Detection device and detection method

Abstract

A detection device for detecting a body entering a predetermined range has a transmission means for periodically radiating a pulse-like transmission signal by way of an electromagnetic wave to which a band restriction has been applied, a first reception means and a second reception means, and a judgment means. Each of the reception means performs receiving, as a reception signal, the electromagnetic wave reflected by the body, periodic sampling of the reception signal after a predetermined delay time has elapsed from transmission, and judging, based on a result of the periodic sampling, whether the body exists. The judgment means judges, based on judgment results of each of the first reception means and the second reception means, whether the body has entered into the predetermined range, and outputs a judgment result.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a constitution example of a conventional pulse sensor.

FIG. 2 is a timing chart explaining an operation of a sampling in a case where the conventional pulse sensor in FIG. 1 has transmitted a transmission signal of an ideal impulse waveform.

FIG. 3 is a timing chart explaining a detection operation in a case where the conventional pulse sensor in FIG. 1 has transmitted an ideal pulse as the transmission signal.

FIG. 4 is a timing chart explaining the operation of the sampling in a case where the conventional pulse sensor in FIG. 1 has transmitted a transmission signal to which a band restriction has been applied.

FIG. 5 is a timing chart explaining the detection operation in the case where the conventional pulse sensor in FIG. 1 has transmitted the transmission signal to which the band restriction has been applied.

FIG. 6 is a view explaining one example of a detection possible range of the conventional pulse sensor in FIG. 1 in a case where the transmission signal of the ideal impulse waveform is outputted.

FIG. 7 is a view explaining one example of the detection possible range of the conventional pulse sensor in FIG. 1 in a case where the transmission signal to which the band restriction has been applied is outputted.

FIG. 8 is a view explaining a technique according to one or more embodiments of the present invention, which explains one example of the detection possible range of a pulse sensor to which one or more embodiments of the present invention has been applied.

FIG. 9 is a view showing a constitution example of a pulse sensor as one embodiment of a detection device to which one or more embodiments of the present invention has been applied.

FIG. 10 is a view explaining the technique according to one or more embodiments of the present invention, which explains other example of the detection possible range of the pulse sensor to which one or more embodiments of the present invention has bee applied.

FIG. 11 is a block diagram showing other example of a constitution of all or one portion of the detection device to which one or more embodiments of the present invention is applied.

Claims

1. A detection device for detecting a body entering a predetermined range, comprising: a transmission means for periodically radiating a pulse-like transmission signal by way of an electromagnetic wave to which a band restriction has been applied;a first reception means and a second reception means, each of which perform: receiving, as a reception signal, the electromagnetic wave reflected by the body,periodic sampling of the reception signal after a predetermined delay time has elapsed from transmission, andjudging, based on a result of the periodic sampling, whether the body exists; anda judgment means for: judging, based on judgment results of each of the first reception means and the second reception means, whether the body has entered into the predetermined range, andoutputting a judgment result,wherein the delay time of the second reception means is deviated from the delay time of the first reception means by a half-period of a wave of a main frequency of the transmission signal.

2. A detection device according to claim 1, wherein the delay time of the second reception means is set to be longer than the delay time of the first reception means by the half-period of the wave of the main frequency of the transmission signal.

3. A detection device according to claim 1, wherein: the predetermined range is a distance from the detection device of less than one meter, anda shape of the body is variable.

4. A detection method in a detection device, wherein the detection device: periodically radiates a pulse-like transmission signal by way of an electromagnetic wave to which a band restriction has been applied,receives, as a reception signal, the electromagnetic wave reflected by a body, anddetects, based on the reception signal, the body that has entered into a predetermined range,the detection method comprising steps of:individually performing, in two systems, periodic sampling of the reception signal after a predetermined delay time has elapsed from transmission of the transmission signal and then judging, based on a result of the periodic sampling, whether the body exists, andjudging, based on judgment results of each of the two systems, whether the body has entered into the predetermined range, and outputting a judgment result,wherein the delay time of one of the two systems is deviated from the delay time of another of the two systems, by a half-period of a wave of a main frequency of the transmission signal.