Comtech EF Data SNM-1002 - Manual (Page 101)

SNM-1002 LinkSync
 Modem
Revision 2
Theory of Operation MN/SNM1002.OM
4–7
4.3.1 Modulator Specifications
Refer to Table 4-1 for modulator specifications.
Table 4-1. Modulator Specifications
Parameter Specification
Modulation Types BPSK
QPSK
Data Rate Range 2.4 kbit/s to 1.25 Mbit/s 1/2 Rate BPSK
4.8 kbit/s to 2.5 Mbit/s 1/2 Rate QPSK
7.2 kbit/s to 3.75 Mbit/s 3/4 Rate QPSK
8.4 kbit/s to 4.375 Mbit/s 7/8 Rate QPSK
Symbol Rate Range 4.8 ks/s to 2.5 Ms/s
Test Modes Carrier Null and Quadrature (Dual and Offset)
Frequency Range 50 to 180 MHz
Frequency Select Method Synthesized
Frequency Step Size 1 Hz
Frequency Stability
± 10 PPM oscillator
Phase Error 2.5° maximum
Filtering Type Nyquist, pre-equalized
Spectral Occupancy Spectral density is -30 dB at
± 0.75 symbol rate
Spurious and Harmonics -55 dBc, 0 to 500 MHz
Output Power Level Range -5 to -30 dBm,
± 0.5 dB
Output Stability
± 0.5 dB
Output Power Adjustment 0.1 dB step size
Output Impedance 75
Ω
Output Return Loss 20 dB minimum
Scrambler Type INTELSAT V.35
Differential Encoding 2-phase or none
FEC Convolution Encoding/
Viterbi or Sequential Encoding Rate 1/2, 3/4, 7/8
Filter Masks EFD Closed
I/O Connector BNC 75
Ω (TX IF)
Reported Faults AGC Level
IF Synthesizer
I Channel Filter Activity
Q Channel Filter Activity
Modem Reference Activity
Data Clock Syn
Module
Modem Reference PLL