一种实时GNSS时间传递算法∗

摘要

针对载波相位时间传递算法的局限性,提出了一种实时GNSS(Global Navigation Satellite System)时间传递算法,通过共视(Common View, CV)卫星建立站间非差观测方程的联系,联合解算卫星钟差和站间时间传递结果。该算法不需要卫星精密钟差产品,仅用卫星精密轨道信息直接计算得到站间时间传递结果,不受卫星钟差内插精度、采样率的限制。该算法与通过站间单差将卫星钟差参数进行消除的传统共视算法不同,是将卫星钟差参数进行实时解算得到的。实验结果表明：该算法时间传递精度与传统的GNSS载波相位(Carrier Phase, CP)算法相当,比较适用于实时时间传递。%For the limitations of current algorithms of carrier-phase time transfer, a real-time algorithm of GNSS (Global Navigation Satellite System) time transfer is proposed. Using the relations between un-differenced observation equations which are established through the common view satellite, the results of the satellite clock offset and inter-station time transfer can be calculated at the same time. This method obtains the result of inter-station time transfer only by the satellite ephemeris without using the satellite precise clock products, and it is not limited by the satellite clock error and sampling rate. Different from the traditional common view method in which the parameters of satellite clock offset are eliminated by the single difference, the real-time satellite clock offsets are estimated in this algorithm. Experiment results show that the accuracy of time transfer of the proposed algorithm is the same as that of the GNSS carrier phase algorithm, and this algorithm is more suitable for the real-time time transfer.