A Passive Location Method Based on Virtual Time Reversal of Cross Antenna Sensor Array and Tikhonov Regularized TLS

The multi-station direction finding and cross positioning method is often used in three-dimensional passive detection system when the measurement information only has DOA estimation value. However, the essence of this algorithm is to linearize the nonlinear problem, which is very vulnerable to the influence of direction finding error. In order to solve the above problem, the anti-interference virtual time reversal (VTR) algorithm combined with Tikhonov regularization total least squares (TLS) are for passive location. A multi-station passive location model is built and the cross antenna sensor array is used to receive signals. According to the established array model, the coordinate transformation formula of the observation station is derived and the coordinate formula of each array element is obtained by the transformation matrix, then the signal receiving model is established. The coordinates of virtual points are transformed for DOA estimation which accomplished by VTR, then the direction lines obtained. The results of the VTR direction finding are transformed into new space angles and the observation equations of the space angles are constructed. In order to overcome the influence of noise on the positioning solution, Tikhonov regularized TLS method is used to solve the equations for obtaining target position. The simulation results show that the algorithm can achieve high-resolution DOA estimation of the target at low SNR and the positioning errors under different number of observation stations are analyzed. The positioning accuracy has better performance compared with the unimproved least square method.