Mitigating Compound Mainlobe Interferences With EPC-MIMO Radar Using Matrix Decomposition

This paper investigates the suppression of mainlobe compound interferences, including the blanket and deceptive interferences with an Element-Pulse Coding-Multiple Input-Multiple output (EPC-MIMO) radar. In specific, by introducing a coding coefficient across the transmit elements and slow-time pulses, the EPC-MIMO radar introduces extra system's Degrees Of Freedoms (DOFs) in the range domain. A ‘low-rank + sparse’ model is established to formulate the received signal via a Joint Space-Time (JST)-Stable Principal Component Pursuit (SPCP)-decomposition framework. To suppress the compound interferences, a Limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS)-based Alternating Optimization (AO) method is employed to extract the mainlobe blanket interferences exploiting the low-rank structure of the signal matrix in the joint space-time domain. Subsequently, a transmit-receive Two-Dimensional (2D) beamformer is designed to suppress mainlobe deceptive interferences with rapid angular variation. Comparative results among different radar frameworks and methodologies are carried out to evaluate the effectiveness of the proposed two-stage interferences suppression method for suppressing compound mainlobe interferences.