Operational Features; Operating Modes; Closed Networks; Open Networks (Intelsat) - Comtech EF Data SLM-5650B Installation And Operation Manual

1.3.3

Operational Features

1.3.3.1

Operating Modes

The SLM-5650B supports Closed Network, Open Network and OM-73 modes of operation.
1.3.3.1.1

Closed Networks

Closed Networks refer to private networks with modem operational parameters that do not need
to interoperate with modems developed for commercial open networks (as specified in
accordance with (IAW) Intelsat Earth Station Standards (IESS) -308, IESS-309, and IESS-310
requirements for open network operation).
A Comtech EF Data overhead channel is provided so that the modem is capable of operating in
such closed networks over commercial satellites IAW Intelsat requirements for use during closed
network operation.
1.3.3.1.2

Open Networks (Intelsat)

Open Networks refer to networks that must meet Intelsat specifications for Effective Isotropic
Radiated Power (EIRP), EIRP stability, spurious emissions, intermodulation products, adjacent
carrier interference, frequency tolerance, equalization, and modem parameters such as
modulation, FEC, and scrambling.
The SLM-5650B meets Intelsat certification requirements and is capable of operating in such
open networks over commercial satellites (as specified IAW IESS-308, IESS-309, and IESS-310
requirements for open network operation).
The modem supports the overhead framing integral to those modems, in order to be fully
compatible with commercial modems complying with IESS-308, IESS-309, and IESS-310.
No access is provided to the overhead channel data or alarms.
1.3.3.1.3 OM-73 Mode
The OM-73 Mode allows the SLM-5650B to be compatible with Linkabit's OM-73 modem. This
modem and its operational capabilities have become a de facto standard when operating over
DSCS satellites. All OM-73 modes listed in MIL-STD-188-165A are supported.
Introduction 1–7
SLM-5650B Satellite Modem
Revision 2
MN-SLM-5650B