Joint transmit array interpolation and transmit beamforming for source localization in MIMO radar with arbitrary arrays

We consider a MIMO radar with arbitrary multi-dimensional array, and propose a method for transmit array interpolation that maps an arbitrary transmit array into an array with a certain desired structure. A properly designed interpolation matrix is used to jointly achieve transmit array interpolation and design transmit beamforming. The transmit array interpolation problem is cast as a convex optimization problem based on minmax criterion. Our designs enable to control the side-lobe levels of the transmit beampattern and enforce different transmit beams to have rotational invariance with respect to each other, a property that enables the use of computationally efficient direction finding techniques. It is shown that the rotational invariance can be achieved independently in both the elevation and the azimuth spatial domains, allowing for independent elevation and azimuth direction finding.