A waveform optimization method for the spatial synthesized phase-coded OFDM signal in MIMO radars

Orthogonal waveforms with good correlation properties are required for target detection in MIMO radar. In this paper, a waveform optimization method for the phase-coded orthogonal frequency division multiplexing (PC-OFDM) signal is proposed. The pulse compression property of the spatial synthesized PC-OFDM signal is firstly analyzed by theoretical derivation. According to the analysis results, the frequency step of PC-OFDM signals is proved to be critical for the high sidelobes. So we optimize the frequency steps of PC-OFDM waveforms by utilizing the sequential quadratic programming (SQP) algorithm to obtain a better sidelobe distribution. Compared with the conventional waveform, the spatial synthesized signals of the optimized waveforms have much better pulse compression properties. Numerical results validate the effectiveness and superiority of the waveform optimization method.