一种运动双站多脉冲无源定位算法  

A multi-pulse passive localization algorithm for bistatic moving stations

作　　者：周龙健[1] 罗景青[1] 俞志富[1] 吴世龙[1] 

机构地区：[1]解放军电子工程学院,合肥230037

出　　处：《航空学报》2017年第2期244-253,共10页Acta Aeronautica et Astronautica Sinica

基　　金：陕西省自然科学基础研究计划(2013JQ8020)~~

摘　　要：针对运动双站对已知高度的地面目标辐射源高精度定位问题,借鉴SAR成像原理和直接定位法思想,提出了一种利用空中两运动侦察站接收到目标多脉冲信号间的到达时间差(TDOA)和到达频率差(FDOA)信息的无源定位算法。采样时将观测时间分为快时间和慢时间,在快时间域估计时差,慢时间域估计频差,具体方法为:首先将两侦察站的采样信号在频域互相关,然后利用参考函数和广义Keystone变换消除距离单元徙动,再通过二维傅里叶变换得到目标位置点的TDOA和FDOA联合估计值,最后将时差频差联合估计值通过几何关系映射到目标的空间位置。仿真结果表明信噪比较高时逼近直接定位法的克拉美罗下限(CRLB),信噪比较低时仍然可以定位。此外,本文算法不仅计算量小,且适用于不可区分多目标辐射源定位问题,具有高精度和超分辨特性。For accurate localization of wideband signal stationary sources of known height,a novel algorithm is proposed using the information of time difference of arrival（TDOA）and frequency difference of arrival（FDOA）between two moving stations.This method uses the principle of synthetic aperture radar（SAR）imaging and the idea of direct localization for reference.The observing time is divided into fast time and slow time in sampling.TDOA is required in the fast time domain,and FDOA is estimated in the slow time domain.Cross correlation of frequency domain is operated first between the sampling signals of two stations,and range cell migration of signals is then eliminated by reference function and general Keystone transform.The joint TDOA and FDOA are finally estimated by applying 2-D Fourier transform and mapping the position of sources.The results of simulation show that the precision of location is close to Cramer-Rao low bound（CRLB）when SNR is high,and the proposed method can be still used for location in low SNR.Besides,with low computational cost,the proposed algorithm is especially applicable for observing unresolved multiple target localization with properties of high precision and super resolution.

关 键 词：无源定位 合成孔径雷达 直接定位法 频域互相关 广义Keystone变换 

分 类 号：V243.2[航空宇航科学与技术—飞行器设计] TN911.7[电子电信—通信与信息系统]