Abstract:

In a bistatic airborne radar, since the range-dependence (RD) problem exists in the received ground clutter spectrum, the clutter covariance matrix, which is estimated from the average of the clutter data of each range cell, cannot be accurately estimated, and it makes the clutter suppression performance of space time adaptive processing (STAP) decline. The registration based compensation method compensates the RD problem by sampling along the direction-Doppler curve of the clutter data, but requires heavy computation load due to the large sampling points. Aiming at this problem, the sparse sampling clutter spectrum compensation method is proposed by using the sparse characteristic of the clutter complex amplitude, which is modulated by the transmitter and receiver antennas in the bistatic airborne radar. The proposed method reduces the sampling point number and decreases the computation load of the clutter data reconstruction by setting the sampling threshold. The computer simulation results show that the proposed method can reduce the computation load, mitigate the RD problem of the ground clutter in bistatic airborne radar and thus improve the clutter rejection performance of STAP.