基于RAEKF的GPS/INS紧组合导航方法研究

Research on GPS/INS tightly integrated navigation based on RAEKF

针对GPS/INSS组合导航系统对高精度和高可靠性需求不断提升的现状,考虑载体运动复杂性导致运动过程中噪声数学统计特性无法精确确定,且滤波结果易受观测粗差影响的问题,提出一种抗差自适应扩展卡尔曼滤波(Robust Adaptive Extended Kalman Filter,RAEKF)方法。基于惯性导航、卫星导航原理与误差模型确定紧组合工作模式下的卡尔曼滤波数学模型;推导常用EKF模型并构造抗差自适应卡尔曼滤波,通过自适应调整观测值的使用权重提高滤波精度,结果表明抗差自适应滤波能有效抑制粗差对导航结果的影响。

According to the present situation that the high precision and high reliability demand of GPS/INSS integrated navigation system rose,a robust adaptive extended Kalman filter(RAEKF)method was proposed,considering the problem that the mathematical statistical characteristics of noise in motion process were not accurately determined due to the complexity of carrier motion and the filtering results were easy to be affected by the observed coarse difference.Based on inertial navigation,satellite navigation and error model,the mathematical model of Kalman filter under tight combination mode was determined.The EKF model was derived and the adaptive Kalman filter was constructed.The filter precision was improved by adjusting the use weights of the observed value.The results showed that the influence of gross errors on navigation results was effectively suppressed by RAEKF.