机载SAR惯性导航误差快速估计方法

Fast Inertial Navigation Error Estimation Method for Airborne SAR

为了实现机载SAR图像高精度定位,提出了一种利用子图像BP成像的惯导误差快速估计方法。详细推导了惯导位置和速度误差与BP成像模型定位误差的关系,通过线性近似得到定位误差观测方程,利用最小二乘法得到惯导位置和速度误差的估计。在相同均值和方差的高斯观测噪声下进行蒙特卡罗实验,结果表明该方法与传统距离-多普勒模型估计方法相比具有更小的估计均方误差。

To locate airborne synthetic aperture radar（ SAR） image with high accuracy,a fast inertial navigation error estimation method is proposed by using advantage of sub image back projection（ BP）imaging. The relationship between inertial navigation error in position,velocity and positioning error under BP imaging model is investigated. The observation equation of positioning error is obtained by approximating the relationship in linear. Estimations of inertial navigation error in position and velocity can be obtained by least square method. Monte Carlo tests are processed under Gauss observation errors with the same mean and variance. It is illustrated that the proposed method possesses a lesser error of mean square compared with the conventional range-Doppler（ R-D） model based estimation method.