Range-Doppler Spectrum Estimation Based on Matrix Completion for Frequency Agile Radar

Coherent frequency agile (FA) radar has attracted considerable attention. Compared with the stepped frequency radar, FA radar not only has the high range-resolution characteristic obtained by synthesizing large bandwidth, but also has the ability of the range-Doppler decoupling and better electronic countermeasures performance. Typically, traditional matched filter (MF) is often used to estimate the range-Doppler spectrum for FA radar. However, the processing results of the MF method are affected by the raised sidelobe pedestal, which leads to the degradation of radar performance in target detection and parameter estimation. In this paper, we propose a matrix completion (MC)-based method for range-Doppler spectrum estimation. Based on the concept of the FA pattern, the echo is modeled as a time-frequency observation matrix, and we use the MC technique to jointly recover the unobserved data in the matrix to estimate the range-Doppler spectrum with sidelobe pedestal suppression. Moreover, compared with the FA radar with one-dimensional compressed sensing recovery, the MC-based method overcomes the grid mismatch problem, further enhancing the range-Doppler spectrum estimation performance. The simulation results verify the effectiveness of the proposed method.