Based On Beidou No. 2 / Gps Timing Range Time Unified System Design

Precise coordinate system and time system is the basic premise of shooting range measurement. Shooting range timing system provides shooting range testing facility with uniform precision time, the necessary time mark and the appointed time control signal. At present, most domestic shooting rang uses GPS as the primary timing service, considering the security and reliability of national defense scientific experiment, and DB2(Beidou Navigation Satellite System) achieved the Asian-Pacific region’s passive service at2012, this thesis studied the shooting rang timing system which is based on DB2and GPS dual mode.This thesis expounded the kinds and development of timing service and timing technology, the basic components and key technical index of timing system. Then, the timing service and timing technology principle of GPS, BD1and BD2was researched and analyzed. Combined with the actual project, the hardware and software of the shooting range timing system which is based on BD2/GPS dual-mode and IRIG-B (DC) code as multiple redundant timing source was designed using FPGA technology. Redundant timing mode switch was realized by external switch. Signal integrity distinguish algorithm was used to ensure the validity of receiver module’s output. Local time design also improved the reliability of the equipment. The IRIG-B (DC) encoding and decoding was studied and realized by using Verilog HDL programming. Based on the DLL technology of delay time measurement algorithm, the high precision synchronization of local time and timing sources was realized. The interface section provided three kinds of time information output,1PPS, RS-485and IRIG-B(DC). This timing system’s equipment with a high integrated level, Small volume, Low power consumption, and the precision of the output time signal is better than±1us, has been used in the shooting range testing facility.