Flight test of an integrated digital GPS translator

GPS translators are rugged sensors that relay GPS signals to a ground station for navigational processing. Analog translators have been in use for some time in missile tracking and range safety applications. They suffer, however, from very high cost and require a large bandwidth (>2 MHz) within the air-to-ground telemetry link. This paper describes a recently developed digital translator system with both performance and cost advantages over existing analog translators. The new translator combines the advantages of digital technology with a patented data compression technique to lower the telemetry bandwidth. The ground processing system hardware consists of a PC workstation with a commercial DSP card. Application software, including unique inertial-data aided tracking loops, compute the missile's trajectory. The complete system was tested on a Navy sponsored missile. The process of integrating a generic GPS translator with a missile's antenna and telemetry systems is described. This paper also compares the GPS computed trajectory with radar data.