Receive Input Power (Desired Carrier; Demodulator Channel Spacing/Adjacent Carrier Performance; Figure A-1. Carrier Level Vs Symbol Rate - Comtech EF Data SNM-1001L Installation And Operation Manual

SNM-1001L Satellite Modem
Specifications
A.7.16

Receive Input Power (Desired Carrier)

The modem can meet the specified BER and automatically adjust to a receive input power.
The minimum input signal level is –135 dBm + 10 log (Symbol Rate). E.g. (-98 dBm @
4.8 Ks/s). The maximum desired input signal level is –85 dBm + 10 log (symbol rate).
Monitor accuracy is ± 7.5 dB. See Figure A-1.
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
1
300L_levels.xls
A.7.17

Demodulator Channel Spacing/Adjacent Carrier Performance

The modem BER will be degraded less than 0.5 dB with the following receive signal:
•
•
•
Carrier Level (vs) Symbol Rate
Maximum Level
10
Symbol Rate (Ksym/s)

Figure A-1. Carrier Level vs Symbol Rate

Two like-modulated carriers spaced 1.3 times the symbol rate from the receive
frequency, and/or 1.2 times the acquisition range, whichever is larger.
Each adjacent carrier up to 10 dBc higher in power than the desired carrier.
A single adjacent carrier spaced 1.4 times the symbol rate, up to +20 dBc.
Minimum Level
100 1000
A–18
Revision 1
MN/SNM1001L.IOM
10000