基于冗余量测的GNSS多路径误差抑制算法

针对惯性/卫星组合导航系统中,全球卫星导航系统(global navigation satellite system,GNSS)量测受多径效应影响的问题,提出了一种基于冗余量测的GNSS多径误差抑制方案。该方案包含了一个基于量测新息的GNSS多径误差卡方检验器和一个自适应Kalman滤波器。首先,通过卡方检验来判断量测新息零均值的特性丧失与否以检测GNSS量测中的多径误差。当检测到量测中存在多径误差时,自适应滤波器根据惯性导航系统的冗余量测估计出当前GNSS测量噪声协方差阵,以合理调节量测权重,增强滤波性能。最后,通过仿真与实际跑车试验,验证了该方案能够有效抑制GNSS多径误差,提高了导航精度。

Redundant measurement based method for online mitigation of GNSS multipath errors

A mitigation method for global navigation satellite system (GNSS) multipath errors based on redundant measurement in intertial navigation system (INS)/GNSS integrated system is introduced to solve the problem of the GNSS measurement affected by multipath effects. This method includes an innovation-based chi-square test algorithm and an adaptive Kalman filter. According to the characteristic of the zero mean of the innovation, the chi-square test is used to detect the multipath error in GNSS measurement. When the multipath errors are detected, the adaptive filter can estimate GNSS measurement noise covariance by using the redundant measurement of INS to adjust the weights of measurements, which improves the filtering performance. Finally, the simulation and real test validate that the proposed method can effectively mitigate GNSS multipath errors and improve the accuracy of the navigation solution.