基于形变模型的空间阵列位置误差估计方法

Position errors estimation for space arrays based on distortion model

大型空间阵列在轨工作时,受热载荷等因素影响发生形变,导致阵元位置误差严重影响雷达系统性能。基于联合迭代的传统阵元位置误差自校正算法没有考虑天线形变特点,在实际应用中精度较差。提出基于形变模型的高精度误差估计算法,在建立天线形变模型的基础上,对每一次迭代估计位置采用总体最小二乘法进行曲面拟合,获得形变模型参数,根据模型参数修正阵元位置估计值,进而逐步迭代得到高精度的角度和位置误差估计。仿真结果验证了该方法的有效性及在低信噪比情况下的稳健性。

The heat load and other factors affect the distortion when large space arrays work on-orbit,resulting in the element position errors which seriously affect the performance of the radar systems.The conventional self-calibration algorithm based on joint iteration ignoring the characteristics of antenna distortion is less accurate in practical application.In this paper,a method of estimation for sensor position errors is proposed.The method calculates the parameter of the distortion model by the overall least squares method for each step.Then the position of the sensor is optimized according to the model parameter.Finally,the high precision angle and position error estimation are repeated through step by step.The simulation results verify the effectiveness of the method and the robustness in the case of low signal-to-noise rate.