Wideband MIMO Radar Transmit Beampattern Synthesis in a Spectrally Crowded Environment

The increased electronic equipment makes the spectrum occupied by wireless applications more crowded, seriously weakening the detection performance of the radar. This article addresses the problem of transmit beampattern synthesis for wideband multiple-input multiple-out (MIMO) radar facing the same frequency electromagnetic conflict. According to the prior information about the environment, the spectral constraints are forced on the radar waveform to flexibly control the energy in the specified interference frequency band and direction. Meanwhile, low peak-to-average power ratio (PAR) constraints are added to the radar waveform to achieve high transmission efficiency. To solve this resultant nonconvex multiconstraint beampattern matching design problem, this article proposes an iterative algorithm that simplifies the problem by introducing double auxiliary variables (DAV) and then solves it based on the alternating direction method of multipliers (ADMM) framework. These auxiliary variables allow us to directly control the radar radiation energy at each discrete space-frequency point. In particular, the proposed DAV-ADMM algorithm can guarantee convergence with bounded penalty parameters. Finally, the effectiveness of the algorithm is verified by numerical simulations in various challenging scenarios.