北斗卫星导航系统B1信号伪距偏差问题研究

Researches on Pseudo-range Biases of BeiDou Navigation Satellite System B1 Signals

目前各大卫星导航系统均存在伪距偏差问题,该现象不但不能通过差分的方式进行抵消,在进行双频电离层误差修正时还会被进一步放大,对卫星导航系统服务精度的提高已构成严重危害。然而目前国内对北斗系统伪距偏差产生机理研究甚少,为了最大程度降低伪距偏差对我国北斗卫星导航系统影响,该文首先深入并详细研究了伪距偏差产生机理及特点,在此基础上设计了试验验证方案,利用国内昊平观测站40 m大口径天线,准确测试并评估了所有北斗卫星导航系统(BDS)在轨可视卫星伪距偏差结果。最后根据试验测试结果,提出针对北斗卫星导航系统的接收机主要参数设置建议,从而能够最大程度上减小伪距偏差问题带来的测距误差和定位误差。该文的研究成果可为GNSS信号设计及实现、GNSS监测评估及用户终端参数设置提供有价值的参考依据。

Due to the distortions of the broadcasted satellite signals and the inconsistencies of parameter settings for different receivers, the single difference or double difference of pseudo-ranges between two receivers are different for two pair of different receivers. Bias inconsistencies will lead to adverse effects for pseudo-rangebased positioning applications. Pseudo-range biases can also hinder carrier-phase ambiguity resolution. However, fewer articles deal with pseudo-range biases for BeiDou navigation satellite System （BDS）. In order to mitigate the impact of biases on BDS to the greatest extent, the generation mechanisms and characteristics of pseudo-range biases are studied in detail firstly. Then based on this, experimental verification methods are designed using Haoping Radio Observatory （HRO） of Chinese Academy of Sciences to observe BDS signals. Pseudo-range biases of all visible BDS satellites are measured and evaluated with high accuracy, using the 40 meters dish antenna and modern equipment of HRO. Finally, some important parameters of BDS receivers, such as the correlator spacing and front-end bandwidth, are suggested to mitigate the ranging errors and positioning errors result from pseudo-range biases. The achievements of this paper can provide a worthy reference for GNSS signal designers, GNSS monitoring and assessment and GNSS receiver designers.