基于ADS-B的高精度站间同步方法

自动相关监视（ADS-B）可用于多站定位系统中实现时间同步，但直接同步的精度不足以满足工程应用的需要。为了提高同步精度，首先推导了利用ADS-B实现站间同步的机理模型，在实测数据的基础上仿真了直接同步方法的精度水平；其次分析了ADS-B位置误差的类型和来源，得到了不同误差类型的分布特征；最后根据不同误差类型的特点，提出了一种降低ADS-B误差影响的高精度多站同步的方法。该方法可有效降低ADS-B系统延时误差和定位误差对同步精度的影响，以实测数据为基础的仿真结果表明该方法可实现纳秒级的站间同步精度，具有良好的工程应用价值。

A precise synchronization method between receiving stations based on ADS-B

Automatic dependent surveillance-broadcast(ADS-B) can be used to synchronize time between stations,but not enough to meet the needs of engineering application with the accuracy of direct synchronization.For improving the accuracy of time synchronization,mechanism model of time synchronization between stations with ADS-B is derived,and the synchronization accuracy with direct synchronization method based on measured data is simulated.Then,the distribution features of different error types are obtained by analyzing the type and source of ADS-B position error. Finally,a precise time synchronization method with depressing the influence of ADS-B position error is proposed according to the features of different position error types.The proposed method can effectively reduce the influences of ADS-B system delay time error and location error on synchronization accuracy. The simulation result based on measured data shows that the accuracy of time synchronization with this method can reach nanosecond precision,which is of significant engineering application value.