Vehicular radar system with self-interference cancellation

A continuous wave, multiple-input, multiple-output (MIMO) radar system for use on vehicle, the MIMO radar system comprising:

• a plurality of receivers coupled to associated receive antennas;
• a plurality of co-located transmitters coupled to associated transmit antennas, and configured to transmit radio signals on a programmable radio carrier frequency modulated with digital symbol sequences;
• a spillover cancellation unit and associated first combiners configured to cancel interference from a signal path of each of the plurality of receivers due to local spillover from the plurality of transmitters;
• wherein for each of the plurality of receivers, the spillover cancellation unit comprises a signal generator configured to produce a cancellation signal for each respective receiver of the plurality of receivers as defined in part by the digital symbol sequences;
• and
• wherein the first combiners are configured to combine each spillover cancellation signal into the received signal path of each intended receiver, wherein the interference from the plurality of transmitters due to the local spillover is removed by subtraction, and wherein combining a spillover cancellation signal into a received signal path subtracts transmitter interference from the signal path.

A method for preventing receivers of a continuous wave multiple-input, multiple-output (MIMO) radar system from being saturated by local spillover from transmitters of the MIMO radar system, the method comprising:

• operating a plurality of receivers of the MIMO radar system during a system calibration phase with only one of a plurality of transmitters of the MIMO radar system operating at a time;
• via monitoring an output signal of each receiver of the plurality of receivers, determining a recipe for each receiver for forming a cancellation signal based on knowledge of a modulation of the only one operating transmitter which, when the cancellation signal is combined with the received signal in the receive path, minimizes a determined output due to the only one operating transmitter;
• via continued monitoring of the output signal of each receiver of the plurality of receivers, determining individual outputs due to each transmitter of the plurality of transmitters as each transmitter is operated in turn as the only operating transmitter to obtain recipes for forming a cancellation signal for each combination of a receiver and a transmitter;
• and
• combining the recipes for all transmitters for a given receiver to form a cancellation signal generation recipe for the given receiver that will cancel the local spillover due to all transmitters at the given receiver when all transmitters are operated at once, and repeating for all receivers to determine a cancellation signal generation recipe for each receiver.