A radar system, apparatus, architecture, and method are provided for generating a difference co-array virtual aperture by using a radar control processing unit to coherently combine virtual array apertures from multiple small aperture radar devices to construct a sparse MIMO virtual array aperture and to construct an extended difference co-array virtual array aperture that is larger than the MIMO virtual array aperture by using an FFT hardware accelerator to perform spectral-domain auto-correlation based processing of the sparse MIMO virtual array aperture to fill in holes in the sparse MIMO virtual array aperture and to suppress spurious sidelobes caused by holes in the sparse MIMO virtual array aperture.