Accounting BDS3-BDS2 inter-system biases for precise time transfer
Accounting BDS3-BDS2 inter-system biases for precise time transfer
复制标题
考虑 BDS3-BDS2 系统间偏差以实现精确时间传输
DOI：
10.1016/j.measurement.2020.107566
复制
发表时间：
2020
期刊：
影响因子：
5.6
通讯作者：
Yang Xuhai
中科院分区：
文献类型：
--
作者：
Qin Weijin;Ge Yulong;Zhang Zhe;Su Hang;Wei Pei;Yang Xuhai
BDS的快速发展在带来机遇的同时，也带来了新的问题。本文验证了BDS-2和BDS-3精密单点定位时间传递之间存在偏差。为了区分不同系统中存在的系统间偏差，我们将BDS的内部偏差定义为时延偏差(TDB)。在此基础上，综合分析了具有BDS-2和BDS-3信号能力的所有接收机的TDB特性，并设计了三种TDB随机模型进行参数估计。最后比较了不同的TDB估计策略对时间传递的影响。(1)证实了JAVAD TRE_3、CETC-54-GMR-4016、GNSS GGR和UB4B0-13478接收机中确实存在TDB。在没有外部频率源的情况下，TDB的特性与接收机本身有关。在相同的外部频率源下，两个接收器的TDB趋势呈现出相同的演化。(2)由于时间序列之间的相关性较强，随机游走模型和常量模型估计的时间序列的STD(标准差)和稳定性优于白噪声模型。(3)验证了随机游走模型和常量模型估计的时间传递的稳定性小于白噪声模型的稳定性，并且当双方是不同品牌的接收者时，有TDB估计的钟差和没有TDB估计的钟差存在显著的偏差。当双方是同一品牌的接收机时，有TDB估计的时钟偏差和无TDB估计的时钟偏差存在边际偏差。
The rapid development of BDS not only brings opportunities but also new problems. This article has been verified that the biases exist between BDS-2 and BDS-3 precise point positioning time transfer. We defined internal biases of BDS as Time Delay Bias (TDB) for a distinguish with inter system biases (ISB) exists in different systems. Motivated by the bias, we make comprehensive analysis for determining the characteristics of TDB referring to all the receivers capable of BDS-2 along with BDS-3 signals, furtherly, three kinds of TDB stochastic model are designed for parameter estimation. Later, the influence on time transfer with different TDB estimation strategy is compared in the end. We have some findings: (1) It is confirmed that TDB indeed exists in JAVAD TRE_3, CETC-54-GMR-4016, GNSS GGR and UB4B0-13478 receivers. Without external frequency source, the characteristics of TDB is related to the receiver itself. With the same external frequency source, TDB tendency of two receivers show the same evolution. (2) It is concluded that the STD (Standard Deviation) and stability of TDB estimated with random walk model and constant model is superior to white noise model because of strong correlation among TDB time series. (3) It is verified that the stability of time transfer estimated as random walk model and constant model is smaller than that of white noise model, what is more, when the two sides were receivers of different brands, the significant deviation exists in the clock offset with TDB estimation and without TDB estimation. When the two sides are receiver of the same brand, marginal deviation exists in the clock offset with TDB estimation and without TDB estimation.