Optimized transmit beamforming via covariance matrix transformation and combination in colocated MIMO radars

This article presents an efficient approach for the design of waveform covariance matrices in colocated MIMO radars to achieve desired transmit beampatterns. The proposed method, based on Unconstrained Quadratic Programming (UQP), synthesizes a covariance matrix once, and through straightforward transformations and combinations, a variety of single- and multilobe beampatterns can be generated. These transformations are computationally efficient, as they do not require solving the beampattern matching problem repeatedly. The approach ensures that the corresponding covariance matrices adhere to practical constraints while minimizing computational effort. We also demonstrate how this method can be applied to control mainlobe levels and create beampatterns for scenarios where the radar system experiences saturation and level control in the field of view is needed. The proposed method is validated through simulations and numerical result, where it shows superior performance in terms of MSE and computational time compared to existing methods for real-time radar applications.