Radar apparatus and object detecting method

2:

• The radar apparatus according to claim 1, wherein the object detection processor comprises:
• a regular data acquisition unit which regularly acquires To sampling points by sampling performed for the each predetermined discrete time on the signal including the repetitive waveforms of the reflection signal, where To is an integer that is larger than Tp;
• and
• a first judgment threshold value generator which calculates (To−Tp) sets of amplitude differences in the Tp sampling points among the To sampling points regularly acquired, and generates a first judgment threshold value for detection of presence or absence of the target object using the (To−Tp) sets of amplitude differences.

3:

• The radar apparatus according to claim 2, wherein the object detection processor further comprises:
• a measurement data acquisition unit which successively acquires (Tp+1) sampling points by sampling performed for the each prescribe discrete time on the signal including the repetitive waveforms of the reflection signal;
• and
• an amplitude difference judging unit which judges presence or absence of the target object based on a difference between the first judgment threshold value and a maximum value of absolute values of amplitude differences in the successively acquired (Tp+1) sampling points.

4:

• The radar apparatus according to claim 3, wherein:
• the radar apparatus comprises a plurality of antenna branch processors each serving as the antenna branch processor;
• and
• the object detection processor further comprises:
• a measurement data selector which selects a discrete time that is a range bin of signals, at which the target object is judged to be detected, including repetitive waveforms of a plurality of reflection signals;
• and
• a distance-direction delay profile generator which calculates a distance-direction delay profile based on the signals, corresponding to the range bin, including the repetitive waveforms of the plurality of reflection signals and direction vectors including amplitude and phase difference information corresponding to an azimuth angle of an incoming direction of the reflection signals, and estimates a distance from the radar apparatus to the target object and an azimuth angle of the target object based on a peak value of the calculated distance-direction delay profiles.

5:

• The radar apparatus according to claim 3, wherein:
• the radar apparatus comprises a plurality of antenna branch processors each serving as the antenna branch processor;
• and
• the object detection processor further comprises:
• a first distance-direction delay profile generator which calculates first distance-direction delay profiles based on a complex signal mean value including repetitive waveforms of a plurality of reflection signals and a direction vector including amplitude and phase difference information corresponding to an azimuth angle of an incoming direction of the reflection signals;
• a second judgment threshold value generator which generates a second judgment threshold value for detection of presence or absence of the object based on a cumulative probability distribution of the first distance-direction delay profiles;
• a measurement data selector which selects a discrete time that is a range bin of signals, at which the target object is judged to be detected, including repetitive waveforms of a plurality of reflection signals;
• a second distance-direction delay profile generator which calculates a second distance-direction delay profile based on a complex average of the signals, corresponding to the range bin, including the repetitive waveforms of the plurality of reflection signals and the direction vector;
• and
• an object detection judging unit which estimates a distance from the radar apparatus to the target object and an azimuth angle of the target object based on a difference between the second distance-direction delay profile and the second judgment threshold value.

6:

• The radar apparatus according to claim 3, wherein:
• the radar apparatus is installed in a movable body;
• and
• the object detection processor further comprises:
• a movement state acquisition unit which acquires a movement state of the movable body;
• a first judgment threshold value storage which stores a predetermined judgment threshold value for detection of presence or absence of the object;
• and
• a first switch which switches between the predetermined judgment threshold value and the first judgment threshold value according to the movement state of the movable body, and outputs the resulting judgment threshold value to the amplitude difference judging unit.

7:

• The radar apparatus according to claim 5, wherein:
• the radar apparatus is installed in a movable body;
• and
• the object detection processor further comprises:
• a movement state acquisition unit which acquires a movement state of the movable body;
• a second judgment threshold value storage which stores predetermined third and fourth judgment threshold values, being different from each other, for detection of presence or absence of the target object;
• and
• a second switch which switches between the third predetermined judgment threshold value and the first judgment threshold value according to the movement state of the movable body and outputs the resulting judgment threshold value to the amplitude difference judging unit, and switches between the fourth predetermined judgment threshold value and the second judgment threshold value according to the movement state of the movable body and outputs the resulting judgment threshold value to the object detection judging unit.

8:

• An object detection method in a radar apparatus, the object detection method comprising the steps of:
• transmitting, from a transmission antenna, a radar transmission signal having radio-frequency repetitive waveforms;
• receiving, by a reception antenna, a signal including repetitive waveforms of a reflection signal produced by reflection, by an object, of the radar transmission signal;
• sampling the signal including the repetitive waveforms of the reflection signal for each predetermined discrete time;
• and
• detecting presence or absence of a target object using amplitude differences in respective (Tp+1) sampling points by sampling on the signal including the repetitive waveforms of the reflection signal, where Tp is an integer.