GNSS/SINS组合导航中多路径效应的识别与抑制算法

Aiming at the problem that GNSS positioning is easily affected by multipath effect in GNSS/ SINS integrated navigation system, a multipath effect recognition and suppression algorithm is proposed in this paper. The reliability of GNSS output results and the consistency of GNSS/ SINS positioning are detected in real time by designing a two-layer multipath effect recognition method combining attitude detection and X2 inspection. The proposed anti-outlier adaptive filtering algorithm is used to suppress the multipath error. When it is detected that GNSS is affected by multipath effect, the proportion of outlier measurement in measurement update is reduced by residual weighting. When GNSS positioning is normal, the maximum likelihood optimal estimation of residual covariance is calculated by limiting memory index weight, and the fading filter is used to improve the adjustment ability of the filter. The actual vehicle experiments show that the proposed algorithm can effectively suppress GNSS multipath error, and has high navigation accuracy and adaptive ability.