Satellite Communications

Article excerpt

The AN/USC-28(V) Satellite Communications Set (Ground) is an advanced spread-spectrum modulation system that operates with defense satellite communications system (DSCS) terminals to provide jam-resistant satellite communication (SATCOM) network control and digital user communications. The AN/USC-28(V) can be configured to accommodate up to 15 user data channels. The equipment interfaces with the digital communications satellite subsystem in fixed terminals and is also installed in the transportable AN/GSC-49(V) terminals. A special airborne version of the AN/USC-28(V) is installed in the super high-frequency terminal aboard the National Airborne Operations Center, the E-4B. The equipment operates with the Navy shipboard OM-55 spread-spectrum equipment. The AN/ USC-28(V), by virtue of the jamming protection it affords, ensures the military utility of the DSCS. The AN/USC-28(V) modem was modified to mitigate the scintillation effects that would be caused by a high-altitude nuclear blast. The modification has backward capability so that the AN/USC-28(V) can operate in the normal mode or in the mitigated mode.

The AN/TSC-85B&C and AN/TSC-93B&C Tactical Satellite Communications Terminals are super high-frequency (SHF) systems that provide reliable multi-channel satellite communications. The C-model terminal contains new modems and converters. All Army terminals are being upgraded to the C -model in 2004. Both terminals operate with an eight-foot-diameter antenna through the defense satellite communications system satellite network. The AN/TSC-85C also uses the 16-foot lightweight high-gain X-band antenna (LHGXA). The AN/TSC-93C provides 24 channels that can operate in a point-to-point mode or as a non-nodal terminal in a nodal network. The AN/TSC-85C provides 48 channels that can also operate in a point-to-point mode or as a nodal terminal in a nodal network. In January 2003, HQDA directed a service life extension program (SLEP) be initiated for all Army TACSAT terminals and subsequently provided OPA funding in FY 2003-06 to upgrade all terminals with new enhanced tactical satellite signal processors (ETSSP); new high-voltage power supplies; new antenna LNA/feed tube; new replacement FM order wire system and a new signal entrance panel and patch panel. …