移动卫星通信系统组合姿态估计算法

An Estimation Algorithm with Integrated Attitudes for Mobile Satellite Communication System

针对宽带移动卫星通信系统传感器直接融合姿态估计算法易受外界因素干扰、估算误差难以校正的问题,提出了一种移动卫星通信系统组合姿态估计算法。该算法以移动卫星地球站载体的位置误差、速度误差和姿态误差为系统状态量,建立了9状态的组合导航姿态估计模型;通过使用GPS航向角辅助观测解决了组合姿态估计算法航向角可观性弱、姿态角估计值易发散的问题;通过将转弯判断规则和Sage-Husa自适应控制算法进行融合,降低了GPS航向角测量误差对姿态估计的影响,提高了组合姿态估计算法的精度。实验结果表明:移动卫星通信系统组合姿态估计算法计算简单、实时性好,姿态估计精度优于传感器直接融合算法,其姿态估计误差可控制在±0.5°以内,最小均方误差值小于0.4,满足低成本宽带移动卫星通信波束对准要求。

A low cost attitude estimation algorithm based on the integrated navigation aided with the GPS track angle is proposed to solve the problem that the direct multisensory fusion algorithm of the broad-band mobile satellite communication system is easily affected by the outside factors and estimation errors are difficult to correct.A navigation estimation model with 9 states is built by using the error margin equation including the location,the velocity and the attitude of the low cost inertial sensors as the system equations.A method to use the GPS track angle auxiliary observation is proposed to solve the problem that the yaw of the integrated navigation algorithm is weak and easily divergence.The turn rules and Sage-Husa adaptive control algorithm are proposed to relieve the effects of GPS measurement errors for Attitude estimation,and to improve the accuracy of real-time attitude estimations.Experimental results show that the estimation errors of the algorithm are within ±0.5 °,and is better than estimation error of the algorithm of direct multisensory fusion.The root-mean-square error of attitude estimation values is less than 0.4.It can be concluded that the proposed algorithm meets the requirement of the beam alignment for Mobile Satellite Communications.