Pulse radar device

• US 6,646,592 B2
• Filed: 11/13/2002
• Issued: 11/11/2003
• Est. Priority Date: 02/14/2002
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Matsuoka, Katsuji
• Primary Examiner(s): Lobo, Ian J.
• Application Number:
  US10/292,588
• Publication Number:
  US 20030151545A1
• Time in Patent Office: 363 Days
• Field of Search: 342/118, 342/134, 342/145, 342/135, 342/70
• US Class Current: 342/134
• CPC Class Codes: G01S 13/04 Systems determining presence of a target based on relative movement of target G01S13/56
• CPC Class Codes: G01S 13/103 particularities of the measurement of the distance G01S13/12, G01S13/14, G01S13/16, G01S13/18 and G01S13/20 take precedence
• CPC Class Codes: G01S 7/2921 based on data belonging to one radar period

Abstract

A pulse radar device includes a transmitting unit, a receiving unit, a first integrating unit for sampling a reception signal at predetermined time intervals from transmission and integrating results of a predetermined number of times of the sampling at each sampling timing, a differential operating unit for, each time a predetermined time period has passed, reading results of the integrating at each sampling timing and differentiating the read results of the integrating in a sampling direction, a second integrating unit for integrating absolute values of a predetermined number of outputs from the differential operating unit at each sampling timing, a peak detecting unit for detecting the peak of an output from the second integrating unit, a distance measuring and detecting unit for calculating a distance to an object and judging presence or absence of an object based on an output from the peak detecting unit and the like.

Claims

1. A pulse radar device comprising:

a transmitting means for transmitting a pulse-shaped, radio wave;

a receiving means for receiving a reflection wave generated by reflection of the radio wave transmitted from the transmitting means by an object and outputting a reception signal;

a comparator means for converting the reception signal from the receiving means into a binary signal by comparing the reception signal with a preset and predetermined level;

a first integrating means for sampling an output from the comparator means at predetermined time intervals from transmission and integrating results of a predetermined number of times of the sampling at each sampling timing;

a differential operating means for, each time a predetermined time period has passed, reading results of the integrating by the first integrating means at each sampling timing and differentiating the read results of the integrating in a sampling direction;

a second integrating means for integrating absolute values of a predetermined number of outputs from the differential operating means at each sampling timing;

a peak detecting means for detecting a peak based on an output from the second integrating means;

a distance measuring and detecting means for calculating a distance to the object and judging presence or absence of the object based on an output from the peak detecting means; and

a timing control means for performing timing control for the transmission of the radio wave, the reception of the reflection wave, and signal processing.

2. A pulse radar device according to claim 1,

wherein the differential operating means obtains a difference between outputs from the first integrating means at a sampling timing with interest and at a neighboring sampling timing thereof.

3. A pulse radar device according to claim 1,

wherein the differential operating means obtains a difference between outputs from the first integrating means at a sampling timing with interest and at a neighboring sampling timing and a difference between outputs from the first integrating means at the sampling timing with interest and at a sampling timing next to the neighboring sampling timing, and obtains a sum of the differences.

4. A pulse radar device according to claim 1,

wherein the peak detecting means outputs each sampling timing, out of sampling timings at each of which a result of the integrating by the second integrating means at each sampling timing becomes extremely large, at which a result of the integrating exceeds a preset value.

5. A pulse radar device according to claim 1, further comprising a detection threshold value setting means for setting a detection threshold value based on a result of the integrating of the second integrating means,

wherein the peak detecting means outputs each sampling timing, out of sampling timings at each of which a result of the integrating by the second integrating means at each sampling timing becomes extremely large, at which a result of the integrating exceeds the detection threshold value set by the detection threshold value setting means.

6. A pulse radar device according to claim 5,

wherein the detection threshold value setting means obtains a mean value of a predetermined number of previous results of the integrating by the second integrating means at each sampling timing and sets the mean value as a noise level at each specific sampling timing, obtains a mean value of results of the integrating by the second integrating means at at least one sampling timing and sets the mean value as the noise level at each sampling timing other than the specific sampling timing, and calculates the detection threshold value based on the noise levels.

7. A pulse radar device according to claim 4,

wherein the distance measuring and detecting means includes:

a distance calculating means for calculating a distance based on a result of the integrating by the second integrating means at the sampling timing outputted from the peak detecting means and results of the integrating by the second integrating means at sampling timings before and after the outputted sampling timing; and

a detecting and judging means for judging whether an object exists based on a result of the calculation by the distance calculating means.

8. A pulse radar device according to claim 1, further comprising a ground level changing means for changing a ground level of the reception signal from the receiving means based on a result of the integrating by the first integrating means.

9. A pulse radar device according to claim 8, further comprising a ground level control means for obtaining a mean value of results of the integrating by the first integrating means at each sampling timing and, if the mean value exceeds a predetermined range, outputting a signal for changing the ground level to the ground level changing means.

10. A pulse radar device according to claim 2,

wherein the peak detecting means outputs each sampling timing, out of sampling timings at each of which a result of the integrating by the second integrating means at each sampling timing becomes extremely large, at which a result of the integrating exceeds a preset value.

11. A pulse radar device according to claim 3,

wherein the peak detecting means outputs each sampling timing, out of sampling timings at each of which a result of the integrating by the second integrating means at each sampling timing becomes extremely large, at which a result of the integrating exceeds a preset value.

12. A pulse radar device according to claim 2, further comprising a detection threshold value setting means for setting a detection threshold value based on a result of the integrating of the second integrating means,

wherein the peak detecting means outputs each sampling timing, out of sampling timings at each of which a result of the integrating by the second integrating means at each sampling timing becomes extremely large, at which a result of the integrating exceeds the detection threshold value set by the detection threshold value setting means.

13. A pulse radar device according to claim 3, further comprising a detection threshold value setting means for setting a detection threshold value based on a result of the integrating of the second integrating means,

wherein the peak detecting means outputs each sampling timing, out of sampling timings at each of which a result of the integrating by the second integrating means at each sampling timing becomes extremely large, at which a result of the integrating exceeds the detection threshold value set by the detection threshold value setting means.

14. A pulse radar device according to claim 5,

wherein the distance measuring and detecting means includes:

a distance calculating means for calculating a distance based on a result of the integrating by the second integrating means at the sampling timing outputted from the peak detecting means and results of the integrating by the second integrating means at sampling timings before and after the outputted sampling timing; and

a detecting and judging means for judging whether an object exists based on a result of the calculation by the distance calculating means.

15. A pulse radar device according to claim 6,

wherein the distance measuring and detecting means includes:

a distance calculating means for calculating a distance based on a result of the integrating by the second integrating means at the sampling timing outputted from the peak detecting means and results of the integrating by the second integrating means at sampling timings before and after the outputted sampling timing; and

a detecting and judging means for judging whether an object exists based on a result of the calculation by the distance calculating means.

16. A pulse radar device according to claim 2, further comprising a ground level changing means for changing a ground level of the reception signal from the receiving means based on a result of the integrating by the first integrating means.

17. A pulse radar device according to claim 3, further comprising a ground level changing means for changing a ground level of the reception signal from the receiving means based on a result of the integrating by the first integrating means.

18. A pulse radar device according to claim 4, further comprising a ground level changing means for changing a ground level of the reception signal from the receiving means based on a result of the integrating by the first integrating means.

19. A pulse radar device according to claim 5, further comprising a ground level changing means for changing a ground level of the reception signal from the receiving means based on a result of the integrating by the first integrating means.

20. A pulse radar device according to claim 6, further comprising a ground level changing means for changing a ground level of the reception signal from the receiving means based on a result of the integrating by the first integrating means.