针对弹载SINS/GPS深组合导航系统提出一种动态检测GPS信号有效性的方法。推导了基于卡尔曼滤波理论和GPS伪距、伪距率量测的SINS/GPS深组合导航算法,通过分析滤波器残差统计特性设计了基于残差X检验的GPS信号故障检测算法和基于切比雪夫大数定理的GPS信号故障隔离算法。理论和仿真分析表明:利用SINS辅助GPS故障检测可进一步提高深组合导航系统的动态抗干扰能力,在GPS单颗或多颗卫星数据出现故障的条件下有效保障组合导航系统的导航精度。

An approach for real-time detecting and isolateing GPS fault in pseudo range and pseudo range rate was presented for tightly integrated missile-borne navigation system composed of SINS and GPS. First, the tightly integration algorithm which takes GPS pseudo range and pseudo range rate directly as measurements was deduced based on SINS navigation error model and Kalman filtering theory. On the basis, a GPS fault detection method based on residual chi-square test and a GPS fault isolation method based on Chebyshev theorem ware designed through analyzing statistical characteristics of the filter residual. Simulation results showed that the proposed algorithm can further improve the system in anti-interference ability and thus guarantee navigation accuracy effectively when-fault occurs to information from one or more satellites occur fault.