Unimodular Sequence Set Design for MIMO Radar Ambiguity Function Shaping

It has been shown in traditional single antenna radar that designing transmit waveform with an ambiguity function that exhibits low values in specific range-Doppler bins can enhance target detection performance in the clutter from these bins. This letter extends this idea to the case of multiple-input multiple-output (MIMO) radars and deals with the design of a unimodular waveform set with a desired MIMO radar range-Doppler ambiguity function. The phase-coded sequences are generated by minimizing a unified metric that can represent the weighted integrated sidelobe level (WISL) and the peak sidelobe level (PSL) of the local ambiguity function by choosing different parameters. The resulting highly nonlinear optimization problem is solved by the limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) algorithm. Numerical results demonstrate the performance of the proposed method.