Radar system

• US 9,075,134 B2
• Filed: 12/12/2012
• Issued: 07/07/2015
• Est. Priority Date: 12/13/2011
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Abe, Yoshihiro, Mizutani, Akiyoshi
• Primary Examiner(s): Sotomayor, John B
• Application Number:
  US13/711,943
• Publication Number:
  US 20130147666A1
• Time in Patent Office: 937 Days
• Field of Search: 342 70- 72, 342 95- 97, 342/159
• US Class Current: 1/1
• CPC Class Codes: G01S 13/06 Systems determining position data of a target
• CPC Class Codes: G01S 13/345 using triangular modulation
• CPC Class Codes: G01S 13/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S13/46
• CPC Class Codes: G01S 13/584 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 3/74 Multi-channel systems specially adapted for direction-finding, i.e. having a single antenna system capable of giving simultaneous indications of the directions of different signals systems in which the directions of different signals are determined sequentially and displayed simultaneously G01S3/04, G01S3/14
• CPC Class Codes: G01S 7/354 Extracting wanted echo-signals Doppler systems G01S13/50

Abstract

A radar system for detecting positions of targets using a high resolution algorithm is presented. The number of incorrect target detections due to incorrect estimation of the number of radar reflections is reduced. A two-dimensional (azimuth and distance) peak having maximum power is detected, and a virtual beam formed centering on that peak. If that two-dimensional peak is buried in the virtual beam it is assumed to be a noise peak and removed. This is repeated for all two-dimensional peaks, thereby removing noise peaks and reducing the number of unnecessary target detections. The system can also correctly detect peaks that are close together at a certain resolution but have a power larger than the virtual beam.

Claims

1. A radar system comprising:

means for transmitting electromagnetic waves;

means for receiving electromagnetic waves reflected from targets;

means for estimating a position of each target that has reflected the electromagnetic waves, using a high-resolution algorithm, according to received signals acquired from the receiving means;

means for creating virtual beams having a predetermined beam width centering on respective targets'"'"' positions estimated by the estimating means; and

means for removing targets that are located within a range of the respective virtual beams and have a received power with respect to the respective target'"'"'s position that is smaller than a received power of the respective virtual beams.

2. The radar system according to claim 1, wherein:

the estimating means, the creating means, and the removing means are configured by a signal processor; and

the signal processor is configured to set a width of the virtual beam to a value corresponding to a desired resolution.

3. The radar system according to claim 2, wherein the signal processer is further configured to process the estimated targets in descending order of their power.

4. The radar system according to claim 3, wherein the signal processer is further configured to estimate, as the position, a two-dimensional position which is defined by both azimuth and distance.

5. The radar system according to claim 1, wherein:

the estimating means, the creating means, and the removing means are configured by a signal processor; and

the signal processer is configured to process the estimated targets in descending order of their power.

6. The radar system according to claim 1, wherein:

the estimating means, the creating means, and the removing means are configured by a signal processor; and

the signal processer is configured to estimate, as the position, a two-dimensional position which is defined by both azimuth and distance.

7. The radar system according to claim 2, wherein

the signal processer is further configured to estimate, as the position, a two-dimensional position which is defined by both azimuth and distance.

8. The radar system according to claim 1, wherein:

the signal processor is configured to extract temporary peaks and prepare a list indicating two-dimensional positions and powers of each of the temporary peaks;

the signal processor is configured to sort the temporary peaks in descending order of their power and register a temporary peak having a maximum power as a two-dimensional peak.

9. The radar system according to claim 8, wherein the creating means centers one of the virtual beams on the two-dimensional peak.

10. The radar system according to claim 9, wherein:

the signal processor is configured to determine if there is at least one temporary peak buried in the one of the virtual beams; and

the signal processor is configured to remove the at least one temporary peak buried in the one of the virtual beams from the list.