MIMO radar limitations in clutter

Recently discovered bounds for the clear-area available in the ambiguity domain for a MIMO radar waveform set are shown to be a significant limitation in radar applications having extended scatterer distributions. These limitations are demonstrated using an example from an experimental MIMO over-the-horizon radar. Two candidate waveform classes; time-staggered LFMCW, and frequency-staggered LFMCW, are suggested as possible MIMO waveforms in the case of an extended clutter scatterer environment. Each attains the best case bound on reduced clear-area in ambiguity. Limitations discussed in this paper impose significant restrictions to the applicability of MIMO techniques in other clutter-limited applications, such as airborne radar.