Notifies the GMF controller of the move time and new terminal location.
Interfaces with technical control of the subscriber.
LEARNING EVENT 12: SYSTEM CONFIGURATION
1. The GMFSCCC is deployed in a number of different system configurations depending on the mission and
theater of operations. The simplest configuration is point-to-point, where the GMF controller monitors over
two TACSAT communications terminals each used as a point. The slightly more complex network is the hub-
spokes configuration. Each low capacity terminal becomes one of the spokes operating with either the
AN/TSC-85B or AN/TSC-100A. The hybrid configuration deals with a number of hub-spoke configurations
with the hubs communicating with each other as well as the spokes in their configuration. A DSCS terminal (a
fixed station satellite communications facility called gateway) can replace a low capacity GMF terminal. In
these configurations, the AN/MSQ-114 has an orderwire control link with all the TACSAT communications
terminals and a monitor link to the satellite. The AN/MSQ-114 can communicate with a DSCS terminal via the
terrestrial critical control circuit (TCCC) network using either an established terrestrial link or a
communications circuit via the satellite. To make DSCS terminals compatible with GMFSC terminals,
additional equipment must be included in the digital communications subsystem (DCSS) of the DSCS terminal.
The GMF contingency rack 20 low rate initial production (LRIP) and GMF contingency rack 20A are single
racks giving limited operational capabilities to the DSCS terminals in the GMF network. To enhance the
capabilities, additional racks are added to produce the DSCS/GMF gateway racks. Included are encryption
devices, antijamming modems, LRSs, and patch panels. The complement of racks is increased to six in this
2. The AN/MSQ-114 terminal consists of an environmentally controlled 34-foot semitrailer, two power
generators, a 20-foot parabolic antenna, prime movers, and a shelter for maintenance and storage of spare parts.
The AN/FSQ-124 consists of four electrical racks, a roll-around cart, and a control console in the facilities of
the host terminal.
3. The AN/MSQ-114 antenna is a 20-foot parabolic antenna type AS-3199/TSC. It has a limited motion of
+10 degrees cross elevation and a full 90 degrees in elevation. Antenna control can be from inside of the van or
remote. The modes of operation provided are manual, acquisition, and auto-track. To acquire a satellite, the
antenna must be implaced with the azimuth look angle very close to the bore sight of the feed system.
a. The receive subsystem consists of redundant antenna mounted low noise amplifiers (LNAs) with 37 to
41 dB gain each and the down-converters. The receive signal is processed from the LNA to a power divider
that provides an eight-way split. Two of the outputs from the divider are dedicated to the SAMS equipment.
Five are connected to five down-converters. The eighth is reserved for future addition of a sixth down-