Performance and Jamming Test Results of a Digital Beamforming GPS Receiver

Abstract : NAVSYS High Gain Advanced GPS Receiver (HAGR) uses a digital beamsteering antenna array to track up to twelve GPS satellites on L1 and L2, each with up to 10 dBi of additional antenna gain over a conventional receiver solution. This digital, reprogrammable architecture provides a cost effective solution for military applications where precision GPS measurements are needed. The additional gain provided on the satellite signals by the HAGR significantly increases the precision of the observed P(Y) code pseudo-ranges and carrier phase. The HAGR digital beamforming receiver maintains the digital beams directed at each satellite using the receiver's navigation solution, using aiding information from an inertial navigator or attitude reference and the satellite position derived from the ephemeris data. This directivity also improves the Anti-Jamming rejection of the GPS receiver. This paper describes the operation of the HAGR digital beam steering array and presents test results showing the precision navigation capability. Test results from the HAGR at the Electronic Proving Grounds, Fort Huachuca, during jamming tests are also presented that demonstrate the anti-jam performance of a beamsteering receiver.