Missile tracking with Global Positioning System /GPS/ satellites

The Navstar Global Positioning System (GPS) is a high-precision worldwide network of orbiting navigation satellites. Precise position, velocity, and time are determined by receiving data simultaneously from four satellites and performing some computations. The GPS four-channel navigation receivers are, however, too large, heavy, and expensive for missile installation. A system design has been conceived that incorporates a precision L-band-to-S-band translator (less than 30 cu in) in the missile. The translator's signal is received by a standard telemetry antenna and is then split off to a ground-based GPS receiver. Use of the GPS satellites with a translator on the target has been proved in the Trident I program. The Satellite Tracking system currently in operation provides precision metric data through postflight data analysis.