Comtech EF Data CDM-425, Инструкция по установке и эксплуатации

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CDM-425 Advanced Satellite Modem
Revision 0
Table of Contents x MN-CDM-425
E.3 Receive Clocking ........................................................................................................................ E–4
E.3.1 Buffer Disabled (RX Satellite) ................................................................................................... E–4
E.3.2 Buffer Enabled, TX=RX (TX Terrestrial or Int (SCT) Clock) ...................................................... E–4
E.3.3 Buffer Enabled, RX<>TX (TX Terrestrial or Int (SCT) Clock) ................................................... E–4
E.4 X.21 Notes .................................................................................................................................... E–6
E.5 Drop and Insert (D&I) .................................................................................................................. E–6
E.6 Frame Formats ............................................................................................................................ E–7
E.7 Timeslot Selection....................................................................................................................... E–8
E.8 Drop and Insert (D&I) Clocking .................................................................................................. E–9
E.9 RX Buffer Clock = Insert (D&I only) .........................................................................................E–10
E.10 Single-Source Multiple Modems ..............................................................................................E–10
E.11 G.703 Clock Extension .............................................................................................................. E–11
E.11.1 Clock Extension Mode 1 ......................................................................................................... E–11
E.11.2 Clock Extension Mode 2 ......................................................................................................... E–12
E.11.3 Clock Extension Mode 3 ......................................................................................................... E–12
E.12 Quad E1 Operation ....................................................................................................................E–17
APPENDIX F. DOUBLE TALK CARRIER-IN-CARRIER (CNC) OPTION ........................................... F–1
F.1 Overview ...................................................................................................................................... F–1
F.1.1 What is DoubleTalk Carrier-in-Carrier? ..................................................................................... F–1
F.1.2 Application Requirements ......................................................................................................... F–2
F.1.3 Operational Recommendations ................................................................................................ F–4
F.2 System Functionality and Operational Considerations .......................................................... F–4
F.2.1 DoubleTalk Carrier-in-Carrier Cancellation Process ................................................................. F–8
F.2.2 Margin Requirements................................................................................................................ F–9
F.2.4 Carrier-in-Carrier and Adaptive Coding and Modulation......................................................... F–10
F.2.5 Carrier-in-Carrier Link Design ................................................................................................. F–10
F.2.5.1 Symmetric Data Rate Link .......................................................................................... F–10
F.2.5.2 Asymmetric Data Rate Link ......................................................................................... F–13
F.2.5.3 Power Limited Links .................................................................................................... F–15
F.2.6 Carrier-in-Carrier Commissioning and Deployment ................................................................ F–17
F.2.7 Validate Carrier-in-Carrier Performance ................................................................................. F–18
F.3 Operational References ............................................................................................................ F–19
F.3.1 Calculate Carrier-in-Carrier Link Budget................................................................................. F–19
F.3.2 Methods to Estimate PSD Ration ........................................................................................... F–20
F.3.2.1 Use Downlink EIRP and Symbol Rate ........................................................................ F–20
F.3.2.2 Use LST ...................................................................................................................... F–20
F.3.2.3 Use Satmaster ............................................................................................................. F–21
F.4 Carrier-in-Carrier Automatic Power Control (CnC-APC) ....................................................... F–22
F.4.1 Overview ................................................................................................................................. F–22
F.4.2 AUPC and Carrier-in-Carrier ................................................................................................... F–22
F.4.3 The CnC Automatic Power Control Algorithm ......................................................................... F–22
F.4.4 CnC-APC Framing .................................................................................................................. F–25
F.4.4.1 CnC-APC Framing and the Self-Locking Problem ...................................................... F–26
F.4.5 CnC-APC Response Time ...................................................................................................... F–26
F.4.6 CnC-APC Setup ...................................................................................................................... F–27
F.4.7 CnC-APC Redundancy Support Notes ................................................................................... F–31
F.5 DoubleTalk Carrier-in-Carrier Specifications ......................................................................... F–32
F.6 Carrier-in-Carrier Summary ...................................................................................................... F–33
F.7 Glossary ..................................................................................................................................... F–33
APPENDIX G. E
B
/N
O
MEASUREMENT ............................................................................................... G–1
G.1 Overview ..................................................................................................................................... G–1
G.1.1 (Co+No)/No Example ............................................................................................................... G–2