FDA-MIMO Radar Moving Target Detection Based on Doppler Spread Compensation

When Frequency Diverse Array and Multiple-Input Multiple-Output (FDA-MIMO) radar detects moving targets, the frequency offset between transmitting arrays is coupled with the target velocity, resulting in severe Doppler spread in the slow time dimension. Further, the signal energy of each receiving channel cannot be coherently accumulated, thereby greatly reducing the detection performance of the system. To address this problem, a method of FDA-MIMO radar moving target detection based on Doppler spread compensation is proposed. Firstly, the moving target echo model of FDA-MIMO radar is established, and the Doppler spread caused by the frequency offset is analyzed. After establishing the maximum likelihood receiver model, a resampling method based on an interpolation filter is proposed to compensate for the Doppler spread caused by FDA-MIMO radar during the detection of moving targets. Simulation results reveal that the proposed method can suppress the Doppler spread, compensate for the cross-cell migration of subtarget echo in the range dimension, and realize the coherent accumulation of signal energy.