Discrete-Phase Sequence Design for Coexistence of MIMO Radar and MIMO Communications

We consider the problem of designing discrete-phase transmit waveform for multiple-input-multiple-output (MIMO) radar to enable its coexistence with MIMO communications. The signal reflected from the target is contaminated with noise, clutter, and interfering communications signal from the base station. We jointly design the radar transmit waveform and its corresponding receive filter in order to maximize the signal-to-interference-plus-noise-ratio with the constant communications rate constraint. In general, this design problem is NP-hard, multi-variable, and non-convex. Contrary to prior works, we tackle this by employing coordinate descent at the waveform design stage. Numerical experiments indicate that the proposed method monotonically increases the signal to noise and interference ratio, while designing discrete phase sequences.