Parameters Site a Site B | Mocomtech CDM-QX guide

CDM-Qx Satellite Modem	Revision 5
CnCPerformance Characterization	MN/CDMQx.IOM

The link parameters and results are summarized in the table:

Parameters	Site A	Site B
Satellite EIRP (dBW)	37	37
Satellite BOo (dB)	6	6
Satellite BOi (dB)	10	10
Satellite SFD (dbW/m2)	-78	-78
Satellite G/T (dB/K)	0	0

E/S Antenna (meters)	4.5	2.4
Data Rate (kbps)	192	192
Carrier Spacing Factor	1.3	1.3

Conventional Link	8PSK 2/3 TCM	8PSK 2/3 TCM
Occupied BW1 for 2 Carriers (kHz)	274.6	274.6
% of Transponder Power	0.55	0.16

CnC Link	QPSK 3/4 Turbo	QPSK 3/4 Turbo
Occupied BW2 for 2 Carriers (kHz)	166.4	166.4
% of Transponder Power	0.37	0.11
CnC Ratio (dB)	+5.3	-5.3
Expected Eb/No Degradation (dB)	-0.1	0.0

The link asymmetry has increased the CnC ratio at Site A to +5.3 dB. Yet this results in a degradation of only 0.1 dB. This is a C-Band link so no additional change in signal level is expected due to rain fade. The CnC ratio at Site B is -5.3 dB so no degradation is expected.

What is done if the CnC ratio is 10 dB or more? In a C-Band link it is possible to tolerate the additional impairment, but then the modem is operating with less margin. One possibility to reduce the CnC ratio is to increase the amount of power transmitted from the remote site with the smaller antenna. This is feasible in some instances where there are higher power satellite transponders. If the installation is a new one, a larger, though more expensive, antenna is possible at the remote site. This simultaneously decreases the CnC ratio at the hub while increasing it at the remote site.

Another alternative is to reduce the modulation order and/or error correction code rate on the receive side of the remote site. This decreases the power transmitted by the hub and reduces its CnC ratio. The hub’s CnC ratio will decrease further if it is possible to increase the modulation order or code rate at the hub. In the above example changing from QPSK 3/4 to QPSK 1/2 helps reduce the power but requires additional 1.5 times more bandwidth. The 1.2 dB Eb/No difference between rate 3/4 and 1/2 reduces the CnC ratio at the hub.

D–12

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Mocomtech CDM-QX operation manual Link parameters and results are summarized in the table, Parameters Site a Site B

Contents

CDM-Qx RevisionPage Errata a Acquisition rangePage Errata B Page Errata C Rx Rs n/k ENT IESS-310 network 219/201Page Errata D Tx Rs n/k ENT IESS-310 network 219/201Page Part Number MN/CDMQx.IOM Revision January 20,2007 Customer Support Table of Contents Chapter Functional Description External Connections Evolution of TPC in Comtech Products Comparison of all TPC Modes 11-1 Management Information Base MIB Files About this Manual Electrical Safety International Symbols CE Mark Warranty Policy CDM-Qx Satellite Modem Revision Preface MN/CDMQx.IOM Xii Introduction CDM-Qx/QxL Features Verification DoubleTalk Carrier-in-CarrierSoftware Flash Upgrading Turbo Product Coding Remote ControlData Interfaces Assembly Description Major Assemblies Fast Options and Hardware Options Fast Implementation Fast Accessible OptionsFast System Theory Hardware Options Supporting Hardware and Software Band Compatibility CDM-Qx Satellite Modem Revision Introduction MN/CDMQx.IOM Installation Unpacking Optional Rear-Mounting Installation Bracket Mounting Installation of the Optional Mounting Brackets Connect External Cables ConfigurationSelect Internal if Loop Observe the following Functional Description Page Modem Block Diagram Page Connections Front Panel LED Rear Panel Rear PanelPage BNC Modem Rear Panel ConnectorsName Ref. Desig Connector Type Function IEC RF Output 75 or 50Ω Remote Control Interface Connector Pin Assignments 2 M&C 10/100BaseT Connector3 485/232 Connector Use for 2-wire RS-485 operation Pin # Signal Function Name Alarms ConnectorAlarm Interface Connector Pin Assignments Balanced G.703 Interface Connector Pin Assignments Balanced G.703 Connector Tx/Rx ConnectorUnbalanced G.703 Tx/Rx Connectors Pin # Signal Function Name Direction Lvds 7 RS-530 Data Interface ConnectorPin # Generic Signal Description Direction RS-422 RS RS-232 Circuit # Quad E1 Data Interface Connectors Xx6. Quad E1 Data Interface J1 Connector Pin Assignments DC Power Connector RX and TX if ConnectorsAC Power Connector AC Power Specifications Ground Connector This page is intentionally left blank Operation Color Condition Front Panel LED IndicatorsLED CLR Diamond Keypad Presently used on all UnitsENT Right Hand Display Area Left-Hand Display AreaModems TXF Redundancy MD MD Right-Hand Display Area Accessing the Display AreaSpectrum Analyzer RXS Principle Menu Tree Comtech EF Data CDM-Qx Firmware Version Main Menu Config Monitor Test Info Save/Load Util ODUOpening Screen ODU Config Config Remote Tx Rx Group Frame Interface Ref Mask ODU Config„Remote„Serial„Interface Config„Remote Remote ControlConfig„Remote„Serial Config„Remote„Ethernet Config„Remote„Serial„Interface„RS485 RS-485 Bus AddressConfig„Remote„Serial„Baudrate Config„Remote„Ethernet„MAC Config„Remote„Ethernet„GatewayConfig„Remote„Ethernet„Address Config„Remote„Ethernet„SNMP Snmp Config„Remote„Ethernet„SNMP„CommunitiesConfig„Remote„Ethernet„SNMP„Traps Trap IP Addr#1 ENT Trap Community , ENT comtechTrap Version ENT SNMPv1 SNMPv2 Trap IP Addr#2 ENT Config„Tx Transmit Tx FEC Mod Code Data Freq On/Off Pwr Scram Clk Inv Txα Tx FEC Vit Vit+RS TCM+RS Config„Tx„FEC TX FEC TypeConfig„Tx„Mod Modulation Scheme TPC Tx Code Rate 5/16 21/44 1/2 3/4 17/18 Config„Tx„Code TX Code RateConfig„Tx„Data TX Data Rate Tx Data Rate 05000.000kbps Sym02500.000ksps Config„Tx„Freq TX if Frequency Tx if Freq 1156.3456 MHz Tx Output State On Off RxTxInhibit Common , ENT Config„Tx„On/Off Transmit ON/OFF ControlTx if Freq 1156.3456 MHz RF=14156.3456 ENT Tx Common Output State Off On Config„Tx„Pwr„AUPC Aupc Mode Config„Tx„Pwr Transmit Power Level ModeConfig„Tx„Pwr„Manual Manual Mode Config„Tx„Pwr„AUPC Alarm Config„Tx„Pwr„AUPC Target Eb/NoConfig„Tx„Pwr„AUPC MAX Range Config„Tx„Pwr„AUPC DEMOD-UNLOCK Config„Tx„Clk TX Clocking Mode Config„Tx„Pwr„Combined Combined Transmit PowerConfig„Tx„Scram Scrambler Tx Spectral Inversion Normal Inverted Config„Tx„Inv TX Inversion FunctionsTx Inversion functions Spectrum Data Clock ,ENT Tx Data Sense Tx Roll-off 20% 35% ENT Config„Tx„Txα TX Roll-Off α factorConfig„Rx Receive RxFEC Demod Code Data Freq Acq Descram Buf Inv Misc CnC TCM+RS Config„Rx„FEC RX FEC TypeRx FEC Vit Vit+RS Case Rules Comment Demodulation Bpsk Qpsk 8-PSK 16-QAM Config„Rx„Demod Demodulation SchemeConfig„Rx„Code RX Code Rate Rx Code Rate 5/16 21/44 1/2 3/4 7/8 17/18 Config„Rx„Data RX Data Rate Rx Data Rate 05000.000kbps Sym02500.000ksps Rx if Freq1156.3456 MHz RF=12156.3456 ENT Config„Rx„Freq RX FrequencyConfig„Rx„Acq Demod Acquisition Range Demod Acquisition Range ENT Config„Rx„Descram DescramblerConfig„Rx„Buf RX Buffer Clock Source Config„Rx„Inv RX Inversion Functions Config„Rx„Misc Rx Miscellaneous Config„Rx„CnC CARRIER-IN-CARRIER→ Config„Rx„Misc„EbNo Eb/No AlarmConfig„Rx„Misc„Rxα RX Roll-Off α factor Please Check TX Power Level Config„Rx„CnC„Mode CnC→ Mode of OperationConfig„Rx„CnC„FrqOffs CnC Frequency Offset Please Wait Config„Group Grouping MOD/DEMOD Cards Config„Rx„CnC„SrchDelay CnC Search DelayConfig„Rx„CnC„ReAcq CnC RE-ACQUISITION Time Config„Group„Modem Config„Group„Redundancy„Config „11 Config„Group„RedundancyConfig„Group„Redundancy„Config Config„Group„Redundancy„Config „12 Config„Frame Framing Mode Config„Group„Redundancy„ModeConfig„Group„Redundancy„Mode„Manual Config„Frame„Unframed Unframed AUPC+EDMAC Edmac ModeFraming mix AUPC-Only Master Slave 0240 Config„Frame„D&I++ D&I++Distant-end Base Address Address This Slave Unit ENT Hssi ASI G.703 QDI None Config„Interface Data InterfaceInterface RS422 V.35 RS232 RTS/CTS operation , ENT Loop,RTS Controls Tx Out HDB3 AMI T1 Line Length Feet 703 E1 Line Code HDB3 AMI , ENT HDB3 AMI Alarm Mask Transmit Receive Reference BUC LNB ,ENT Config„Ref Reference OscillatorConfig„Mask Mask Frequency Reference Internal MHz ENT Rx Alarm Mask AGC Eb/No Rx-AIS Buffer Tx Alarm Mask Tx-FIFO BPV Tx-AIS ENTTx-FIFO Alarm ENT Active Masked AGC Alarm LNB Alarm Reference AlarmBUC Alarm ODU Config„ODU Outdoor Unit for L-Band Unit OnlyConfig„ODU„BUC Block Upconverter BUC BUC LNB Config„ODU„BUC„M&C-FSK„Address FSK Address Config„ODU„BUC„M&C-FSK M&C FSKConfig„ODU„BUC„M&C-FSK„Address FSK Comms BUC M&C Config„ODU„BUC„10MHz BUC 10MHz Config„ODU„BUC„M&C-FSK„Tx-On/Off FSK TX-ON/OFFConfig„ODU„BUC„DC-Pwr BUC DC Power Config„ODU„BUC„Alarm BUC Alarm BUC Current Alarm Lower Limit1200mA Config„ODU„BUC„Delay BUC DelayBUC Current Alarm Upper Limit1200mA Power-On Delay Config„ODU„BUC„LO BUC LO Config„ODU„BUC„Mix BUC MIX LNB DC Config„ODU„LNB LNBConfig„ODU„LNB„Voltage LNB Voltage Config„ODU„LNB„Alarm LNB Alarm Config„ODU„LNB„Power-On/Off LNB POWER- ON/OFFConfig„ODU„LNB„10MHz LNB 10MHz LNB Current Alarm Lower Limit 050mA ENT Config„ODU„LNB„LO LOConfig„ODU„LNB„Mix MIX LNB Frequency Mix Monitor„Alarms Alarms Monitor„Alarms„Unit Unit Alarms Monitor„Alarms„ODU Outdoor Unit Alarms Monitor„Alarms„Receive Receive AlarmsMonitor„Alarms„Transmit Transmit Alarms Monitor„Rx-Params RECEIVE-PARAMETERS Monitor„Event-Log EVENT-LOG or Stored Events Log 024 30/11/97 Clear Demod Lock 3 ,ENT Log 023 30/11/02 Fault Demod Lock 3 ,ENTMonitor„Event-Log„View View Stored Events Monitor„Stats„View View Link Statistics Link Statistics View Clear-All Config ENTMonitor„Stats Link Statistics for grouped as modem only Monitor„Stats„Clear-All Clear ALL Stats Monitor„Stats„Config Configure StatsStats Logging Interval Disabled,ENT Clear all Stored Stats? No Yes Monitor„AUPC Monitor AUPCfor grouped as modem only Monitor„CnC Monitor CARRIER-IN-CARRIER CnC Monitor„ODU Monitor ODU for L-Band Unit only ODU LNB Test Test Mode Bist ENT Spec-AnalyzerMode Norm if 2 Dig 2 I/O 2 RF Tx-CW Tx1-0 ENT TX-1,0 Norm If Loop Dig Loop RF LoopTX-CW Bert Monitor Errs=0000253 BER=8.5E-07 Bist BERT-Config BERT-Mon BERT-Control ENTBert Config Tx=ON Rx=ON Tx-Pat=2047 Rx-Pat=2047 Bert Control 10E-3Err=OFF Restart=NO SyncThres=256 Config Spectrum Analyzer CenterFreq Span Mode ConfigSpectrum Analyzer Mode Spectrum Analyzer If Loopback Info Rem Tx Rx Buffer Frame Interface Mask Ref ID Info„Rem Remote Control InformationInfo Information Tx C N N Info„Tx TX InformationTx 1140.000 05000.000 TUR 8P 17/18 S EXT -20.0 on N Rx C N N Info„Rx RX InformationRx 1140.000 05000.000 TUR 8P 17/18 D RX BUF +/-32k N Demod Sweep Acquisition range Info„Frame Framing and Edmac Information Buffer Enabled Tx=Rx ENTInfo„Buffer Buffer Information Info„Interface Interface Information Info„ID Circuit Identification Info„Mask Alarm Mask InformationInfo„Ref Frequency Reference Character TST Message Save/Load„Save Save Configuration No YES Empty ENT Save/Load„Load Load ConfigurationNew Config has been Loaded From Location Contains No Data! ENT Utility RxBuffer Clock Ref ID Display Firmware Fast Utility„RxBuffer Buffer RecenterUtility„Clock REAL-TIME Clock Real-Time Clock , ,ENT Time=120000 Date24/04/03 Utility„ID Circuit Identification Utility„Ref Reference AdjustWarm-up delay ENT Internal Freq Utility„Display Display Brightness Utility„Firmware Firmware Programming Cpld Current Active Image #1 Next Reboot Image #1 #2Update Cpld to v1.x.x? No Yes ENT Utility„FAST Fast Code Options Fast View Options ENT Redun Not Installed Edit 20 digit Fast Code 00000000000000000000 ENT Forward Error Correction Options For Against ViterbiViterbi Decoding Summary Reed-Solomon Outer Codec Closed Network Modes Concatenated R-S Coding Summary Trellis Coding PSK/TCM Coding Summary Turbo Product Codec Hardware Option Introduction Evolution of TPC in Comtech Products Available TPC Modes End-to-End Processing DelayTurbo Product Coding processing delay comparison Comparison of all TPC Modes Turbo Product Coding Summary Viterbi Decoding BER Viterbi with Without 219, 201 RS PSK/TCM Rate 2/3Decoding, with Outer Code CDM-Qx Satellite Modem Forward Error Correction Options Comtech Turbo Product Codec Rate 3/4 QPSK, 8-PSK 16-QAM Comtech Turbo Product Codec Rate 7/8 QPSK, 8-PSK 16-QAM Comtech Turbo Product Codec Rate 21/44 Bpsk and Rate 5/16 Bpsk Turbo BPSK/QPSK BER Page Edmac Channel Theory Of Operation M&C Connection Setup Summary This page is intentionally left blank Automatic Uplink Power Control Max Range Setting Aupc ParametersTarget Eb/No Compensation Rate AlarmDemod Unlock Monitoring DoubleTalk Carrier-in-Carrier Page Transponder Utilization with and without CnC→ Page Redundancy CDM-Qx Satellite Modem Revision Redundancy MN/CDMQx.IOM 10-2 Management Ethernet Management Interface Protocols Web Server Http Interface Web Level Web Server Menu TreeWeb Server Menu Tree 11-4 11-5 11-6 11-7 Snmp Interface Management Information Base MIB Files Snmp Community Strings Snmp Traps Alarms and Faults SNMPv2 notifications Telnet Interface 11-11 11-12 Page Page Modulator FEC Comtech EF Data Power Spectral DensityReferred to symbol rate CDM-Qx Transmit PSK/TCM Codec DemodulatorViterbi Turbo Product Coding HIGHER-ORDERModulation Automatic Uplink Power Control Future Hssi Data Rate Ranges FCC Framing Summary FutureMiscellaneous Page Ethernet FTP upload procedure Appendix B. Flash Upgrading Construction Sector CDM-Qx Satellite Modem Revision Flash Upgrading MN/CDMQx.IOM Appendix C. Remote Control RS-485 RS-232 Basic Protocol Controller-to-target Packet StructureStart Of Packet Example 0135/TRQ=70.2345CR Target-to-controller Slot Address AddressInstruction Code Instruction Code Qualifier ‘=’ code Target to Controller is used in two ways $ code target-to-controller is only used as follows End Of Packet Remote CommandsMessage Arguments CDM-Qx Satellite Modem Revision Remote Control MN/CDMQx.IOM TX Remote Commands TCR TCR=TCR? TCR# TSI TSI=TSI= TSI? TSI# TSI$ TCK TCK=TCK= TCK? TCK# RFQ RFQ=RFQ= RFQ? RFQ# RFQ$ =BPSK RMD RMD=RMD= RMD? =QPSK RMD# RDR RDR=RDR= RDR? RDR# RSW RSW=RSW= RSW? RSW# EBA EBA=EBA= EBA? EBA# EBA$ ITF ITF=ITF= ITF? ITF# ESA ESA=ESA= ESA? ERF= TST TST=TST= TST? TST# AUP AUP=AUP= AUP? AUP# LBO LBO=LBO= LBO? LBO# HHC? HssiHHC= HHC Applies to CST CST=CST? CST# TIM TIM=TIM= TIM? TIM# IRM IRM=IRM = IRM? IRM# FBU FBU=FBU= FBU? FBU# CSD CSD=CSD? CSD# Query Commands EID? Bytes UID? =Change in fault FLT? WHO? REB? CC is Fault Code numbers, as in FLT? Or Infor Code, which RNE= RNS=CR CRM? RSL?RX BER CDM? FRW? CFM?SWR? IMG IMG=IMG= IMG? IMG# ITP? Bulk Commands OGC OGC=OGC= OGC? OGC# Band Unit Only Arguments For Command or Response to QueryBAD= BCL= BOE=BCH= BUC LO BLO= BPA? BUCBUT? BSV? Parameter Instruction Type Code Qualifier LNB Power Control Band Unit Only Parameter Instruction Type Code Qualifier Parameter Command Instruction Type Code Qualifier BCT# BCT=BCT= BCT? BCT$ SPS= SPM=SPF= SPM= SPM? DNI= DNI= DNI? DNI# DNI$ DNI Applies to Cards grouped As modem Parameter Instruction Type Code Qualifier Drop TimeslotDTS= CDM-Qx Satellite Modem Revision Remote Control MN/CDMQx.IOM Performance Characterization Carrier-in-CarrierDescription Degradation Due To Carrier Spacing Figure D-1. Adjacent Carrier a As Tested and BAs Plotted Degradation ≤ 0.5 dB Carrier Spacing For20% Rolloff Carrier Spacing For 35% Rolloff PSK 3/4 Turbo, α = 35% Selecting The Adjacent Carrier Curve Figure D-5. Adjacent Carrier Cases Case Desired Adjacent Carrier Curve To Use In Figure D-2, ErrorCarrier-in-Carrier Ratio CnC Ratio Found., or D-4 Figure D-7. CnC Ratio For Qpsk and 8-PSK 1st CnC Example Adjacent Carriers, CnC Ratio and Rain Fade Symbol Rate RatioCnC Carrier Offset Comment DL Fade UL Fade Site a Site BSite a Site B Per Figure D Figure D-10. Link With Fading At Site a 2nd CnC Example CnC Ratio With Asymmetric Links Link parameters and results are summarized in the table Parameters Site a Site B Per Figure D- Qpsk 3rd CnC Example Asymmetric Link With Rain FadeEb/No Degradation At Site a Parameter Due To Fade At Conclusion Eb/No Degradation At Site B Parameter Due To Fade At Metric Conversions 480 333 2200 Phone 480 333 2161 FAX