Comtech EF Data SLM-5650A Installation And Operation Manual page 288

B.3.2 IDR/IBS G.703 Master/Slave
Use this application when the far end earth station does not have local access to a high stability
reference clock, or when it is not required to synchronize with a local clock. Refer to Figure B-2
for:
•
Clocking block diagram
•
TX clock options
•
Buffer clock options for using external loop timing
Modem loop timing does not apply for G.703 operation. The terrestrial equipment must select
loop timing to recover the clock off the RX data and use that recovered clock for the TX data.
The disadvantage of the master/slave application is that the signal received at the slave station is
subject to Doppler shift. The length of the buffer at the master end will need to be twice the length
that is normally required, compensating for the Doppler shift on the outward and return paths
Appendix B B–18
SLM-5650A Satellite Modem
Revision 10
MN-SLM-5650A