Object detection device and object detection system
An object detection device includes: a transmission unit transmitting a transmission wave substantially at the same time with another transmission unit in another object detection device; a reception unit receiving a reception wave including surges corresponding to a result of return of the transmission wave by the transmission unit and another transmission wave by the another transmission unit in accordance with reflection by an object; an identification unit identifying a transmission source of the surges included in the reception wave; and a detection unit detecting information related to the object based on a correspondence relationship between a first peak of a first waveform indicating a first surge transmitted by the another transmission unit and received by the reception unit and a second peak of a second waveform indicating a second surge transmitted by the transmission unit and received by another reception unit provided in the another object detection device.
1 . An object detection device comprising:
a transmission unit configured to transmit a transmission wave substantially at the same time with another transmission unit provided in another object detection device;
a reception unit configured to receive a reception wave including a plurality of surges corresponding to a result of return of the transmission wave transmitted by the transmission unit and another transmission wave transmitted by the another transmission unit in accordance with reflection by an object;
an identification unit configured to identify a transmission source of the plurality of surges included in the reception wave; and
a detection unit configured to detect information related to the object based on a correspondence relationship between a first peak of a first waveform indicating a first surge transmitted by the another transmission unit provided in the another object detection device and received by the reception unit and a second peak of a second waveform indicating a second surge transmitted by the transmission unit and received by another reception unit provided in the another object detection device, the first peak and the second peak being specified based on an identification result of the identification unit and another identification unit provided in the another object detection device, wherein
the detection unit detects the information related to the object based on the correspondence relationship between the first peak included in the first waveform that is a first envelope waveform in a predetermined section of a signal level of the first surge and the second peak included in the second waveform that is a second envelope waveform in a predetermined section of a signal level of the second surge.
2 . The object detection device according to claim 1 , wherein
the detection unit detects the information related to the object based on at least one of the first peak and the second peak whose difference between a section length from a start of the predetermined section in the first envelope waveform to appearance of the first peak and a section length from appearance of the second peak in the second envelope waveform to an end of the predetermined section is within a predetermined range.
3 . The object detection device according to claim 2 , wherein
the detection unit specifies peaks whose signal levels of the first envelope waveform and the second envelope waveform are equal to or more than a predetermined threshold value corresponding to noise as the first peak and the second peak.
4 . The object detection device according to claim 1 , wherein
the transmission unit modulates the transmission wave by a predetermined modulation method to include identification information for identifying the object detection device, and then transmits the modulated transmission wave, and
the identification unit identifies the transmission source of the plurality of surges included in the reception wave based on a result of demodulating the reception wave by a demodulation method corresponding to the predetermined modulation method.
5 . The object detection device according to claim 1 , wherein
the object detection device is configured as an in-vehicle sonar that detects a distance to an object on a road surface as the information related to the object.
6 . An object detection system comprising:
a plurality of object detection devices each including a transmission unit configured to transmit a transmission wave substantially at the same time with another transmission unit provided in another object detection device, a reception unit configured to receive a reception wave including a plurality of surges corresponding to a result of return of the transmission wave transmitted by the transmission unit and another transmission wave transmitted by the another transmission unit in accordance with reflection by an object, and an identification unit configured to identify a transmission source of the plurality of surges included in the reception wave; and
a detection unit configured to detect information related to the object based on a correspondence relationship between a first peak of a first waveform indicating a first surge transmitted by the transmission unit of a first object detection device among the plurality of object detection devices and received by a second object detection device different from the first object detection device among the plurality of object detection devices and a second peak of a second waveform indicating a second surge transmitted by the transmission unit of the second object detection device and received by the reception unit of the first object detection device, the first peak and the second peak being specified based on an identification result by the identification unit of each of the plurality of object detection devices, wherein
the detection unit detects the information related to the object based on the correspondence relationship between the first peak included in the first waveform that is a first envelope waveform in a predetermined section of a signal level of the first surge and the second peak included in the second waveform that is a second envelope waveform in a predetermined section of a signal level of the second surge.
7 . The object detection device according to claim 1 , wherein the detection unit specifies the first peak and the second peak, which substantially coincide in a timing when a time series is reversed and detects a distance to the object to be detected by a time of flight method based on at least one of the first peak and the second peak.