Compatibility, Description of the modulator, Overview – Comtech EF Data SDM-300L3 User Manual
Page 26: Description
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SDM-300L3 Satellite Modem
Revision 1
Introduction
MN/SDM300L3.IOM
1–6
1.5
Compatibility
The SDM-300L3 is functionally compatible with many Comtech EF Data modems.
When properly configured, the unit will interoperate with the following Comtech EF
Data modems:
•
CDM-550/550T
•
SDM-650B
•
CDM-600/600L
(Open Network and Turbo only)
•
SDM-6000
•
SDM-100/100A
•
SDM-8000
•
SDM-300/300A
1.6
Description of the Modulator
1.6.1
Overview
The modulator provides PSK modulated carriers within the 950 to 1750 MHz range. The
types of modulation that encode the transmitted baseband data from the interface PCB
are:
•
BPSK
•
QPSK
•
OQPSK
•
8-PSK
1.6.2
Description
The modulator is composed of eight basic subsections. These subsections are divided into
the baseband processing section and the RF section of the modulator. The modulator
controls all programmable functions on this module. Fault information from the
modulator is sent to the M&C. Refer to Chapter 9 for a list of reported faults.
The major modulator subsections are:
•
Scrambler/Differential
Encoder
•
Convolutional
Encoder
•
Programmable Vector Rotation
•
I/Q Nyquist Filters
•
Modulator
•
RF
Synthesizer
•
Output
Amplifier
•
Output Level Control