一种KBR系统相位中心在轨标定算法

摘要

为了保证低低跟踪（SST-LL）重力卫星 K波段微波测距（KBR）系统在轨测距精度，提出了一种KBR系统相位中心在轨标定算法。首先根据卫星姿态机动律设计了一种姿态控制算法，将卫星姿态控制分为喷气机动控制过程和稳定控制过程，然后将卫星稳定控制过程中的KBR、GPS及星敏感器观测数据代入扩展卡尔曼滤波器中估计出 KBR系统相位中心的位置。最后进行了数学仿真验证，结果表明该算法能够对标定过程中的卫星姿态进行稳态控制，姿态稳定控制精度俯仰、偏航优于1 mrad，滚动优于3 mrad；双星KBR相位中心三轴标定精度均控制在1 mm以内，具有良好的稳定精度。%An algorithm for on-orbit calibration of K band ranging (KBR) system phase center of the low-low satellite-to-satellite tracking (SST-LL) gravity satellite was proposed. Firstly, the attitude control algorithm was designed according to the calibration maneuver design, and the satellite control procedure was divided into thruster maneuver control procedure and stabilization control procedure.Secondly,the observation of KBR,GPS and star sensor were used to estimate the phase center of KBR based on extended Kalman filter. The pitch and yaw attitude control error are better than 1 mrad, and the roll error is better than 3 mard which indicates that the calibration attitude stabilization control can be realized. The calibration accuracy of three axises are all better than 1 mm,which verify the fast convergence rate and the steady accuracy of the algorithm.