JP2004317143A - Object state determining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately determine the state of an object by accurately detecting whether the object is relative moving close or away from a prescribed position through the use of a Doppler sensor. <P>SOLUTION: This object state determining apparatus is provided with the Doppler sensor 11 having a plurality of mixers M1 and M2; a movement analyzing part 12 for analyzing whether the object is moving close or away on the basis of output of the plurality of mixers; a Doppler wave cycle detecting part 13 for detecting the occurrence of Doppler waves on the basis of output of the second mixer M2; a Doppler wave cycle counting part 14 for counting the occurrence cycles of the Doppler waves from output of the Doppler wave cycle detecting means and output of the movement analyzing part; and a state determining/controlling part 15 for determining the state (presence, separation, etc.) of the object on the basis of the changing state of count values of the Doppler wave cycle counting part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an object state determination device that can accurately detect relative approach / separation from a predetermined position to an object using a Doppler sensor.
[0002]
[Prior art]
2. Description of the Related Art An automatic flushing device for a toilet, an automatic toilet seat device, and a security system for a vehicle are equipped with a sensor system that detects a state of movement of an object such as a person by a sensor and performs a predetermined operation. In this type of sensor system, a microwave sensor or an infrared sensor is generally used for detecting approach, separation, stop, absence, etc. of a person.
[0003]
For example, in the sensor system (detection device) of Patent Document 1, a microwave is emitted from the urinal front side, a microwave reflected from a person is received, and a power spectrum of a Doppler frequency signal is obtained, and a human urinal is obtained. It can detect approaching or leaving the urinal.
[0004]
[Patent Document 1]
JP-A-09-080150
[0005]
[Problems to be solved by the invention]
However, this type of sensor system is likely to be affected by surrounding conditions, such as detecting the movement of a person other than a small user, and it may be difficult to perform an accurate operation. In order to reliably determine the state of movement of a person, it is necessary to accurately determine the approach and separation of the person to and from the detection device.
[0006]
In addition, a two-frequency Doppler sensor may be used to determine the distance between the object and the sensor. The two-frequency Doppler sensor uses a mixer operating at two different frequencies, and the distance to the target can be specifically expressed by the following equation.
R0 = c · ΔΦ / 4π · (f2-f1) (1)
R0: distance between sensor and target
f1: first frequency
f2: second frequency
ΔΦ: phase difference between two Doppler waves
c: speed of light
[0007]
For example, if f1 = 24.14 GHz and f2 = 24.15 GHz, the difference between the two frequencies is 10 MHz. Since the frequency difference is very small compared to the two frequencies, the frequency of the Doppler signal (Doppler frequency) based on the local oscillation frequency of each frequency can be regarded as substantially equal.
[0008]
Specifically, when the relationship between the distance and the phase difference is calculated using Expression (1), the distance is about 4 cm per degree of the phase difference. One cycle of the Doppler wave occurs when the Doppler wave moves a half distance of the wavelength λ. In the above example, the wavelength λ is approximately 1.24 cm, and a Doppler wave does not occur unless it moves by 0.62 cm.
[0009]
Therefore, the effective phase difference becomes about 0.15 degrees to 180 degrees, and when converted into a distance, a distance from 0.62 cm to 7.5 m can be calculated with a resolution of 0.62 cm.
[0010]
In the two-frequency Doppler sensor, the approach or separation of a person can be identified based on the signal strength of the Doppler signal. , The signal strength may be different. Further, the emission of the Doppler wave from the antenna spreads as the distance increases, but a farther object is detected in a wider range. Therefore, even for a Doppler signal having a signal strength equal to or higher than a predetermined level, a farther motion than a near motion is detected in a wider range, which causes a malfunction.
[0011]
In principle, a two-frequency Doppler sensor can measure a distance to an object with high accuracy. However, in practice, there is a problem in processing when detecting a deviation between the two frequencies and a phase difference, and it is impossible to calculate the distance with the resolution as calculated. Generally, the resolution is about 2 degrees of phase difference (about 8 cm in distance). Further, a circuit for detecting with high accuracy becomes complicated and cannot be inexpensive.
[0012]
Also, a pulse radar based on the reflection time of light or millimeter-wave pulses may be used for distance measurement. Since this pulse radar measures the response time of a pulse reflected from an object, it is not suitable for measurement of an object at a short distance.
[0013]
The present invention has been made in view of the above-described background, and an object of the present invention is to accurately detect a state of an object, such as presence, passage, and movement from a predetermined position, using a Doppler sensor. It is an object of the present invention to provide a device for determining an object state.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the object state determination device of the present invention includes a Doppler sensor having a plurality of mixers, an operation analysis unit that analyzes a movement of a target object from outputs of the plurality of mixers, Doppler wave cycle detecting means for detecting generation of a Doppler wave based on an output of any of the mixers, an output of the Doppler wave cycle detecting means, and a Doppler wave for counting a generation cycle of the Doppler wave from an output of the operation analyzing means. A cycle counting means and a state determination means for determining a state of the object based on at least an output from the Doppler wave cycle counting means are provided. In this specification, it goes without saying that the object state determination device can determine not only a “object” but also a “person”.
[0015]
Further, in the present invention, the motion analysis means can be configured to determine approach or separation based on outputs from at least two of the plurality of mixers. Further, the Doppler sensor can be a two-output Doppler sensor. As an example, the Doppler sensor may be composed of a local oscillator, an antenna provided at an end of an output line of the local oscillator, and two mixers separated by λ / 8 on the output line. it can.
[0016]
There are various types of operation states determined by the state determination unit. For example, the operation state that detects the presence of the target object from a change (frequency, etc.) of the count value stored in the Doppler wave cycle counting unit is detected. Alternatively, the passage of the object can be detected from a change (frequency or the like) in the count value stored in the Doppler wave cycle counting means. Furthermore, in addition to detecting movement to a predetermined position, various states can be detected.
[0017]
From the outputs of the plurality of mixers of the Doppler sensor, the moving direction (approach, separation, etc.) of the object can be determined. Further, the generation cycle of the Doppler wave can be detected from the output of the at least one mixer, and the moving distance of the object required for one cycle of the Doppler wave to be determined from the frequency of the Doppler wave. Can be. Accordingly, if the object is moving in the same direction, the count value stored in the Doppler wave cycle counting means is incremented or decremented each time the Doppler wave cycle detecting means detects one cycle, so that the count value is calculated. The moving distance of the object can be obtained from the change amount. When the object does not move, the count value does not change. When the moving speed of the object is slow, the change in the count value is slow. Further, when the movement direction is reversed, the increase / decrease of the count value is also reversed, so that the state of approach / stop / separation of the object can be determined by monitoring the change in the count value. Then, if the stop of the movement can be detected, it can be known that the target object remains at that position, and the presence can be detected. Further, by detecting approach and separation, it can be determined that the target has passed in front of the Doppler sensor 11.
[0018]
Further, a signal strength determining means for determining a signal strength of the Doppler signal based on an output from at least one of the mixers is provided. It can be done with consideration. In the embodiment, the signal strength judging means is realized by a signal strength measuring section and a functional portion for determining a weight according to the signal strength in the operation analyzing means. By adopting such a configuration, the influence of the movement of the target object close to the object state determination device (Doppler sensor) increases, so that a malfunction due to the movement of the surrounding objects can be suppressed.
[0019]
On the other hand, on the premise of the invention described above, the apparatus further comprises a reference point detecting means for detecting that the object has reached a predetermined reference point, and wherein the state determining means is configured to count the Doppler wave cycle counting means from the reference point. It is preferable to determine the state of the object from the amount of change in the numerical value. As described above, since the moving distance of the object can be obtained from the change amount of the count value, by detecting the reference point, the object moves away / approaches the desired position based on the moving distance from the reference point. You can know the state that you have done.
[0020]
As a configuration for detecting the reference point, various types can be used, and as a configuration using the output of the Doppler sensor, for example, a frequency measurement unit that determines a generation frequency of a Doppler signal is provided, The reference point detection means may be configured to determine that the target is present at the reference point when the output of the frequency measurement means has a predetermined frequency change within a predetermined time. Further, as another method, a signal strength detecting means for detecting a signal strength of the Doppler signal is provided, and the reference point detecting means is configured to detect a signal strength of the Doppler signal based on an output of the signal strength detecting means. Can be determined to be present at the reference point when is continued for a predetermined time. The signal strength detecting means corresponds to a signal strength measuring unit in the embodiment. The signal strength detecting means may be shared with a part of the signal strength determining means for weighting the count of the Doppler wave cycle counting means, or may be configured as a separate member.
[0021]
Further, the reference point detecting means may determine that the target object is present at the reference point when the target object is reversed from the approaching state to the separated state, or every predetermined time in the Doppler wave cycle counting means. When the change in the count value is equal to or less than a predetermined value, it may be determined that the object is present at the reference point, or when the change in the count value for each predetermined time in the Doppler wave cycle counting means is equal to or less than the predetermined value. It can be realized by various judgment algorithms, such as judging that an object is present at the reference point when the value exceeds a predetermined value from a certain state. The specific detection algorithm of the above-described reference point detection means may be used alone, or may be implemented in combination with an appropriate one. Of course, the present invention is not limited to the above-listed examples.
[0022]
Further, when the motion analysis unit detects the approach of the target object after the reference point detection unit determines that the target object is present at the reference point, the Doppler signal serving as the detection source is a malfunction signal. And controlling the Doppler wave cycle counting means. Still further, after the reference point detection means determines that the target object is present at the reference point, the motion analysis means detects that the target object has been continuously approached and then separated. In that case, the Doppler wave cycle counting means may be controlled by determining the Doppler signal that is the source of the detection as a malfunction signal. Here, controlling the Doppler wave cycle counting means may mean, for example, that “counting processing is not performed” even when a Doppler wave cycle is detected.
[0023]
The object state determination device of the present invention can further include control means for controlling predetermined devices such as a solenoid valve, a lamp, and an alarm. With this control means, the start and stop of the electromagnetic valve, the lamp, the alarm, and the like can be performed according to the movement of the object.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a preferred embodiment of the present invention. As shown in FIG. 1A, the object state determination device 10 of the present embodiment includes a Doppler sensor 11, an operation analysis unit 12, a Doppler wave cycle detection unit 13, a Doppler wave cycle counting unit 14, a state A determination / control unit 15;
[0025]
The Doppler sensor 11 includes a horn antenna (also serving as a transmitting antenna and a receiving antenna) HA, two mixers M1 and M2, and a local oscillator L. O. And the local oscillator L. O. Emits the generated microwave from the horn antenna HA, and receives the reflected microwave by the horn antenna HA.
[0026]
The local oscillator L. O. The first and second mixers M1 and M2 are provided between the horn antenna HA and the horn antenna HA. The first and second mixers M1 and M2 are arranged such that the outputs have a phase difference of 90 degrees from each other. I have. Specifically, the other end of the waveguide formed integrally with the horn antenna HA is closed, and a local oscillator is provided at the other end. The horn antenna HA, the first mixer M1, the second mixer M2, and the local oscillator L. O. And the adjacent first and second mixers M1 and M2 are separated by λ / 8.
[0027]
In FIG. 1A, the horn antenna HA, the first mixer M1, the second mixer M2, the local oscillator L. O. Are connected by a line, which is described for convenience in order to show a signal transmission path and the like. The horn antenna and the waveguide following the horn antenna are three-dimensional circuits and the inside is a space. Signals are transmitted and injected by installing components at appropriate positions in the space. Of course, although not shown, the local oscillator L. O. Is output to each mixer.
[0028]
Further, as shown in FIG. 1B, it can also be constituted by a planar circuit using a microstrip line. That is, the patch antenna PA, the first mixer M1, the second mixer M2, and the local oscillator L. are arranged at predetermined intervals from the end with respect to the linear microstrip line SL. O. Connect. Then, the distance between the first and second mixers M1 and M2 is set to be λ / 8. Of course, the specific circuit configuration is not limited to the illustrated one. In the following description, an example in which a horn antenna HA is used as an antenna constituting the Doppler sensor 11 will be described. However, the same applies to a planar circuit using a patch antenna PA as shown in FIG.
[0029]
In each of the above-described configurations, for example, based on the first mixer M1, the reflected wave from the horn antenna HA or the like is input to the second mixer M2 with a delay of λ / 8, while the local oscillator L. O. Is input to the second mixer M2 λ / 8 earlier. Therefore, the phase difference between the outputs of the first mixer M1 and the second mixer M2 is λ / 4 (90 degrees).
[0030]
The motion analysis unit 12 receives the reflected waves from the object received by the horn antenna HA via the first and second mixers M1 and M2, and determines the motion of the object. In the present embodiment, approach and separation are determined from changes in the phases received by the first and second mixers M1 and M2. Further, depending on the state of the object to be determined, the motion analysis unit 12 has a function of specifying that the target object has reached the reference point. Of course, it goes without saying that the reference point detecting function for detecting that the reference point has been reached may be provided independently of the motion analysis unit 12.
[0031]
FIG. 2 is a conceptual explanatory diagram regarding the phases of the outputs of the mixer M1 and the mixer M2 when approaching / separating. When the Doppler signal is generated, a 90 degree phase difference occurs between the output of the mixer M1 and the output of the mixer M2. Considering a signal at the time of approach from the viewpoint of a change in phase, the signal changes from point P1 to point P2, whereas a signal at the time of separation changes from point P2 to point P1.
[0032]
That is, at the time of approach and at the time of departure, the phase from the other mixer is inverted on the basis of the signal from one mixer. Using this phase difference, the signal output from the mixer is binarized, and the two signals can be compared to determine whether approaching or moving away.
[0033]
One cycle of the Doppler wave occurs when the Doppler wave travels a distance of １ ／ of the wavelength (for example, a distance equivalent to 0.62 cm when the transmission frequency f is 24.2 GHz). Therefore, with respect to approach / separation, if there is a movement of λ / 2 (change in phase for one cycle), it is possible to determine approach / separation.
[0034]
In the object state determination device 10 of the present embodiment, one local oscillator L. O. Is used to supply the local oscillation signal to the two mixers M1 and M2. Therefore, it is not necessary to consider the frequency stability. It is only necessary to determine whether or not they have separated. No other complicated circuits are required.
[0035]
The Doppler wave cycle detector 13 detects the occurrence of a Doppler wave from the output of the second mixer M2. The Doppler wave cycle counting unit 14 that has received the output of the Doppler wave cycle detection unit 13 counts Doppler wave generation cycles.
[0036]
That is, as described above, from each of the mixers M1 and M2 of the Doppler sensor 11, one cycle of the Doppler signal is generated when the object moves a distance of λ / 2. When the Doppler wave is considered by a change in phase, the distance from the Doppler sensor 11 to the object changes by one wavelength λ (actually, it changes by half a wavelength λ / 2 to detect a reciprocating signal). This means that the phase changes 360 degrees continuously.
[0037]
On the other hand, when the Doppler sensor 11 mixes the transmitted wave and the reflected wave reflected from the object by the mixers M1 and M2, the phase difference between the transmitted wave and the reflected wave appears in its output (Doppler signal). Is changed by 360 degrees, the phase of the Doppler signal also changes by 360 degrees. That is, when the distance from the Doppler sensor 11 to the object moves by a half wavelength λ / 2, a Doppler signal for one cycle (a signal whose phase has changed by 360 degrees) is output.
[0038]
Therefore, the output of one of the mixers (the second mixer M2 in the present embodiment) is provided to the Doppler wave cycle detector 13, and the Doppler wave cycle detector 13 detects a Doppler signal for one cycle. Then, one pulse is output. From this, the moving distance can be calculated by counting the number of pulses output according to the number of cycles in which Doppler waves are continuously generated by the Doppler wave cycle counting unit 14.
[0039]
However, the Doppler signal for one cycle is output when the object moves by λ / 2, and the moving direction does not matter. That is, one pulse is output from the Doppler wave cycle detector 13 even when the object approaches λ / 2, and one pulse is output from the Doppler wave cycle detector 13 even when the object separates λ / 2.
[0040]
Therefore, if a one-cycle Doppler signal is generated as described above, the motion analyzer 12 can determine whether the one-cycle Doppler signal is approaching or moving away. Is given to the Doppler wave cycle counting unit 14, and if the generated one cycle is a departure, the number of cycles is set as a positive count, and if the approach is close, a negative count is set as a negative count, so that the movement amount of the object can be accurately measured. Become. In other words, when moving in the opposite direction for one cycle, the count is set to +1. When approaching for one cycle, the count is set to -1. The relative distance from the measurement start point (reference point) is calculated from the count and the distance for one cycle. Can be.
[0041]
Specifically, the Doppler wave cycle counting unit 14 executes the flowchart shown in FIG. First, it waits for detection of the occurrence of one cycle of Doppler signal (ST11). Specifically, it is determined whether or not a pulse has been output from the Doppler wave cycle detector 13. If a one-cycle Doppler signal is detected, it is determined whether the signal is based on approach or separation (ST12). Specifically, the determination is made based on the determination result signal from the operation analysis unit 12. If one generated cycle is separated, the number of cycles is set to a positive count (ST13), and if approaching, a negative count is made (ST14). Then, by repeatedly executing the above-described processing, the Doppler wave cycle counting unit 14 stores a cumulative value (count value) associated with the moving distance in consideration of the moving direction.
[0042]
This makes it possible to quantitatively measure the movement of the object. That is, every time a Doppler wave is detected for one cycle, the accumulated value of the Doppler wave cycle detector 13 is set to “+1” when moving in the separating direction and “−1” when moving in the approaching direction. From the difference between the accumulated values stored in the Doppler wave cycle counting unit 14 at two different times and the travel distance for one cycle, it is possible to calculate the distance between the points that existed at the two times. it can. Further, assuming that one of the two times is a time when the object is present at a certain reference position (reference point), the relative distance from the reference point can be calculated.
[0043]
Note that the Doppler wave cycle counting unit 14 does not operate by software processing as described above, and may be configured by hardware using an up-down counter or the like, for example.
[0044]
The state determination / control unit 15 determines the state of the object based on at least the output of the Doppler wave cycle counting unit 14. Further, depending on the type of state to be determined, the determination result signal from the operation analysis unit 12 is also used as information for determination. The types of states to be specifically determined and the determination algorithm are as follows. Of course, all or a plurality of functions may be incorporated, and an arbitrary function may be realized by a changeover switch or other means, or only one predetermined function may be incorporated. Further, the state determination / control unit 15 can perform control of a solenoid valve, control of a motor, control of a warning, and the like for a control target device (not shown) according to the state of the determined object. .
[0045]
Here, the presence detection function, which is one of the state determination functions in the state determination / control unit 15, determines a state in which a target (for example, a person) has approached and has stopped. That is, when the object approaches and stops in front of the Doppler sensor 11, it means that a person is present at that location until a new separation signal is generated. According to this determination method, it is possible to determine a state in which a person approaches and stops, so that it can be widely used as an automatic door, a seating sensor of a chair or a toilet, a sensor used for the presence or absence of a vehicle in a parking lot, and the like.
[0046]
Actually, in consideration of the resolution of the Doppler sensor 11, when the object is a human, it is difficult to completely stop including the entire posture, and even if both feet stop at the same position, Is slightly moved, and accordingly, an approach / separation signal is also generated.
[0047]
On the other hand, the Doppler sensor 11 outputs a Doppler signal for one cycle when the object moves by a predetermined distance (λ / 2). Therefore, the operation speed of the target object can be detected based on the frequency at which the Doppler signal is generated. That is, it can be said that when the frequency of the Doppler signal is low, the operation of the object is slow, and when the frequency is high, the operation of the object is fast.
[0048]
For example, in the case of the object state determination device 10 (associated with an automatic flushing device or the like) used in the men's urinal 21 or the like shown in FIG. 4, the person who is the target object normally walks (1 m / s) from the illustrated state. Stops after approaching the urinal at about), but then the person will slightly move his body in preparation for work.
[0049]
Then, the generation frequency of the Doppler signal in the above situation is as follows. That is, first, a Doppler signal when a person approaches approaches a frequency higher than a predetermined value. When the Doppler signal is stopped in front of the men's urinal, a low frequency is generated. Moreover, the approaching period and the period in which the urinal is stopped in front of the men's urinal are longer than a certain time.
[0050]
This change in frequency is a change in speed that can be considered in a predetermined time unit, and appears in the length of the approaching or moving away distance during a predetermined time (for example, one second). In other words, it can be said that the larger the amount of change in the count value (accumulated value) of the Doppler wave cycle counting unit 14 within the predetermined time, the faster the change.
[0051]
Therefore, when the frequency of the Doppler signal continues for a predetermined period or more for a predetermined period or more and then changes to a low frequency (including 0) for a predetermined period of time, it stops in front of the urinal for men. Can be estimated.
[0052]
Further, as described above, when the object approaches the Doppler sensor, the approach state continues continuously, and when the object stops before the Doppler sensor, the state of close approach and separation continues. Therefore, as another determination algorithm, the change state of the count value of the Doppler wave cycle counter 14 is monitored, and the count value decreases for a certain period of time, and thereafter, repeatedly increases and decreases within a relatively narrow predetermined range. Can be determined to be stopped, and the presence of an object (person) at that location can be detected.
[0053]
Of course, if the target object can be completely stopped, such as a vehicle, after the count value has decreased for a certain period, if the count value has not changed for a certain period, the object stops there. It can be determined that it exists in the state.
[0054]
As another mode of the state determination of the object in the state determination / control section 15, the passage of the object can be detected. That is, when a person passes, the person usually approaches the Doppler sensor 11 and then separates. Specifically, the count value stored in the Doppler wave cycle counting unit 14 is monitored, the count value decreases for a certain period of time (approaching), and thereafter, the count value increases (separation). In this case, it can be determined that the vehicle has passed. It should be noted that the determination of the increase / decrease is preferably made such that the change in the increase / decrease within a minute range is ignored, and the determination is made based on whether or not there is an increase / decrease tendency as a whole.
[0055]
Further, as another mode of the state determination of the object by the state determination / control section 15, the separation of the object can be detected. That is, from the count value of the Doppler wave cycle counting unit 14, although the moving distance of the target object can be obtained with high accuracy, for example, that the target object has departed from the object state determination device 10, and that it has been separated by more than a predetermined distance Cannot be accurately detected.
[0056]
Therefore, in the present embodiment, the motion analysis unit 12 detects that the target object has reached a predetermined reference position (reference point), and after detecting that the target object has reached this reference point, the Doppler wave cycle counting unit 14. If the count value of the target object increases, it can be determined that the target object has separated. Also, by resetting the count value of the Doppler wave cycle counting unit 14 with the arrival at the reference point as a trigger, when the count value exceeds a predetermined threshold value, the distance from the object state determination device 10 by a desired distance or more is reset. It can also be determined that it has been done. Of course, instead of resetting in this way, a similar determination can be made by storing and holding the count value when detecting that the vehicle has reached the reference point and calculating the difference between the stored value and the current count value. It can be performed.
[0057]
The following various algorithms can be used as the reference point calculation algorithm. Of course, the calculation algorithm of the reference point in the present invention is not limited to those listed below. In the present embodiment, the reference point detection algorithm is performed on the operation analysis unit 12 side. However, the present invention is not limited to this, and necessary information is given to the state determination / control unit 15, , The reference point may be detected, and a predetermined state determination may be performed. Furthermore, an independent reference point detection unit may be provided.
[0058]
* Detection using frequency change
Basically, it can be the same as the presence detection algorithm. That is, the operation speed of the target object can be detected based on the frequency at which the detection Doppler signal is generated. When the frequency is low, the operation of the object is slow, and when the frequency is high, the operation of the object is fast. Therefore, when a frequency equal to or higher than a predetermined frequency has been generated for a predetermined time and the state where the frequency has changed to a low frequency has continued for a predetermined time, that position can be set as a reference point. In this case, when the frequency suddenly decreases, it indicates that the object has stopped from the operating state, and the position of the reference point is further clarified.
[0059]
A specific device configuration for detecting the reference point using such a frequency can be, for example, as shown in FIG. That is, this example shows an embodiment in which the frequency measurement unit 17 is added to the object state determination device 10 having the configuration shown in FIG. The frequency measuring section 17 includes a pass amplifier 17a and a low-frequency amplifier 17b connected in series as shown in FIG. 5B, and can measure the frequency of the Doppler signal. More specifically, the Doppler wave output from the second mixer M2 is provided to the pass amplifier 17a of the frequency measurement unit 17. The passing amplifier 17a passes through the frequency band of the moving speed that the object can take, and passes through the passing amplifier 17a both when the moving speed is high and the frequency is high and when the moving speed is slow and the frequency is low. I do. The output of the pass amplifier 17a is provided to the low-frequency amplifier 17b and the operation analyzer 12 at the subsequent stage.
[0060]
The low-frequency amplifier 17b is set so as to pass only the low frequency when it comes near the above-mentioned reference point, and its output is given to the operation analysis unit 12.
[0061]
Thus, when the frequency of the Doppler signal is high while the object is moving, only the passing amplifier 17a has an output and cannot pass through the low-frequency amplifier 17b. When the object is stopped and the frequency of the arm Doppler signal is low, a signal is output from any of the passing amplifier 17a and the low-frequency amplifier 17b. Based on the state of the output signal, the motion analysis unit 12 determines whether the target has reached the reference point X.
[0062]
Specifically, it can be realized by an algorithm for executing the flowchart shown in FIG. Of course, it is not limited to this algorithm. That is, it is determined whether a frequency higher than a predetermined value is generated for a predetermined time (ST21). Here, whether or not the predetermined time has elapsed can be determined by an internal timer or the like. Further, whether or not the frequency is high can be determined based on whether or not a signal is output only from the pass amplifier 17a.
[0063]
Then, when the branch determination is Yes, it is determined whether the state changed to the low frequency has continued for a predetermined time (ST22). That is, the determination can be made based on whether signals are output from both the pass amplifier 17a and the low-frequency amplifier 17b. Then, if it is continuous for a predetermined time, the position is set as a reference point (ST23).
[0064]
Further, in the above example, the point at which the state of the object has stopped moving has been set as the reference point, but the fact that the object has started moving away from the predetermined position is not used as the reference point. Can be used as a reference point. For example, when a Doppler sensor is incorporated in a seat to detect that a person has risen from the seat, the person moves slowly while the person is sitting on the seat but moves fast when the person stands up. Therefore, when a fast motion of a certain level or more (the Doppler signal has a certain frequency or more) is detected, it can be used as a reference point. In this case, it can be effectively used for determining that the user has departed after moving a predetermined distance.
[0065]
This makes it possible to prevent accumulation of accumulated errors in counting when the stopped state is long, and to perform more reliable state determination of the target object as compared with the case where the point stopped from the operating state is used as the reference point. it can.
[0066]
Further, in the above-described embodiment, the output of the second mixer M2 is provided to the frequency measuring unit 17 composed of a filter, and the level of the frequency is determined there, but the output of the first mixer M1 is used. Needless to say, this may be applied (this is the same in other embodiments). Furthermore, similarly to the above-described presence detection function, the determination of the frequency level can be obtained from the change in the count value of the Doppler wave cycle counting unit 14 within a predetermined period. That is, in the embodiment shown in FIG. 1A, the information transmission is one-way, such as giving a control command (approach / separation) from the motion analysis unit 12 to the Doppler wave cycle counting unit 14. The present invention is not limited to this, and the information transmission is bidirectional. The operation analysis unit 12 reads the count value of the Doppler wave cycle counting unit 14 and determines whether or not the information is located at the reference point based on the change state of the count value. Can be determined.
[0067]
Thereby, in the case of FIG. 4, for example, a person advances to the front of the Doppler sensor (men's urinal) and stops, so that it can be determined as a reference point. The reference point is based on the fact that the approaching object stops at a predetermined position, and the predetermined position is used as the reference point, so after reaching the reference point, the object moves away. become. Therefore, after recognizing that the state has reached the reference point, if the count value of the Doppler wave cycle counting unit 14 increases, the state determination / control unit 15 can determine that the state has separated. Further, it can be determined from the amount of change in the count value that the vehicle has departed by a predetermined distance or more. At this time, when the count value is reset when the reference point is reached, if the count value exceeds a predetermined value, it can be determined that the target object is separated from the target by a predetermined distance or more. The determination of the state is the same when the reference point is detected by another method described below.
[0068]
Further, the function of detecting the reference point can be performed by the state determination / control unit 15. In this case, if the frequency measurement unit 17 is used, the frequency measurement unit 17 may be changed so that the output of the frequency measurement unit 17 shown in FIG. Of course, when the count value stored in the Doppler wave cycle counting unit 14 is used, a configuration similar to that of the block diagram shown in FIG. It can be handled by incorporating a function for executing the flowchart shown in FIG. When the state determination / control unit 15 determines that the state has deviated by a predetermined distance, as a series of processing algorithms from the detection of the reference point, for example, a flowchart shown in FIG. 7 is implemented. Incorporate functionality. Here, the “movement by a predetermined distance” in step 24 is the increment of the current count value with respect to the count value of the Doppler wave cycle counting unit 14 when the reference point is detected (0 when reset is applied). Is determined to be greater than or equal to a certain value.
[0069]
According to the object state determination device 10 configured to detect such a departure from the reference point as the state determination of the object, for example, the automatic flushing device of the urinal 21 for men shown in FIG. When the state determination device 10 is applied, the person who is the object approaches the urinal 21 for men from the position of P1, stops at the reference point of P2, and then separates. At this time, when it is detected that the reference point P2 has moved away from the reference point by a predetermined distance to the position P3, for example, the automatic flushing device is operated to flow water to the urinal 21 for men.
[0070]
Further, as shown in FIG. 8B, the Doppler sensor 11 of the object state determination device 10 is arranged on the bottom surface of the vehicle 31 toward the ground, which is the target, so that the vehicle 31 is jacked up for security. Detection (detection of a difference between the distance P1 before jacking up and the distance P2 after jacking up) can be performed. That is, as shown by a solid line in FIG. 8B, in a normal stop state, the distance from the ground, which is the target object, is constant at P1. Therefore, since there is no change, the frequency becomes 0 or a low value, and the count value of the Doppler wave cycle counting unit 14 hardly changes, so that it can be recognized as the reference point. In this state, when the vehicle 31 is jacked up and the distance P2 between the object state determination device 10 (Doppler sensor 11) and the ground is large, it can be determined that the object is relatively separated. Along with this, the control function of the state determination / control unit 15 performs a process of operating an alarm unit or informing a portable device or the like of the owner of a vehicle at a remote place by radio.
[0071]
When the object state determination device 10 is installed in the room of the vehicle 31, it can be applied to occupant determination. That is, when the occupant gets into the vehicle 31, a Doppler signal accompanying the movement is output at the beginning of the boarding. However, when the occupant gets on the seat and does not move greatly, the Doppler signal is output or not. However, the count value of the topler wave cycle counting unit 14 repeatedly increases and decreases within a minute range, so that the reference point X can be set. Thereafter, when the occupant gets off the vehicle 31, the count value of the Doppler wave cycle counting unit 14 increases, so that the state determination and control unit 15 can detect that the vehicle has separated, that is, the vehicle has got off. Along with this, the control function of the state determination / control unit 15 can perform various controls such as turning on the theft alarm device and locking the door of the vehicle.
[0072]
It should be noted that the processing algorithm after the above-described reference point detection can also perform the same processing when the reference point is detected by the following various algorithms.
[0073]
* Judgment based on the accumulated number of Doppler signal cycles (count value)
When the object stops after approaching the Doppler sensor, a Doppler signal is not output or a Doppler signal is generated due to slight fluctuation of a person, and the Doppler signal is repeatedly repeated in approaching and separating. In this case, if the number of Doppler signals generated is counted from the conditions for the generation of the Doppler signal and the approach / separation at that time, the motion of the person is averaged, and when the value is equal to or less than a predetermined value, it is determined that the operation is stopped and the reference point is determined. And can be stabilized. Similarly, when the count value becomes larger than a predetermined value on the departure side when deviating from the reference point, it can be determined that the departure from the reference point has occurred.
[0074]
That is, the count value of the Doppler wave cycle counting unit 14 is monitored, and when the number of accumulated cycles (count value) of the Doppler signal for each predetermined time becomes equal to or more than the predetermined value from the state in which it is equal to or less than the predetermined value, the object is set to the reference point. X can be determined to exist.
[0075]
When the object stops after approaching the Doppler sensor, a Doppler signal is not output or a Doppler signal is generated due to slight fluctuation of a person, and the Doppler signal is repeatedly repeated in approaching and separating. In this case, when the number of Doppler signals generated is counted from the conditions for the generation of the Doppler signal and the approach / separation at that time, the motion of the person is averaged, and when the value is equal to or less than a predetermined value, it is determined that the operation is stopped. Point X can be stabilized. Similarly, when the count value becomes larger than a predetermined value on the departure side when deviating from the reference point, it can be determined that the departure from the reference point has occurred.
[0076]
* Detection using the approaching / separating state
When the object approaches the Doppler sensor 11, the approach state continues continuously, and when the object stops before the Doppler sensor, the state of close approach and separation continues. For example, if a person stops in front of the Doppler sensor 11 in the state shown in FIGS. 4 and 8A, as described above, approaching and moving away from the required operation will be repeated finely. When the oscillation frequency of the Doppler sensor 11 is 24 GHz, the moving distance corresponding to one cycle of the Doppler signal required to determine the approach / separation is 0.62 cm, which can be sufficiently used for the determination. That is, in the separation determination after the approach determination, the person as the target stops in front of the Doppler sensor and can be used as a reference point.
[0077]
Note that, in the above example, the point that has departed after approaching is determined as the reference point. However, with such a configuration, the departure determination may be performed due to the movement of the target object (for example, the movement of the hand) during the approach. There is. For this reason, in the case where the vehicle is approaching as a whole even when the vehicle is momentarily or temporarily separated, it may be determined that the vehicle has not actually separated. Specifically, it is possible to determine that the separation has occurred on the condition that “the separation has occurred more than a predetermined amount”.
[0078]
In such a case, for example, in the example shown in FIG. 8A, a separation signal may be generated due to a movement of a hand or the like at a predetermined position while a person approaches the position from A to B, but the separation is temporary. Is not determined to be a separation. Then, after coming to the position of B, when the vehicle separates and reaches the point C, it is determined that the vehicle has separated. Since the actual reference point in this case is point B, the movement amount from B to C (the cumulative value of the distances of the continuous separation signals acquired from the Doppler wave cycle counting unit 14) is stored, and separation is determined. Sometimes an actual reference point can be calculated from the stored value. Thereby, an accurate separation distance from the point B of the current object can be calculated thereafter. Note that the point C here has a different meaning from P3 and is illustrated at the same position in FIG. 8 for convenience, but of course the actual distance is different.
[0079]
It should be noted that the departure is greater than or equal to the predetermined value when the value of the Doppler wave cycle counting unit 14 has been increasing for a certain period of time (in a tendency to increase), or the separation / approaching determination result output from the motion analysis unit 12 has a certain period It can be judged from the fact that it is "separation".
[0080]
* Judgment based on signal intensity of Doppler signal
The signal intensity of the Doppler signal increases as the object approaches the Doppler sensor. Therefore, a point where the state where the Doppler signal has the intensity equal to or higher than a predetermined value continues for a predetermined time or more can be set as the reference point. This may simply measure the time at which the intensity is higher than a predetermined value, or the signal intensity increases with approaching. It may be a point.
[0081]
In addition, when the object approaches the Doppler sensor 11, the Doppler signal intensity continuously increases. However, when the object stops before the Doppler sensor, the Doppler signal may not be detected. Alternatively, a point at which the current value increases to a predetermined value and rapidly decreases, or a point at which the current value disappears, may be used as the reference point.
[0082]
As a specific device configuration for realizing the reference point detection function in consideration of the signal strength, for example, it is possible to provide a signal strength measuring unit 16 as shown in FIG. That is, the output of the second mixer M2 is provided to the signal strength measurement unit 16, where the signal strength of the Doppler signal is obtained, and the obtained signal strength is provided to the operation analysis unit 12. The reference point detection function in the motion analysis unit 12 determines whether or not the above condition is satisfied, based on the signal strength of the acquired Doppler signal. When the condition is satisfied, the reference point is set.
[0083]
The reference point detection function based on the signal strength can also be performed by the state determination / control unit 15 by providing the output of the signal strength measurement unit 16 to the state determination / control unit 15. Then, in order to perform a series of processes for detecting a state in which the reference point is separated by a predetermined distance after the detection of the reference point, it is possible to incorporate a function for executing the flowchart shown in FIG.
[0084]
Note that the branching determination in step 31 does not presuppose that the Doppler signal cannot be detected and the signal strength drops sharply. However, this is because the Doppler signal is not output when the object is a person. It is almost impossible to stop completely. Therefore, in the case of an object that is completely stopped and the Doppler signal is not output, the branch determination in step 31 determines that the signal intensity suddenly decreases after a signal intensity of a certain level or more is detected for a predetermined time. It will be changed as appropriate.
[0085]
Also, even when the device is a person and stops near the reference point, as in the case of an automatic flushing device for a urinal for men, for example, a Doppler signal is generated by slight shaking of the person even in the stopped state. At the time of the occurrence, since the person is in the immediate vicinity of the Doppler sensor 11, the signal strength becomes maximum. If this state continues for a predetermined time, the reference point can be detected.
[0086]
Furthermore, as described later, when the state determination of the object finally performed detects that the object has approached a predetermined distance from the reference point, the signal strength at the time of approaching is the signal intensity at the reference point. Therefore, the signal strength at the reference point is not always the maximum. Therefore, the level of the signal strength equal to or higher than a certain value, which is the determination condition of step 31, is of course appropriately set in accordance with the type of detection target / state determination.
[0087]
Further, in the process of step 34, when the reference point position is further approached by a predetermined distance (the integrated value decreases), it is determined that the desired position between the reference point and the Doppler sensor 11 has been reached. When the user has moved a predetermined distance, it can be determined that the user has moved away, as in the above-described examples.
[0088]
Such an object state determination device 10 is a control signal from a state determination and control unit 15 when a certain distance is approached after detecting a Doppler signal of a predetermined level or more when automatically turning on an automatic light such as a front light upon detection of a person, for example. , The automatic light can be turned on. In this way, if there is a branch of a tree plant near the automatic light, the movement of the branch is detected by the wind and may be determined as a reference point, but the branch only shakes and does not approach beyond a certain distance. Malfunction can be prevented.
[0089]
In addition, as the lighting control of the automatic light when the vehicle departs from the reference point, for example, it is possible to control to turn on the light when the vehicle comes to the reference point and to turn off the light when detecting that the vehicle departs from the reference point by a predetermined distance. .
[0090]
In addition, automatic toilet seats in toilets open the toilet door and detect that the target person has entered, and automatically open the toilet seat, but if the toilet space is narrow, reflection from the door will occur. However, it is difficult to determine the reference point. In such a case, a case where a change in the signal intensity (signal level) of the Doppler signal occurs during a predetermined time is set as a reference point, and when the Doppler sensor approaches the Doppler sensor by a certain distance therefrom, the toilet seat may be opened.
[0091]
* Detection using Doppler signal strength and frequency
As described above, when an object approaches, a Doppler signal having a frequency equal to or higher than a predetermined frequency is generated. Then, if the distance to the object is short, the generated Doppler signal also becomes large, so that the Doppler signal when the object is in the immediate vicinity of the Doppler sensor has a signal strength of a predetermined level or more, and the frequency of the Doppler signal is It will be low. Therefore, by judging these conditions in combination, more accurate detection of the reference point can be performed.
[0092]
The specific configuration can be, for example, as shown in FIG. FIG. 11 is a diagram showing an embodiment in which a signal strength measurement unit 16 and a frequency measurement unit 17 are added to the object state determination device 10 having the configuration of FIG. The operation analysis unit 12 comprehensively determines whether or not it is a reference point according to the information acquired from the signal strength measurement unit 16 and the frequency measurement unit 17. As an example of this determination, it can be determined that the reference point has been reached only when the reference point is detected based on the frequency and the reference point is detected based on the signal strength. In addition to the above, various methods can be adopted, such as weighting both conditions, for example, making one of them main and making a judgment using the other as an auxiliary.
[0093]
By the way, after specifying the reference point of the object as described above, it is possible to calculate the relative distance from the reference point based on the number of occurrences of the Doppler signal and the approach / separation information. However, due to the influence of another moving object, a Doppler signal is generated even when the object is not moving, or the Doppler signal generated during the movement of the object is an accurate Doppler signal due to the influence of another moving object. There may be a case where counting cannot be performed.
[0094]
That is, for example, FIG. 12 is a plan view of the restroom, and the person A stops in front of the Doppler sensor 11 of the object state determination device 10 and after the reference point is determined, separates behind the person A. When the person B passes, the Doppler sensor 11 is affected by the movement of the person B, and a Doppler signal for determining the approach is generated. Further, when the person B passes behind the person A, A Doppler signal for determining the separation may be generated. Since the Doppler signal for which the approach / separation is determined has an adverse effect on the determination of the state of the person A, in such a case, for example, the approach signal after the reference point is determined may be ignored.
[0095]
Further, at this time, if only the Doppler signal having a frequency equal to or higher than the predetermined frequency detected by the frequency measuring unit 17 is detected as a malfunction signal, it is possible to reliably determine that the malfunction has occurred without detecting the influence of the fluctuation due to the stopped object. More preferred.
[0096]
Further, when the Doppler signals that are determined to approach are changed to the Doppler signals that are determined to be continuously separated, these signals may be ignored. That is, in the state as shown in FIG. 12, the person B passing behind the person A approaches the Doppler sensor 11 and, when passing the front of the Doppler sensor 11, reverses and moves away. That is, the vehicle continuously departs from the approach.
[0097]
Therefore, when the motion analysis unit 12 determines that the target object is present at the reference point and then determines that the object is continuously separated, the Doppler signal is determined to be a malfunction signal and the Doppler wave cycle counting unit 14 is controlled. be able to. When the Doppler signals for which the approach is determined are changed to the Doppler signals for which the separation is determined continuously, these signals may be ignored.
[0098]
In general use, it is often desired to detect the state of an object near the Doppler sensor 11 but not to detect a change at a slightly distant place. For example, there is an exhibit commentary device that makes an announcement when a person approaches an exhibit, an automatic toilet seat, an automatic light, an automatic door, etc., which operate when a person approaches or sits down. In these cases, it is preferable that a person who is located at a distance more than a predetermined distance is not detected. Thus, the approach or separation of a person can be identified based on the intensity of the Doppler signal.
[0099]
However, the signal intensity may be different depending on the size of the target object (for example, an adult or a child) or the influence of a surrounding reflector. In addition, the emission of the Doppler wave from the horn antenna HA spreads as the distance increases, so that a farther object is detected in a wider range. Therefore, even for a Doppler signal having a signal strength equal to or higher than a predetermined level, a distant motion is detected in a wider range than a near motion, which causes a malfunction.
[0100]
In order to solve this problem, at the time of counting, for example, in a configuration in which the signal strength measurement unit 16 shown in FIG. 9 is added, malfunctions can be eliminated by appropriately modifying the processing algorithm of the operation analysis unit 12 and the like. That is, the motion analysis unit 12 can cope with this by performing weighting based on the signal strength.
[0101]
Specifically, the signal strength of the Doppler signal is classified into, for example, five levels, and weighting is performed from 1 to 5 as the signal strength increases. Then, the weight of the signal strength when the Doppler signal occurs for one cycle is accumulated. In other words, in each of the above-described embodiments, the motion analysis unit 12 gives the approach / separation determination result to the Doppler wave cycle counting unit 14, and when one cycle of the Doppler signal occurs, if the determination result is a separation, the total is counted. The numerical value is set to “+1”, and in the case of separation, it is set to “−1”. In other words, since the weight of the signal strength was always “1”, the count value increased or decreased by one.
[0102]
On the other hand, in the present embodiment, the increase / decrease amount of one count value when one cycle of the Doppler signal occurs is any one of “1 to 5” according to the weight of the signal strength. Specifically, when one cycle of the Doppler signal occurs, the weight of the signal strength is “+5”, and when the signal is an approach signal, the count value is “−5”. I do. Similarly, when the weight of the signal strength is “1”, “−1” is set for the approach signal, and “+1” is set for the departure signal. Of course, the same applies when the weight of the signal strength is “2”, “3”, or “4”.
[0103]
In this way, the influence of a distant movement is small and the influence of a close movement is large. For example, in an automatic flushing device for a men's urinal, when a distance from a reference point is detected and flushing is performed, as shown in FIG. Will be higher.
[0104]
Therefore, as in the present embodiment, malfunctions can be reduced by weighting the movement of a person who is relatively far away and the movement of an object in the immediate vicinity of the urinal for men. In addition, when the reference point is specified, weighting is performed in the same manner as described above, so that malfunction can be reduced.
[0105]
According to each of the above-described embodiments, the situation of the target object can be accurately determined. Therefore, the automatic flushing device, the automatic toilet seat, the automatic light that lights up when a person approaches, the jack-up detection of the vehicle, the occupant determination, etc. For devices that determine the state of an object based on a change in the distance to the object in the security field, etc., and devices that detect the presence of an object such as an automatic door or parking of a car in a parking lot based on the change in distance Can also be applied.
[0106]
By accumulating the number of Doppler wave generation cycles at the time of approach / separation and movement of the target object, it is possible to determine an accurate change in distance from the target object, and also determine the absence or stop of the target object. be able to.
[0107]
【The invention's effect】
According to the present invention, it is possible to accurately detect a state of an object such as presence, passage, movement from a predetermined position, and the like based on the output of the Doppler sensor. That is, the moving distance of the object can be determined from the count value stored in the Doppler wave cycle counting means, and the state of the object can be accurately determined accordingly. In addition, by increasing the resolution of the distance without complicating the circuit, the state of the object can be determined more reliably.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a phase relationship at the time of approach / separation of two mixer outputs shown in FIG. 1;
FIG. 3 is a flowchart illustrating an operation example of the object state determination device in FIG. 1;
FIG. 4 is a diagram illustrating an operation.
FIG. 5A is a diagram illustrating an embodiment in which a frequency measuring unit is added to the object state determination device having the configuration of FIG. 1A.
FIG. 2B is a diagram illustrating a configuration of a frequency measurement unit.
FIG. 6 is a flowchart illustrating an operation example of the object state determination device in FIG. 5;
FIG. 7 is a flowchart illustrating an operation example of the object state determination device in FIG. 5;
FIG. 8A is an explanatory diagram of a men's restroom.
(B) is an explanatory view of the jack-up detection of the vehicle security in which the Doppler sensor is arranged facing the ground.
FIG. 9 is a diagram showing an embodiment in which a signal strength measuring unit is added to the object state determination device having the configuration of FIG. 1A.
FIG. 10 is a flowchart illustrating an operation example of the presence detection device in FIG. 9;
11 is a diagram illustrating an embodiment in which a signal strength measuring unit and a signal strength measuring unit are added to the object state determination device having the configuration of FIG. 1A.
FIG. 12 is an explanatory plan view of a men's restroom.
[Explanation of symbols]
10 Object state determination device
11 Doppler sensor
12 Motion analysis unit
13 Doppler wave cycle detector
14 Doppler wave cycle counting section
15 Status judgment / control unit
16 Signal strength measurement section
17 Frequency measurement unit
21 urinals for men
31 vehicle
HA Horn Antenna
M1, M2 First and second mixers
L. O. Local oscillator

Claims (14)

A Doppler sensor having a plurality of mixers,
Operation analysis means for analyzing the movement of the object from the outputs of the plurality of mixers,
Doppler wave cycle detection means for detecting the occurrence of a Doppler wave based on the output of any of the plurality of mixers,
An output of the Doppler wave cycle detection means, a Doppler wave cycle counting means for counting a Doppler wave generation cycle from an output of the operation analysis means,
An object state determining device, comprising: a state determining unit that determines a state of the object based on at least an output from the Doppler wave cycle counting unit. 2. The object state determination device according to claim 1, wherein the motion analysis unit determines approach or separation based on outputs from at least two of the plurality of mixers. 3. The object state determination device according to claim 1, wherein the state determination unit detects the presence of the object from a change in a count value stored in the Doppler wave cycle counting unit. 4. . The said state determination means detects passage of the said object from the change of the count value stored in the said Doppler wave cycle counting means, The Claim 1 characterized by the above-mentioned. Object state determination device. Providing signal strength determination means for determining the signal strength of the Doppler signal based on the output from at least one of the mixers,
The object state determination device according to any one of claims 1 to 4, wherein the counting by the Doppler wave cycle counting unit is performed in consideration of an output of the signal intensity determination unit. Reference point detection means for detecting that the object has reached a predetermined reference point,
The object according to any one of claims 1 to 5, wherein the state determination unit determines a state of the target object from an amount of change in a count value of the Doppler wave cycle counting unit from the reference point. State determination device. Providing frequency measuring means for determining the generation frequency of the Doppler signal,
7. The reference point detection unit according to claim 6, wherein the output of the frequency measurement unit determines that an object is present at the reference point when a predetermined frequency change occurs within a predetermined time. Object state determination device. Providing signal strength detection means for detecting the signal strength of the Doppler signal,
The reference point detection means determines that an object is present at the reference point when a state where the signal strength is equal to or higher than a predetermined value continues for a predetermined time based on an output of the signal strength detection means. The object state determination device according to claim 6 or 7, wherein 9. The method according to claim 6, wherein the reference point detection unit determines that the target object is present at the reference point when the target object is reversed from the approach state to the separated state. An object state determination device according to claim 1. The reference point detecting means determines that an object is present at the reference point when a change in a count value for each predetermined time in the Doppler wave cycle counting means is equal to or less than a predetermined value. 10. The object state determination device according to any one of 6 to 9. The reference point detection means, from a state in which the change in the count value for each predetermined time in the Doppler wave cycle counting means is less than or equal to a predetermined value, when the target object is present at the reference point when it exceeds a predetermined value The object state determination device according to any one of claims 6 to 9, wherein the determination is performed. After the reference point detecting means determines that the target object is present at the reference point, if the motion analysis means detects the approach of the target object, the Doppler signal that is the source of the detection is determined to be a malfunction signal. The object state determination device according to any one of claims 6 to 11, wherein the device controls the Doppler wave cycle counting means. After the reference point detecting means determines that the object is present at the reference point, if the motion analysis means detects that the object has continuously approached and then separated, the detection of the 13. The object state determining apparatus according to claim 3, wherein the original Doppler signal is determined as a malfunction signal and the Doppler wave cycle counting means is controlled. 14. The object state determination device according to claim 1, further comprising a control unit that controls a predetermined device based on a determination result of the state determination unit.

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