Test Results from a Digital P(Y) Code Beamsteering GPS Receiver Designed for Carrier-Phase Time Transfer

摘要

The development of time transfer techniques using Global Positioning System (GPS) carrier-phase observations promises the capability to deliver sub- nanosecond time transfer capabilities. NAVSYS' High-gain Advanced GPS Receiver (HAGR) has been designed to enhance the accuracy of the GPS observations by using digital beam-steering from an antenna array. This provides over 10 dB of additional signal gain on each satellite tracked, which improves the accuracy of both the code and carrier tracking loops, simplifying integer ambiguity resolution for carrier-phase time transfer. This same design provides a highly phase stable observation of the GPS carrier, relative to a local reference oscillator, that enables precise time observations to be made for carrier-phase time transfer. In this paper, the design of NAVSYS' P(Y) L1/L2 Code HAGR, developed for precise time transfer applications, is described. Test results are included to show the accuracy of the code and carrier phase observations.