一种高精度的BDS/INS紧耦合测姿算法

针对“北斗”卫星姿态测量系统在测姿过程中测姿精度和稳定性不高的问题，提出了“北斗”卫星导航系统（BDS）/惯性导航系统（INS）紧耦合姿态测量算法。该算法首先利用BDS观测量设计了BDS系统测姿误差模型；然后以INS状态误差方程为滤波系统状态方程，以载波相位为主要观测量设计了扩展卡尔曼滤波器，利用滤波器的输出实现对惯性导航测姿系统的辅助校正；最后采用静态测试、动态测试和遮挡测试验证该算法。该系统可以有效提高BDS测姿精度与输出频率，并且在静态条件下航向角测量精度可以达到0.15°。

A high precision attitude determination algorithm for tightly coupled BDS/INS

For the problem of low accuracy and stability in attitude determination of BeiDou Navigation Satellite System(BDS),this paper proposes a tightly coupled attitude determination algorithm based on BDS and Inertial Navigation System(INS). First,the error model of BDS attitude determination algorithm based on the BDS observation is designed. Then,the extended Kalman filtering(EKF) is designed with the error state equation as the system state equation and the carrier phase as main observation.And the filter output is used to correct the attitude determination of INS.Finally,static tests,dynamic tests and obscured tests are perform to verify the algorithm.The proposed algorithm can dramatically improve the accuracy,stability and output frequency of BDS attitude,and the accuracy of the yaw reaches 0.15°.