Radar field-of-view enhancement method and apparatus for matching field-of-view to desired detection zone

• US 6,452,534 B1
• Filed: 04/06/2001
• Issued: 09/17/2002
• Est. Priority Date: 08/04/2000
• Status: Expired due to Term

• Current Assignee: Veoneer, Inc. (SSW Partners LP)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Schaefer, Jeffrey, Zoratti, Paul Kirk
• Primary Examiner(s): Sotomayor, John B.
• Application Number:
  US09/806,964
• Time in Patent Office: 529 Days
• Field of Search: 342/70, 342/71, 342/72, 342/27, 342/28, 342/90, 342/93, 701/301, 340/435, 340/436, 340/901, 340/903
• US Class Current: 342/70
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/9315 Monitoring blind spots
• CPC Class Codes: G01S 2013/93274 on the side of the vehicles

Abstract

A radar field-of-view enhancement method particularly adapted for vehicle radar detection systems having a specified detection zone. In accordance with the invention, a pair of discrete radar beams are employed having differing arc widths. Return signals from the discrete beams are compared and related to the area of a desired detection zone. This approach increases the reliability of detection in the detection zone while minimizing false alarms and missed detection areas. The beams are alternately switched on using discrete sources or by implementing a discrete phase shifting element interposed between the sources.

Claims

1. A radar detection system for a vehicle having a desired detection zone spatially associated with said vehicle, comprising:

a first radar source generating a first radar beam pattern having a first arc beam width with said first beam pattern superimposed upon said detection zone to substantially encompass said detection zone, said first radar source producing a first object detection signal indicating the presence of an object within said first beam pattern, said first beam pattern including a false alarm area outside said detection zone,

a second radar source generating a second beam pattern having a second arc beam width having an angular measure less than said first arc beam width with said second radar pattern superimposed upon said detection zone to encompass less than the entirety of said detection zone and not encompassing at least a portion of said false alarm area, said second radar source producing a second object detection signal indicating the presence of an object within said second beam pattern, and

a signal processor for comparing said first object detection signal with said second object detection signal and producing a composite detection signal not affected by objects in at least a portion of said false alarm area.

2. A radar detection system in accordance with claim 1 wherein said vehicle comprises a motor vehicle having an outside rearview mirror with said detection zone being oriented with respect to said mirror.

3. A radar detection system in accordance with claim 1 further comprising:

said first arc beam width measuring about 55 degrees.

4. A radar detection system in accordance with claim 1 further comprising:

said second arc beam width measuring about 40 degrees.

5. A radar detection system in accordance with claim 2 further comprising:

said detection area measuring about 4 meters laterally from said vehicle measured from said mirror and about 6 meters rearwardly from said vehicle measured from said mirror.

6. A radar detection system in accordance with claim 5 further comprising:

said first beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

7. A radar detection system in accordance with claim 5 further comprising:

said second beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

8. A radar detection system in accordance with claim 5 further comprising:

said first beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6.5 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

9. A radar detection system in accordance with claim 5 further comprising:

said second beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6.5 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

10. A radar detection system in accordance with claim 1 wherein said first and second beam patterns are each defined by pairs of radial lines and wherein a radial line of each of said beam first and second beam patterns are coincident.

11. A method of detecting the presence of an object present in a desired detection zone spatially associated with a vehicle, comprising:

generating a first radar beam pattern having a first arc beam width with said first beam pattern superimposed upon said detection zone to substantially encompass said detection zone,

producing a first object detection signal from said first radar beam pattern indicating the presence of an object within said first beam pattern, said first beam pattern including a false alarm area outside said detection zone,

generating a second beam pattern having a second arc beam width having an angular measure less than said first arc beam width with said second radar pattern superimposed upon said detection zone to encompass less than the entirety of said detection zone and not encompassing at least a portion of said false alarm area,

producing a second object detection signal from said second beam pattern indicating the presence of an object within said second beam pattern, and

comparing said first object detection signal with said second object detection signal and producing a composite detection signal not affected by objects in at least a portion of said false alarm area.

12. A method of detecting the presence of an object in accordance with claim 11 wherein said vehicle comprises a motor vehicle having an outside rearview mirror and orienting said detection zone with respect to said mirror.

13. A method of detecting the presence of an object in accordance with claim 11 wherein said first arc beam width measuring about 55 degrees.

14. A method of detecting the presence of an object in accordance with claim 11 wherein

said second arc beam width measuring about 40 degrees.

15. A method of detecting the presence of an object in accordance with claim 11 wherein

said detection area measuring about 4 meters laterally from said vehicle measured from said mirror and about 6 meters rearwardly from said vehicle measured from said mirror.

16. A method of detecting the presence of an object in accordance with claim 15 wherein:

said first beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

17. A method of detecting the presence of an object in accordance with claim 15 wherein said second beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

18. A method of detecting the presence of an object in accordance with claim 15 wherein said first beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6.5 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

19. A radar detection system in accordance with claim 15 further comprising:

said second beam pattern defining a first region defined by an arc having a radius of about 4 meters from said mirror, and a second arc having a radius of about 6.5 meters from said mirror, and wherein said false alarm area resides in an area bounded between said first and second regions.

20. A method of detecting the presence of an object in accordance with claim 11 wherein said first and second beam patterns are each defined by pairs of radial lines and wherein a radial line of each of said beam first and second beam patterns are coincident.