噪声协方差自适应控制下的双天线GNSS/INS初始对准方法

为降低系统模型误差及观测模型误差的影响，结合噪声协方差自适应控制机制，对双天线GNSS/INS初始对准方法进行改进。利用噪声协方差自适应控制下的扩展卡尔曼滤波进行数据处理，包括系统噪声协方差控制及观测噪声协方差控制。试验结果表明，系统噪声协方差自适应控制机制可提高系统稳定性，降低滤波稳态值；观测噪声协方差自适应控制机制可降低观测噪声的影响，提高对准绝对精度。采用后处理的方式，利用基线长度偏差最小的基线结果辅助姿态解算，绝对精度进一步提高，对准绝对精度主要受观测值影响。利用本文方法，横滚角、俯仰角对准绝对精度可达0.02°，航向角对准绝对精度可达0.04°。

Two-antenna GNSS Aided-INS Alignment Using Adaptive Control of Filter Noise Covariance

This paper developed a theory of INS fine alignment in order to restrain the divergence of yaw angle,two antennas GNSS aided-INS integrated alignment algorithm was utilized.An attitude error measurement equation was conducted based on the relationship between baseline vectors calculated by two sensors and attitude error.The algorithm was executed by EKF using adaptive control of filter noise covariance.The experimental results showed that stability of the integrated system was improved under the system noise covariance adaptive control mechanism;The measurement noise covariance adaptive control mechanism can reduce the influence of measurement noise and improve the alignment absolute accuracy;Further improvement was achieved under the condition of minimbias of baseline length.The accuracy of roll and pitch was 0.02°,the accuracy of yaw was 0.04°.