Premier Mounts CDM-600 사용자 설명서

다운로드
페이지 250
CDM-600 Satellite Modem 
Revision 7 
Remote Control  
MN/CDM600.IOM 
15–3 
 
-55
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
1.40
1.50
CDM-600 Modulator
typically < -50 dB, and 
guaranteed to be 
< -45 dB at offsets
 > 0.75 Rs
Comtech EF Data
CDM-600 Transmit
 Power Spectral Density, 
referred to symbol rate
Symbol Rate, R
s
Spectral 
density, 
dB
Intelsat
 IESS 308/309 
Limit
Intelsat
 IESS 308/309 
Limit
 
15.2 Demodulator 
Data rate range, operating modes, de-scrambling, input impedance/return loss etc, as per 
Modulator 
 
Input power range 
-30 to -60 dBm (desired carrier) 
 +35 dBC maximum composite, up to -5 dBm 
FEC 
Viterbi: 3 bit soft decision 
Sequential: 2 bit soft decision 
Trellis: Per IESS-310 
Reed-Solomon(Open Network): Per IESS-308/309/310 
Reed-Solomon(Closed Network): Proprietary 
Turbo Product Codec:
 6 bit soft decision, proprietary 
LDPC: 5 bit soft decision, proprietary 
Acquisition range 
±1 to ±32 kHz, programmable in 1kHz increments 
Acquisition time 
Highly dependent on data rate, FEC rate, and demodulator acquisition range. Examples:  200 ms 
average at 64 kbps, R1/2 QPSK, ±32 kHz acquisition sweep range, 6dB Eb/No 
5 s average at 9.6 kbps, R1/2 QPSK, ±10 kHz, 6dB Eb/No 
Note that Reed-Solomon increases acquisition time, due to the additional time taken for the RS 
decoder to declare synchronization. 
Clock tracking range 
± 100 ppm min