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Mocomtech CDM-QX operation manual Symbol Rate Ratio, CnC Carrier Offset

Models: CDM-QX

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

		Eb/No Degradation (vs) CnC Ratio (16-QAM)
	0.0
	-0.2
(dB)	-0.4
(dB)	-0.6
Degradation	-0.6
	-0.8
	-1.0
	-1.2
Eb/No	-1.4	16-QAM 3/4 Turbo
Eb/No	-1.6	16-QAM 7/8 Turbo
	-1.6	16-QAM 7/8 Turbo
	-1.8
	-2.0
	-10	-5	0	5	10
		CnC Ratio (dB)

Figure D-8. CnC Ratio For 16-QAM

D.5	Symbol Rate Ratio

CnC operation is restricted to a maximum symbol rate ratio ≤3. This is the ratio of the larger carrier to the smaller one. Within these limits, the performance characterized applies. The limitation on the symbol range still allows a wide range of data rates.

It is necessary to take into account the symbol rate ratio to properly estimate the CnC ratio, although the modem does this automatically. For estimating the link parameters, the CnC ratio is adjusted by 10 Log (Symbol Rate Ratio). If the symbol rate ratio is 2.0 then the narrower carrier has a 3 dB CnC ratio when the CnC carriers have the same spectral density.

D.6	CnC Carrier Offset

CnC carriers are normally placed directly on top of each other with the same center frequency for both carriers. Normal operation is obtained when the center frequency of the two carriers is within ± 32 kHz. This is the same as the normal acquisition range of the modem for standard and CnC carriers.

D.7	1st CnC Example: Adjacent Carriers, CnC Ratio and Rain Fade

As an example, a pair CnC carriers is flanked by two adjacent CnC pairs with a carrier spacing of 1.3 x Symbol Rate and the power level is the same for all carriers as shown in Figure D-9. In this scenario, the modulation is 8-PSK 3/4 Turbo with identical data rates.

D–8

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Mocomtech CDM-QX Symbol Rate Ratio, CnC Carrier Offset, 1st CnC Example Adjacent Carriers, CnC Ratio and Rain Fade

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 Modes11-1 Management Information Base MIB FilesAbout this Manual Electrical Safety International Symbols CE Mark Warranty Policy CDM-Qx Satellite Modem Revision Preface MN/CDMQx.IOM Xii Introduction CDM-Qx/QxLFeatures Software Flash Upgrading DoubleTalk Carrier-in-CarrierVerification Data Interfaces Remote ControlTurbo Product Coding Assembly Description Major AssembliesFast Options and Hardware Options FastImplementation Fast Accessible OptionsFast System Theory Hardware OptionsSupporting Hardware and Software Band CompatibilityCDM-Qx Satellite Modem Revision Introduction MN/CDMQx.IOM Installation UnpackingOptional Rear-Mounting Installation Bracket MountingInstallation of the Optional Mounting Brackets Connect External Cables ConfigurationSelect Internal if Loop Observe the followingFunctional Description Page Modem Block Diagram Page Connections Front Panel LEDRear Panel Rear PanelPage BNC Modem Rear Panel ConnectorsName Ref. Desig Connector Type Function IECRF 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 operationAlarm Interface Connector Pin Assignments Alarms ConnectorPin # Signal Function Name Balanced G.703 Interface Connector Pin Assignments Balanced G.703 Connector Tx/Rx ConnectorUnbalanced G.703 Tx/Rx Connectors Pin # Signal Function Name DirectionLvds 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 AssignmentsDC Power Connector RX and TX if ConnectorsAC Power Connector AC Power SpecificationsGround Connector This page is intentionally left blank Operation LED Front Panel LED IndicatorsColor Condition ENT Diamond Keypad Presently used on all UnitsCLR Right Hand Display Area Left-Hand Display AreaModems TXFRedundancy MD MDRight-Hand Display Area Accessing the Display AreaSpectrum Analyzer RXSPrinciple Menu Tree Comtech EF Data CDM-Qx Firmware Version Main Menu Config Monitor Test Info Save/Load Util ODUOpening Screen ODUConfig Config Remote Tx Rx Group Frame Interface Ref Mask ODUConfig„Remote„Serial Config„Remote Remote ControlConfig„Remote„Serial„Interface Config„Remote„Serial„Baudrate Config„Remote„Serial„Interface„RS485 RS-485 Bus AddressConfig„Remote„Ethernet Config„Remote„Ethernet„MAC Config„Remote„Ethernet„GatewayConfig„Remote„Ethernet„Address Config„Remote„Ethernet„SNMPConfig„Remote„Ethernet„SNMP„Traps Config„Remote„Ethernet„SNMP„CommunitiesSnmp Trap IP Addr#1 ENT Trap Community , ENT comtechTrap Version ENT SNMPv1 SNMPv2 Trap IP Addr#2 ENTConfig„Tx Transmit Tx FEC Mod Code Data Freq On/Off Pwr Scram Clk Inv TxαTx FEC Vit Vit+RS TCM+RS Config„Tx„FEC TX FEC TypeConfig„Tx„Mod Modulation Scheme TPCTx 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 Sym02500.000kspsConfig„Tx„Freq TX if Frequency Tx if Freq 1156.3456 MHzTx 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 OnConfig„Tx„Pwr„Manual Manual Mode Config„Tx„Pwr Transmit Power Level ModeConfig„Tx„Pwr„AUPC Aupc Mode Config„Tx„Pwr„AUPC Alarm Config„Tx„Pwr„AUPC Target Eb/NoConfig„Tx„Pwr„AUPC MAX Range Config„Tx„Pwr„AUPC DEMOD-UNLOCKConfig„Tx„Scram Scrambler Config„Tx„Pwr„Combined Combined Transmit PowerConfig„Tx„Clk TX Clocking Mode Tx Spectral Inversion Normal Inverted Config„Tx„Inv TX Inversion FunctionsTx Inversion functions Spectrum Data Clock ,ENT Tx Data SenseTx 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 CnCTCM+RS Config„Rx„FEC RX FEC TypeRx FEC Vit Vit+RS Case Rules CommentDemodulation 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 17/18Config„Rx„Data RX Data Rate Rx Data Rate 05000.000kbps Sym02500.000kspsRx if Freq1156.3456 MHz RF=12156.3456 ENT Config„Rx„Freq RX FrequencyConfig„Rx„Acq Demod Acquisition Range Demod Acquisition RangeConfig„Rx„Buf RX Buffer Clock Source Config„Rx„Descram DescramblerENT Config„Rx„Inv RX Inversion Functions Config„Rx„Misc Rx MiscellaneousConfig„Rx„Misc„Rxα RX Roll-Off α factor Config„Rx„Misc„EbNo Eb/No AlarmConfig„Rx„CnC CARRIER-IN-CARRIER→ Please Check TX Power Level Config„Rx„CnC„Mode CnC→ Mode of OperationConfig„Rx„CnC„FrqOffs CnC Frequency Offset Please WaitConfig„Group Grouping MOD/DEMOD Cards Config„Rx„CnC„SrchDelay CnC Search DelayConfig„Rx„CnC„ReAcq CnC RE-ACQUISITION Time Config„Group„ModemConfig„Group„Redundancy„Config „11 Config„Group„RedundancyConfig„Group„Redundancy„Config Config„Group„Redundancy„Config „12Config„Frame Framing Mode Config„Group„Redundancy„ModeConfig„Group„Redundancy„Mode„Manual Config„Frame„Unframed UnframedAUPC+EDMAC Edmac ModeFraming mix AUPC-Only Master Slave0240 Config„Frame„D&I++ D&I++Distant-end Base Address Address This Slave Unit ENTHssi ASI G.703 QDI None Config„Interface Data InterfaceInterface RS422 V.35 RS232 RTS/CTS operation , ENT Loop,RTS Controls Tx OutHDB3 AMI T1 Line Length Feet 703 E1 Line Code HDB3 AMI , ENTHDB3 AMI Alarm Mask Transmit Receive Reference BUC LNB ,ENT Config„Ref Reference OscillatorConfig„Mask Mask Frequency Reference Internal MHz ENTRx Alarm Mask AGC Eb/No Rx-AIS Buffer Tx Alarm Mask Tx-FIFO BPV Tx-AIS ENTTx-FIFO Alarm ENT Active Masked AGC AlarmBUC Alarm Reference AlarmLNB Alarm ODU Config„ODU Outdoor Unit for L-Band Unit OnlyConfig„ODU„BUC Block Upconverter BUC BUC LNBConfig„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&CConfig„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 AlarmBUC Current Alarm Lower Limit1200mA Config„ODU„BUC„Delay BUC DelayBUC Current Alarm Upper Limit1200mA Power-On DelayConfig„ODU„BUC„LO BUC LO Config„ODU„BUC„Mix BUC MIXConfig„ODU„LNB„Voltage LNB Voltage Config„ODU„LNB LNBLNB DC Config„ODU„LNB„10MHz LNB 10MHz Config„ODU„LNB„Power-On/Off LNB POWER- ON/OFFConfig„ODU„LNB„Alarm LNB Alarm LNB Current Alarm Lower Limit 050mA ENT Config„ODU„LNB„LO LOConfig„ODU„LNB„Mix MIX LNB Frequency MixMonitor„Alarms Alarms Monitor„Alarms„Unit Unit AlarmsMonitor„Alarms„Transmit Transmit Alarms Monitor„Alarms„Receive Receive AlarmsMonitor„Alarms„ODU Outdoor Unit Alarms Monitor„Rx-Params RECEIVE-PARAMETERS Monitor„Event-Log EVENT-LOG or Stored EventsMonitor„Event-Log„View View Stored Events Log 023 30/11/02 Fault Demod Lock 3 ,ENTLog 024 30/11/97 Clear Demod Lock 3 ,ENT Monitor„Stats Link Statistics for grouped as modem only Link Statistics View Clear-All Config ENTMonitor„Stats„View View Link Statistics Monitor„Stats„Clear-All Clear ALL Stats Monitor„Stats„Config Configure StatsStats Logging Interval Disabled,ENT Clear all Stored Stats? No YesMonitor„AUPC Monitor AUPCfor grouped as modem only Monitor„CnC Monitor CARRIER-IN-CARRIER CnCMonitor„ODU Monitor ODU for L-Band Unit only ODU LNBMode Norm if 2 Dig 2 I/O 2 RF Tx-CW Tx1-0 ENT Test Mode Bist ENT Spec-AnalyzerTest TX-CW Norm If Loop Dig Loop RF LoopTX-1,0 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=256Config Spectrum Analyzer CenterFreq Span Mode ConfigSpectrum Analyzer Mode Spectrum AnalyzerIf Loopback Info Information Info„Rem Remote Control InformationInfo Rem Tx Rx Buffer Frame Interface Mask Ref ID Tx 1140.000 05000.000 TUR 8P 17/18 S EXT -20.0 on N Info„Tx TX InformationTx C N 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 rangeInfo„Frame Framing and Edmac Information Buffer Enabled Tx=Rx ENTInfo„Buffer Buffer Information Info„Interface Interface InformationInfo„ID Circuit Identification Info„Mask Alarm Mask InformationInfo„Ref Frequency Reference Character TST MessageSave/Load„Save Save Configuration No YESEmpty ENT Save/Load„Load Load ConfigurationNew Config has been Loaded From Location Contains No Data! ENTUtility RxBuffer Clock Ref ID Display Firmware Fast Utility„RxBuffer Buffer RecenterUtility„Clock REAL-TIME Clock Real-Time Clock , ,ENT Time=120000 Date24/04/03Utility„ID Circuit Identification Utility„Ref Reference AdjustWarm-up delay ENT Internal FreqUtility„Display Display Brightness Utility„Firmware FirmwareUpdate Cpld to v1.x.x? No Yes ENT Current Active Image #1 Next Reboot Image #1 #2Programming Cpld Utility„FAST Fast Code Options FastView Options ENT Redun Not Installed Edit 20 digit Fast Code 00000000000000000000 ENTForward Error Correction Options Viterbi Decoding Summary ViterbiFor Against Reed-Solomon Outer Codec Closed Network Modes Concatenated R-S Coding SummaryTrellis Coding PSK/TCM Coding SummaryTurbo Product Codec Hardware Option Introduction Evolution of TPC in Comtech ProductsTurbo Product Coding processing delay comparison End-to-End Processing DelayAvailable TPC Modes Comparison of all TPC Modes Turbo Product Coding Summary Viterbi Decoding BERViterbi with Without 219, 201 RS PSK/TCM Rate 2/3Decoding, with Outer CodeCDM-Qx Satellite Modem Forward Error Correction Options Comtech Turbo Product Codec Rate 3/4 QPSK, 8-PSK 16-QAMComtech 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/QPSKBER Page Edmac Channel Theory Of OperationM&C Connection Setup Summary This page is intentionally left blank Automatic Uplink Power Control Target Eb/No Setting Aupc ParametersMax Range Demod Unlock AlarmCompensation Rate 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 ProtocolsWeb Server Http Interface WebWeb Server Menu Tree Web Server Menu TreeLevel 11-4 11-5 11-6 11-7 Snmp Interface Management Information Base MIB FilesSnmp Community Strings Snmp TrapsAlarms and Faults SNMPv2 notifications Telnet Interface11-11 11-12 Page Page Modulator FECComtech EF Data Power Spectral DensityReferred to symbol rate CDM-Qx TransmitPSK/TCM Codec DemodulatorViterbi Turbo ProductModulation HIGHER-ORDERCoding Automatic Uplink Power Control Future HssiData Rate Ranges Miscellaneous Framing Summary FutureFCC Page Ethernet FTP upload procedure Appendix B. Flash UpgradingConstruction Sector CDM-Qx Satellite Modem Revision Flash Upgrading MN/CDMQx.IOM Appendix C. Remote Control RS-485RS-232 Basic ProtocolController-to-target Packet StructureStart Of Packet Example 0135/TRQ=70.2345CR Target-to-controllerInstruction Code AddressSlot Address Instruction Code Qualifier ‘=’ code Target to Controller is used in two ways$ code target-to-controller is only used as follows Message Arguments Remote CommandsEnd Of Packet 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$ITF ITF=ITF= ITF? ITF#ESA ESA=ESA= ESA? ERF=TST TST=TST= TST? TST#AUP AUP=AUP= AUP? AUP#LBO LBO=LBO= LBO? LBO#HHC? HssiHHC= HHCApplies to CST CST=CST? CST#TIM TIM=TIM= TIM? TIM#IRM IRM=IRM = IRM? IRM#FBU FBU=FBU= FBU? FBU#CSD CSD=CSD? CSD#Query Commands EID?Bytes UID?=Change in fault FLT?WHO? REB?CC is Fault Code numbers, as in FLT? Or Infor Code, which RNE=RNS=CR CRM? RSL?RX BER CDM?SWR? CFM?FRW? IMG IMG=IMG= IMG? IMG#ITP? Bulk Commands OGC OGC=OGC= OGC? OGC#BAD= Arguments For Command or Response to QueryBand Unit Only BCL= BOE=BCH= BUC LO BLO=BPA? BUCBUT? BSV?Parameter Instruction Type Code Qualifier LNB Power Control Band Unit OnlyParameter Instruction Type Code Qualifier Parameter Command Instruction Type Code Qualifier BCT# BCT=BCT= BCT? BCT$SPS= SPM=SPF= SPM= SPM?DNI= DNI= DNI? DNI# DNI$ DNIDTS= Parameter Instruction Type Code Qualifier Drop TimeslotApplies to Cards grouped As modem CDM-Qx Satellite Modem Revision Remote Control MN/CDMQx.IOM Performance Characterization Carrier-in-CarrierDescriptionDegradation Due To Carrier Spacing Figure D-1. Adjacent Carrier a As Tested and BAs PlottedDegradation ≤ 0.5 dB Carrier Spacing For20% Rolloff Carrier Spacing For 35% RolloffPSK 3/4 Turbo, α = 35% Selecting The Adjacent Carrier Curve Figure D-5. Adjacent Carrier CasesCase Desired Adjacent Carrier Curve To Use In Figure D-2, ErrorCarrier-in-Carrier Ratio CnC Ratio Found., or D-4Figure D-7. CnC Ratio For Qpsk and 8-PSK CnC Carrier Offset Symbol Rate Ratio1st CnC Example Adjacent Carriers, CnC Ratio and Rain Fade Comment DL Fade UL Fade Site a Site BSite a Site B Per Figure DFigure 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 BEb/No Degradation At Site a Parameter Due To Fade At 3rd CnC Example Asymmetric Link With Rain FadePer Figure D- Qpsk Conclusion Eb/No Degradation At Site B Parameter Due To Fade AtMetric Conversions 480 333 2200 Phone 480 333 2161 FAX