接收机参数对北斗三号卫星伪距偏差影响研究

伪距偏差是抑制北斗系统服务能力提升的重要误差源，影响用户实时定位性能和卫星精密定轨处理.目前对北斗三号伪距偏差的分析研究与测量较少，文章首先从理论上分析了接收机的前端滤波带宽和相关器间隔对伪距偏差的影响，并对理论分析结果进行了仿真.然后在此基础上利用7.5 m大口径天线对北斗三号在轨卫星信号进行采集，使用软件接收机对卫星实测数据的伪距偏差进行测试验证，全面分析了前端滤波带宽和相关器间隔对北斗三号卫星信号伪距偏差的影响.根据理论分析和实测验证的结果，得到了接收机的相关器间隔和前端滤波带宽对北斗三号卫星B1I、B3I和B1C信号的伪距偏差影响范围.研究表明，通过合理设置接收机相关器间隔和前端滤波带宽，可有效减小北斗三号卫星信号伪距偏差，提升用户定位精度.

Influence factors of receiver parameters on the pseudorange biases for BeiDou-3 Navigation Satellite system

Pseudorange bias is an important error source to restrain the improvement of BeiDou Navigation Satellite System(BDS) service capability, which affects users' real-time positioning performance and satellite precise orbit determination. However, there are few researches and measurements on the pseudorange bias of the BDS-3, this paper theoretically analyzes the influence of front-end bandwidth and correlator spacing on pseudorange biases of receivers, and simulates the theoretical analysis results. Then on this basis, the live signals of the BDS-3 was collected with the 7.5 m dish antenna, and the pseudorange biases of the measured data of the live satellite was tested and verified by the software receiver, comprehensively analyzing the influence of front-end bandwidth and correlator spacing on the pseudorange bias of the BDS-3 satellite signal. According to the results of theoretical analysis and test verification, the influence range of front-end bandwidth and correlator spacing of the receiver on the pseudorange bias of the BDS-3 satellite B1I B3I and B1C is obtained. The pseudorange bias of BDS-3 satellite signal can be effectively reduced and the positioning accuracy of users can be improved by setting the suggested parameters.