Research and realization of high-precision GPS time transfer system

This paper presents a high-precision and low-cost time transfer system based on GPS receiver and Field Programmable Gate Array (FPGA). With the aid of the precise one-pulse-per-second (1PPS) signal and the short-term frequency stability of crystal oscillator, this system can obtain high-precision absolute time which is synchronized to Universal Time Coordinated (UTC), by measuring the real-time crystal frequency. A time stamping unit would carry up time information and raw time-domain data into “snapshot” data, and then transmit them to computer for Time-Difference-Of-Arrival (TDOA) analysis. The GPS time transfer system on FPGA has been applied in a radio monitoring receiver.