Specific FSL formulas are required to deal with this NLOS phenomenon. There are many NLOS calculations available from established institutions including the Institute of Electrical and Electronics Engineers (IEEE) and International

AN-50 User Manual 44/52 Redline Communications …..solving the first mile challenge. Telecommunications Union (ITU), who are chartered with developing standardized calculations. The Redline link budget tool is built upon these formulas, however, it is important to bear in mind that the calculations are an estimate only, with relatively large standard deviations (5-15 dB) depending on the exact deployment scenario and obstacle characteristics. The last element to consider in the path calculation is the signal to noise (S/N) ratio, which is defined as: S/N = RSL – Smin where, Smin is the receiver sensitivity expressed in dBm. The Smin is determined by the thermal noise generated by the amplifier as well as the bandwidth of the filter used in the receiver front-end. It defines the power level at which the receiver is sensitive enough to properly detect the signal. For the AN-50 operating in a channel spacing of 20 MHz, the Smin is approximately –96 dBm. Therefore, to operate the link at the specified BER, the received signal must exceed Smin by the S/Nmin specified for each modulation level in Table 7. To ensure the link is sufficiently robust to deal with unexpected attenuation effects and seasonal fades, the S/N must be set higher than the S/Nmin specified in Table 7. The difference between these two levels is called the Fade Margin (FM). FM is similar to a ‘power reserve’ in which extra power is designed into the link budget to deal with additional fades arising from such factors as climatic conditions (seasonal), multipath dispersions, and shadowing effects from natural (foliage) and man-made obstacles (buildings). The FM is determined by the availability one desires. Availability is defined as the amount of time (expressed in % per year) that a link properly detects the signal. “Properly” in this case is a BER that is less than 10-9. The table below describes the outage period per year that corresponds to the different availability values. Table 8 Availability versus outage time. Availability (%) Outage Period per year 99.9 8.8 hours 99.99 53 minutes 99.999 5.3 minutes 99.9999 32 seconds The link should be designed for an availability greater than 99.99%. Based on this value, the FM for different ranges is given below: Table 9 Fade margin versus distance for 99.99% availability

AN-50 User Manual 45/52 Redline Communications …..solving the first mile challenge. Distance (km) Fade Margin (dB) 10 5 20 14 30 18 40 23 50 25 The table assumes an average terrain with some roughness and normal inland temperature climate (i.e. non-coastal and non-artic). A key advantage of the Redline product is that it features a transmission correction scheme called Acknowledge/ReQuest (ARQ). The ARQ algorithm essentially detects when a packet(s) has been lost, due to fading, and makes a request to the remote system to re-transmit the lost packet(s). This feature provides an equivalent link budget gain of over 5 dB, which translates directly to an improved margin. Another key advantage of the Redline product is that it features dynamic adaptive modulation, i.e., the system adjusts the modulation level automatically, on a burst-by-burst basis, based on the measured S/N response. In this manner, the network is constantly balanced for the optimum spectral efficiency, no matter what propagation conditions prevail. Higher modulation levels (e.g. 64 QAM) are typically deployed at reduced ranges while lower modulation levels (e.g. BPSK) are implemented at far ranges. A sample link budget is shown in Figure 26 for the AN-50 operating in 16 QAM, 3/4 code rating, providing a net data rate of 36 Megabits per second (Mbps). The tool calculation is performed for LOS, however the graphs below cover the NLOS conditions as well.

AN-50 User Manual 47/52 Redline Communications …..solving the first mile challenge. The graph assumes a fade margin of 15 dB, as discussed earlier. The effects of rain at UNII bands are negligible, hence are not included in the link budget. It is important to note the link calculation assumes that the Earth’s curvature is not blocking the propagation path. The equation for determining the distance at which the Earth will cause blockage is called the Radar Horizon, and is given as follows: Rh=)(1.421 hh + (Km) where, h1 is the height of terminal 1 (m) h2 is the height of terminal 2 (m) The table below specifies the horizon distance (Km) that can be achieved for different terminal heights ranging from 10 to 70 m above mean terrain level. Table 10 Radar horizon ranges for different terminal heights (H1 and H2). H2 10 20 30 40 50 60 70 10 25.9 31.3 35.4 38.9 42.0 44.7 47.3 20 31.3 36.7 40.8 44.3 47.3 50.1 52.6 30 35.4 40.8 44.9 48.4 51.4 54.2 56.8 40 38.9 44.3 48.4 51.9 54.9 57.7 60.2 50 42.0 47.3 51.4 54.9 58.0 60.7 63.3 60 44.7 50.1 54.2 57.7 60.7 63.5 66.1 H170 47.3 52.6 56.8 60.2 63.3 66.1 68.6 8.5. Deployment Scenarios This section examines two types of deployment scenarios: co-located (same roof top) and adjacent area. The current version of the AN-50 is a high-speed point-to-point (PTP) system, supporting a single link (two terminals communicating with each other only). A subsequent software release of the AN-50 will upgrade the system to a Switched-PTP (S-PTP) system. This upgrade will be achieved remotely (i.e. through the internet using the HTTP command set). Hence, it is prudent to design your access network with the knowledge that the system will be upgradeable to a S-PTP unit, to support multiple links from a single node, as shown in Figure 29.

AN-50 User Manual 48/52 Redline Communications …..solving the first mile challenge. T1T2T3 Figure 29 Switched PTP configuration. 8.5.1. Co-located deployments. It is possible to deploy more than one AN-50 from the same roof-top to support multiple links, however, it is important to consider issues that may arise from co-channel and adjacent channel interference. Co-channel interference results when two systems operate simultaneously in the same channel. This must be avoided by programming different channels from the AN-50 Configuration screen. Adjacent channels are acceptable, however, it is important that the adjacent channel does not exceed the acceptable channel to interference (C/I) ratio for the system, as shown in Figure 30 (C is the desired channel, while I is the interferer). Frequency (Mhz)Power (dB) Figure 30 Adjacent channel interference. 8.5.2. Adjacent area deployments. It is important during the installation process to ensure there is no potential for interference from other systems deployed in adjacent areas. Figure 31 presents a simple deployment configuration to illustrate the potential interference that may arise from adjacent area sources (Users 1-4 in the figure). The desired communication link is between Terminals 1 and 2. The link between Users 1 and 2 must operate in an adjacent channel to avoid interference with the desired link. Users 3 and 4, on the other hand, can operate co-channel, since they are outside

AN-50 User Manual 49/52 Redline Communications …..solving the first mile challenge. the narrow beamwidth of both terminals. Narrow beamwidths are one feature of the AN-50 to help address potential interference. Terminal1Terminal2User 4User 3User 1User 2AdjacentChannelCo-Channel Figure 31 Deployment Scenarios.

AN-50 User Manual 50/52 Redline Communications …..solving the first mile challenge. GLOSSARY OF TERMS A/D Analog to Digital AC Alternating Current AN-50 Access Node 50 ARQ Acknowledge Request BER Bit Error Rate Bin Binary BPSK Binary Phase Shift Keying Col Collision DB Decibels DBm Decibels above a milliwatt DHCP Dynamic Host Configuration Protocol FD Dull Duplex FWA Fixed Wireless Access GHz GigaHertz GHz Gigahertz GUI Graphical User Interface HTTP Hyper Text Transfer Protocol IF Intermediate Frequency IP Internet Protocol KB Kilobyte LAN Local Area Network LED Light Emitting Diode LOS Line of Sight MAC Medium Access Control MB Megabyte MHz MegaHertz MHz Megahertz NLOS Non LOS OFDM Orthogonal Frequency Division Multiplex PHY Physical

AN-50 User Manual 51/52 Redline Communications …..solving the first mile challenge. PTP Point to Point QAM Quadrature-Carrier Amplitude Modulation QPSK Quadrature Phase Shift Keying RF Radio Frequency Rx Receiver S/N Signal to Noise ratio S-PTP Switched Point to Point TFTP Trivial File Transfer Protocol Tx Transmitter UNII Unlicensed National Information Infrastructure VAC Voltage AC