Signal modeling for unambiguous range rate estimation

A non-transitory computer-readable storage media comprising instructions that, when executed, cause a processor to:

• transmit, from a radar system, radar signals for a frame by interleaving two different groups of chirps, including a first group and a second group, into an ordered sequence of chirps such that each consecutive pair of chirps includes an initial chirp from the first group and a subsequent chirp from the second group, one of the two groups including up-chirps that that increase in frequency during transmission and the other of the two groups including down-chirps that decrease in frequency during transmission;
• identify, based on radar returns obtained in response to transmission of the radar signals, initial range and Doppler measurements of peak detections associated with each of the two groups for the frame;
• select, from among a plurality of ambiguity terms used for unambiguously estimating range rates for detections, a first ambiguity term associated with the first group of chirps and a second ambiguity term associated with the second group of chirps, the first and second ambiguity terms being selected independently, with the first ambiguity term being selected based on the initial range and Doppler measurements of the peak detections only from the first group of chirps and the second ambiguity term being selected based on the initial range and Doppler measurements only from the second group of chirps;
• and
• use the ambiguity term selected for each of the two groups to estimate an unambiguous range rate for detections associated with each of the two groups.

A system comprising a processor configured to:

• transmit radar signals for a frame by interleaving two different groups of chirps, including a first group and a second group, into an ordered sequence of chirps such that each consecutive pair of chirps includes an initial chirp from the first group and a subsequent chirp from the second group;
• identify, based on radar returns obtained in response to transmission of the radar signals, initial range and Doppler measurements of peak detections associated with each of the two groups, one of the two groups including up-chirps that increase in frequency during transmission and the other of the two groups including down-chirps that decrease in frequency during transmission;
• select, from among a plurality of ambiguity terms used for unambiguously estimating range rates for detections, a first ambiguity term associated with the first group of chirps and a second ambiguity term associated with the second group of chirps, the first and second ambiguity terms being selected independently, with the first ambiguity term being selected based on the initial range and Doppler measurements of the peak detections only from the first group of chirps and the second ambiguity term being selected based on the initial range and Doppler measurements only from the second group of chirps;
• and
• use the ambiguity term selected for each of the two groups to estimate an unambiguous range rate for detections associated with each of the two groups.