JP2008180688A - High-frequency sensor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-frequency sensor device capable of detecting a detection object more surely and quickly. <P>SOLUTION: A Doppler signal included in a reception wave is examined by scanning a main beam output from an antenna in a plurality of different directions sequentially. When a Doppler signal from a direction wherein a radio wave is radiated for the first time by one-time scanning in the plurality of directions exceeds a threshold set beforehand, existence of the detection object is determined based on the Doppler signal. When the Doppler signal from the direction wherein the radio wave is radiated for the first time by one-time scanning does not exceed the threshold set beforehand, and a Doppler signal from a direction wherein the radio wave is radiated in the second time or after exceeds the threshold set beforehand, existence of the detection object is determined based on Doppler signals acquired by the scanning and next-time scanning. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a high frequency sensor device.

  When a microwave hits the human body, a reflected wave or a transmitted wave is generated. A high-frequency sensor device that receives this reflected wave or transmitted wave and detects the presence or absence of a human body can be used for automatic doors, remote control of equipment, toilet cleaning devices, and the like. Furthermore, there is a high-frequency sensor device that detects a moving object, which is useful for automatic washing of a flush toilet, for example.

  In order to detect a moving object including a human body, the Doppler effect can be used. That is, when radio waves or sound waves are reflected by a moving object, the frequency of the reflected waves is Doppler shifted. A moving object is detected by obtaining a difference frequency spectrum between the reflected wave and the transmitted wave. Furthermore, since the Doppler frequency is proportional to the moving speed of the object, the moving speed can also be known.

  When a radio wave is used as a transmission wave, it is important to accurately control the direction of radio wave radiation from the antenna constituting the sensor toward the object. In an antenna in which the feed element and the parasitic element surrounding it are configured with patch electrodes and electrically scanned by a high-frequency switch, the control line provided to switch the high-frequency switch on and off affects the grounding characteristics of the antenna. And may make it difficult to accurately control the radiation direction of the radio wave beam.

There is a technology disclosure example regarding a microstrip antenna in which a parasitic element is connected to a high-frequency switch provided on the back surface of a substrate through a through-hole type control line in the substrate and the radiation direction of a radio wave beam is switched, and a high-frequency sensor using the same Yes (Patent Document 1).
International Publication Number WO2006 / 035881A1

  However, it is not easy to limit the radiation direction of the radio wave beam to a predetermined direction. That is, when radio waves are radiated from an antenna, side lobes (unnecessary radio waves) radiated in a direction different from the main beam radiated in a target direction often occur. For this reason, for example, when trying to detect from which direction the human body approaches the high-frequency sensor device, it is possible to determine whether the detection is performed by the main beam or the side lobe. It could be difficult.

  In addition, when the position of the detected object is specified by sequentially scanning a plurality of directions, the detected object can be detected more quickly if the scanning step can be appropriately skipped according to the influence of the side lobe, the moving direction of the detected object, etc. It becomes possible to specify the position of.

  The present invention has been made based on the recognition of such a problem, and provides a high-frequency sensor device that can detect a detected object more reliably and quickly.

  According to one aspect of the present invention, an oscillation circuit that generates a transmission wave, an antenna that radiates the transmission wave and receives a reflected wave from the object of the transmission wave as a reception wave, and a detection circuit that detects the reception wave A control determination circuit for determining the presence / absence of detection of the detected object based on a Doppler signal included in the detection circuit, and a radio wave for outputting a control signal for changing the direction of the radio wave radiated from the antenna to the antenna A scanning control circuit, wherein the control determination circuit sequentially scans a main beam output from the antenna in a plurality of different directions according to a control signal from the radio wave scanning control circuit, and is included in the received wave. If the Doppler signal from the direction in which radio waves are first emitted in a single scan in the plurality of directions exceeds a preset threshold value Determines the presence or absence of an object to be detected based on the Doppler signal, and the Doppler signal from the direction in which the radio wave is radiated first in the one scan does not exceed a preset threshold value and the second and later. When the Doppler signal from the direction in which the radio wave is emitted exceeds a preset threshold, the presence or absence of a detection object is determined based on the Doppler signal obtained in that scan and the next scan. A sensor device is provided.

  The present invention provides a high-frequency sensor device that can detect a detected object more reliably and quickly.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram of a high-frequency sensor device according to an embodiment of the present invention.
The high frequency sensor device includes a high frequency unit 10 and a control unit 20. The high-frequency unit 10 includes an antenna 100 including a feeding element 102 and parasitic elements 104 and 106, and a high-frequency circuit 12. The high-frequency circuit 12 is provided with an oscillation circuit 14 that generates a transmission wave and a detection circuit 16 that extracts a Doppler signal from the reception wave.

  The transmission wave radiated from the antenna 100 hits an object such as a human body to generate a reflected wave, and is received by the feed element 102. The antenna 100 may be used for both transmission and reception, or transmission and reception may be separated. The frequencies of transmission waves that can be used in the high-frequency sensor device for human body detection are 10.525 and 24.15 GHz.

In the case of a moving object, a Doppler signal is output from the detection circuit 16 of the high frequency unit 10. This Doppler signal is input to the control determination circuit 26 via the amplifier 22 of the control unit 20. The other output of the amplifier 22 is input to the control determination circuit 26 via the comparator 24. The output is input to the load control circuit 30 and the radio wave scanning control circuit 32. The radio wave scanning control circuit 32 outputs a control signal for changing the radiation direction of the radio wave beam of the parasitic elements 104 and 106 according to the signal from the control determination circuit 26.
FIG. 2 is a plan view illustrating an example of a microstrip antenna provided in the high-frequency sensor device of the present embodiment.
FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2 and the subsequent drawings, the same elements as those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description thereof will be omitted as appropriate.

  This antenna has a structure in which three antenna elements 102, 104, and 106 made of a rectangular conductive thin film are arranged in a straight line on the front surface of a substrate 101 made of an insulating material such as ceramics or resin. The central antenna element 102 is a feeding element that receives a supply of microwave power directly from a microwave signal source (that is, through an electric wire). The two antenna elements 104 and 106 provided on both sides of the feeding element 102 are parasitic elements that do not receive direct feeding. The excitation direction of the feed element 102 is the vertical direction in FIG. 2, and the arrangement direction of the three antenna elements 104, 102, 106 is a direction orthogonal to the excitation direction. In this embodiment, as an example, the left and right parasitic elements 104 and 106 are arranged at the position of the line object around the central feeding element 102, that is, at the same distance from the feeding element 102, and the size is also the same. Yes. The sizes of the parasitic elements 104 and 106 can be substantially the same as the size of the feeder element 102, but may be different. The length in the excitation direction has an optimum range depending on the wavelength of the microwave to be used, so the range that can be changed is narrow, but the length in the direction perpendicular to the excitation direction is changed in a wider range. be able to.

  One end of the power supply line 108 is connected to a predetermined position (hereinafter referred to as “power supply point”) on the back surface of the power supply element 102. As shown in FIG. 3, the power supply line 108 is a conductive line that penetrates the substrate 101, and the other end of the power supply line 108 is connected to the microwave output terminal of the high-frequency circuit 12 positioned on the back surface of the substrate 101. Has been. The high frequency circuit 12 can be formed as a one-chip IC, for example. The power feeding element 102 receives microwave power of a specific frequency (for example, 10.525 GHz, 24.15 GHz, or 76 GHz) output from an oscillation circuit 14 (see FIG. 1) provided in the high frequency circuit 12 at a feeding point. Excited.

  As shown in FIG. 3, the substrate 101 is a multilayer substrate, and a thin-film ground electrode 116 is provided as a single layer over the entire surface of the substrate 101. The ground electrode 116 is connected to the ground terminal of the high-frequency circuit 12 through the ground line 115.

  As shown in FIGS. 2 and 3, one end of each of the control lines 110 and 112 is also connected to a predetermined portion (hereinafter referred to as “grounding point”) on the back surface of each of the parasitic elements 104 and 106. The other ends of the control lines 110 and 112 are respectively connected to one side terminals of the switches 120 and 124 disposed on the back surface of the substrate 101. The other terminals of the switches 120 and 124 are connected to the ground electrode 116 via ground lines 118 and 122, respectively. The switches 120 and 124 can be individually turned on / off. By turning on and off the left switch 120, whether the left parasitic element 104 is connected to the ground electrode 116 or in a floating state is switched. The on / off operation of the right switch 124 switches whether the right parasitic element 106 is connected to the ground electrode 116 or enters a floating state.

  The switches 120 and 124 are preferably high-frequency switches, but it is not particularly necessary that the impedance with respect to the microwave frequency to be used is adjusted to a predetermined appropriate value, and the off characteristics (isolation) of the switches that block high-frequency signals. ) Is good. As shown in FIG. 2, the position of the feeding point of the feeding element 102 is, for example, an optimum antenna corresponding to the wavelength λg of the microwave to be used on the substrate 101 in the excitation direction (vertical direction) of the feeding element 102. A direction (left-right direction) that is a position that is separated from the lower edge (or upper edge) of the feed element 102 by the length (substantially λg) upward (or lower) and orthogonal to the excitation direction (vertical direction) The center position of the feed element 102 is shown in FIG. On the other hand, the positions of the grounding points of the parasitic elements 104 and 106 are, for example, outside the range of the width L / 2 with the center of the parasitic elements 104 and 106 as the center in the excitation direction (vertical direction). The position is the center position of the parasitic elements 104 and 106 in the orthogonal direction (left-right direction). Here, L is a length in the excitation direction of the parasitic elements 104 and 106.

  In the microstrip antenna configured as described above, the switches 120 and 124 are operated to switch whether the parasitic elements 104 and 106 are connected (grounded) to the ground electrode 116, thereby outputting from the microstrip antenna. The radiation direction of the radio wave beam can be switched to one of a plurality of directions. Since the radiation direction is determined by the positional relationship between the feed element 102 and the parasitic elements 104 and 106, the feed element 102 and the high-frequency circuit 12 can be connected via the feed line 108 that is extremely shorter than the wavelength. Therefore, the transmission loss is low and the efficiency is good. Further, since the radiation direction of the radio wave beam can be changed with a single switch connected to the control line, this microstrip antenna is suitable for reducing the substrate size and manufacturing costs.

FIG. 4 is a schematic diagram showing a change in the radiation direction of the radio wave beam due to the operation of the switches 120 and 124.
In FIG. 4, the ellipse schematically represents the radiated radio wave beam, and the angle on the horizontal axis represents the angle (radiation angle) of the radio wave radiation direction viewed from the direction perpendicular to the main surface of the substrate 101. 2 represents that the radiation direction is tilted to the right in FIG. 2, and a negative angle represents tilt to the left.

  As shown in FIG. 4, when both switches 120 and 124 are on (that is, when both parasitic elements 104 and 106 are grounded), the radio wave beam of the substrate 101 is expressed as indicated by a dotted line. Radiated in a direction perpendicular to the main surface. Even when both switches 120 and 124 are off (that is, when both parasitic elements 104 and 106 are in a floating state), the radio wave beam is perpendicular to the main surface of the substrate 101 as indicated by a one-dot chain line. Radiated in the direction.

On the other hand, when the left switch 120 is on and the right switch 124 is off (that is, when only the left parasitic element 104 is grounded), the radio wave beam is on the left side (depending on conditions). Is emitted in the direction tilted to the right). In addition, when the left switch 120 is off and the right switch 124 is on (that is, when only the right parasitic element 106 is grounded), the radio beam is on the right side as shown by another broken line. Radiated in a direction tilted to the left (depending on conditions).
Thus, the radiation direction of the radio wave beam can be changed by selecting the parasitic elements 104 and 106 to be grounded.

  However, when the radiation direction of the radio wave beam is changed in this way, a side lobe (unnecessary radio wave) radiated in a direction different from the main beam radiated in the target direction often occurs. When the main beam is radiated at a wider angle, the side lobe tends to be larger. For this reason, for example, when detecting from which direction the human body is approaching the high-frequency sensor device, it is possible to determine whether it is detected by the main beam or by the side lobe. It can be difficult.

FIG. 5 is a schematic diagram for explaining the generation of side lobes.
For example, as illustrated in FIG. 5A, when only the switch 124 is on and the parasitic element 106 is grounded, side lobes may be emitted in a direction different from the main beam 202. Similarly, as illustrated in FIG. 5B, when only the switch 120 is on and the parasitic element 104 is grounded, the side lobe 208 may be radiated in a direction different from the main beam 206. is there.

  For example, when the detected object 900 is approaching the antenna 100 from the direction shown in FIGS. 5A and 5B, the Doppler is shown by the main beam 206 as shown in FIG. A signal is detected, but at the same time, a Doppler signal may be detected by the side lobe 204 as shown in FIG. In other words, when the object to be detected is detected by scanning the radio waves to the left and right, the Doppler signal is generated even if the main beam is emitted in either the left or right direction, making it difficult to specify the position of the object to be detected. This is particularly noticeable when only a change in the frequency included in the Doppler signal is detected, and it is difficult to determine whether the detection is based on the main beam or the side lobe.

On the other hand, in the present embodiment, the detection is continuously performed twice as necessary by the determination of the control determination circuit 26, and the position of the detection target is specified based on the result.
FIG. 6 is a graph for explaining a detection method executed in the high-frequency sensor device of the present embodiment.
That is, the switch (SW1) 120 and the switch (SW2) 124 respectively connected to the parasitic elements 104 and 106 are alternately turned on, and the radiation state of the radio wave beam is illustrated as illustrated in FIGS. 5 (a) and 5 (b). Switch. And the Doppler signal corresponding to each radiation state is detected. The Doppler signal includes the movement of the detected object as a change in frequency. In the specific example shown in FIG. 6, the Doppler signal of the detection object 900 is detected in the periods d1 and d1 ′ in which SW1 is on and the periods d2 and d2 ′ in which SW2 is on. These periods d1, d2, d1 ′, d2 ′ can be set to about 25 to 50 milliseconds, for example.
In such a Doppler signal, as shown in FIG. 7, a predetermined threshold value is set, and when the Doppler signal does not exceed these threshold values, it is determined as “non-detection”, and when it exceeds, it is determined as “detection”.

FIG. 8 and FIG. 9 are tables showing a method for specifying a detection target based on such a determination criterion.
10 and 11 are graphs illustrating the waveform of the Doppler signal.

First, as shown in FIG. 8 and FIG. 10A, when no Doppler signal is detected in both the period d1 and the period d2 (d1 = 0, d2 = 0), it is determined as non-detection. To do.
On the other hand, as shown in FIG. 8 and FIG. 10B, when the Doppler signal is detected in the period d1 and not detected in the period d2, that is, when the Doppler signal is not detected (d1 = 1, d2 = 0), When the switch SW1 is turned on, it is determined that the detection is performed, that is, the detection is performed by the main beam 206 shown in FIG. 5B, and as shown in FIG. Determine that it is moving.

  Next, as shown in FIG. 8, when Doppler signals are detected in both the period d1 and the period d2 (d1 = 1, d2 = 1), the amplitudes of those Doppler signals are compared. As shown in FIG. 10C, when the amplitude of the Doppler signal in the period d1 is larger than the amplitude of the Doppler signal in the period d2 (d1> d2), detection is performed when SW1 is turned on, that is, It is determined that the main beam 206 shown in FIG. 5B and the side lobe 204 shown in FIG. 5A are detected, and as shown in FIG. Determine that it is moving.

  On the contrary, as shown in FIG. 10D, when the amplitude of the Doppler signal in the period d2 is larger than the amplitude of the Doppler signal in the period d1 (d2> d1), SW2 is turned on. Detection, that is, it is determined that the main beam 202 shown in FIG. 5A and the side lobe 208 shown in FIG. 5B are detected, respectively. It is determined that the detection body 900 is moving.

Next, as shown in FIG. 8, when the Doppler signal is not detected in the period d1 and is detected in the period d2 (d1 = 0, d2 = 1), the result of the next scan is also taken into consideration. judge.
FIG. 9 is a table showing a method of determination based on the result of the second scan.
First, as shown in FIG. 10E, when the Doppler signal is not detected in both the periods d1 ′ and d2 ′ following the periods d1 and d2 (d1 ′ = 0, d2 ′ = 0). , It is determined that the main beam 202 has been detected when SW2 is on. In other words, contrary to that shown in FIG. 5A, it is determined that the detected object 900 has moved on the right side from the antenna 100. At this time, since the speed of the detection object 900 was high, it can be estimated that the movement has already been completed within the detection range of the antenna 100 in the periods d1 ′ and d2 ′. For example, a case where the detected object 900 approaches the antenna 100 from the right side toward the antenna 100 at a high speed and stops in front of the antenna 100 can be cited. In addition, for example, there is a case where the detected object 900 stationary in front of the antenna 100 swings his left hand from left to right in front of the antenna 100. In this embodiment, since it can determine with detection also in these situations, the high frequency sensor apparatus excellent in responsiveness can be provided.

  Next, when the Doppler signal is detected in the period d1 ′ and not detected in the period d2 ′ (d1 ′ = 1, d2 ′ = 0), the amplitudes of the Doppler signals in the period d2 and the period d1 ′ are compared. To do. As shown in FIG. 10F, when the amplitude of the Doppler signal in the period d2 is larger than the amplitude of the Doppler signal in the period d1 ′ (d2> d1 ′), the detection is performed when the SW2 is turned on. That is, it is determined that detection is performed by the main beam 202 shown in FIG. 5A and the side lobe 208 shown in FIG. 5B, respectively. Is determined to be moving.

  On the contrary, as shown in FIG. 11A, when the amplitude of the Doppler signal in the period d1 ′ is larger than the amplitude of the Doppler signal in the period d2 (d1 ′> d2), SW1 is set. When it is turned on, it is determined that the detection is made by the main beam 206 shown in FIG. 5B and the side lobe 204 shown in FIG. 5A, respectively, and as shown in FIG. It is determined that the detected object 900 is moving on the left side.

  On the other hand, as shown in FIG. 11B, when the Doppler signal is not detected in the period d1 ′ and detected in the period d2 ′ (d1 ′ = 0, d2 ′ = 1), it is continued twice. Since the detection is performed only when the switch SW2 is turned on, it is determined that the detection is performed only by the main beam 202, and the detected object 900 moves on the right side from the antenna 100, contrary to FIG. It is determined that

  On the other hand, when a Doppler signal is detected in both the period d1 'and the period d2' (d1 '= 1, d2' = 1), the amplitudes of the respective Doppler signals are compared. Then, as shown in FIG. 11C, when the amplitude of the Doppler signal in the period d2 is larger than the amplitude of the Doppler signal in the periods d1 ′ and d2 ′ (d2> d1 ′, d2> d2 ′). , When SW2 is turned on during the period d2, it is determined that the detection is the strongest, that is, the main beam 202 shown in FIG. 5A and the side lobe 208 shown in FIG. Conversely, it is determined that the detection object 900 is moving on the right side from the antenna 100.

  Further, as shown in FIG. 11D, when the amplitude of the Doppler signal in the period d1 ′ is larger than the amplitude of the Doppler signal in the periods d2 and d2 ′ (d1 ′> d2, d1 ′> d2 ′). Is detected most strongly when SW1 is turned on in the period d1 ′, that is, it is determined that detection is performed by the main beam 206 shown in FIG. 5B and the side lobe 204 shown in FIG. It is determined that the detected object 900 is moving on the left side from the antenna 100 as shown in FIG.

  As shown in FIG. 11E, when the amplitude of the Doppler signal in the period d2 ′ is larger than the amplitude of the Doppler signal in the periods d2 and d1 ′ (d2 ′> d2, d2 ′> d1 ′). Is determined to be strongest when SW2 is turned on in the period d2 ′, that is, detected by the main beam 202 shown in FIG. 5A and the side lobe 208 shown in FIG. 5B. On the contrary, it is determined that the detected object 900 is moving on the right side from the antenna 100.

  As described above, in the present embodiment, when the object to be detected includes the first direction and the object to be detected is detected, the position of the object to be detected is specified based only on the result of the first scan. In addition, when the object to be detected is detected in the second or later direction in which the radio waves are scanned, the position of the object to be detected is specified based on the result of the second scan, so that the object to be detected such as a human body Regardless of the direction or speed of approaching to the antenna 100, the position of the detection target can be accurately identified, and detection with excellent responsiveness can be performed. Further, since the influence of the side lobe can be removed, the scan speed, that is, the switching speed of the radio wave radiation direction can be slowed, and a relatively slow operation can be detected.

  By the way, in the high frequency sensor device of the present embodiment, switching noise may occur when the direction of radio wave radiation is switched. In such a case, if the detection determination of the detection target is performed without considering the generation time of the switching noise, erroneous detection is caused. Therefore, in such a case, instead of making a detection decision based on the Doppler signal from the moment when the radiation direction of the radio wave is switched, the detection decision is made in consideration of the generation time of the switching noise. A waiting time should be provided. That is, the timing (speed) at which the radio wave radiation direction is switched is determined by the waiting time until detection determination and the time required for detection detection of the detected object. The time required for detection detection of the detection target is preferably 1 to 50 milliseconds in consideration of the movement speed of the human body and hand. For example, if set to 10 milliseconds, 50 Hz (= half cycle 10) The human body and hand can be detected accurately with respect to movements of milliseconds or longer.

Next, a case where scanning is sequentially performed in three directions will be described.
FIG. 12 is a schematic view illustrating the radiation direction of the main beam.
For example, in the antenna 100 described above with reference to FIGS. 2 and 3, as described above with reference to FIG. 4, as described above with reference to FIG. Further, the state in which the main beam is radiated in the direction perpendicular to the main surface of the substrate 101 can be sequentially repeated. For example, as shown in FIG. 12, these three states can be sequentially switched as periods d1, d2, and d3.
Even in such a case, according to the present embodiment, the determination can be made in consideration of the result of the second scan as necessary.

FIG. 13 to FIG. 19 are tables showing the determination method when sequentially scanning in three directions.
First, as illustrated in FIG. 13, when the Doppler signal is not detected in any of the periods d <b> 1 to d <b> 3, it is determined that the detection target is not detected.
Further, when the Doppler signal is detected in the period d1 and is not detected in any of the periods d2 and d3, it is determined that the detected object is detected in the direction detected in the period d1.

Next, as shown in FIG. 14A, in the case of non-detection in the period d1, detection in the period d2, and non-detection in the period d3, the determination is made in consideration of the result of the next scan. Then, as shown in FIG. 14B, in this case, measurement in the direction (period d3 ′) corresponding to the period d3 is skipped in the next scan.
This means that during scanning in the order of period d 1 → d 2 → d 3 → d 1..., It was detected in period d 2 and not detected in periods d 1 and d 3, as illustrated in FIG. This is because the detection object 900 has a high probability of moving in the direction opposite to the scanning direction, that is, in the direction from d2 to d1. If the detected object 900 is moving in the same direction as the scan direction, the probability of being detected not only in the period d2 but also in the period d1 and the period d3 is high. That is, when scanning is performed in the order of the period d 1 → d 2 → d 3 → d 1..., The detection in the period d 2 and the non-detection in the periods d 1 and d 3 indicate that the detected object 900 is in the scan direction. Is likely to move in the opposite direction, and in the next scan, the detection object is unlikely to exist in the direction of the period d3, and is likely to move in the direction of the period d1.

  As described above, when the detection is performed only in the period d2, the period d3 'can be skipped during the next scan, and the scan can be performed only in the period d1' and the period d2 '. If no detection is performed in both the period d1 'and the period d2' in the second scan (WJ0), it is determined that the detection is performed in the period d2.

  On the other hand, when the second scan is detected in the period d1 'and not detected in the period d2' (WJ1a, WJ1b), the amplitudes of the Doppler signal in the period d2 and the Doppler signal in the period d1 'are compared. If the Doppler signal in period d2 is larger, it is determined that the signal is detected in period d2 (WJ1a). If the Doppler signal in period d1 ′ is larger, it is determined that the signal is detected in period d1 ′ (WJ1b). ).

  On the other hand, if the second scan is not detected in the period d1 'and is detected in the period d2' (WJ2), it is determined that the detection is performed in the periods d2 and d2 '.

  On the other hand, when detection is performed in the period d1 'or the period d2' in the second scan (WJ3a, WJ3b, WJ3c), the Doppler signal in the period d2 is compared with the amplitude of the Doppler signal in the periods d1 'and d2'. Then, when the Doppler signal in the period d2 is the largest, it is determined that the signal is detected in the period d2 (WJ3a), and when the Doppler signal in the period d1 ′ is the largest, it is determined that the signal is detected in the period d1 ′. (WJ3b) When the Doppler signal in the period d2 ′ is the largest, it is determined that the detection is performed in the period d2 ′ (WJ3c).

  Next, as shown in FIG. 15, when the detection is performed in the period d1 and the period d2, the amplitudes of these Doppler signals are compared. If the Doppler signal in the period d1 is larger, it is determined that the signal is detected in the period d1 (SJ3a). If the Doppler signal in the period d2 is larger, it is determined that the signal is detected in the period d2 (SJ1b).

Next, as shown in FIG. 16A, when the detection is performed only in the period d3, the determination is made in consideration of the result of the next scan. In this case, at the time of the next scan, there is a high possibility that the detection object is present at any of the positions corresponding to d1 to d3, so the scan is executed without skipping any detection.
If it is not detected in any of the periods d1 ′, d2 ′, and d3 ′ in the next scan, it is determined that the detection is performed in the period d3 (WJ0).
In addition, when the detection is performed in the period d1 ′ in the next scan and is not detected in the periods d2 ′ and d3 ′, the amplitudes of these Doppler signals are compared. If the Doppler signal in period d3 is larger, it is determined that the signal is detected in period d3 (WJ1a). If the Doppler signal in period d1 ′ is larger, it is determined that the signal is detected in period d1 ′ (WJ1b). ).

  Further, when the detection is performed in the period d2 'in the next scan and in the period d1' and d3 'is not detected, the amplitudes of these Doppler signals are compared. If the Doppler signal in period d3 is larger, it is determined that the signal is detected in period d3 (WJ2a). If the Doppler signal in period d2 ′ is larger, it is determined that the signal is detected in period d1 ′ (WJ2b). ).

In the next scan, detection is performed in the period d1 ′ and the period d2 ′, and in the period d3 ′, when the detection is not performed, the amplitudes of these Doppler signals are compared. When the Doppler signal in the period d3 is the largest, it is determined that the signal is detected in the period d3 (WJ3a). When the Doppler signal in the period d1 ′ is the largest, it is determined that the signal is detected in the period d1 ′ (WJ3b). ), When the Doppler signal in the period d2 ′ is the largest, it is determined that the detection is performed in the period d2 ′ (WJ3c).
On the other hand, when the next scan is detected only in the period d3 ′, it is determined that the detection is performed in the periods d3 and d3 ′ (WJ4).

  Further, in the next scan, detection is performed during the period d1 'and the period d3', and when the detection is not performed during the period d2 ', the amplitudes of these Doppler signals are compared. When the Doppler signal in the period d3 is the largest, it is determined that the detection is performed in the period d3 (WJ5a). When the Doppler signal in the period d1 ′ is the largest, it is determined that the detection is performed in the period d1 ′ (WJ5b). ), When the Doppler signal in the period d3 ′ is the largest, it is determined that the detection is performed in the period d3 ′ (WJ5c).

  Similarly, the amplitudes of these Doppler signals are compared even when the detection is performed in the period d2 'and the period d3' in the next scan and in the case of no detection in the period d1 '. When the Doppler signal in the period d3 is the largest, it is determined that the detection is performed in the period d3 (WJ6a). When the Doppler signal in the period d2 ′ is the largest, it is determined that the detection is performed in the period d2 ′ (WJ6b). ), When the Doppler signal in the period d3 ′ is the largest, it is determined that the detection is performed in the period d3 ′ (WJ6c).

  On the other hand, when the detection is performed in both the periods d1 'and d2'd3' in the next scan, the amplitudes of these Doppler signals are compared. When the Doppler signal in the period d3 is the largest, it is determined that the detection is performed in the period d3 (WJ7a). When the Doppler signal in the period d1 ′ is the largest, it is determined that the detection is performed in the period d1 ′ (WJ7b). ) When the Doppler signal in period d2 ′ is the largest, it is determined that the detection is performed in period d2 ′ (WJ7c). When the Doppler signal in period d3 ′ is the largest, it is determined that the detection is performed in period d3 ′. (WJ7d).

  Next, as shown in FIG. 17, when the detection is performed during the period d1 and the period d3 and when the detection is not performed during the period d2, the amplitudes of these Doppler signals are compared. If the Doppler signal in the period d1 is larger, it is determined that the signal is detected in the period d1 (SJ5a). If the Doppler signal in the period d3 is larger, it is determined that the signal is detected in the period d3 (SJ5b). This corresponds to, for example, a case where the detected object moves at a high speed in the same direction as the scanning direction. In such a case, if the determination is made as shown in FIG. 17, the approach direction of the detection object moving at a high speed can be reliably detected.

  Next, as shown in FIG. 18A, when the period d1 is not detected in the period d1, the period d2 and the period d3 are detected, and the Doppler signal in the period d2 is larger than the Doppler signal in the period d3. The determination is made in consideration of the result of the next scan. In this case, there is a high possibility that the detection in the period d3 is caused by the influence of the side lobe, and there is a high probability that the moving direction of the detection object is opposite to the scanning direction. That is, at the time of the next scan, there is a low possibility that the detection target is in a position corresponding to the period d3, and there is a high possibility that the detection is performed in the period d2 ′ or the period d1 ′. A scan can be performed.

Then, as shown in FIG. 18B, if no detection is performed in either of the periods d2 ′ and d3 ′ in the next scan, it is determined that the detection is performed in the period d2 (WJ0).
Further, when the detection is performed in the period d1 ′ in the next scan and not detected in the period d2 ′, the amplitudes of these Doppler signals are compared. If the Doppler signal in period d2 is larger, it is determined that the signal is detected in period d2 (WJ1a). If the Doppler signal in period d1 ′ is larger, it is determined that the signal is detected in period d1 ′ (WJ1b). ).

  If the detection is performed in the period d2 'in the next scan and is not detected in the period d1', it is determined that the detection is performed in the periods d2 and d2 '(WJ2).

  Further, when the next scan detects in both the period d1 'and the period d2', the amplitudes of these Doppler signals are compared. When the Doppler signal in the period d2 is the largest, it is determined that the detection is performed in the period d2 (WJ3a). When the Doppler signal in the period d1 ′ is the largest, it is determined that the detection is performed in the period d1 ′ (WJ3b). ), When the Doppler signal in the period d2 ′ is the largest, it is determined that the detection is performed in the period d2 ′ (WJ3c).

  Similarly, as shown in FIG. 19A, when detection is not performed in the period d1, detection is performed in the period d2 and the period d3, and the Doppler signal in the period d3 is larger than the Doppler signal in the period d2, The result of the next scan is also taken into consideration for determination. At this time, the scan can be executed while skipping the period d2 '.

  In the first scan, the Doppler signal is larger in the period d3 than in the period d2, which means that there is a person where the radio wave emission range in the period d2 and the radio wave emission range in the period d3 overlap. In other words, it means that there is a person on the radiation range side of the radio wave in the period d3. For example, if the radio wave emission range is −25 ° to + 25 ° in the period d2 (based on the 3 dB down beam width) and the radio wave emission range is +0 to + 50 ° in the period d3, there is a person around + 20 °. Will do. Accordingly, if the period d2 ′ is skipped in the second scan and the periods d1 ′ and d3 ′ are scanned, the influence of the radio wave scanning order and side lobes can be eliminated, and the position of the detected object can be accurately identified, and the response Detection with excellent properties becomes possible.

Then, as shown in FIG. 19B, when no detection is performed in both the periods d1 ′ and d3 ′ in the next scan, it is determined that the detection is performed in the period d3 (WJ0).
Further, when the detection is performed in the period d1 ′ in the next scan and is not detected in the period d3 ′, the amplitudes of these Doppler signals are compared. If the Doppler signal in period d3 is larger, it is determined that the signal is detected in period d3 (WJ1a). If the Doppler signal in period d1 ′ is larger, it is determined that the signal is detected in period d1 ′ (WJ1b). ).

  If the detection is performed in the period d3 'in the next scan and is not detected in the period d1', it is determined that the detection is performed in the periods d3 and d3 '(WJ4).

  Further, when the next scan detects in both the period d1 'and the period d3', the amplitudes of these Doppler signals are compared. When the Doppler signal in the period d3 is the largest, it is determined that the detection is performed in the period d3 (WJ5a). When the Doppler signal in the period d1 ′ is the largest, it is determined that the detection is performed in the period d1 ′ (WJ5b). ), When the Doppler signal in the period d3 ′ is the largest, it is determined that the detection is performed in the period d3 ′ (WJ5c).

  On the other hand, as shown in FIG. 20, when the first scan is detected in any of the periods d1, d2, and d3, the amplitudes of these Doppler signals are compared. When the Doppler signal in the period d1 is the largest, it is determined that the signal is detected in the period d1 (SJ7a). When the Doppler signal in the period d2 is the largest, it is determined that the signal is detected in the period d2 (SJ7b). When the Doppler signal in the period d3 is the largest, it is determined that the detection is performed in the period d3 (SJ7c).

  As described above, according to the present embodiment, when sequentially scanning a plurality of directions, depending on the result of detection in each direction, the result of the next scan is taken into account as necessary. It becomes possible to detect a detection object reliably. Furthermore, in the second scan, the direction of the detected object can be determined more quickly by skipping the direction in which the probability of the presence of the detected object is low.

Next, a case where scanning is performed in four directions in the high frequency sensor device of the present embodiment will be described.
FIG. 22 is a schematic plan view of an antenna 100 that can be used in the high-frequency sensor device of the present embodiment.
FIG. 23 is a schematic diagram showing that the direction of the radiation beam is changed by a switch operation in the antenna 100.

  The antenna 100 has a configuration in which parasitic elements 130, 132, 104, and 106 are arranged on the upper, lower, left, and right sides of the feeding element 102. These parasitic elements can be set to either a ground state or a floating state by switches SW1 to SW4 connected via control lines 110, 112, 134, and 136, respectively. By selectively bringing only one of the parasitic elements 104, 106, 130, 132 into a grounded state, the radiation direction of the main beam can be tilted up, down, left, and right. Further, since the parasitic elements 104, 106, 130, and 132 are excited by the feeding element 102 and excited in the same direction, either of the left and right parasitic elements 104, 106 and the upper and lower parasitic elements 130, 132 are not affected. By grounding one of them, the direction of the main beam can be inclined in a direction of about 45 degrees in plan view. By selecting the parasitic elements 104, 106, 130, and 132 that are grounded in this way, the direction of the main beam can be changed at intervals of 45 degrees.

Hereinafter, a case will be described in which scanning is repeatedly performed using such an antenna 100 in the four different directions as the period d1, the period d2, the period d3, and the period d4. Here, in the period d1, only SW2 of SW1 to SW4 is on and the others are off, and in the period d2, only SW4 is off and the others are on in SW1 to SW4, and the period d3 is only SW2 of SW1 to SW4. Is off and the others are on, and in the period d4, only SW4 of SW1 to SW4 is on and the others are off.
FIG. 24 is a table summarizing the cases in which the detection target can be identified by one scan in the present embodiment.
That is, when it is not detected in any of the periods d1 to d4, it is determined that it is not detected (SJ0). If the detection is performed only during the period d1, it is determined that the detection is performed during the period d1 (SJ1).
On the other hand, when the detection is performed only in the periods d1 and d2, it is determined whether the detection is performed in the periods d1 or d2 based on the magnitudes of these Doppler signals (SJ3a, SJ3b).

Similarly, when the detection is performed only during the periods d1 and d3, it is determined whether the detection is performed during the periods d1 or d2 based on the magnitudes of these Doppler signals (SJ5a, SJ5b).
In addition, when detection is performed in the periods d1, d2, and d3, it is determined whether the detection is performed in the periods d1, d2, and d3 based on the magnitudes of these Doppler signals (SJ7a, SJ7b, and SJ7c).
Further, when the detection is performed only during the periods d1 and d4, it is determined whether the detection is performed during the periods d1 or d4 based on the magnitudes of these Doppler signals (SJ9a, SJ9b).

When detection is made in each of the periods d1, d2, and d4, it is determined which of the periods d1, d2, and d4 is detected based on the magnitudes of these Doppler signals (SJBa, SJBb, and SJBc).
Similarly, when detection is made in each of the periods d1, d3, and d4, it is determined which of the periods d1, d3, and d4 is detected based on the magnitude of these Doppler signals (SJDa, SJDb, and SJDc).
When detection is performed in the periods d1, d2, d3, and d4, it is determined which of the periods d1, d2, d3, and d4 is detected based on the magnitude of these Doppler signals (SJFa, SJFb, SJFc, SJFd).

FIG. 25 to FIG. 36 are tables exemplifying the case where the result of the second scan is taken into consideration in the present embodiment.
For example, in the case of the specific example shown in FIG. 25, when the first scan is detected only in the period d2, it is possible to perform the scan while skipping the period d3 ′ and the period d4 ′ in the next scan. . This is because since the detection direction is not detected in the periods d3 and d4, the moving direction of the detected object is highly likely to be opposite to the scanning direction. Accordingly, in the second scan, it is possible to make a quick determination by scanning only in the period d1 ′ and the period d2 ′.

  Similarly, in the case of the specific example shown in FIG. 26, if the first scan is detected only in the period d3, the next scan can be skipped during the period d4 '. This is because, since the detection is not performed in the period d4 after the detection in the period d3, the moving direction of the detection target is highly likely to be opposite to the scanning direction. Accordingly, in the second scan, it is possible to make a quick determination by scanning only in the periods d1'd2 'and d3'.

  As shown in FIG. 27, when the first scan is detected only in the periods d2 and d3 and the Doppler signal in the period d2 is larger, the periods d3 ′ and d4 ′ are set in the next scan. You can skip and scan. This is because there is a high possibility that the detection in the period d3 is due to the side lobe, and since it is not detected in the period d4, the movement direction of the detected object is highly likely to be opposite to the scanning direction. It is. Therefore, in the second scan, it is possible to make a quick determination by scanning only in the period d1'd2 '.

  On the other hand, as shown in FIG. 28, when the first scan is detected only in the periods d2 and d3 and the Doppler signal in the period d3 is larger, the periods d2 ′ and d4 ′ are set in the next scan. You can skip and scan.

  In the first scan, the Doppler signal is larger in the period d3 than in the period d2, which means that there is a person where the radio wave emission range in the period d2 and the radio wave emission range in the period d3 overlap. In other words, it means that there is a high possibility that a person exists on the side of the radiation range of the radio wave in the period d3. For example, if the radio wave emission range is 40 ° to 140 ° in the period d2 (based on the 3 dB down beam width) and the radio wave emission range is 120 to 240 ° in the period d3, there is a person in a direction around 130 °. The possibility is high. Accordingly, if the period d2 ′ is skipped in the second scan and the periods d1 ′ and d3 ′ are scanned, the influence of the radio wave scanning order and side lobes can be eliminated, and the position of the detected object can be accurately identified, and the response Detection with excellent properties becomes possible.

  In addition, as shown in FIG. 29, when the first scan is detected only in the period d4, in the next scan, the periods d1, d2, d3, d4 are sequentially scanned, and the result is obtained. Judgment can be made in consideration of the magnitude of the Doppler signal.

  On the other hand, as shown in FIG. 30, when the first scan is detected only in the periods d2 and d4 and the Doppler signal in the period d2 is larger, the periods d3 ′ and d4 ′ are set in the next scan. You can skip and scan.

  The radio wave emission range in the period d2 and the radio wave emission range in the period d4 are in opposite directions, and the Doppler signal is larger in the period d2 than in the period d4 in the first scan. As a result of removing the influence of the side lobe in FIG. 2, there is a high possibility that a person exists on the side of the radio wave emission range in the period d2. Therefore, if the period d3 ′ and d4 ′ are skipped in the second scan and the period d1 ′ and period d2 ′ are scanned, the influence of the radio wave scan order and side lobe is removed, and the position of the detected object is accurately identified. Detection with excellent responsiveness.

  Then, the determination can be made based on the magnitude of the obtained Doppler signal.

  Further, as shown in FIG. 31, when the first scan is detected only in the periods d2 and d4 and the Doppler signal in the period d4 is larger, the periods d2 ′ and d3 ′ are set in the next scan. You can skip and scan.

  Then, the determination can be made based on the magnitude of the obtained Doppler signal.

  As described above, according to the present embodiment, in the high-frequency sensor device that detects a detection target by sequentially scanning a plurality of directions, it is possible to perform detection more reliably and quickly by removing the influence of side lobes. Detection is possible. In addition, by taking into account the influence of side lobes and the direction of movement of the detected object, it is possible to skip detection in a predetermined direction during the second scan, and detect the detected object more quickly and reliably. can do.

  By the way, in the control judgment circuit 26 (see FIG. 1) of the high frequency sensor device according to the present embodiment, the voltage value (V0) of the Doppler signal when no person is present in the radio wave radiation direction depends on the detection range. If the threshold value (V0 ± α: α> 0) is set, the radio wave radiation direction is switched, and the voltage value of the Doppler signal exceeds the threshold value in either direction (for example, on the plus α side or minus) When the threshold value is exceeded on either side of α), it recognizes that a person is present (determines that a human body has been detected), and that is the first radio wave emitted in one scan. If the direction is a direction, the direction in which the human body is detected is determined based on the first scan data, and if the direction is the second or later direction in which radio waves are radiated, based on the previous scan data and the next scan data. (For example, two directions (Refer to FIG. 5 to FIG. 11 for the case where the scanning is sequentially performed separately).

  Here, as shown in FIG. 37, a second threshold value V0 ± β (α> β> 0) having a width narrower than the first threshold value V0 ± α is set. When the voltage value VP or VB of the Doppler signal in the radiated direction (period d1) is (V0 + α) ≧ VP> (V0 + β) or (V0−α) ≦ VB <(V0−β) ) And the next scan data may be used to determine the presence or absence of human body detection. Thereby, responsiveness and detection accuracy can be further improved. Note that the determination by providing the second threshold in this way is also applicable to the above-described three-direction scan and four-direction scan.

  In the example shown in FIG. 37, (V0 + α) ≧ VP> (V0 + β), (V0−α) ≦ VB <(V0−β) in the period d1, and d2 = 0, so that the next scan is performed. judge. Since d1 ′ = 1 and d2 ′ = 0 in the next scan, it is determined that the main beam 206 (see FIG. 5B) has detected when SW1 is ON, and the control determination circuit 26 outputs a determination signal 1 . In the next scan, if d1 ′ = 0 and d2 ′ = 0, it is determined that no detection is performed. If d1 ′ = 0 and d2 ′ = 1, the main beam 202 (see FIG. 5A) is displayed when SW2 is ON. ). Further, in the next scan, if d1 ′ = 1 and d2 ′ = 1 and d1 ′> d2 ′, it is determined that the detection is performed when SW1 is ON, and if d1 ′ <d2 ′, SW2 is ON. It is determined that it was detected at the time.

  The voltage level of the Doppler signal does not always fluctuate equally between the + direction side and the − direction side with respect to the voltage value V 0 when no person is present in the radio wave radiation direction. In addition, if the voltage value V0 fluctuates due to manufacturing variations and usage environments, the detection accuracy may decrease.

  Therefore, as threshold determination, a voltage amplitude value (PB0) set in advance according to the detection range is used as a threshold, and the radiation direction of radio waves is switched, and radio waves are radiated in the same direction as shown in FIG. The maximum voltage amplitude value PBMAX is calculated from the maximum voltage value VP and the minimum voltage value VB of the Doppler signal during the period. If PBMAX> PB0, the Doppler signal is detected. In this way, even if the voltage value V0 fluctuates, the detection accuracy is not affected. Such threshold determination can also be applied to the above-described three-directional scan and four-directional scan.

  In the example of FIG. 38, when d2 = 0 and d2 ′ = 0, if PBMAX> PB0 in the direction in which radio waves are first emitted (period d1), it is assumed that a Doppler signal has been detected, and SW1 is turned on. It is determined that a human body has been detected at the time. If PBMAX ≦ PB0 in the period d1, it is determined that the human body is detected when SW1 is ON in the case of PBMAX> PB0 in the next scanning period d1 ′.

  In the high-frequency sensor device according to the present embodiment (see FIG. 1), the control determination circuit 26 indicates whether or not the detection target is detected to the load control circuit 30 or to the outside of the device via the load control circuit 30. A determination signal and a monitor signal indicating in which direction the electron beam is emitted are output.

  FIGS. 39 to 42 are diagrams showing what determination signals and monitor signals are output when the human body detection is confirmed by sequentially switching the electron beam in two directions.

  The ratio of the time during which the electron beam is radiated to one side and the time from which the electron beam is radiated to the other is the same, but the monitor signal output to the outside in which direction the radio beam is radiated is shown in FIGS. As shown in Fig. 3, when the radiation direction of the radio wave beam is switched, a pulse signal whose time is shorter than the switching speed is used, a pulse signal corresponding to each radiation direction is used, and the duty of the pulse signal corresponding to each radiation direction is used. (Duty) is changed at a preset rate.

  On the other hand, when a radio wave beam is scanned in a plurality of directions and human body detection is confirmed in any direction, a determination signal is output in a predetermined manner. For example, in the case of sensing by constantly scanning an electron beam, if human body detection is confirmed in a certain direction, a determination signal may be output during the next one scan, or a preset time (for example, from 1 millisecond to The determination signal may be output only for 1 second.

  In addition, when the human body detection is confirmed by scanning the electron beam, the radiation direction of the radio wave beam is fixed to the direction detected by the human body, and when further sensing is performed by narrowing the detection range, the Doppler signal in the direction where the human body detection is confirmed A determination signal can also be output according to the frequency and voltage value. However, in the control determination circuit 26 of the present embodiment, the timing at which the determination signal is output differs between when the human body detection is confirmed at step 1 and when the human body detection is confirmed at step 2.

  Even if the operation of approaching the hand to the high-frequency sensor device is the same, depending on the timing of approaching the hand and the timing of scanning the radio wave beam, as shown in FIG. As shown in FIG. 2, there are cases where the approach of the hand is determined by two scans. As is apparent from the determination signals in FIGS. 39 and 40, the step 1 determination signal (in FIG. 6), which is an output signal from the control determination circuit 26, is determined when the determination is performed once and when the determination is performed twice. The number of times and the output timing of the pulse of the signal corresponding to the determination signal 1 are different.

  For example, when scanning an electron beam in two directions at a switching speed of 10 milliseconds, human body detection is first confirmed in the direction (step 1) in which radio waves are emitted as shown in FIG. The timing at which the determination signal is output differs from that when human body detection is confirmed in the direction in which the radio wave is emitted (step 2) by 20 milliseconds.

  In this case, for example, when the electron beam is scanned in the left and right directions and the approach of the hand is determined in the right direction (step 1), the volume is increased by a fixed amount, and the approach of the hand is determined in the left direction (step 2). In the case of a switch that reduces the volume by a certain amount when it is done, there is no problem.

  However, if you try to control the volume in analog using the frequency or voltage value of the Doppler signal after confirming the approach direction of the hand (after confirming the radio wave direction), the hand approaches at the same speed and time. In this case, when the approach of the hand is determined in the right direction (step 1), the sound volume changes greatly dynamically, but when the approach of the hand is determined in the left direction (step 2), the volume changes small. The rate of change with respect to the approaching action of the hand varies depending on the detection confirmation direction.

  As described above, the switch for changing the high-frequency sensor device of this embodiment into a physical quantity in an analog manner (for example, detecting the direction in which the hand approaches and the amount of water discharged from the faucet device according to the approach speed (frequency) of the hand, illumination In the case of using as a light amount of equipment, heat quantity of heating equipment, and air quantity of blower equipment), the output timing of the judgment signal is different, and it may not be possible to obtain an even operational feeling.

  Therefore, when radiating a radio wave beam in a plurality of directions, as shown in FIG. 41, when human body detection is first determined in a direction in which radio waves are radiated in one scan, a determination signal is output. In addition, a waiting time for one scan (determination signal output waiting time) is set. That is, even when the determination is confirmed by one scan, the step 1 determination signal is not output during the determination period by the second scan (the second scan is performed after the determination signal output waiting period elapses). The step 1 determination signal is output at the same timing as the above case.

  In this way, it is possible to suppress the output timing of the determination signal from being different from when human body detection is confirmed in another direction, so that the above-described problems can be solved and an equivalent operational feeling can be obtained. It should be noted that providing the determination signal output standby time in this way is also applicable to the above-described three-way scan and four-way scan.

  Further, the high-frequency sensor device according to the present embodiment (see FIG. 1) includes both means for outputting a monitor signal and means for outputting a determination signal, but in which direction when scanning an electron beam. As a monitor signal output means for confirming whether an electron beam is radiated, one output is used as a determination signal output means when human body detection is confirmed in any direction and the radiation direction of the radio wave is fixed It can also be used as a means. Further, the ratio of the time during which the electron beam is emitted to one side and the time during which the electron beam is emitted to the other is the same, but the ratio may be changed according to the application and the use environment.

  The above-described high-frequency sensor device is provided with a load control circuit. However, when the load control circuit is built in an externally connected device, the voltage level of the monitor signal output from the control determination circuit The presence or absence of human body detection can be easily achieved by checking human body detection in either direction when the electron beam is simply scanned, and changing to low level when the radiation direction of radio waves is fixed. Can be recognized, and the controllability of the load is improved. In addition, as a form in which the determination signal is output to the outside without going through the load control circuit, the load can be directly driven by providing a plurality of output terminals for outputting the determination signals in the number of scan directions. In addition, when the determination information obtained by the high-frequency sensor device of the present embodiment is separately transmitted to a device installed in another place, a determination signal is output at a predetermined timing from one output terminal. You can do it.

  In the example in which the electron beam shown in FIG. 42 is scanned in two directions, a determination signal is output from one output terminal. In the determination signal shown in FIG. 42, a pulse signal P1 for informing that a human body has been detected, a pulse signal P2 for informing which direction is detected, and pulse signals P3 and P4 for informing how fast the vehicle is moving. Output in order. The time for which this determination signal is output is shorter than the time required for one scan (step 1 time + step 2 time).

  By changing the time from when the pulse signal P1 is output to when the pulse signal P2 is output, it is possible to easily notify which direction the detection is made. In the example of FIG. 42, since the human body is detected when the radiation direction is step 1, the pulse signal P2 is output at the timing indicated by the solid line in the determination signal, but the human body is detected when the radiation direction is step 2. Then, the pulse signal P2 is output at the timing indicated by the broken line in the determination signal. Further, although the initial speed information is output from the rise of the pulse signal P3 to the rise of the pulse signal P4, the speed information may be continuously output.

  In the example of FIG. 42, the determination information (determination signal) is changed to the outside by changing the timing of outputting the pulse signal as means for notifying in which direction the human body is detected and at what speed. Although it is output, it is also possible to notify by changing the number of pulse signals output within a predetermined time and the width of the pulse signal (for example, the time when it is at the H level). In addition, outputting the determination information by changing the timing of outputting the pulse signal, the number of pulse signals, and the width of the pulse signal as described above is also applicable to the above-described three-direction scan and four-direction scan.

The embodiments of the present invention have been described above with reference to the drawings.
However, the present invention is not limited to these embodiments. Even if a person skilled in the art changes the design regarding the shape, size, arrangement, etc. of the antenna, high frequency switch, oscillation circuit, detection circuit, control unit, etc. constituting the high frequency sensor device, the present invention is not required. It is included in the scope of the invention.

It is a block diagram of the high frequency sensor apparatus concerning an embodiment of the invention. It is a top view showing an example of the microstrip antenna provided in the high frequency sensor apparatus of this embodiment. It is AA sectional drawing of FIG. It is a schematic diagram showing the change of the radiation direction of a radio wave beam by operation of switch 120,124. It is a schematic diagram for demonstrating generation | occurrence | production of a side lobe. It is a graph for demonstrating the detection method performed in the high frequency sensor apparatus of this embodiment. FIG. 5 is a graph showing that a predetermined threshold is set, and that “not detected” is determined when the Doppler signal does not exceed these thresholds, and “detected” is determined when the threshold is exceeded. It is the table | surface showing the method of specifying a to-be-detected body based on a criterion. It is the table | surface showing the method of specifying a to-be-detected body based on a criterion. It is a graph which illustrates the waveform of a Doppler signal. It is a graph which illustrates the waveform of a Doppler signal. It is a schematic diagram which illustrates the radiation | emission direction of a main beam. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a table | surface showing the method of determination in the case of scanning sequentially in 3 directions. It is a schematic diagram showing that the detection object 900 is moving in the direction opposite to the scanning direction, that is, the direction from d2 to d1. 1 is a schematic plan view of an antenna 100 that can be used in the high-frequency sensor device of the present embodiment. FIG. 5 is a schematic diagram showing that the direction of a radiation beam is changed by a switch operation in antenna 100. In this example, it is a table that summarizes the cases where the object to be detected can be specified by a single scan. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. 6 is a table illustrating a case where a result of a second scan is taken into consideration in the present embodiment. In the high frequency sensor apparatus of this embodiment, it is a graph for demonstrating the method of switching an electron beam to 2 directions sequentially and detecting a to-be-detected body. In the high frequency sensor apparatus of this embodiment, it is a graph for demonstrating the method of switching an electron beam to 2 directions sequentially and detecting a to-be-detected body. In the high-frequency sensor device of this embodiment, it is a graph showing what kind of determination signal is output when the electron beam is sequentially switched in two directions and human body detection is confirmed. In the high-frequency sensor device of this embodiment, it is a graph showing what kind of determination signal is output when the electron beam is sequentially switched in two directions and human body detection is confirmed. In the high-frequency sensor device of this embodiment, it is a graph showing what kind of determination signal is output when the electron beam is sequentially switched in two directions and human body detection is confirmed. In the high-frequency sensor device of this embodiment, it is a graph showing what kind of determination signal is output when the electron beam is sequentially switched in two directions and human body detection is confirmed.

Explanation of symbols

 DESCRIPTION OF SYMBOLS 10 High frequency part, 12 High frequency circuit, 14 Oscillation circuit, 16 Detection circuit, 20 Control part, 22 Amplifier, 24 Comparator, 26 Control judgment circuit, 30 Load control circuit, 32 Radio wave scanning control circuit, 100 Antenna, 101 Substrate, 102 Antenna element (feed element), 104, 106 Antenna element (parasitic element), 108 Feed line, 110 Control line, 115 Ground line, 116 Ground electrode, 118 Ground line, 120, 124 Switch, 130, 132 Parasitic element, 202 Main beam, 204 Side lobe, 206 Main beam, 208 Side lobe, 900 Object to be detected, SW1 to SW4 switch

Claims (6)

An oscillation circuit for generating a transmission wave;
An antenna that radiates the transmitted wave and receives a reflected wave from the object of the transmitted wave as a received wave;
A detection circuit for detecting the received wave;
A control determination circuit for determining the presence or absence of detection of the detection object based on the Doppler signal included in the detection circuit;
A radio wave scanning control circuit that outputs to the antenna a control signal for changing the direction of radio waves radiated from the antenna;
With
The control determination circuit sequentially scans a main beam output from the antenna in a plurality of different directions according to a control signal from the radio wave scanning control circuit to check a Doppler signal included in the received wave, and When the Doppler signal from the direction in which radio waves are emitted for the first time in a single scan exceeds a preset threshold value, the presence or absence of the detected object is determined based on the Doppler signal. The Doppler signal from the direction in which radio waves are radiated for the first time in the scan does not exceed a preset threshold, and the Doppler signal from the direction in which radio waves are radiated after the second exceeds a preset threshold. In this case, the high-frequency sensor device is characterized by determining the presence or absence of a detection object based on the Doppler signal obtained in the scan and the next scan.   As a result of examining the Doppler signal obtained in the next scan, if the Doppler signal does not exceed the threshold value in any of the plurality of directions, the control determination circuit performs the Doppler signal in the one scan. The high-frequency sensor device according to claim 1, wherein it is determined that the detected object is detected in the direction in which the signal exceeds the threshold.   The control determination circuit examines the Doppler signal obtained in the next scan, and as a result, when the Doppler signal exceeds a predetermined threshold in at least one of the plurality of directions, the control determination circuit performs the one scan. The Doppler signal exceeding the threshold is compared with the Doppler signal exceeding the threshold in the next scan, and it is determined that the detected object is detected in the direction in which the Doppler signal having the largest amplitude is detected. The high-frequency sensor device according to claim 1.   As a result of examining the Doppler signal obtained in the next scan, the control determination circuit does not exceed the threshold value, and the Doppler signal from the direction in which the first radio wave is radiated does not exceed the threshold value. 2. When the Doppler signal from the direction in which the signal is emitted exceeds the threshold, it is determined that the detected object is detected in the direction in which the second and subsequent radio waves are emitted. High frequency sensor device.   5. The high-frequency signal according to claim 1, wherein the control determination circuit skips at least one of the plurality of directions when examining the Doppler signal obtained in the next scan. 6. Sensor device.   The high-frequency sensor device according to claim 1, wherein the control determination circuit outputs a determination signal indicating the presence or absence of the object to be detected after the next scan is completed.

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