Research On Least Square Estimation For Target Localization In Multistatic System

Least-square (LS) estimation methods of target Localization are frequently used in multistatic radar system, including Linear Least-square method (LLS), Weighted Least-Square method (WLS) and Nonlinear Least-Square method (NonLS).The solution of LS is obtained by minimizing variance of estimation errors. LS methods have advantages of smaller mount of calculation and higher precision of estimation. Two kinds of problems in LLS resulted from location of radar station, rank defect and bad condition number of coefficient matrix are discussed, and an iterative method based on reconstruction of observation equation is designed to solve these problems. For WLS, it is theoretically proved that error covariance matrix is singular when using the same measurements of radar station twice. In order to estimate the position correctly, the error covariance matrix is added a correction to estimate target localization. Finally, two k inds o f i terative m ethods (Gauss-Newton a nd D amp G -S i terative a lgorithm) u tilized i n NonLS are studied, and the simulations show that the latter is more effective and reliable.