Automotive MIMO radar system using efficient difference co-array processor

A method for operating a radar system comprising a plurality of transmit and receive antennas and a radar control processing unit, the method comprising:

• transmitting orthogonal MIMO radar signals from transit antennas in the plurality of transmit and receive antennas;
• receiving MIMO radar signal returns from receive antennas in the plurality of transmit and receive antennas;
• processing the MIMO radar signal returns to generate one or more digital signal return output signals;
• constructing, at the radar control processing unit, a sparse MIMO virtual array aperture from the one or more digital signal return output signals;
• and
• constructing, at the radar control processing unit, beamforming outputs of 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.

A radar system comprising:

• a plurality of transmit and receive antennas configured to generate target returns by transmitting MIMO radar signals from transit antennas and receiving MIMO radar signal returns from receive antennas which are processed to generate the target returns;
• and
• a radar control processing unit configured to estimate target parameters by:
• constructing a sparse MIMO virtual array aperture from the one or more digital signal return output signals from the target returns;
• constructing beamforming outputs of 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;
• and
• constructing a target map from the beamforming outputs of the extended difference co-array virtual array aperture to identify the range, Doppler, and angle values for one or more detected targets identified by the target returns.