On-demand multi-scan micro doppler for vehicle

A method for achieving high resolution Doppler measurements for a vehicle radar sensing system, the method comprising:

• providing a radar sensing system comprising (i) a transmit pipeline configured for installation and use on a vehicle, wherein the transmit pipeline comprises a plurality of transmitters configured to transmit radio signals, (ii) a receive pipeline configured for installation and use on the vehicle, wherein the receive pipeline comprises a plurality of receivers configured to receive radio signals that include the transmitted radio signals reflected from objects in the environment, and (iii) a processor for processing the radio signals received by the plurality of receivers;
• sampling the received radio signals during a first plurality of time slices of a first scan, wherein each time slice comprises a plurality of samples, a respective sample for each range bin of each plurality of range bins for each receiver of the plurality of receivers in each time slice, and wherein the samples are produced by correlating the received signals to time-delayed replicas of the transmitted signals;
• accumulating the first plurality of time slices into a first radar data cube during the first scan;
• sampling the received radio signals during a second plurality of time slices of a second scan;
• accumulating the second plurality of time slices into a second radar data cube during the second scan;
• outputting the first and second radar data cubes to the processor;
• with the processor, selectively Doppler processing a portion of the first radar data cube, producing a first partial Doppler output, discarding the first radar data cube, and saving the first partial Doppler output into a memory;
• wherein the portion of the first radar data cube comprises a first time series of samples for at least one range bin of each receiver of the plurality of receivers;
• with the processor, selectively Doppler processing a second time series of samples from the second radar data cube to produce a second partial Doppler output;
• and
• with the processor, storing the second partial Doppler output into the memory by numerically accumulating the second partial Doppler output with the first partial Doppler output.

A radar sensing system for a vehicle, the radar sensing system comprising:

• a transmit pipeline configured for installation and use on a vehicle, wherein the transmit pipeline comprises a plurality of transmitters configured to transmit radio signals;
• a receive pipeline configured for installation and use on the vehicle, wherein the receive pipeline comprises a plurality of receivers configured to receive radio signals that include the transmitted radio signals reflected from objects in the environment;
• and
• a processor;
• wherein the receive pipeline is configured to correlate received radio signals of the plurality of receivers with a plurality of time-delayed replicas of the transmitted radio signals to produce samples;
• wherein each time-delayed replica of the plurality of time-delayed replicas of the transmitted radio signals corresponds with a particular range bin of a particular receiver of the plurality of receivers;
• wherein samples are produced during at least two or more scans, each scan comprising a respective plurality of time slices;
• wherein each time slice of the respective plurality of time slices comprises a two-dimensional array of samples, the two-dimensional array defined by the plurality of receivers and a respective plurality of range bins for each receiver of the plurality of receivers;
• wherein each range bin of each respective plurality of range bins contains a sample from the respective receiver of the plurality of receivers;
• wherein each plurality of time slices is accumulated into a corresponding radar data cube of the two or more radar data cubes during a respective scan of the at least two or more scans;
• wherein the receive pipeline is configured to output each of the two or more radar data cubes to the processor;
• wherein the processor is configured to (i) selectively process a portion of each of the two or more radar data cubes to produce a respective partial Doppler output for each of the two or more radar data cubes, and (ii) discard the two or more radar data cubes;
• wherein a portion of a radar data cube comprises a time series of samples for at least one range bin of each receiver of the plurality of receivers;
• and
• wherein the processor is configured to store in memory a full Doppler output by successively numerically accumulating together each of the partial Doppler outputs to form the full Doppler output.