JP2019144188A - Radio wave sensor and device having the same - Google Patents

Abstract

To provide a radio wave sensor that can provide motion information on motions of a target object and distance information on the distance to the sensor, and a device having the sensor.SOLUTION: A radio wave sensor 100 includes: modulation signal generation means 102 for generating at least two modulation signals: selection means 106 for selecting at least one modulation signal; oscillation means 108 for modulating an oscillation frequency by modulation signals 104 and 105 generated by the modulation signal generation means 102; control means 128 for switching the selection means 106 by time division; a transmission antenna; a reception antenna 110 for receiving a reflection radio wave as a transmitted radio wave reflected by a target object and returned; wave detection means 111 connected to a transmission line 109, the wave detection means extracting the differential frequency signal between the frequency of a transmitted radio wave and the frequency of a received radio wave; a filter 115 for removing an undesired frequency component from the differential frequency signal 113; amplification means 119; AD conversion means 123; and data operation means 126 for operating and analyzing a digital signal 124.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a radio wave sensor, which transmits a radio wave to an object, receives a reflected wave reflected by the object, and analyzes a signal obtained by detecting a synthesized wave of the transmitted wave and the received wave. The present invention relates to a radio wave sensor for specifying operation information and distance information of an object and a device equipped with the same.

  Taking an example of a toilet in a general home or public place, in recent years, the installation of a warm water washing toilet seat has been advanced in the toilet in a general home or public place. Some models of hot water flush toilet seats are also on the market that automatically open and close the toilet lid, lift and lower the toilet seat, deodorize after the toilet, and wash the toilet after the toilet.

  Various human sensors are used to control these automatic movements. For example, a pyroelectric (PIR) sensor and a radio wave Doppler radar are used to detect that a person opens a toilet door and approaches a toilet (see Patent Document 1).

  To detect that a person is sitting on the toilet seat, a microswitch that turns on when the toilet seat sinks several millimeters when the weight is applied to the toilet seat, and detects that the person's buttocks are in contact with the toilet seat Capacitance change detection type sensor, pressure sensor that detects the pressure applied to the toilet seat when a person sits on the toilet seat, the intensity of the reflected infrared light by irradiating the waist with the infrared that the human waist is in the immediate vicinity of the toilet seat Infrared proximity sensors that detect by measuring

  Pyroelectric (PIR) sensors and infrared proximity sensors have the advantage of being able to detect human movement and the proximity of the human body at low cost and with high accuracy, but pyroelectric (PIR) sensors are also infrared proximity sensors. In addition, there is a disadvantage that a window for transmitting infrared rays is required.

The presence of infrared transmissive windows is not a problem when installing a warm water flush toilet seat in a general household toilet, but in a warm water flush toilet seat installed in a public toilet, a voyeur camera is placed inside the infrared transmissive window. Due to the danger, infrared transmissive windows tend to be avoided in warm water flush toilet seats installed in public toilets.
Therefore, radio wave Doppler radar is often used to detect that a person is approaching the toilet seat, and a microswitch or a capacitance change detection type proximity sensor is often used to detect that a person is sitting on the toilet seat. .

  Microswitches are mechanically simple, durable, and inexpensive. However, when a micro switch is used, the switch is turned on and off by a physical movement that sinks several millimeters when a person sits on the toilet seat, so the toilet seat sinks several millimeters downward at the moment of sitting on the toilet seat. For this reason, there are users who do not like the operation of sinking the toilet seat. In addition, there are users who do not like the clicking sound generated when the switch is turned on and off.

  On the other hand, the capacitance change detection type proximity sensor has a problem that it is expensive and that it is difficult to arrange in the toilet seat.

  In a general warm water washing toilet seat, a heater for warming the toilet seat is installed in the toilet seat. The heater needs to warm the entire surface of the toilet seat that touches the human skin, so it is placed almost on the entire surface of the toilet seat, but the capacitance change detection sensor for detecting human seating is also the part that touches the human skin. Since it has to be installed almost on the entire surface, there is a problem that the arrangement locations of both compete and the design of the mechanism becomes difficult.

  There are also attempts to use radio wave Doppler radar, which detects when a person approaches a toilet, to detect seating. However, radio wave Doppler radar is a radar that detects the movement of people, so if the person is completely stationary due to its characteristics, it will not be possible to detect the presence of the person, and the washing water will not be discharged. However, there is a problem that the toilet cleaning operation is performed or the deodorizing device is started as if the person is still sitting on the toilet seat but no longer exists.

Next, a conventional technique using a radio wave Doppler sensor will be described.
FIG. 4 shows a prior art 1 using a radio wave Doppler sensor, and is a block diagram of a hot water flush toilet seat 500 that uses a radio wave Doppler radar to detect human movement and uses a micro switch to detect seating.
An output signal 529 from the radio wave Doppler radar 501 and a seating detection micro switch 531 are connected to the central control microcomputer 530 for controlling the toilet seat opening / closing motor, the toilet seat lifting / lowering motor, the hot water washing water discharge valve, the toilet bowl washing water discharge valve, and the like. Has been. A signal oscillated by an oscillating means 508 that oscillates a radio frequency signal is connected to an antenna 510 via a transmission line 509.

  In some cases, the antenna 510 may be shared by the transmission antenna and the reception antenna, or the transmission antenna and the reception antenna may be provided separately. A transmission wave is transmitted from the antenna 510 to an object, that is, a human body (not shown), and a reflected wave reflected by the object, that is, the human body is received by the antenna 510 as a reception wave. When the object approaches the antenna 510, the frequency of the reflected wave, that is, the received wave becomes higher than the frequency of the transmitted wave due to the Doppler effect.

  On the other hand, when the object moves away from the antenna 510, the frequency of the reflected wave, that is, the received wave becomes lower than the frequency of the transmitted wave due to the Doppler effect. The difference in frequency between the transmitted wave and the received wave is approximately proportional to the moving speed of the object, that is, the human body. On the transmission line 509, a combined wave of a transmission wave and a reception wave exists.

  A detection means 511 is connected to the transmission line 509, a combined wave of the transmission wave and the reception wave is detected by the detection means 511, and a difference frequency signal 513 having a frequency difference between the transmission wave frequency and the reception wave frequency is obtained. Extracted.

  Since the differential frequency signal 513 includes unnecessary noise frequency components that are not related to frequency components generated by the movement of the human body, the signal 517 from which unnecessary noise frequency components have been removed by the filter 515 is extracted. As for the signal 517, the signal 521 amplified by several tens to several thousand times by the amplification unit 519 is converted into a digital signal 524 by the AD conversion unit 523 and input to the data calculation unit 526.

Since the digital signal 524 includes information on the moving speed of the human body due to the Doppler effect as described above, the signal 527 indicating that the movement of the human body is detected from the information on the moving speed of the human body by the data calculating means 526 It is generated and sent to the central control microcomputer 530.
When the central control microcomputer 530 receives a signal indicating that the movement of the human body has been detected, the central control microcomputer 530 determines that the human body has opened the toilet door and has approached the toilet. Instruct to open. In this case, when the toilet lid is opened and a person sits on the toilet seat, the toilet seat sinks several mm, the micro switch unit 531 is turned on, and the central control microcomputer 530 determines that the person is seated on the toilet seat.

FIG. 5 shows Prior Art 2 using a radio wave Doppler sensor, which is a block diagram of a hot water washing toilet seat 600 that uses a radio wave Doppler radar to detect the approach or separation of a person and a capacitance change type sensor to detect seating. is there.
In FIG. 5, the seating detection microswitch 531 is simply replaced with a seating detection capacitance change type sensor 631 as compared with FIG. 4. The operation is almost the same as that in FIG. 4, and only the method for detecting that a person is seated on the toilet seat is different. In the warm water washing toilet seat 600 of FIG. 5, when a person sits on the toilet seat, the skin of the person approaches the seating detection capacitance change type sensor 631, and thus the capacity increases. The central control microcomputer 630 obtains this change in capacity by calculation and recognizes that a person is seated on the toilet seat.

  FIG. 6 is a block diagram of a warm water washing toilet seat 700 using the radio wave Doppler radar for detecting the movement of the human body and detecting the seating, according to the prior art 3 using the radio wave Doppler sensor. In FIG. 6, the seating detection micro switch 531 is eliminated compared to FIG. 4, and the seating detection is also performed by the radio wave Doppler radar. In other words, radio wave Doppler radar knows the movement speed of people, so if the movement speed is fast, people open the toilet door and move toward the toilet seat, or leave the toilet seat and open the toilet door Judge. If the moving speed is low, it is determined that the user is seated on the toilet seat.

JP 2003-194924 A Japanese Patent No. 4293194

  The prior art 1 shown in FIG. 4 has the following problems. That is, when the human body motion detection radio wave Doppler radar 500 and the seating detection micro switch 531 are used together, the user feels that the toilet seat is depressed and the toilet seat is not properly fixed when the person is seated. Further, when the micro switch 531 is turned on, it makes a clicking sound. Also, when a person stands up, the toilet seat rises and feels like sticking to the buttocks. Further, when the micro switch 531 is turned off, an unpleasant sound is produced.

  The prior art 2 shown in FIG. 5 has the following problems. In the combined use of the radio wave Doppler radar 600 for detecting human motion and the capacitance change detection proximity sensor 631 for seating detection, the capacitance change detection proximity sensor 631 is expensive. Also difficult to install. A heater for warming a general warm water washing toilet seat is disposed on the entire toilet seat because it is necessary to warm the entire portion of the toilet seat touched by the skin of the toilet. However, a capacitance change detection proximity sensor 631 for detecting the seating of the person. In addition, since it must be installed on the entire part that is touched by human skin, the installation locations of both compete with each other, resulting in difficulty in mechanical design.

  The prior art 3 shown in FIG. 6 has the following problems. If the radio wave Doppler sensor 700 is used for both human motion detection and seating detection, if a person sits on the toilet seat and does not move for a long time, it is determined that the person is not seated, and hot water washing water is not discharged, However, it is determined that the person is still sitting on the toilet seat, and the toilet cleaning operation is performed, or the deodorizing device is activated.

In view of the above problems, an object of the present invention is to provide a radio wave sensor capable of obtaining operation information related to the movement of an object including a person and distance information between the object and the sensor and an apparatus equipped with the radio wave sensor.

In order to achieve the above object, the radio wave sensor of the present invention is
Modulation signal generating means for generating at least two or more modulation signals;
Selecting means for selecting one modulation signal from a plurality of modulation signals;
Oscillating means whose oscillation frequency is modulated by a modulation signal generated from the modulation signal generating means;
Control means for switching the selection means in a time-sharing manner;
A transmission antenna that transmits the signal oscillated by the oscillation means as a transmission radio wave;
A reception antenna that receives a reflected radio wave reflected from an object and returned by the object as a reception radio wave; a reception antenna that is provided separately from or shared with the transmission antenna;
Detecting means connected to a transmission line connecting the oscillating means and at least the transmitting antenna, and for extracting a differential frequency signal which is a difference between the frequency of the transmitted radio wave and the frequency of the received radio wave;
A filter that removes unnecessary frequency components from the differential frequency signal output by the detection means;
Amplifying means for amplifying the differential frequency signal selected by the filter;
AD conversion means for converting the differential frequency signal amplified by the amplification means into a digital signal;
It comprises data calculation means for calculating and analyzing a digital signal output from the AD conversion means.
According to the radio wave sensor of the present invention, the modulation of the radar mode can be switched in a time-division manner by the control means, and the operation of the object whether or not the object moves regardless of the moving direction of the object. Information and distance information to the object can be obtained.

In order to achieve the above object, another radio wave sensor of the present invention further includes:
A first detection means connected to a position of the first signal line length from the receiving antenna on the radio signal transmission / reception line, and for extracting a first differential frequency signal that is a difference between the frequency of the transmission radio wave and the frequency of the reception radio wave;
Second detection means connected to a position of the second signal line length from the receiving antenna on the transmission line, and for extracting a second differential frequency signal that is a difference between the frequency of the transmission radio wave and the frequency of the reception radio wave;
A first filter for removing unnecessary frequency components from the first differential frequency signal output by the first detection means;
A second filter for removing unnecessary frequency components from the second differential frequency signal 2 output by the second detection means;
First amplifying means for amplifying the signal selected by the first filter;
Second amplification means for amplifying the signal selected by the second filter;
AD conversion means for converting the first differential frequency signal amplified by the first amplification means and the second differential frequency signal amplified by the second amplification means into a digital value;
It is characterized by comprising.
In order to achieve the above object, according to another radio wave sensor of the present invention, in the above configuration, the radio wave transmitted from the transmission antenna is further reflected as a reception radio wave that is reflected by the object or obstacle. A receiving antenna provided separately from the transmitting antenna;
Delay means for delaying the signal output from the oscillating means;
First detection is performed by receiving a reception wave received from the reception antenna and a transmission wave output from the oscillating means, and extracting a first differential frequency signal having a frequency corresponding to the difference between the frequency of the transmission wave and the frequency of the reception wave. Means,
Delay means for delaying the signal output from the oscillating means;
A reception wave received from the reception antenna and a signal obtained by delaying the transmission wave output from the oscillation means by the delay means are input, and a second difference in frequency corresponding to the difference between the frequency of the transmission wave and the frequency of the reception wave A second detection means for extracting a frequency signal;
It is characterized by comprising. According to the radio wave sensor of the present invention, the modulation of the radar mode can be switched in a time division manner by the control means, and the motion information of the target object including the moving direction of the target object and the distance information to the target object can be obtained.

In the above configuration, the distance between the first detection means and the second detection means is preferably a distance corresponding to 1/8 wavelength of the transmission radio wave at the time of non-modulation.
The delay amount of the delay means preferably corresponds to a quarter wavelength of the signal without modulation output from the oscillation means.
The plurality of modulation signals preferably include at least two of a transmission radio wave frequency after modulation having a constant value, a stepwise increase or decrease, and a continuous increase or decrease.
The frequency of the transmission radio wave is preferably a frequency band of 10 GHz, 24 GHz, or 77 GHz.
The information processed by the data calculation means is preferably object operation information indicating whether the object is moving regardless of the moving direction and distance information from the transmitting antenna to the object. .
The information processed by the data calculation means is preferably the operation information of the object whether the object is approaching or moving away from the antenna and the distance information from the transmitting antenna to the object. Characterized by the
The processing method processed by the data calculation means preferably includes at least two of a radio wave Doppler radar method, a radio wave FMCW radar method, a radio wave FM linear standing wave method, and a radio wave pulse compression radar method.

In order to achieve the above object, an apparatus equipped with the radio wave sensor of the present invention includes any of the radio wave sensors described above.
In the above-described configuration, the device equipped with the radio wave sensor is preferably any one of a hot water washing toilet seat system, an automatic teller machine, and a multifunction printer.

  According to the radio wave sensor of the present invention, a radio wave is transmitted to an object, a reflected wave reflected by the object is received, and a signal obtained by detecting a combined wave of the transmitted wave and the received wave is analyzed. Thus, it is possible to provide the operation information of the object and the distance information about the object.

  According to the apparatus equipped with the radio wave sensor of the present invention, since the radio wave sensor that can be easily installed and can obtain the operation information of the target object and the distance information about the target object is used, For example, a warm water washing toilet seat system can be provided.

It is a block diagram of a warm water washing toilet seat system using a radio wave sensor concerning a 1st embodiment of the present invention. It is a block diagram of a warm water washing toilet seat system using a radio wave sensor concerning a 2nd embodiment of the present invention. It is a block diagram of a warm water washing toilet seat system using a radio wave sensor concerning a 3rd embodiment of the present invention. It is a block diagram which shows the prior art 1 using a Doppler sensor. It is a block diagram which shows the prior art 2 using a Doppler sensor. It is a block diagram which shows the prior art 3 using a Doppler sensor.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the scope of the present invention is not limited to the embodiments, and can be appropriately changed. In particular, the shape, dimensions, positional relationship, and the like of each member described in the drawings merely show conceptual matters, and can be changed according to the application scene. In the drawings, the same or corresponding members are denoted by the same reference numerals.

(First embodiment)
FIG. 1 is a block diagram of a warm water washing toilet seat system using a radio wave sensor 100 according to the first embodiment of the present invention.
The radio wave sensor 100 includes modulation signal generation units 102 and 103 that generate at least two or more modulation signals 104 and 105, a selection unit 106 that selects one modulation signal from the plurality of modulation signals, and a selection unit 106. An oscillating means whose oscillation frequency is modulated by a modulation signal generated from the control means 128, a control means 128 for switching the selecting means 106 in a time division manner, a transmission antenna 110 for transmitting a signal oscillated by the oscillating means 108 as a transmission radio wave, A radio wave transmitted from the transmission antenna 110 is reflected by an object or an obstacle and is reflected back. A reception antenna provided separately from or shared with the transmission antenna 110, and the oscillation means 108 and at least It is connected on the transmission line 109 connecting the transmitting antenna 110, and the frequency of the transmission radio wave and the frequency of the reception radio wave A detection unit 111 that extracts a differential frequency signal that is a difference, a filter 115 that removes unnecessary frequency components from the difference signal output by the detection unit 111, an amplification unit 119 that amplifies a signal selected by the filter 115, and an amplification AD conversion means 123 for converting the differential frequency signal 121 amplified by the means 119 into a digital value, and data calculation means 126 for calculating and analyzing the digital signal 124 output from the AD conversion means 123. The
The radio wave sensor of the present invention can be used for various loads, obstacles, animals, and the like, for example. However, in the following description, the radio wave sensor is described as a radio wave sensor that uses the radio wave sensor as a human or human body. To do. Needless to say, the installation location and the arrangement target can also be applied to various locations and various target devices to be detected.

  The output 127 of the radio wave sensor 100 is input to the central control microcomputer 130 of the device in which the radio wave sensor 100 is mounted. As the central control microcomputer 130, a microcomputer, FPGA, or the like can be used.

  The device 130 equipped with the radio wave sensor 100 includes, for example, a hot water washing toilet seat system equipped with the radio wave sensor 100, an automatic teller machine (ATM) equipped with the radio wave sensor 110, and a multifunction printer (MFP). Etc. In the case shown in the figure, the central control computer of the warm water washing toilet seat system equipped with the radio wave sensor 100 controls the toilet seat opening / closing motor, toilet seat lifting / lowering motor, hot water washing water discharge valve, and toilet flushing water discharge valve. Is shown.

  The first modulation signal 104 is generated from the first modulation signal generation means 102. The nth modulation signal 105 different from the first modulation signal 104 is generated from the nth (where n is an integer of 2 or more) modulation signal generation means 103.

  Although FIG. 1 shows only two modulation signal generation units 102 and 103, the number of modulation signal generation units in the present invention is not limited to two. If the modulation signals to be generated are different from each other, the number is larger. It doesn't matter if there are many.

  The modulation signal 104 and the modulation signal 105 are input to the selection unit 106, and one of the modulation signal 104 and the modulation signal 105 is selected by the selection signal 129 from the control unit 128 and is output as the oscillation unit modulation signal 107. The frequencies of radio waves transmitted after modulation, that is, transmission radio frequency and reception radio frequency are 10 GHz (also called X band), 24 GHz (also called K band) and 77 GHz (W band) used in radar. (Also referred to as a frequency band).

  The oscillation means 108 has a function of generating a signal that becomes a transmission radio wave. If the oscillation means 108 is not modulated, that is, when there is no modulation, a signal having a certain frequency is generated. The oscillation means 108 is generally a voltage controlled oscillator (VCO). In this case, voltage signals are used as the modulation signals 104 and 105.

  The oscillation means 108 of the present invention is not limited to a voltage controlled oscillator (VCO). A current controlled oscillator (CCO) or a digitally controlled oscillator (DCO) may be used. Any oscillator that can be modulated is acceptable.

  A signal transmitted from the oscillation means 108 is connected to the antenna 110 via the transmission line 109. As the transmission line 109, a strip line or a coaxial cable provided on the substrate can be used by connecting the oscillation means 108 and the antenna 110. The antenna 110 may be provided with a transmission antenna and a reception antenna separately or may be shared. The antenna 110 in FIG. 1 is a transmission / reception shared antenna.

  A signal that reaches the antenna 110 is emitted from the antenna 110 as a radio wave. An object of the radio wave human sensor 100, that is, a radio wave reflected by the human body returns to the antenna 110 as a received wave and travels on the transmission line 109 toward the oscillating means. On the transmission line 109, a combined wave of a transmission wave and a reception wave exists.

  Since the detection means 111 detects the combined wave of the transmission wave and the reception wave, the frequency component when the transmission wave and the reception wave are not modulated is removed, and has a frequency that is the difference between the frequency of the transmission wave and the frequency of the reception wave. The difference frequency signal 113 is extracted and sent to the filter 115.

  Since the differential frequency signal 113 includes various noise frequency components, the filter 115 removes the frequency component signal that is not related to the movement of the object, that is, noise, and the selected differential frequency signal 113 is amplified. 119 is input.

  The signal 117 from which the noise has been removed becomes an analog signal 121 that has been amplified to an amplitude of several tens to several thousand times by the amplification unit 119, and is input to the AD conversion unit 123.

  The digital signal 124 converted into a digital value by the AD conversion means 123 is sent to the data calculation means 126.

  The data calculation means 126 analyzes and calculates the digital data 124 after AD conversion, and whether the target is moving or stopped, whether the target is approaching or moving away, The movement and state information of the object such as the moving speed and the distance from the antenna to the human body, that is, the detection result 127 is extracted.

  The detection result 127 of the object is sent to the central control microcomputer 130. For example, the oscillation unit 108 is a voltage controlled oscillator (VCO), the modulation signal 104 generated from the modulation signal generation unit 102 is a constant voltage signal, and the modulation signal 105 generated from the modulation signal generation unit 103 is a step. Assume a configuration that is a voltage signal that rises like a step and falls like a step when reaching a certain value.

  In the case of the above configuration, the radio wave human sensor 100 can function as a radio wave Doppler radar that obtains the presence / absence of the movement of the object and the moving speed information of the object during a period in which the selected modulation signal 107 is a constant voltage. The presence / absence / moving speed of the object can be detected.

  Further, during the period when the selected modulation signal 107 rises or falls in a staircase (step) manner, the radio wave human sensor 100 can function as a linear FM standing wave radar, and the radio wave human sensor of the target object. Distance information from the sensor 100 can be detected (see Patent Document 2).

  This radio wave sensor 100 detects the movement of the human body for opening and closing the toilet lid of the warm water flush toilet seat, and the toilet seat for starting / stopping the deodorizing device that operates for a certain period of time after the stool, and for starting and stopping flush water discharge It is assumed that the radio wave human sensor 100 is attached to the warm water washing toilet seat.

For simplicity, it is assumed that the control unit 123 switches alternately at a predetermined time interval of, for example, 100 ms in order to control the modulation signal 104 and the modulation signal 105 of the selection unit 106 in a time-sharing manner.
In this case, a radio wave having a constant frequency is transmitted from the antenna 110 toward the object in the first 100 ms period, and in the next 100 ms period, the frequency rises in a staircase (step) shape, and then falls and returns to the original frequency. Such a radio wave is transmitted from the antenna 110 toward the object.

  In other words, the radio wave human sensor alternately repeats the Doppler radar mode in which the transmission radio frequency is fixed every 100 ms and the linear FM standing wave radar mode in which the transmission radio frequency is increased or decreased in a stepped manner. Will be working.

  In the initial state where no person is in the toilet, the warm water washing toilet seat is waiting for the Doppler radar of the radio wave human sensor 100 to emit a signal detecting the movement of the human body. When a person opens the toilet door, enters the toilet and approaches the toilet, the radio wave transmitted from the antenna 110 is reflected by the person and returned to the antenna 110.

  Therefore, a transmission wave having a certain frequency and a composite wave of a reception wave having a higher frequency exist on the transmission line 109. When a person approaches toward the radio wave sensor 100 mounted on the toilet, the frequency of the received wave increases due to the Doppler effect. When the detection unit 111 detects the synthesized wave, a differential frequency signal 113 having a frequency difference between the transmission wave and the reception wave is obtained. The frequency of the difference frequency signal 113 is approximately proportional to the moving speed of the person. Thereby, when the Doppler radar mode is operating by the control means 128, the operation information of the object indicating whether the object is moving regardless of the moving direction can be obtained.

  Since there is a lower limit and an upper limit on the speed at which a person enters the toilet and heads toward the toilet seat, the frequency of the differential frequency signal 113 also has an upper limit and a lower limit. Since the frequency component deviating from the upper and lower limit frequencies is considered as noise, it is desirable to remove it by the filter 115.

  Since the amplitude of the signal selected by the filter 115 is generally very small, from several tens of μV to several mV, it is amplified by an amplifier, that is, the amplifying means 19 to several tens to several thousand times. The amplified signal is converted into a digital value by the AD conversion means 123 and sent to the data calculation means 126 at the subsequent stage.

  As described above, since the frequency of the difference frequency signal 113 is approximately proportional to the moving speed of the person, the moving speed of the person can be known by analyzing the digital signal 124 after AD conversion to obtain the frequency, but the moving direction is not known. . If the movement speed is within a certain range, it is determined that the movement is a human body, and the detection result that the human body is moving is sent to the central control microcomputer 130 to open the toilet lid. The person sits on the toilet seat after waiting for the toilet lid to rise.

  Next, after the toilet seat is lifted up, the warm water washing toilet seat pays attention to the detection result of the radio frequency sensor 100 in the linear FM standing wave radar mode. When a person is sitting on the toilet seat, the radio wave transmitted from the antenna 110 is reflected by the person sitting on the seat and returns to the antenna 110 as a received wave.

  Therefore, a composite wave of a transmission wave and a reception wave exists on the transmission line 109.

  When the synthesized wave is detected by the detection means 111, a differential frequency signal 113 having a frequency difference between the transmitted wave and the reflected wave is obtained. The differential frequency signal 113 includes distance information between the person and the antenna 100 of the radio wave human sensor 100.

  The difference frequency signal 113 is passed through the filter 115 to remove unnecessary frequency components, further amplified by the amplification means 119 to several tens to several thousand times, converted into digital data by the AD conversion means 123, and input to the data calculation means 126. .

  The data calculation means 126 performs fast Fourier transform (FFT) processing on the input digital signal 124 to convert the frequency axis signal into a time axis signal. From the time axis signal, the human and radio wave human sensor Distance information with 100 is calculated. If the calculated distance is within a predetermined range, for example, 0 cm to 40 cm, it is determined that the person is sitting on the toilet seat, and a detection result that the person is sitting is generated and sent to the central control microcomputer 130. Judging that the person is sitting on the toilet seat, the hot water discharge is permitted, the deodorizing device is stopped, and the toilet flushing water is stopped.

  If the distance between the person and the radio wave sensor 100 is within a certain range, for example, 40 cm to 80 cm, it is determined that the person has stood up from the toilet seat, the hot water spouting is stopped, the operation of the deodorizing device is started, and the toilet flushing water is stopped. Leave.

  Furthermore, when the distance between the person and the radio wave sensor 100 becomes a certain distance, for example, 80 cm or more, it is determined that the person will leave the toilet, the hot water spouting is stopped, and the operation of the deodorizing device is continued. Drain flush water. Thereafter, when a certain period of time has elapsed, the operation of the deodorizing device is stopped, the toilet lid is closed, and a series of operations is completed.

  In the above description, only the Doppler radar is used to detect that a person is approaching the warm water flush toilet seat, and the linear FM standing wave radar is used to detect that a person is seated on the toilet seat. The present invention does not limit the method of use, and the detection results of both may be constantly monitored and the operation of the warm water toilet seat may be determined from the detection results of both.

  In the above description, the Doppler radar and the linear FM type standing wave radar are alternately operated every 100 ms. However, the present invention is not limited to the usage method, and only the Doppler radar is operated at a certain time. The standing wave radar may be stopped, and the Doppler radar may be stopped at a certain time to operate only the linear FM standing wave radar.

Furthermore, you may change dynamically the ratio of the time which both operate | move.
Note that the constituent requirements of the above-described radio wave sensor 100 are not limited to hardware, and may be realized by software (program).

  According to the radio wave human sensor 100 of the present embodiment, when the Doppler radar mode is operated by the control means 128, the object whether or not the object is moving regardless of the moving direction. Operation information is obtained. Furthermore, according to the radio wave human sensor 100, when the linear FM standing wave radar mode is operated by the control means 128, distance information to the object can be obtained.

(Second Embodiment)
FIG. 2 is a block diagram of a warm water washing toilet seat system using the radio wave human sensor 200 according to the second embodiment of the present invention.
The difference between the block diagram of the second embodiment of the present invention in FIG. 2 and the block diagram of the first embodiment of the present invention in FIG. 1 is the number of detection means, differential frequency signals, filters, and amplification means (Amp). Only. The antenna 210 in FIG. 2 is a transmission / reception shared antenna.

  In the first embodiment, there are only one detection means 111, differential frequency signal 113, filter 115, and amplification means 119, but the radio wave motion sensor 200 of the second embodiment has two systems. Therefore, the distance between the first and second detection means 211 and 212 and the antenna 210 is different. This is the only difference between the two, and the description of the portions where the operations of the first embodiment and the second embodiment are the same is omitted, and only the portions where the operations of both are different will be described.

  In the second embodiment, there are two detection means, that is, a first detection means 211 and a second detection means 212. The first detection means 211 is connected at a distance of the transmission line length 1 from the antenna 210, and the second detection means 211 The detection means 212 is connected at a distance of the transmission line length 2 from the antenna 210. Generally, the difference between the lengths of the transmission line length 1 and the transmission line length 2 is that when the oscillation means 208 is not modulated. It is set to approximately 1/8 of the wavelength of the transmission wave.

  If the difference in length between the transmission line length 1 and the transmission line length 2 is approximately 1/8 of the wavelength of the transmission wave, the first detection means 211 compares the phase difference between the transmission wave and the reception wave. The phase difference between the transmission wave and the reception wave received by the second detection means 212 is approximately ¼ of the wavelength of the transmission wave.

In the radio wave sensor 200, the first differential frequency signal 213 output from the first detector 211 is input to the first filter 215, noise is removed, and the first amplifier 219 is input to amplify. The analog signal, which is the first difference frequency signal, is input to the AD conversion unit 223, and the first digital data 224 from the AD conversion unit 223 is input to the data calculation unit 226.
Similarly, the second differential frequency signal 214 output from the second detection means 212 is input to the second filter 216, noise is removed, and the second differential frequency signal 214 is input to the second amplifier 220 to be amplified. The analog signal that is the difference frequency signal is input to the AD conversion means 223, and the second digital data 225 from the AD conversion means 223 is input to the data calculation means 226.
Further, the information 127 processed by the data calculation means 226 is output to the central control microcomputer 230.

  According to the second embodiment, the first modulation signal generation unit 202 generates a fixed voltage, and the nth modulation signal generation unit 203 generates a voltage that rises or falls in a step shape. Assume. When modulation is performed at a fixed voltage, that is, when no modulation is applied, in the Doppler radar mode, in addition to the presence / absence of movement of the object and the movement speed detected in the Doppler mode of the first embodiment, an approach There is an advantage that it is possible to detect the moving direction of whether or not it is separated.

  When an object approaches the antenna 210 in the Doppler radar mode in which the transmission wave is not modulated, the phase of the first differential frequency signal 213 is earlier than the phase of the second differential frequency signal 214. .

  Conversely, when the object moves away from the antenna 210, the phase of the first differential frequency signal 213 is later than the phase of the second differential frequency signal 214.

  Therefore, according to this radio wave sensor 200, if the data calculation means 226 compares the phases of the first differential frequency signal 213 and the second differential frequency signal 214 to determine which is earlier, the object is the radio wave human sensor. Whether the sensor 200 is approaching or moving away can be output as a detection result. As a result, the movement of the human body with respect to the warm water washing toilet seat can be understood in more detail, so the accuracy of the opening / closing operation of the toilet lid, the warming water discharging or stopping operation, the deodorizing device starting or stopping operation, and the toilet flushing water discharging / stopping operation improves. .

(Third embodiment)
FIG. 3 is a block diagram of a warm water washing toilet seat system using a radio wave human sensor 300 according to the third embodiment of the present invention.

  The difference between the radio wave human sensor 300 of the present invention shown in FIG. 3 and the radio wave human sensor 200 of the present invention shown in FIG. 2 is that the antenna is separated into a transmitting antenna 310 and a receiving antenna 328. The only difference is the difference between the transmission wave inputted to the first detection means 311 and the second detection means 312. Since other configurations are the same, description thereof is omitted, and only portions where the operations of both are different will be described.

In the radio wave human sensor 300 of the present invention shown in FIG. 3, the detection means has two of a first detection means 311 and a second detection means 312, and the first detection means 311 has a receiving antenna. A reception wave received by 328 and a transmission wave oscillated by the oscillation means 308 are input.
Further, the received wave received by the receiving antenna 328 and the transmission wave oscillated by the oscillating means 308 are delayed by the delay means 329, that is, the delayed wave of the transmitted wave is input to the second detecting means 312. .

  In general, the delay amount of the delay unit 329 is set to approximately ¼ of the wavelength of the transmission wave when the oscillation unit 308 is not modulated, that is, without modulation. It is assumed that the first modulation signal generation unit 302 generates a fixed voltage and the second modulation signal generation unit 303 generates a voltage that rises or falls in a step shape with such a configuration.

  In the case of a fixed voltage and no modulation, in the Doppler radar mode, in addition to the presence / absence and movement speed of the object detected in the Doppler mode of the first embodiment, it is possible to detect the moving direction of approaching or moving away. Benefits arise.

  In the Doppler radar mode in which the transmission wave is not modulated, when the object approaches the antenna, the phase of the first differential frequency signal 313 is greater than the phase of the second differential frequency signal 314. Get faster. Conversely, when the object moves away from the antennas 310 and 328, the phase of the first differential frequency signal 313 is later than the phase of the second differential frequency signal 314.

  Therefore, according to the radio wave human sensor 300, if the data calculation means 326 compares the phases of the first differential frequency signal 313 and the second differential frequency signal 314 to determine which is earlier, the object is the radio wave human. It can be output as a detection result whether the sensor 300 is approaching or moving away. Thereby, since the movement of the human body with respect to the warm water washing toilet seat can be understood in more detail, the accuracy of the opening / closing operation of the toilet lid, the discharging or stopping operation of the warm water, the starting or stopping operation of the deodorizing device, and the discharging or stopping operation of the toilet flush water . Examples will be described below.

(Configuration of radio wave sensor)
In the radio wave human sensor 100, the oscillation means 108, the transmission / reception shared antenna 110, and the detection means 111, which are components of the radar in each mode, are configured by transmission / reception RFICs. As the transmission / reception RFIC, a Si CMOS integrated circuit or a Si-Ge integrated circuit can be used. First modulation signal generation means 102, second modulation signal generation means 103, selection means 106, data calculation means 126, control means 128, filter 115, amplification means 119, AD conversion means 123, data calculation means 127, etc. It consists of a microcomputer. Specifically, the radio wave sensor 100 has an RFIC (InnoSenT, model SMR-334), a microcomputer (Renesas Electronics, model RX231) and software mounted on a glass epoxy resin substrate (FR-4). ,It is configured. The size of the radio wave human sensor 100 in which the radar frequency is X band (10 GHz) can be realized, for example, with dimensions of about 3 cm × 4 cm × 1 mm. Operation information indicating whether the human body is approaching or moving away from the radio wave sensor 100 and the radio wave sensor 100 from a position approximately 2 m away from the radio wave sensor 100 of the embodiment to the nearest position. The operation that distance information from to the human body can be obtained was confirmed.

  In addition, the said embodiment can be suitably changed within the scope of the present invention. For example, an example of a warm water washing toilet seat system has been described as an apparatus equipped with the radio wave sensor 100, 200, 300, but it is not limited to the warm water washing toilet seat system. An automatic teller machine and a multifunction printer The present invention can also be applied to an apparatus using the radio wave human sensor 100, 200, 300 for detecting a human body as an object. Furthermore, the object of the radio wave sensor of the present invention can be applied not only to a person but also to an animal or a luggage that is a moving object.

100, 200, 300: radio wave sensor (radio wave sensor)
102, 202, 302: 1st modulation signal generation means 103, 203, 303: n (n is an integer of 2 or more) 1st modulation signal generation means 104, 204, 304: 1st modulation signal 105, 205, 305 : N (n is an integer of 2 or more) modulation signal 106, 206, 306: selection means 107, 207, 307: selected modulation signal 108, 208, 308: oscillation means 109, 209, 309: transmission line 110 210: Transmission / reception shared antenna 111: Detection means 113: Difference frequency signal 115: Filter 117: Difference frequency signal 119: Amplification means 121: Analog signal 123: AD conversion means 124: Digital signals 126, 226, 326: Data calculation means 127 227, 327: Information 128, 228, 328 obtained by the data calculation means: control hand 129, 229, 329: selection signals 130, 230, 330: central control microcomputer 211, 311: first detection means 212, 312: second detection means 213, 313: first differential frequency signal 214, 314: first 2 differential frequency signals 215, 315: first filter 216, 316: second filter 217, 317: first differential frequency signal 218, 318 passed through the first filter 2 differential frequency signals 219, 319: first amplifying means 220, 320: second amplifying means 221, 321: amplified first differential frequency signal 222, 322: amplified second differential frequency signal 223 323: AD conversion means 224, 324: first digital data 225, 325: second digital data 328: receiving antenna 3 29: Delay means

Claims (12)

Modulation signal generating means for generating at least two or more modulation signals;
Selecting means for selecting one modulation signal from the modulation signals;
Oscillating means whose oscillation frequency is modulated by a modulation signal generated from the modulation signal generating means;
Control means for switching the selection means in a time-sharing manner;
A transmission antenna for transmitting a signal oscillated by the oscillation means as a transmission radio wave;
Receiving the reflected radio wave reflected by the object and returning as a received radio wave, a receiving antenna provided separately from or shared with the transmitting antenna;
Detecting means connected to a transmission line connecting the oscillating means and at least the transmitting antenna, and for extracting a difference frequency signal of a difference between the frequency of the transmitted radio wave and the frequency of the received radio wave;
A filter that removes unnecessary frequency components from the differential frequency signal output by the detection means;
Amplifying means for amplifying the differential frequency signal selected by the filter;
AD conversion means for converting the differential frequency signal amplified by the amplification means into a digital signal;
A radio wave sensor comprising data calculation means for calculating and analyzing a digital signal output from the AD conversion means. Modulation signal generating means for generating at least two or more modulation signals;
Selecting means for selecting one modulation signal from the modulation signals;
Oscillating means whose oscillation frequency is modulated by a modulation signal generated from the modulation signal generating means;
Control means for switching the selection means in a time-sharing manner;
A transmission antenna for transmitting a signal oscillated by the oscillation means as a transmission radio wave;
Receiving a reflected radio wave returned from an object reflected by an object as a received radio wave, a reception antenna provided separately from or shared with the transmission antenna;
A first difference frequency of a difference between the frequency of the transmission radio wave and the frequency of the reception radio wave is connected to a position of the first signal line length from the reception antenna on a transmission line connecting the oscillation means and the transmission antenna. First detecting means for extracting a signal;
Second detection means connected to a position of a second signal line length from the reception antenna on the transmission line, and for extracting a second difference frequency signal of a difference between the frequency of the transmission radio wave and the frequency of the reception radio wave;
A first filter for removing unnecessary frequency components from the first differential frequency signal output by the first detection means;
A second filter for removing unnecessary frequency components from the second differential frequency signal output by the second detection means;
First amplifying means for amplifying a first differential frequency signal selected by the first filter;
Second amplifying means for amplifying the second differential frequency signal selected by the second filter;
AD conversion means for converting the first differential frequency signal amplified by the first amplification means and the second differential frequency signal amplified by the second amplification means into digital values;
Data computing means for computing and analyzing the digital signal output by the AD converting means;
A radio wave sensor consisting of Modulation signal generating means for generating at least two or more modulation signals;
Selecting means for selecting one modulation signal from the modulation signals;
Oscillating means whose oscillation frequency is modulated by a modulation signal generated from the modulation signal generating means;
Control means for switching the selection means to time division;
A transmission antenna for transmitting a signal oscillated by the oscillation means as a transmission radio wave;
Receiving a reflected radio wave returned from an object reflected by an object as a received radio wave, a receiving antenna provided separately from the transmitting antenna;
Delay means for delaying a signal output from the oscillating means;
A reception wave received from the reception antenna and a transmission wave output from the oscillating means are input, and a first differential frequency signal having a frequency difference corresponding to a difference between the frequency of the transmission wave and the frequency of the reception wave. First detecting means for taking out
Delay means for delaying a signal output from the oscillating means;
A reception wave received from the reception antenna and a signal obtained by delaying the transmission wave output from the oscillation means by the delay means are input, and a second difference between the frequency of the transmission wave and the frequency of the reception wave is input. A second detection means for extracting a differential frequency signal;
A first filter for removing unnecessary frequency components from the first differential frequency signal output by the first detection means;
A second filter for removing unnecessary frequency components from the second differential frequency signal output by the second detection means;
First amplifying means for amplifying a first differential frequency signal selected by the first filter;
Second amplifying means for amplifying the two differential frequency signals selected by the second filter;
AD conversion means for converting the first differential frequency signal amplified by the first amplification means and the second differential frequency signal amplified by the second amplification means into digital values;
Data computing means for computing and analyzing the digital signal output by the AD converting means;
A radio wave sensor consisting of   The radio wave sensor according to claim 2, wherein a distance between the first detection unit and the second detection unit is a distance corresponding to 1/8 wavelength of a transmission radio wave when there is no modulation.   The radio wave sensor according to claim 3, wherein the delay amount of the delay unit corresponds to a quarter wavelength of an unmodulated signal output from the oscillation unit.   The plurality of modulation signals include at least two of a transmission radio frequency after modulation having a constant value, a stepwise increase or decrease, and a continuous increase or decrease. Radio wave sensor described in Crab.   The radio wave sensor according to any one of claims 1 to 5, wherein the frequency of the transmission radio wave is any one of 10 GHz, 24 GHz, and 77 GHz.   The information processed by the data calculation means includes the operation information of the object whether the object is moving regardless of the moving direction and the distance information from the transmitting antenna to the object. The radio wave sensor according to claim 1, wherein the radio wave sensor is provided.   The information processed by the data calculation means includes the operation information of the object whether the object is approaching or moving away from the antenna and the distance information from the transmitting antenna to the object. The radio wave sensor according to claim 2, wherein the radio wave sensor is provided.   The processing method processed by the data calculation means includes at least two of a radio wave Doppler radar method, a radio wave FMCW radar method, a radio wave FM linear type standing wave method, and a radio wave pulse compression radar method. Radio wave sensor in any one.   An apparatus equipped with the radio wave sensor, comprising the radio wave sensor according to claim 1.   The apparatus equipped with the radio wave sensor according to claim 11, wherein the apparatus equipped with the radio wave sensor is any one of a warm water washing toilet seat system, an automatic teller machine and a multifunction printer.

Images