The Mobile User Objective System

he Navy has used the military UHF band (300–400 MHz) for satellite communications (SATCOM) since the launch of the first Fleet Satellite Communications (FLTSATCOM) satellite in 1978. In the past 30 years, several replacement constellations have been launched, and UHF satellites have become joint assets used by all the services; however, the communication waveforms and architectures have not changed significantly. This article describes a radically new UHF SATCOM system called the Mobile User Objective System (MUOS). MUOS, which is based on the same technology now being widely deployed on terrestrial cellular phone systems, will revolutionize the way that the DoD uses UHF SATCOM. This article describes the MUOS system architecture, APL’s role in the MUOS program, and the impact of our work on other programs at APL.