Receive Doppler/Plesiochronous Buffer Specifications; Buffer Size; Frame Structures; Buffer Clock Sources - Comtech EF Data SDM-2020 Installation And Operation Manual

Data Interfaces
A.6.5

Receive Doppler/Plesiochronous Buffer Specifications

A.6.5.1

Buffer Size

The operator can set the buffer size, ranging from 2 milliseconds to 32 milliseconds, in
2 millisecond steps. There is also a buffer bypass selection, buffer size of 0 milliseconds.
A.6.5.2

Frame Structures

The unit provides programmable plesiochronous buffer slips.
Frame structures provided according to data rate:
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A.6.5.3

Buffer Clock Sources

The unit shall provide for buffer clock source selections.
Source selections:
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A.6.5.4

Buffer Clock Backup

In the event of failure of the selected buffer clock the unit automatically selects the RX
satellite clock as the backup.
A–50
1544 kbit/s - None or G.704
2048 kbit/s - None or G.704
6312 kbit/s - None, G.704, G.743, or G.747
8448 kbit/s - None, G.704, G.742, or G.745
32064 kbit/s - None or G.752
34368 kbit/s - None, G.751, or G.753
44736 kbit/s - None, G.752
51840 kbit/s - None or STS-1
Internal
Transmit terrestrial
External Reference
RX satellite
SDM-2020 Satellite Demodulator
Rev.3