Comtech EF Data SDM-300A - Manual (Page 379)

SDM-300A Satellite Modem Revision 6
Specifications MN/SDM300A.IOM
19–23
19.7 Acquisition Time
Refer to Table 19-20for acquisition time.
Table 19-20. Acquisition Time
Viterbi
6 dB Eb/N0 with ± 35 kHz Frequency Uncertainty
Code Rate Data Rate Tacq P(t < Tacq)
1/2 < 9.6 kbps < 10 sec 95%
1/2 ≥ 9.6 < 64 kbps < 5 sec 95%
1/2 ≥ 64 < 190 kbps < 1 sec 95%
1/2 ≥ 190 < 512 kbps < 10 sec 95%
1/2 ≥ 512 < 1000 kbps < 2.5 sec 95%
1/2 ≥ 1 < 2.5 Mbps < 1 sec 95%
Sequential
6 dB Eb/N0 with ± 35 kHz Frequency Uncertainty
Code Rate Data Rate Tacq P(t < Tacq)
1/2 2.4 < 4.8 kbps < 20 sec 95%
1/2 ≥ 4.8 < 9.6 kbps < 10 sec 95%
1/2 ≥ 9.6 < 64 kbps < 5 sec 95%
1/2 ≥ 64 < 190 kbps < 1 sec 95%
1/2 ≥ 190 < 512 kbps < 17 sec 95%
1/2 ≥ 512 < 1000 kbps < 2.5 sec 95%
1/2 ≥ 1 < 2.5 Mbps < 1 sec 95%
19.7.1 Receive IF Carrier Acquisition Range
The modem locks automatically to a correctly formatted carrier, which is within ± 35 kHz of
the displayed receive frequency. The operator can adjust the following:
Acquisition Range 0 to 70 kHz (in 1 Hz steps)
Center of the Acquisition Range -35 to +35 kHz (in 1 Hz steps)
19.7.2 Receive IF Carrier Reacquisition
The modem is programmed to delay the acquisition process upon loss of lock. This will
miniminize the acquisition time for a brief loss of the carrier. This delay can be programmed
from 0 to 999 seconds in 1-second steps.