Comtech EF Data CDM-740 - Manual (Page 34)

CDM-740 Advanced Satellite Modem Revision 0
Introduction MN-CDM740
1–10
1.5 Summary of Specifications
1.5.1 Transmit / Modulator
Modulation QPSK, 8-QAM and 16-QAM
Symbol Rate Range 4.8 ksps to 3.00 Msps, programmable in 1 sps steps
Data Rate Range 16 kbps to 9.980 Mbps, programmable in 1 bps steps
Operating
Frequency Range
70/140 MHz 50 to 180 MHz IF, 100 Hz frequency resolution
L-Band 950 to 2150 MHz L-Band, 100 Hz frequency resolution
Frequency
Stability
70/140 MHz ±0.06 ppm, 0º to 50ºC (32º to 122ºF)
L-Band
±0.06 ppm, 0º to 50ºC (32º to 122ºF)
Output Power
70/140 MHz -5 to -25 dBm, 0.1 dB steps
L-Band -5 to -40 dBm, 0.1 dB steps
Power Accuracy
70/140 MHz ± 1.0 dB over frequency and temperature
L-Band ± 1.0 dB at 25 C over frequency and temperature
Tx Monitor Port
Selectable
On/Off
Output is L-Band.
Monitor 70/140 900 MHz + IF carrier frequency
Monitor L-Band Same as L-Band frequency
Level -45 dBm typical
Mute Mutes when Tx carrier is muted
Phase Noise
70/140 MHz < 1 degree RMS double-sided, 100 Hz to 1 MHz
L-Band < 1 degrees RMS double-sided,100 Hz to 1 MHz
FEC Turbo Product Codec (TPC): 6 bit soft decision, proprietary
Operating Modes TPC:
•
Rate 21/44 QPSK
•
Rate 3/4 QPSK
•
Rate 7/8 QPSK
•
Rate 0.95 QPSK
• Rate 3/4 8-QAM
• Rate 7/8 8-QAM
• Rate 0.95 8-QAM
•
Rate 3/4 16-QAM
•
Rate 7/8 16-QAM
Note: Refer to Table 5-1 for additional data rate/symbol rate information.
Transmit Filtering IESS-308/-309 spectral mask
Scrambling Comtech, IESS-315 per ITU V.35 (Intelsat variant), disabled
External Reference In/Out See Sect. 1.5.3 Data Interfaces
Harmonics and Spurious < -60 dBc/4 kHz over operating frequency range (Typically < -65 dBc/4 kHz)
BUC Reference (10 MHz) Via Tx IF center conductor, 10 MHz per reference, selectable ON/OFF, 0 dBm
±3 dB