Apparatus and method for detecting and correcting for blockage of an automotive radar sensor

• US 10,054,672 B2
• Filed: 08/31/2015
• Issued: 08/21/2018
• Est. Priority Date: 08/31/2015
• Status: Active Grant

• Current Assignee: Veoneer, Inc. (SSW Partners LP)
• Original Assignee: Veoneer US Inc. (SSW Partners LP)
• Inventors: Fetterman, Matthew, Preussner, Jonathan, Carlsen, Aret
• Primary Examiner(s): Windrich, Marcus E
• Application Number:
  US14/840,902
• Publication Number:
  US 20170059695A1
• Time in Patent Office: 1,086 Days
• Field of Search: 342 70- 72
• CPC Class Codes: G01S 13/582 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/584 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/726 Multiple target tracking
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/932 using own vehicle data, e.g. ground speed, steering wheel direction
• CPC Class Codes: G01S 2013/93271 in the front of the vehicles
• CPC Class Codes: G01S 7/4026 Antenna boresight
• CPC Class Codes: G01S 7/4039 of sensor or antenna obstruction, e.g. dirt- or ice-coating

Abstract

An automotive radar system and method transmit a plurality of radar signals into a region, detect reflected radar signals, and convert the reflected radar signals into digital data signals. A plurality of range-Doppler maps for the region are generated from the digital data signals, and the plurality of range-Doppler maps are averaged to generate an averaged range-Doppler map for the region. Data points in the averaged range-Doppler map are analyzed to detect blobs in the averaged range Doppler map. If a blob is detected in the averaged range-Doppler map, the radar detector is indicated to be unblocked.

Claims

1. An automotive radar system, comprising:

a radar transmitter for transmitting a plurality of radar signals into a region;

a radar detector for detecting reflected radar signals and converting the reflected radar signals into digital data signals; and

a processor that receives the digital data signals, generates a plurality of range-Doppler maps for the region over time and averages the plurality of range-Doppler maps to generate an averaged range-Doppler map for the region;

wherein

the processor analyzes data points in the averaged range-Doppler map to detect blobs in the averaged range Doppler map; and

wherein

if a blob is detected in the averaged range-Doppler map by the processor, the radar detector is indicated by the processor to be unblocked.

2. The automotive radar system of claim 1, wherein, if a blob is not detected in the averaged range-Doppler map by the processor, the radar detector is indicated by the processor to be blocked.

3. The automotive radar system of claim 1, wherein a blob in the averaged range-Doppler map is considered by the processor to be due to radar returns from an extended object which is stationary with respect to a ground surface in an environment in which the automotive radar system is operating.

4. The automotive radar system of claim 3, wherein the extended object is a surface of a road on which the host vehicle is traveling.

5. The automotive radar system of claim 3, wherein the extended object is a curb along a side of a road on which the host vehicle is traveling.

6. The automotive radar system of claim 1, wherein the plurality of range-Doppler maps comprise 150 range-Doppler maps.

7. The automotive radar system of claim 1, wherein the radar signals have a frequency of approximately 77 GHz.

8. The automotive radar system of claim 1, wherein, for each data point in the averaged range-Doppler map, the processor compares a value of the data point with a first threshold value.

9. The automotive radar system of claim 8, wherein, if the value of the data point exceeds the first threshold, the processor compares values of a plurality of neighboring data points in the averaged range-Doppler map to a second threshold value.

10. The automotive radar system of claim 9, wherein, if the values of the neighboring data points exceed the second threshold value, then the processor identifies the data point as a point in a blob.

11. The automotive radar system of claim 10, wherein, if a quantity of neighboring data points identified as points in a blob exceeds a predetermined threshold, then the processor determines that the neighboring data points constitute a blob.

12. The automotive radar system of claim 1, wherein the processor ceases analyzing data points in the averaged range-Doppler map if the radar system detects an object in the region that is unrelated to any blob detected in the averaged range-Doppler map.

13. A method of processing in an automotive radar system, the method comprising:

transmitting a plurality of radar signals into a region;

detecting reflected radar signals and converting the reflected radar signals into digital data signals;

generating from the digital data signals a plurality of range-Doppler maps for the region over time;

averaging the plurality of range-Doppler maps to generate an averaged range-Doppler map for the region;

analyzing data points in the averaged range-Doppler map to detect blobs in the averaged range Doppler map; and

if a blob is detected in the averaged range-Doppler map, indicating the radar detector to be unblocked.

14. The method of claim 13, wherein, if a blob is not detected in the averaged range-Doppler map, the radar detector is indicated to be blocked.

15. The method of claim 13, wherein a blob in the averaged range-Doppler map is considered to be due to radar returns from an extended object which is stationary with respect to a ground surface in an environment in which the automotive radar system is operating.

16. The method of claim 15, wherein the extended object is a surface of a road on which the host vehicle is traveling.

17. The method of claim 15, wherein the extended object is a curb along a side of a road on which the host vehicle is traveling.

18. The method of claim 13, wherein the plurality of range-Doppler maps comprise 150 range-Doppler maps.

19. The method of claim 13, wherein the radar signals have a frequency of approximately 77 GHz.

20. The method of claim 13, wherein analyzing data points in the averaged range-Doppler map comprises, for each data point in the averaged range-Doppler map, comparing a value of the data point with a first threshold value.

21. The method of claim 20, wherein analyzing data points in the averaged range-Doppler map comprises, if the value of the data point exceeds the first threshold, comparing values of a plurality of neighboring data points in the averaged range-Doppler map to a second threshold value.

22. The method of claim 21, wherein analyzing data points in the averaged range-Doppler map comprises, if the values of the neighboring data points exceed the second threshold value, identifying the data point as a point in a blob.

23. The method of claim 22, wherein analyzing data points in the averaged range-Doppler map comprises, if a quantity of neighboring data points identified as points in a blob exceeds a predetermined threshold, determining the neighboring data points to constitute a blob.

24. The method of claim 13, wherein analyzing data points in the averaged range-Doppler map is stopped if an object that is unrelated to any blob detected in the averaged range-Doppler map is detected in the region.