| The time synchronization is very important to the distributed system. It is the precondition of data transmission, and the foundation of the distributional system cooperation. Moreover, the high precision time synchronization also has been applied widely in communication, electric power, finance, mapping, national defense and space exploration. But in some specific application, the existing commonly methods cannot achieve the request of the synchronized precision.In this thesis using the bi-directional time-comparing technology establish the high-precision synchronization between base stations in practice. Using wireless way transmits time data, same frequency bi-directional comparing remove the delay of transmission; pseudo-random code capture enhance the capture precision. This plan realize the high precision synchronization between several base station which separated dozens kilometers. Taking satellite as relay, can realize bigger cover time synchronization. The principle is simple, eliminate the time signal transmission delay in traditional time service system; the synchronized precision is high, moreover in synchronized process does not need real-time synchronization, simplify the system design; the design is reliable and feasible, easy to realize. That bas been preliminary finished in VHDL. The major part function module be integrated into one FPGA chip, the auxiliary equipment is few; reduce the environment and the delay between electronic parts affects.At the back of the thesis, proposes an improvement, to increase the operation frequency of the system. Aiming at the time counter's systematic error, ±1 error, the tentative plan abandon the traditional procedure, use mathematics method, phase estimating, to realize time difference measure, and that may eliminate the radicalerror in theory. Although that reduces the system operation frequency, enhance time difference measure precision. This method obtains a good result through simulation.
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