Comtech EF Data CDM-760 - Demodulator (Dual IF)

Introduction Revision 4
CDM-760 Advanced High-Speed Trunking Modem MN-CDM760
1–11
L-Band Monitor
Port Impedance
Port Connector
Port Level
Port Isolation
Monitor Frequency
50 Ω (available in modulator only or modem configuration)
SMA Female
-27 dBm ± 3dBm
20 dB min
70/140 MHz: 900+70/140 MHz, L-Band: same.
Harmonics and Spurs
< 60 dBc/4kHz, modulated carrier. Excludes spectral mask area.
External Tx Carrier Off
TTL Low signal
Quadrature Phase Error and
Amplitude Imbalance
Sideband 35 dB below unmodulated carrier
Spectral Inversion
Normal or Inverted
Carrier Phase Noise
Frequency Offset
dBc/Hz
Frequency Offset
dBc/Hz
10 Hz
-36
10 kHz
-86
100 Hz
-66
100 kHz
-96
1 kHz
-76
1 MHz
-96
BUC 10 MHz Reference (FUTURE)
Frequency Offset
dBc/Hz
Frequency Offset
dBc/Hz
1.3.6 Demodulator (Dual IF)
70 / 140 MHz
Impedance / Connector
Desired Carrier Input Power
Maximum Composite Level
50 to 180 MHz in 100 Hz steps
75 Ω / BNC Female. Return loss 15 dB min
Min. = -58 +10
log
(SR in Msps) dBm.
Max. = -23 + 10
log
(SR in Msps) dBm, See Figure 1-5
+10 dBm
L-Band
Impedance / Connector
Desired Carrier Input Power
Maximum Composite Level
950-2150 MHz in 100 Hz steps, demodulator
50Ω, Type N Female. Return loss 10 dB min
Min. =
-70 + 10
Log
(SR in Msps) dBm.
Max. =
-20 + 10
Log
(SR in Msps) dBm, See Figure 1-6
+20 dBm
Acquisition Range
For SR < 1Msps, +/- 0.1 * SR, For SR >= 1 Msps, +/- 100 KHz