Systems and methods for range-rate dealiasing using position consistency
Systems and methods for operating radar systems. The methods comprise, by a processor: receiving point cloud information generated by at least one radar device and a spatial description for an object; generating a plurality of point cloud segments by grouping data points of the point cloud information based on the spatial description; arranging the point cloud segments in a temporal order to define a radar tentative track; performing dealiasing operations using the radar tentative track to generate tracker initialization information; and using the tracker initialization information to generate a track for the object.
1. A method for operating a radar system, comprising, by a processor:
receiving first point cloud information generated by a first radar device, second point cloud information from a second radar device, and a spatial description for an object that was detected by the radar system, the first and second radar devices having different locations in the radar system;
generating a plurality of point cloud segments by grouping data points of the first point cloud information and data points of the second point cloud information based on the spatial description;
arranging the point cloud segments in a temporal order to define a radar tentative track;
performing dealiasing operations using the radar tentative track to generate tracker initialization information, where the dealiasing operations use, as inputs to a dealiasing algorithm, an average range-rate value and an average velocity ambiguity value for each said point cloud segment and said radar tentative track; and
using the tracker initialization information to generate a track for the object.
2. The method according to claim 1 , wherein two data points are grouped together to form a point cloud segment of the plurality of point cloud segments when a Euclidean distance between the two data points is less than a threshold value.
3. The method according to claim 1 , wherein two data points are grouped together to form a point cloud segment of the plurality of point cloud segments when an absolute difference between range-rate angles of the two data points is less than a threshold value.
4. The method according to claim 1 , wherein two data points are grouped together to form a point cloud segment of the plurality of point cloud segments when a difference between range-rate amplitudes of the two data points is less than a threshold value.
5. The method according to claim 1 , wherein the dealiasing operations further comprise:
computing a range-rate difference value between the average range-rate value for a given point cloud segment and the average range-rate value for the radar tentative track; and
comparing the range-rate difference value to a threshold value.
6. The method according to claim 5 , wherein the dealiasing operations further comprise determining that the range-rate difference value is close to the average velocity ambiguity for the radar tentative track when the range-rate difference is greater than the threshold value.
7. The method according to claim 6 , wherein the dealiasing operations further comprise determining that an edge case exists when a determination is made that the range-rate difference value is close to the average velocity ambiguity for the radar tentative track.
8. The method according to claim 1 , wherein the dealiasing operations comprise performing a position consistency dealiasing algorithm.
9. The method according to claim 8 , wherein the position consistency dealiasing algorithm comprises estimating an average range-rate in accordance with mathematical equation
RR estimate =( P t −P s )/( TV average-T −TV average-S )
where RR estimate is an estimated average range-rate, P t is a position of the radar tentative track, P s is a position of a given point cloud segment, TV average-T is an average time of validity for the radar tentative track, and TV average-S is an average time of validity for the given point cloud segment.
10. The method according to claim 9 , wherein the position consistency dealiasing algorithm further comprises determining a plurality of possible K values in accordance with mathematical equation
| RR measured +K*B average-S |≤v g
where RR measured is a measured range rate for a given data point, B average-S is an average velocity ambiguity for a given point cloud segment, and v g is a rational maximum speed over ground.
11. The method according to claim 10 , wherein the position consistency dealiasing algorithm further comprises generating a plurality of range-rate hypotheses values in accordance with mathematical equation
RR hypothesis =RR average-T +K*B average-S
where RR hypothesis is a range-rate hypotheses value, and RR average-T is an average range-rate for the radar tentative track.
12. The method according to claim 11 , wherein the position consistency dealiasing algorithm further comprises accepting a hypothesis when a respective one of the plurality of range-rate hypotheses values is less than a pre-defined threshold.
13. The method according to claim 12 , wherein the position consistency dealiasing algorithm further comprises determining an absolute difference between the estimated average range-rate and a given range-rate hypothesis value of the plurality of range-rate hypotheses values.
14. The method according to claim 13 , wherein the position consistency dealiasing algorithm is considered successful when the absolute difference between an estimated range-rate and a hypothesis range-rate is greater than a threshold.
15. The method according to claim 14 , wherein the dealiasing operations further comprise determining a true range-rate value when the position consistency dealiasing algorithm is considered successful.
16. The method according to claim 15 , wherein the dealiasing operations further comprise using the true range-rate to generate the tracker initialization information.
17. A system, comprising:
a processor; and
a non-transitory computer-readable storage medium comprising programming instructions that are configured to cause the processor to implement a method for operating a radar system, wherein the programming instructions comprise instructions to:
receive first point cloud information generated by a first radar device, second point cloud information from a second radar device, and a spatial description for an object that was detected by the radar system, the first and second radar devices having different locations in the radar system;
generate a plurality of point cloud segments by grouping data points of the first point cloud information and data points of the second point cloud information based on the spatial description;
arrange the point cloud segments in a temporal order to define a radar tentative track;
perform dealiasing operations using the radar tentative track to generate tracker initialization information, where the dealiasing operations use, as inputs to a dealiasing algorithm, an average range-rate value and an average velocity ambiguity value for each said point cloud segment and said radar tentative track; and
use the tracker initialization information to generate a track for the object.
18. The system according to claim 17 , wherein two data points are grouped together to form a point cloud segment of the plurality of point cloud segments when a Euclidean distance between the two data points is less than a threshold value.
19. The system according to claim 17 , wherein two data points are grouped together to form a point cloud segment of the plurality of point cloud segments when an absolute difference between range-rate angles of the two data points is less than a threshold value.
20. The system according to claim 17 , wherein two data points are grouped together to form a point cloud segment of the plurality of point cloud segments when a difference between range-rate amplitudes of the two data points is less than a threshold value.
21. The system according to claim 17 , wherein the dealiasing operations further comprise:
computing a range-rate difference value between the average range-rate value for a given point cloud segment and the average range-rate value for the radar tentative track; and
comparing the range-rate difference value to a threshold value.
22. The system according to claim 21 , wherein the dealiasing operations further comprise determining that the range-rate difference value is close to the average velocity ambiguity for the radar tentative track when the range-rate difference is greater than the threshold value.
23. The system according to claim 22 , wherein the dealiasing operations further comprise determining that an edge case exists when a determination is made that the range-rate difference value is close to the average velocity ambiguity for the radar tentative track.
24. The system according to claim 17 , wherein the dealiasing operations comprise performing a position consistency dealiasing algorithm.
25. The system according to claim 24 , wherein the position consistency dealiasing algorithm comprises estimating an average range-rate in accordance with mathematical equation
RR estimate =( P t −P s )/( TV average-T −TV average-S )
where RR estimate is an estimated average range-rate, P t is a position of the radar tentative track, P s is a position of a given point cloud segment, TV average-T is an average time of validity for the radar tentative track, and TV average-S is an average time of validity for the given point cloud segment.
26. The system according to claim 25 , wherein the position consistency dealiasing algorithm further comprises determining a plurality of possible K values in accordance with mathematical equation
| RR measured +K*B average-S |≤v g
where RR measured is a measured range rate for a given data point, B average-S is an average velocity ambiguity for a given point cloud segment, and v g is a rational maximum speed over ground.
27. The system according to claim 26 , wherein the position consistency dealiasing algorithm further comprises generating a plurality of range-rate hypotheses values in accordance with mathematical equation
RR hypothesis −RR average-T +K*B average-S
where RR hypothesis is a range-rate hypotheses value, and RR average-T is an average range-rate for the radar tentative track.
28. The system according to claim 27 , wherein the position consistency dealiasing algorithm further comprises accepting a hypothesis when a respective one of the plurality of range-rate hypotheses values is less than a pre-defined threshold.
29. The system according to claim 28 , wherein the position consistency dealiasing algorithm further comprises determining an absolute difference between the estimated average range-rate and a given range-rate hypothesis value of the plurality of range-rate hypotheses values.
30. The system according to claim 29 , wherein the position consistency dealiasing algorithm is considered successful when the absolute difference between an estimated range-rate and a hypothesis range-rate is greater than a threshold.
31. The system according to claim 30 , wherein the dialiasing operations further comprise determining a true range-rate value when the position consistency dealiasing algorithm is considered successful.
32. The system according to claim 31 , wherein the dialiasing operations further comprise using the true range-rate to generate the tracker initialization information.
33. A non-transitory computer-readable medium that stores instructions that are configured to, when executed by at least one computing device, cause the at least one computing device to perform operations comprising:
receiving first point cloud information generated by a first radar device, second point cloud information from a second radar device, and a spatial description for an object that was detected by the radar system, the first and second radar devices having different locations in the radar system;
generating a plurality of point cloud segments by grouping data points of the first point cloud information and data points of the second point cloud information based on the spatial description;
arranging the point cloud segments in a temporal order to define a radar tentative track;
performing dealiasing operations using the radar tentative track to generate tracker initialization information, where the dealiasing operations use, as inputs to a dealiasing algorithm, an average range-rate value and an average velocity ambiguity value for each said point cloud segment and said radar tentative track; and
using the tracker initialization information to generate a track for the object.