Mocomtech SLM-5650 - Manual (Page 25)

SLM-5650 Satellite Modem Revision 2
Introduction MN/SLM5650.IOM
1–5
1.4 Operating Modes
The modem supports Closed Network, Open Network and OM-73 modes of operation
described as follows.
1.4.1 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 under the IESS-
308, IESS-309, and IESS-310.
The modem, however, is capable of operating in such closed networks over commercial satellites
IAW INTELSAT requirements for closed network operation.
A Comtech EF Data overhead channel is provided for use during Closed Network operation.
1.4.2 Open Networks (INTELSAT)
Open networks refer to networks that must meet INTELSAT specified 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 modem meets INTELSAT certification requirements and is capable of operating in such
open networks over commercial satellites IAW IESS-308, IESS-309, and IESS-310 requirements
for open network operation.
In order to be fully compatible with commercial modems complying with IESS-308, IESS-309,
and IESS-310, the modem supports the overhead framing integral to those modems. It is
important to note that no access to the overhead channel data or alarms is provided.
1.4.3 OM-73
OM-73 mode allows the SLM-5650 to be compatible with Linkabit’s original OM-73 modem.
This modem and it’s operational capabilities have become a defacto standard when operating
over DSCS satellites. All OM-73 modes listed in MIL-STD-188-165A are supported.
1.5 Data Interfaces
The SLM-5650 supports two native data interfaces as well as a option slot for an additional
modular data interface. The two native interfaces are TIA/EIA-530/422 and TIA/EIA-613
(HSSI). The option interface available at this time is the Gigabit Ethernet. The modem will
currently support only one interface at a time.