Comtech EF Data CDM-710G - Manual (Page 42)

CDM-710G High-Speed Satellite Modem Revision 1
Introduction MN-CDM710G
1–16
1.5.2.2 CDM-710GL L-Band Modulator
Description Requirements
Frequency 950 to 1950 MHz in 100Hz steps. Bandwidth of transmitted spectrum is within IF
frequency range.
Impedance 50 Ω
Connector Type N Male
Return Loss 15 dB
Output Power -5 to -25 dBm in 0.1 dB steps.
Carrier is not interrupted when changing between output power levels or removing
data connections.
Output Power Accuracy ± 0.5 dB at 25°C
Output Power Stability Within ± 0.5 dB of 25C value over all specified environments
Carrier Mute 55 dB below main carrier output
Harmonics and Spurious -55 dBc/4 kHz over operating frequency range (excludes spectral mask area) and is
with a modulated carrier
-55 dBc/4 kHz 250 to 950 MHz, 1950 to 2500 MHz
Integrated Phase Noise Continuous component < 1 degrees RMS double-sided, 100 Hz to 10 MHz
Spectral Inversion Normal or Inverted
Quadrature Phase Error < 2 °
Quadrature Amplitude
Imbalance 0.2 dB maximum
Carrier Null 35 dB below an unmodulated carrier
Combined Amplitude
Imbalance and Quadrature
Phase Error Single sideband test with suppressed sideband 35 dB minimum below unmodulated
carrier
1.5.3 Demodulator
1.5.3.1 CDM-710G 70/140 MHz Demodulator
Description Requirements
Frequency Range 52 to 88 and 104 to 176 MHz in 100 Hz steps
Impedance/Connector 50 Ω or optional 75 Ω/BNC Female
Return Loss 18 dB
Input Power, Minimum -58 + 10xLog(Symbol Rate in MHz) dBm,
-58 dBm at 1 Msps, -41.5 dBm at 45 Msps. See Figure 1-7.
AGC Range 45 dB above minimum
Max Composite Level +20 dBc composite to desired up to +10 dBm
Acquisition Range ± 100 kHz programmable in 1 kHz steps
Acquisition Time Typical < 10 seconds, DVB-S2 Pilots On.
Adaptive Equalizer Up to 3 dB tilt
BER Performance See Table 1-4.
IQ Test Point Accessible from rear panel Alarm connector