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Demodulator specification summary, A.4 demodulator specification summary, Table a-3. demodulator specification – Comtech EF Data SNM-1001L User Manual

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SNM-1001L Satellite Modem

Revision 1

Specifications

MN/SNM1001L.IOM

A–4

A.4 Demodulator

Specification

Summary

Table A-3. Demodulator Specification

Receive Specifications
Input Connector

Type F Female

Input Impedance

75

Input Return Loss

≥ 10 dB

Minimum Input Level, Desired Carrier

-135 dBm + 10*Log (Symbol Rate), see curve

Input Level AGC

50 dBc, see curve

Input Composite Power:
Symbol Rate

> 64 Ksym/s

<

64

Ksym/s

Absolute maximum

+30 dBc within 10 MHz of desired
+40 dBc with respect to receive signal
+50 dBc with respect to receive signal
-5 dBm

Acquisition Range

± 500 kHz, programmable in 1Hz increments.

BER Performance
(BER vs Eb/N0)

See BER performance tables
Notes: BER specified is for IF loop-back with added noise.

LNB 10 MHz Reference

On center conductor of L-band input connector, selectable
ON/OFF. Level: -3

± 3 dBm.

Source: 1. Internal High Stability Reference
2. REF EXT Supplied at 10 MHz
Performance: For phase noise, refer to L-Band Modulator 10
MHz. Frequency stability is the same as the modulator.

LNB Voltage

On center conductor of L-band input connector, selectable
ON/OFF: 13 and 18 volts per DiSEq 4.2 and 24 VDC at 500
mA, maximum

LNB Current

Programmable MIN and MAX current alarms

LNB Band Control

22kHz tone outbound from L-band connector per DiSEq 4.2.

Test Modes Pattern Monitor

Detects the presence of 2047 data pattern in RX stream and
reports BER.

Monitored Signals

Receive signal level
Raw BER
Corrected BER range 10-3 to 10-12
Eb/N0, 2.0 to 16.0 dB
Rx frequency offset –500 kHz to +500 kHz
Buffer fill status, 1 to 99% in 1% steps