End-to-End Processing Delay, Available TPC Modes | Mocomtech CDM-QX

CDM-Qx Satellite Modem	Revision 5
Forward Error Correction Options	MN/CDMQx.IOM

	Table 6-4. Available TPC Modes

Code Rate/Modulation	Data Rate Range
Rate 21/44 BPSK	32 kbps to 4.772 Mbps
Rate 5/16 BPSK	32 kbps to 3.125 Mbps
Rate 21/44 QPSK	32 kbps to 10 Mbps
Rate 3/4 QPSK	32 kbps to 15 Mbps
Rate 3/4 8-PSK	288 kbps to 20 Mbps
Rate 3/4 16-QAM	384 kbps to 20 Mbps
Rate 7/8 QPSK	32 kbps to 17.5 Mbps
Rate 7/8 8-PSK	336 kbps to 20 Mbps
Rate 7/8 16-QAM	448 kbps to 20 Mbps
Rate 17/18 QPSK	32 kbps to 18.88 Mbps
Rate 17/18 8-PSK	362.7 kbps to 20 Mbps

6.5.3End-to-End Processing Delay

In many cases, FEC methods that provide increased coding gain do so at the expense of increased processing delay. However, with TPC, this increase in delay is very modest. The table below shows, for the Modem, the processing delays for the major FEC types, including the three TPC modes:

Table 6-5. Turbo Product Coding processing delay comparison

FEC Mode (64 kbps data rate)	End-to-end delay, ms

Viterbi, Rate 1/2	12

Viterbi Rate 1/2 + Reed-Solomon	266

Turbo Product Coding, Rate 3/4	47

Turbo Product Coding, Rate 21/44, BPSK	64

Turbo Product Coding, Rate 5/16, BPSK	48

Turbo Product Coding, Rate 7/8	245 *

Turbo Product Coding, Rate 17/18	69

Note that in all cases, the delay is inversely proportional to data rate, so for 128 kbps, the delay values would be half of those shown above. It can be seen that the concatenated Reed-Solomon cases increase the delay significantly (due mainly to interleaving/de- interleaving), while the TPC cases yield delays, which are much less.

*A larger block is used for the Rate 7/8 code, which increases decoding delay.

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Mocomtech CDM-QX End-to-End Processing Delay, Available TPC Modes, Turbo Product Coding processing delay comparison

Contents

Revision CDM-QxPage Acquisition range Errata aPage Errata B Page Rx Rs n/k ENT IESS-310 network 219/201 Errata CPage Tx Rs n/k ENT IESS-310 network 219/201 Errata DPage Part Number MN/CDMQx.IOM Revision January 20,2007 Customer Support Table of Contents Chapter Functional Description External Connections Comparison of all TPC Modes Evolution of TPC in Comtech Products Management Information Base MIB Files 11-1 About this Manual Electrical Safety International Symbols CE Mark Warranty Policy CDM-Qx Satellite Modem Revision Preface MN/CDMQx.IOM Xii CDM-Qx/QxL Introduction Features Software Flash Upgrading DoubleTalk Carrier-in-CarrierVerification Data Interfaces Remote ControlTurbo Product Coding Major Assemblies Assembly Description Fast Fast Options and Hardware Options Hardware Options Fast Accessible OptionsFast System Theory Implementation Supporting Hardware and Software Compatibility Band CDM-Qx Satellite Modem Revision Introduction MN/CDMQx.IOM Unpacking Installation Mounting Optional Rear-Mounting Installation Bracket Installation of the Optional Mounting Brackets Observe the following ConfigurationSelect Internal if Loop Connect External Cables Functional Description Page Modem Block Diagram Page Connections LED Front Panel Rear Panel Rear PanelPage IEC Modem Rear Panel ConnectorsName Ref. Desig Connector Type Function BNC RF Output 75 or 50Ω Use for 2-wire RS-485 operation 2 M&C 10/100BaseT Connector3 485/232 Connector Remote Control Interface Connector Pin Assignments Alarm Interface Connector Pin Assignments Alarms ConnectorPin # Signal Function Name Pin # Signal Function Name Direction Balanced G.703 Connector Tx/Rx ConnectorUnbalanced G.703 Tx/Rx Connectors Balanced G.703 Interface Connector Pin Assignments RS-232 Circuit # 7 RS-530 Data Interface ConnectorPin # Generic Signal Description Direction RS-422 RS Lvds Xx6. Quad E1 Data Interface J1 Connector Pin Assignments Quad E1 Data Interface Connectors AC Power Specifications RX and TX if ConnectorsAC Power Connector DC Power Connector Ground Connector This page is intentionally left blank Operation LED Front Panel LED IndicatorsColor Condition ENT Diamond Keypad Presently used on all UnitsCLR TXF Left-Hand Display AreaModems Right Hand Display Area MD MD Redundancy RXS Accessing the Display AreaSpectrum Analyzer Right-Hand Display Area Principle Menu Tree ODU Main Menu Config Monitor Test Info Save/Load Util ODUOpening Screen Comtech EF Data CDM-Qx Firmware Version Config Remote Tx Rx Group Frame Interface Ref Mask ODU Config Config„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„SNMP Config„Remote„Ethernet„GatewayConfig„Remote„Ethernet„Address Config„Remote„Ethernet„MAC Config„Remote„Ethernet„SNMP„Traps Config„Remote„Ethernet„SNMP„CommunitiesSnmp Trap IP Addr#2 ENT Trap Community , ENT comtechTrap Version ENT SNMPv1 SNMPv2 Trap IP Addr#1 ENT Tx FEC Mod Code Data Freq On/Off Pwr Scram Clk Inv Txα Config„Tx Transmit TPC Config„Tx„FEC TX FEC TypeConfig„Tx„Mod Modulation Scheme Tx FEC Vit Vit+RS TCM+RS Tx Data Rate 05000.000kbps Sym02500.000ksps Config„Tx„Code TX Code RateConfig„Tx„Data TX Data Rate Tx Code Rate 5/16 21/44 1/2 3/4 17/18 Tx if Freq 1156.3456 MHz Config„Tx„Freq TX if Frequency Tx Common Output State Off On Config„Tx„On/Off Transmit ON/OFF ControlTx if Freq 1156.3456 MHz RF=14156.3456 ENT Tx Output State On Off RxTxInhibit Common , ENT Config„Tx„Pwr„Manual Manual Mode Config„Tx„Pwr Transmit Power Level ModeConfig„Tx„Pwr„AUPC Aupc Mode Config„Tx„Pwr„AUPC DEMOD-UNLOCK Config„Tx„Pwr„AUPC Target Eb/NoConfig„Tx„Pwr„AUPC MAX Range Config„Tx„Pwr„AUPC Alarm Config„Tx„Scram Scrambler Config„Tx„Pwr„Combined Combined Transmit PowerConfig„Tx„Clk TX Clocking Mode Tx Data Sense Config„Tx„Inv TX Inversion FunctionsTx Inversion functions Spectrum Data Clock ,ENT Tx Spectral Inversion Normal Inverted RxFEC Demod Code Data Freq Acq Descram Buf Inv Misc CnC Config„Tx„Txα TX Roll-Off α factorConfig„Rx Receive Tx Roll-off 20% 35% ENT Case Rules Comment Config„Rx„FEC RX FEC TypeRx FEC Vit Vit+RS TCM+RS Rx Code Rate 5/16 21/44 1/2 3/4 7/8 17/18 Config„Rx„Demod Demodulation SchemeConfig„Rx„Code RX Code Rate Demodulation Bpsk Qpsk 8-PSK 16-QAM Rx Data Rate 05000.000kbps Sym02500.000ksps Config„Rx„Data RX Data Rate Demod Acquisition Range Config„Rx„Freq RX FrequencyConfig„Rx„Acq Demod Acquisition Range Rx if Freq1156.3456 MHz RF=12156.3456 ENT Config„Rx„Buf RX Buffer Clock Source Config„Rx„Descram DescramblerENT Config„Rx„Misc Rx Miscellaneous Config„Rx„Inv RX Inversion Functions Config„Rx„Misc„Rxα RX Roll-Off α factor Config„Rx„Misc„EbNo Eb/No AlarmConfig„Rx„CnC CARRIER-IN-CARRIER→ Please Wait Config„Rx„CnC„Mode CnC→ Mode of OperationConfig„Rx„CnC„FrqOffs CnC Frequency Offset Please Check TX Power Level Config„Group„Modem Config„Rx„CnC„SrchDelay CnC Search DelayConfig„Rx„CnC„ReAcq CnC RE-ACQUISITION Time Config„Group Grouping MOD/DEMOD Cards Config„Group„Redundancy„Config „12 Config„Group„RedundancyConfig„Group„Redundancy„Config Config„Group„Redundancy„Config „11 Config„Frame„Unframed Unframed Config„Group„Redundancy„ModeConfig„Group„Redundancy„Mode„Manual Config„Frame Framing Mode Master Slave Edmac ModeFraming mix AUPC-Only AUPC+EDMAC Address This Slave Unit ENT Config„Frame„D&I++ D&I++Distant-end Base Address 0240 RTS/CTS operation , ENT Loop,RTS Controls Tx Out Config„Interface Data InterfaceInterface RS422 V.35 RS232 Hssi ASI G.703 QDI None HDB3 AMI 703 E1 Line Code HDB3 AMI , ENT T1 Line Length Feet HDB3 AMI Frequency Reference Internal MHz ENT Config„Ref Reference OscillatorConfig„Mask Mask Alarm Mask Transmit Receive Reference BUC LNB ,ENT AGC Alarm Tx Alarm Mask Tx-FIFO BPV Tx-AIS ENTTx-FIFO Alarm ENT Active Masked Rx Alarm Mask AGC Eb/No Rx-AIS Buffer BUC Alarm Reference AlarmLNB Alarm BUC LNB Config„ODU Outdoor Unit for L-Band Unit OnlyConfig„ODU„BUC Block Upconverter BUC ODU BUC M&C Config„ODU„BUC„M&C-FSK M&C FSKConfig„ODU„BUC„M&C-FSK„Address FSK Comms Config„ODU„BUC„M&C-FSK„Address FSK Address Config„ODU„BUC„Alarm BUC Alarm Config„ODU„BUC„M&C-FSK„Tx-On/Off FSK TX-ON/OFFConfig„ODU„BUC„DC-Pwr BUC DC Power Config„ODU„BUC„10MHz BUC 10MHz Power-On Delay Config„ODU„BUC„Delay BUC DelayBUC Current Alarm Upper Limit1200mA BUC Current Alarm Lower Limit1200mA Config„ODU„BUC„Mix BUC MIX Config„ODU„BUC„LO BUC LO Config„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 Frequency Mix Config„ODU„LNB„LO LOConfig„ODU„LNB„Mix MIX LNB Current Alarm Lower Limit 050mA ENT Monitor„Alarms„Unit Unit Alarms Monitor„Alarms Alarms Monitor„Alarms„Transmit Transmit Alarms Monitor„Alarms„Receive Receive AlarmsMonitor„Alarms„ODU Outdoor Unit Alarms Monitor„Event-Log EVENT-LOG or Stored Events Monitor„Rx-Params RECEIVE-PARAMETERS Monitor„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 Clear all Stored Stats? No Yes Monitor„Stats„Config Configure StatsStats Logging Interval Disabled,ENT Monitor„Stats„Clear-All Clear ALL Stats Monitor„CnC Monitor CARRIER-IN-CARRIER CnC Monitor„AUPC Monitor AUPCfor grouped as modem only ODU LNB Monitor„ODU Monitor ODU for L-Band Unit only Mode 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 Control 10E-3Err=OFF Restart=NO SyncThres=256 Bist BERT-Config BERT-Mon BERT-Control ENTBert Config Tx=ON Rx=ON Tx-Pat=2047 Rx-Pat=2047 Bert Monitor Errs=0000253 BER=8.5E-07 Spectrum Analyzer Mode ConfigSpectrum Analyzer Mode Config Spectrum Analyzer CenterFreq Span If 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 Demod Sweep Acquisition range Info„Rx RX InformationRx 1140.000 05000.000 TUR 8P 17/18 D RX BUF +/-32k N Rx C N N Info„Interface Interface Information Buffer Enabled Tx=Rx ENTInfo„Buffer Buffer Information Info„Frame Framing and Edmac Information Character TST Message Info„Mask Alarm Mask InformationInfo„Ref Frequency Reference Info„ID Circuit Identification No YES Save/Load„Save Save Configuration Contains No Data! ENT Save/Load„Load Load ConfigurationNew Config has been Loaded From Location Empty ENT Real-Time Clock , ,ENT Time=120000 Date24/04/03 Utility„RxBuffer Buffer RecenterUtility„Clock REAL-TIME Clock Utility RxBuffer Clock Ref ID Display Firmware Fast Internal Freq Utility„Ref Reference AdjustWarm-up delay ENT Utility„ID Circuit Identification Utility„Firmware Firmware Utility„Display Display Brightness Update Cpld to v1.x.x? No Yes ENT Current Active Image #1 Next Reboot Image #1 #2Programming Cpld Fast Utility„FAST Fast Code Options Edit 20 digit Fast Code 00000000000000000000 ENT View Options ENT Redun Not Installed Forward Error Correction Options Viterbi Decoding Summary ViterbiFor Against Reed-Solomon Outer Codec Concatenated R-S Coding Summary Closed Network Modes PSK/TCM Coding Summary Trellis Coding Evolution of TPC in Comtech Products Turbo Product Codec Hardware Option Introduction Turbo Product Coding processing delay comparison End-to-End Processing DelayAvailable TPC Modes Comparison of all TPC Modes Turbo Product Coding Summary BER Viterbi Decoding Viterbi with Outer Code PSK/TCM Rate 2/3Decoding, with Without 219, 201 RS Comtech Turbo Product Codec Rate 3/4 QPSK, 8-PSK 16-QAM CDM-Qx Satellite Modem Forward Error Correction Options Comtech Turbo Product Codec Rate 7/8 QPSK, 8-PSK 16-QAM Comtech Turbo Product Codec BPSK/QPSK Rate 21/44 Bpsk and Rate 5/16 Bpsk Turbo BER Page Theory Of Operation Edmac Channel M&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 Ethernet Management Interface Protocols Management Web Web Server Http Interface Web Server Menu Tree Web Server Menu TreeLevel 11-4 11-5 11-6 11-7 Management Information Base MIB Files Snmp Interface Snmp Traps Snmp Community Strings Telnet Interface Alarms and Faults SNMPv2 notifications 11-11 11-12 Page Page FEC Modulator CDM-Qx Transmit Power Spectral DensityReferred to symbol rate Comtech EF Data Turbo Product DemodulatorViterbi PSK/TCM Codec Modulation HIGHER-ORDERCoding Hssi Automatic Uplink Power Control Future Data Rate Ranges Miscellaneous Framing Summary FutureFCC Page Appendix B. Flash Upgrading Ethernet FTP upload procedure Construction Sector CDM-Qx Satellite Modem Revision Flash Upgrading MN/CDMQx.IOM RS-485 Appendix C. Remote Control Basic Protocol RS-232 Example 0135/TRQ=70.2345CR Target-to-controller Packet StructureStart Of Packet Controller-to-target Instruction Code AddressSlot Address ‘=’ code Target to Controller is used in two ways Instruction Code Qualifier $ 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 =QPSK RMD# RMD=RMD= RMD? =BPSK RMD RDR# RDR=RDR= RDR? RDR RSW# RSW=RSW= RSW? RSW EBA# EBA$ EBA=EBA= EBA? EBA ITF# ITF=ITF= ITF? ITF ERF= ESA=ESA= ESA? ESA 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 EID? Query Commands UID? Bytes FLT? =Change in fault REB? WHO? RNE= CC is Fault Code numbers, as in FLT? Or Infor Code, which RNS=CR CDM? RSL?RX BER CRM? 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 BUC LO BLO= BOE=BCH= BCL= BSV? BUCBUT? BPA? Control Band Unit Only Parameter Instruction Type Code Qualifier LNB Power Parameter Instruction Type Code Qualifier Parameter Command Instruction Type Code Qualifier BCT$ BCT=BCT= BCT? BCT# SPM= SPM? SPM=SPF= SPS= DNI= DNI? DNI# DNI$ DNI DNI= DTS= Parameter Instruction Type Code Qualifier Drop TimeslotApplies to Cards grouped As modem CDM-Qx Satellite Modem Revision Remote Control MN/CDMQx.IOM Carrier-in-CarrierDescription Performance Characterization Figure D-1. Adjacent Carrier a As Tested and BAs Plotted Degradation Due To Carrier Spacing Carrier Spacing For 35% Rolloff Carrier Spacing For20% Rolloff Degradation ≤ 0.5 dB PSK 3/4 Turbo, α = 35% Figure D-5. Adjacent Carrier Cases Selecting The Adjacent Carrier Curve Found., or D-4 Curve To Use In Figure D-2, ErrorCarrier-in-Carrier Ratio CnC Ratio Case Desired Adjacent Carrier Figure D-7. CnC Ratio For Qpsk and 8-PSK CnC Carrier Offset Symbol Rate Ratio1st CnC Example Adjacent Carriers, CnC Ratio and Rain Fade Per Figure D DL Fade UL Fade Site a Site BSite a Site B Comment Figure D-10. Link With Fading At Site a 2nd CnC Example CnC Ratio With Asymmetric Links Parameters Site a Site B Link parameters and results are summarized in the table Eb/No Degradation At Site a Parameter Due To Fade At 3rd CnC Example Asymmetric Link With Rain FadePer Figure D- Qpsk Eb/No Degradation At Site B Parameter Due To Fade At Conclusion Metric Conversions 480 333 2200 Phone 480 333 2161 FAX