JP2015219884A - Monitoring device, monitoring system, and monitoring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitoring device, monitoring system, and monitoring method, which suppress monitoring errors and provide improved detection accuracy in a configuration for monitoring human movement in a predetermined area using a radio wave.SOLUTION: A monitoring device includes; a plurality of detection antennas for receiving a radio wave transmitted from a transmitter located in a predetermined area; a monitoring unit which performs a monitoring process for monitoring human movement in the predetermined area based on the radio wave received by the detection antennas; and a radio wave analysis unit which generates information on whether the monitoring process can be performed by the monitoring unit based on the radio wave received by at least one of the detection antennas, according to which the monitoring unit may or may not perform the monitoring process.

Description

  The present invention relates to a monitoring device, a monitoring system, and a monitoring method, and more particularly, to a monitoring device, a monitoring system, and a monitoring method that monitor human actions based on radio waves.

  Intrusion detection devices that detect human movement in a predetermined area such as a room have been developed. As an example of the intrusion detection method, for example, “Study on indoor intruder detection by UWB-IR”, Teijihashi Koji et al., IEICE Transactions B, Vol. 97, pp. 97-10000, January 1, 2007 (Non-Patent Document 1) discloses a method using a propagation delay profile, that is, a power delay profile, based on UWB-IR (Ultra Wide Band-Impulse Radio).

  However, in the method described in Non-Patent Document 1, interference with other wireless services becomes a problem because a wideband signal is used, and because the received signal power is used, it is affected by indoor multipath fading, The detection accuracy may deteriorate.

  As a technique for solving such a problem, for example, Japanese Patent Laid-Open No. 2008-216152 (Patent Document 1) discloses the following configuration. That is, the event detection device calculates an eigenvector, that is, an arrival angle distribution based on the received signal of each array antenna, and calculates an inner product value of the eigenvector and a normal eigenvector as a comparison reference. Then, the event detection device detects an event, that is, an intruder, based on a comparison result between the inner product value and a predetermined threshold value.

"Study on indoor intruder detection by UWB-IR" Terasaka Junji et al., IEICE Transactions Journal B, Vol. 97-100, January 1, 2007

JP 2008-216152 A

  However, in a predetermined area such as a room, there may be a case where not only an intrusion detection radio wave transmitted from a predetermined transmitter, but also an intrusion detection radio wave transmitted from another device is present.

  For example, when the event detection device performs detection processing based on a radio wave received during a period in which no radio wave is transmitted from the transmitter, that is, a radio wave transmitted from another device, the event detection device Even in a situation where a human is not operating, there is a possibility of erroneous detection that a human is operating.

  In order to prevent such erroneous detection, for example, a configuration in which a radio wave is transmitted from a transmitter using a receiving module provided separately from the event detection device is conceivable. In this case, the receiving module receives incoming radio waves, determines whether radio waves are being transmitted from the transmitter based on the received radio waves, and sends the determination result to the event detection device, for example, by wire. Send.

  As a result, the event detection device can recognize the period during which radio waves are transmitted from the transmitter based on the determination result of the receiving module. Can be used for detection processing.

  However, for example, when the radio wave from the transmitter received by the receiving module is significantly attenuated due to the influence of multipath fading, the receiving module can determine whether or not the radio wave is being transmitted from the transmitter. become unable.

  In this case, for example, even if the quality of the radio wave received by itself is good, the event detection device cannot recognize the period during which radio waves are transmitted from the transmitter. A correct detection result cannot be obtained.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to suppress monitoring errors and improve monitoring accuracy in a configuration in which human actions in a predetermined area are monitored using radio waves. It is an object to provide a monitoring device, a monitoring system, and a monitoring method.

  (1) In order to solve the above-described problem, a monitoring device according to an aspect of the present invention includes a plurality of detection antennas that receive radio waves transmitted from a transmitter disposed in a predetermined area, and each of the detection antennas. Based on the radio wave received by at least one of a monitoring unit that performs a monitoring process for monitoring human movements in the predetermined area based on the radio wave received by the detection antenna A radio wave analysis unit that creates information on whether the monitoring unit can execute the monitoring process, and the monitoring unit executes the monitoring process based on the information.

  (6) In order to solve the above-described problem, a monitoring system according to an aspect of the present invention includes a transmitter that is disposed in a predetermined area and transmits radio waves, and a monitoring device, and the monitoring device includes the transmitter. A plurality of detection antennas that receive the radio waves transmitted from the monitoring unit, and a monitoring unit that performs a monitoring process for monitoring human actions in the predetermined area based on the radio waves received by the detection antennas; A radio wave analysis unit that creates information on whether or not the monitoring process can be performed by the monitoring unit based on the radio wave received by at least one of the detection antennas, and the monitoring unit includes: The monitoring process is executed based on the information.

  (7) In order to solve the above problems, a monitoring method according to an aspect of the present invention includes a step of receiving radio waves transmitted from a transmitter arranged in a predetermined area at a plurality of detection antennas, and each of the detections A step of creating information on whether or not to execute a monitoring process for monitoring a human operation in the predetermined area based on the radio wave received by at least one of the antennas for detection, and by each of the detection antennas Executing the monitoring process based on the received radio wave based on the information.

  The present invention can be realized not only as a monitoring apparatus including such a characteristic processing unit, but also as a method using such characteristic processing as a step, or a program for causing a computer to execute such a step. Can be realized. Further, it can be realized as a semiconductor integrated circuit that realizes part or all of the monitoring device.

  ADVANTAGE OF THE INVENTION According to this invention, in the structure which monitors the human motion in a predetermined area using an electromagnetic wave, the monitoring error can be suppressed and the monitoring precision can be improved.

FIG. 1 is a diagram showing a configuration of a monitoring system according to the first embodiment of the present invention. FIG. 2 is a diagram illustrating an example of information included in a radio wave transmitted from a transmitter in the monitoring system according to the first embodiment of the present invention. FIG. 3 is a diagram illustrating the configuration of the receiver according to the first embodiment of the present invention. FIG. 4 is a sequence defining a procedure for calculating a spatial feature amount in the monitoring system according to the first embodiment of the present invention. FIG. 5 is a diagram illustrating a configuration of a receiver according to the second embodiment of the present invention. FIG. 6 is a diagram illustrating a configuration of a receiver according to the third embodiment of the present invention. FIG. 7 is a diagram illustrating a configuration of a receiver according to the fourth embodiment of the present invention. FIG. 8 is a diagram illustrating a configuration of a receiver according to the fifth embodiment of the present invention.

  First, the contents of the embodiment of the present invention will be listed and described.

  (1) A monitoring device according to an embodiment of the present invention includes a plurality of detection antennas that receive radio waves transmitted from transmitters arranged in a predetermined area, and the radio waves received by the detection antennas. Based on the radio wave received by at least one of the monitoring unit that performs monitoring processing for monitoring human movement in the predetermined area and the detection antennas, the monitoring by the monitoring unit A radio wave analysis unit that creates information regarding whether or not the process can be executed, and the monitoring unit executes the monitoring process based on the information.

  With such a configuration, it is possible to determine a period during which radio waves are transmitted from the transmitter based on radio waves received by the detection antenna. Thus, for example, in a configuration in which the period is determined based on radio waves received by another antenna provided separately from the detection antenna, even if the quality of radio waves received by the detection antenna is good When the quality of the radio wave received by the other antenna is poor, it is possible to avoid the situation in which the period cannot be determined and a correct monitoring result cannot be obtained. Therefore, in a configuration in which human motion in a predetermined area is monitored using radio waves, monitoring errors can be suppressed and monitoring accuracy can be improved.

  (2) Preferably, the monitoring apparatus further includes an antenna selection unit that selects one or a plurality of the detection antennas from the detection antennas, and the radio wave analysis unit is selected by the antenna selection unit. The information is created based on the radio wave received by the detection antenna.

  With such a configuration, for example, even if the period cannot be determined based on the radio wave received at the detection antenna due to poor quality of the radio wave received at a detection antenna, The period can be determined using radio waves received by the antenna.

  (3) Preferably, the monitoring apparatus further includes a combining unit that combines the radio waves received by at least any two of the detection antennas, and the radio wave analysis unit includes: The information is created based on the radio wave synthesized by the synthesis unit.

  With such a configuration, since the quality of the signal used for the determination of the period can be improved, the period can be determined more accurately.

  (4) Preferably, the radio wave analysis unit creates the information for each radio wave based on the radio waves received by at least any two of the detection antennas. The monitoring unit executes the monitoring process based on each piece of information.

  With such a configuration, it is possible to more accurately determine the period using the information created for each received radio wave from a plurality of antennas.

  (5) Preferably, the monitoring device further includes an analysis antenna that receives the radio wave transmitted from the transmitter, and the radio wave analysis unit is based on the radio wave received by the analysis antenna. The information is generated, and the information is generated based on the radio wave received by at least one of the detection antennas when a reception state of the radio wave by the analysis antenna satisfies a predetermined condition .

  With such a configuration, for example, when the quality of radio waves received at the analysis antenna deteriorates, the antenna used for the determination of the period can be switched from the analysis antenna to the detection antenna. Judgment of the period can be made.

  (6) A monitoring system according to an embodiment of the present invention includes a transmitter that is disposed in a predetermined area and transmits radio waves, and a monitoring device, and the monitoring device transmits the radio waves transmitted from the transmitter. Of the plurality of detection antennas to be received, a monitoring unit that performs a monitoring process for monitoring a human operation in the predetermined area based on the radio waves received by each of the detection antennas, A radio wave analysis unit that creates information on whether or not the monitoring process can be performed by the monitoring unit based on the radio wave received by at least one of the monitoring unit, the monitoring unit based on the information Execute the process.

  With such a configuration, it is possible to determine a period during which radio waves are transmitted from the transmitter based on radio waves received by the detection antenna. Thus, for example, in a configuration in which the period is determined based on radio waves received by another antenna provided separately from the detection antenna, even if the quality of radio waves received by the detection antenna is good When the quality of the radio wave received by the other antenna is poor, it is possible to avoid the situation in which the period cannot be determined and a correct monitoring result cannot be obtained. Therefore, in a configuration in which human motion in a predetermined area is monitored using radio waves, monitoring errors can be suppressed and monitoring accuracy can be improved.

  (7) A monitoring method according to an embodiment of the present invention includes a step of receiving radio waves transmitted from a transmitter arranged in a predetermined area at a plurality of detection antennas, and at least one of the detection antennas. A step of creating information on whether or not to execute a monitoring process for monitoring a human operation in the predetermined area based on the radio wave received by the one, and based on the radio wave received by each of the detection antennas Executing the monitoring process based on the information.

  By such a method, it is possible to determine a period during which radio waves are transmitted from the transmitter based on the radio waves received by the detection antenna. Thus, for example, in a configuration in which the period is determined based on radio waves received by another antenna provided separately from the detection antenna, even if the quality of radio waves received by the detection antenna is good When the quality of the radio wave received by the other antenna is poor, it is possible to avoid the situation in which the period cannot be determined and a correct monitoring result cannot be obtained. Therefore, in a configuration in which human motion in a predetermined area is monitored using radio waves, monitoring errors can be suppressed and monitoring accuracy can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated. Moreover, you may combine arbitrarily at least one part of embodiment described below.

<First Embodiment>
[Configuration and basic operation]
FIG. 1 is a diagram showing a configuration of a monitoring system according to the first embodiment of the present invention.

  With reference to FIG. 1, the monitoring system 100 includes a transmitter 10 and a receiver (monitoring device) 11. The transmitter 10 and the receiver 11 are installed in a predetermined area to be warned, here, for example, an area 5 which is a warehouse.

  The transmitter 10 transmits a radio wave including a frame to the receiver 11 in accordance with, for example, the ZigBee method standardized as IEEE 802.15.4. This radio wave is, for example, a 2.4 GHz band radio signal.

  The receiver 11 is an array type radio wave sensor, includes a plurality of antennas, and realizes a human action monitoring function in the area 5 by using a change in the propagation state of the radio wave transmitted from the transmitter 10. Specifically, the radio wave transmitted from the transmitter 10 is reflected, transmitted, or diffracted by a wall, an obstacle, or a person in the area 5 and reaches the receiver 11. The radio wave transmitted from the transmitter 10 may reach the receiver 11 directly without being reflected.

  The receiver 11 calculates a spatial feature amount indicating the state of the area 5 based on each radio wave received by each antenna included in the receiver 11, and monitors a human action in the area 5 based on the calculated spatial feature amount. .

  FIG. 2 is a diagram illustrating an example of information included in a radio wave transmitted from a transmitter in the monitoring system according to the first embodiment of the present invention.

  Referring to FIG. 2, a frame transmitted from transmitter 10 includes, for example, a preamble and SFD (Start of Frame Delimiter) indicating the start of the frame, an ID indicating a transmission source, and a payload which is a data body. CRC (Cyclic Redundancy Check) which is error detection data used for error detection.

  FIG. 3 is a diagram illustrating the configuration of the receiver according to the first embodiment of the present invention.

  Referring to FIG. 3, receiver 11 includes detection antennas 21A, 21B, 21C, and 21D, a duplexer (DIV) 22, a receiver 23, an oscillator 24, a branch circuit 25, and a radio wave analysis unit. 26, a buffer unit 27, and a monitoring unit 28. Hereinafter, each of the detection antennas 21A, 21B, 21C, and 21D is also referred to as a detection antenna 21.

  The receiving unit 23 includes four sets of a band pass filter (BPF) 61, a low noise amplifier 62, a quadrature demodulator 63 and an A / D converter (ADC) 64 corresponding to each detection antenna 21.

  Each detection antenna 21 converts the radio wave received by itself into an electrical signal and outputs it. The duplexer 22 is connected to the detection antenna 21 </ b> A, branches the output signal of the detection antenna 21 </ b> A, and outputs the branched signal to the bandpass filter 61 and the radio wave analysis unit 26.

  The radio wave analysis unit 26 creates information on whether or not the monitoring process by the monitoring unit 28 can be performed (hereinafter also referred to as execution propriety information) based on the radio wave from the transmitter 10 received by the detection antenna 21A.

  Specifically, for example, the radio wave analysis unit 26 analyzes a signal received from the detection antenna 21 and, based on the analysis result, information for controlling each set of A / D converters 64 and the buffer unit 27. create.

  More specifically, the radio wave analysis unit 26 demodulates the output signal of the detection antenna 21A received via the duplexer 22, and converts the demodulated signal, which is an analog signal, into a digital signal Da.

  The radio wave analysis unit 26 analyzes the converted digital signal Da and detects the SFD included in the digital signal Da. When the radio wave analysis unit 26 detects the SFD, the radio wave analysis unit 26 generates frame start information indicating that the transmission of the radio wave including the frame from the transmitter 10 is started, and outputs the frame start information to the A / D converters 64 and the buffer unit 27 of each set. To do.

  In addition, the radio wave analysis unit 26 analyzes the converted digital signal Da and detects a CRC included in the digital signal Da. The radio wave analysis unit 26 uses the detected CRC to detect an error in a frame including the CRC, so that the radio wave transmitted from the transmitter 10 and received by the detection antenna 21A is interfered with by other radio waves. Determine whether or not.

  Specifically, the radio wave analysis unit 26 determines that the radio wave from the transmitter 10 has received interference from other radio waves when detecting an error in the frame, and the transmitter 10 when no error is detected. It is determined that the radio wave from was not subject to interference from other radio waves.

  When the radio wave analysis unit 26 determines that the radio wave from the transmitter 10 has not been interfered with, the radio wave analysis unit 26 creates non-interference information and outputs it to the A / D converter 64 and the buffer unit 27 of each set. On the other hand, when the radio wave analysis unit 26 determines that interference has occurred, the radio wave analysis unit 26 creates interference information and outputs it to the A / D converters 64 and the buffer unit 27 of each set.

  In each group in the receiving unit 23, the bandpass filter 61 attenuates a component outside a predetermined frequency band among the frequency components of the output signal of the corresponding detection antenna 21. The low noise amplifier 62 amplifies and outputs the signal that has passed through the band pass filter 61.

  The oscillator 24 generates a local signal and outputs it to the branch circuit 25. Branch circuit 25 outputs the local signal received from oscillator 24 to each set of quadrature demodulator 63.

  The quadrature demodulator 63 multiplies the output signal of the low noise amplifier 62 by the local signal received from the oscillator 24 via the branch circuit 25, thereby performing, for example, quadrature demodulation on the signal received from the low noise amplifier 62 and the baseband band. Are converted to I and Q signals and output to the A / D converter 64.

  When the A / D converter 64 receives the frame start information from the radio wave analysis unit 26, the A / D converter 64 converts the I signal and the Q signal received from the quadrature demodulator 63 into the digital signal Ds and outputs the digital signal Ds to the buffer unit 27. Start.

  When receiving the frame start information from the radio wave analysis unit 26, the buffer unit 27 starts storing the digital signal Ds output from the A / D converter 64.

  When the A / D converter 64 receives non-interference information or interference information from the radio wave analysis unit 26, the A / D converter 64 converts the I signal and Q signal received from the quadrature demodulator 63 into a digital signal Ds, and buffers the digital signal Ds. The output to the unit 27 is stopped.

  When the buffer unit 27 receives the non-interference information from the radio wave analysis unit 26, the buffer unit 27 stops storing the new digital signal Ds and outputs the stored digital signal Ds to the monitoring unit 28. Further, the buffer unit 27 outputs the digital signal Ds to the monitoring unit 28 and then erases the stored digital signal Ds.

  On the other hand, when receiving the interference information from the radio wave analysis unit 26, the buffer unit 27 stops storing the new digital signal Ds and deletes the stored digital signal Ds without outputting it.

  The monitoring unit 28 performs a monitoring process for monitoring a human operation in the area 5 based on the radio wave from the transmitter 10 received by each detection antenna 21.

  Specifically, the monitoring unit 28 receives the digital signal Ds from the buffer unit 27, calculates the “eigenvector” described in Patent Document 1, for example, based on the digital signal Ds, and calculates the spatial feature amount based on the calculation result. calculate.

For example, if the eigenvector at the start of monitoring is the eigenvector vno and the eigenvector at the observation time t is the eigenvector vob (t), the spatial feature P (t) is expressed by the following equation (1). That is, the spatial feature amount P (t) is obtained by the inner product of the eigenvector vno and the eigenvector vob (t).
P (t) = vno · vob (t) (1)

  For example, when the state of the area 5 at the observation time t is the same as that at the start of monitoring, the eigenvector vno and the eigenvector vob (t) are the same, and thus the spatial feature P (t) is 1. On the other hand, for example, when a human is moving at the observation time t in the area 5, the eigenvector vob (t) changes with respect to the eigenvector vno, so that the spatial feature P (t) decreases from 1, for example 0. 9

  From this, the receiver 11 can be used as an intrusion detection device in the area 5 or a human watching device in the area 5, for example.

  Specifically, when the receiver 11 is used as an intrusion detection device, the monitoring unit 28 of the receiver 11 generates, for example, a human motion in a predetermined area based on the calculated spatial feature P (t). Detect.

  Specifically, the closer the spatial feature P (t) is to “1”, the closer to the normal state where no person is present in the area 5. Therefore, the monitoring unit 28 determines that a human has entered the area 5 when the spatial feature P (t) is less than a predetermined threshold, for example, “0.9”.

  On the other hand, when the receiver 11 is used as a monitoring device, the monitoring unit 28 of the receiver 11 indicates that there is no or little human action in the area 5 based on the calculated spatial feature P (t), for example. Detect.

  Specifically, for example, the monitoring unit 28 monitors whether there is a person who has not moved for a predetermined time or more due to an abnormality such as a heart attack in the area 5. In this case, the area 5 is, for example, an area where one or a plurality of humans perform an operation such as walking during normal times.

  As the spatial feature P (t) is smaller than “1”, the state of the predetermined area at the observation time t is closer to the normal state in which one or more people are moving.

  Therefore, the monitoring unit 28 determines that there is no or little human action in the predetermined area when the state in which the spatial feature amount P (t) is equal to or greater than the predetermined threshold continues for a predetermined time or longer.

  Specifically, assuming that the predetermined threshold value is “0.9”, the monitoring unit 28 determines that the human motion in the predetermined area is smaller when the spatial feature P (t) is smaller than “0.9”. It is determined that there is a normal state. On the other hand, when the state where the spatial feature P (t) is “0.9” or more continues for a predetermined time or longer, the monitoring unit 28 determines that there is no human activity or a small abnormal state in the predetermined area. .

  The receiver 11 is not limited to the configuration including the four detection antennas 21, but may be any configuration including two or more detection antennas 21.

[Operation]
The receiver 11 includes a computer, and an arithmetic processing unit such as a CPU in the computer reads a program including a part or all of each step of the following sequence from a memory (not shown) and executes the program. The program of this apparatus can be installed from the outside. Each program of this apparatus is distributed in a state stored in a recording medium.

  FIG. 4 is a sequence defining a procedure for calculating a spatial feature amount in the monitoring system according to the first embodiment of the present invention.

  The monitoring unit 28 performs a monitoring process based on the frame start information, the non-interference information, and the interference information that are execution enable / disable information.

  Specifically, referring to FIG. 4, first, transmitter 10 starts transmitting a radio wave including a frame (step S12).

  In the receiver 11, each detection antenna 21 converts the radio wave received from the transmitter 10 into an electrical signal and outputs it to the receiving unit 23. The detection antenna 21 </ b> A also outputs an electrical signal to the radio wave analysis unit 26 via the duplexer 22.

  The radio wave analysis unit 26 converts the output signal of the detection antenna 21A into a digital signal Da. When the radio wave analysis unit 26 analyzes the converted digital signal Da and detects an SFD (step S13), the radio wave analysis unit 26 outputs frame start information to each A / D converter 64 and the buffer unit 27 (step S14).

  Next, each A / D converter 64 receives frame start information from the radio wave analysis unit 26 and starts outputting the digital signal Ds (step S15).

  Further, the buffer unit 27 receives the frame start information from the radio wave analysis unit 26 and starts storing the digital signal Ds output from the A / D converter 64 (step S16).

  Next, the transmitter 10 completes the transmission of the radio wave including the frame (step S17). When the radio wave analysis unit 26 analyzes the digital signal Da and detects the CRC included in the last field of the frame (step S18), the radio wave analysis unit 26 recognizes that the reception of the frame in the receiver 11 is completed and uses the CRC. Then, frame error detection is performed (step S19).

  When the radio wave analysis unit 26 determines that there is no error in the frame, the radio wave analysis unit 26 outputs non-interference information to each A / D converter 64 and the buffer unit 27 (step S20).

  Next, each A / D converter 64 receives no-interference information from the radio wave analysis unit 26 and stops outputting the digital signal Ds (step S21).

  Further, the buffer unit 27 receives no-interference information from the radio wave analysis unit 26, stops storing the digital signal Ds (step S22), and outputs the stored digital signal Ds to the monitoring unit 28 (step S23). Then, the buffer unit 27 erases the stored digital signal Ds (step S24).

  Next, the monitoring unit 28 calculates an eigenvector based on the digital signal Ds received from the buffer unit 27 (step S25), and calculates a spatial feature amount based on the calculated eigenvector (step S26). That is, the monitoring unit 28 calculates the spatial feature amount when each A / D converter 64 and the buffer unit 27 receives the non-interference information from the radio wave analysis unit 26.

  On the other hand, the radio wave analysis unit 26 detects a frame error (step S19), and outputs interference information to each A / D converter 64 and the buffer unit 27 when it is determined that there is an error.

  The A / D converter 64 receives interference information from the radio wave analysis unit 26 and stops outputting the digital signal Ds.

  Further, the buffer unit 27 receives the interference information from the radio wave analysis unit 26 and erases the stored digital signal Ds without outputting it.

  Therefore, the monitoring unit 28 does not calculate a spatial feature amount when each A / D converter 64 and the buffer unit 27 receives interference information from the radio wave analysis unit 26.

  By the way, for example, it is assumed that the receiver 11 receives a radio wave from another device during a period when the radio wave is not transmitted from the transmitter 10 and calculates an eigenvector based on the received radio wave. In such a case, the newly calculated eigenvector may be significantly different from the eigenvector calculated in advance based on the radio wave from the transmitter 10, so that the receiver 11 is operated by humans in the area 5. Even if it is not in the situation, there is a possibility of erroneous detection that a human is operating.

  In order to prevent such erroneous detection, for example, a configuration in which a radio wave is transmitted from the transmitter 10 using a receiving module provided separately from the receiver 11 can be considered. In this case, the receiving module receives incoming radio waves, determines whether or not radio waves are transmitted from the transmitter 10 based on the received radio waves, and transmits the determination result to the receiver 11 by wire, for example. To do.

  As a result, the receiver 11 can recognize the period during which radio waves are transmitted from the transmitter 10 based on the determination result of the receiving module, and therefore selectively receives radio waves received by itself during the period. Can be used for monitoring.

  However, for example, when the radio wave from the transmitter 10 received by the reception module is significantly attenuated due to the influence of multipath fading, the reception module determines whether or not the radio wave is transmitted from the transmitter 10. Can not be.

  In this case, for example, even if the quality of the radio wave received by the receiver 11 is good, the receiver 11 cannot recognize the period during which the radio wave is transmitted from the transmitter 10. The monitoring result cannot be obtained.

  On the other hand, in the receiver 11 which is the monitoring apparatus according to the first embodiment of the present invention, the plurality of detection antennas 21 receive radio waves transmitted from the transmitter 10 arranged in the area 5. . The monitoring unit 28 performs a monitoring process for monitoring a human operation in the area 5 based on the radio wave from the transmitter 10 received by each detection antenna 21. The radio wave analysis unit 26 performs execution availability information, which is information on whether the monitoring process is performed by the monitoring unit 28, based on the radio wave from the transmitter 10 received by any one of the detection antennas 21. create. The monitoring unit 28 executes the monitoring process based on the execution availability information.

  With such a configuration, it is possible to determine a period during which radio waves are transmitted from the transmitter 10 based on radio waves received by the detection antenna 21. Thus, for example, in a configuration in which the period is determined based on radio waves received by another antenna provided separately from the detection antenna 21, the quality of radio waves received by the detection antenna 21 is good. However, when the quality of the radio wave received by the other antenna is poor, it is possible to avoid a situation in which the period cannot be determined and a correct monitoring result cannot be obtained.

  Therefore, in the monitoring apparatus according to the first embodiment of the present invention, monitoring errors can be suppressed and the monitoring accuracy can be improved in a configuration in which human action in a predetermined area is monitored using radio waves.

  Since other configurations and operations are the same as those of the monitoring system according to the first embodiment, detailed description thereof will not be repeated here.

  Next, another embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Second Embodiment>
The present embodiment relates to a monitoring system in which a monitoring device creates execution availability information using a different signal compared to the monitoring system according to the first embodiment. The contents other than those described below are the same as those of the monitoring system according to the first embodiment.

[Task]
For example, of the detection antennas 21 included in the receiver 11, radio waves received by the detection antennas 21 used to create execution availability information are received by the detection antennas 21 due to multipath fading. It is assumed that the phase condition that can be canceled in the synthesis of the above is satisfied and the received power of the radio wave in the detection antenna 21 is significantly reduced.

  In such a case, the receiver 11 may not be able to create execution availability information due to a decrease in radio wave reception power. If the receiver 11 cannot create the execution availability information, the receiver 11 cannot calculate the spatial feature amount and cannot monitor the area 5.

  Therefore, the monitoring system according to the present embodiment solves this problem with the following configuration.

[Configuration and basic operation]
FIG. 5 is a diagram illustrating a configuration of a receiver according to the second embodiment of the present invention.

  Referring to FIG. 5, receiver 11 includes detection antennas 21A, 21B, 21C, and 21D, four duplexers (DIVs) 22, a receiver 23, an oscillator 24, a branch circuit 25, and radio waves. The analysis unit 26, the buffer unit 27, the monitoring unit 28, and the antenna selection unit 31 are provided.

  Each duplexer 22 is connected to the corresponding detection antenna 21, branches the output signal of the corresponding detection antenna 21, and outputs the branched signal to the bandpass filter 61 and the antenna selection unit 31.

  The antenna selection unit 31 selects, for example, one detection antenna 21 from each detection antenna 21. The antenna selection unit 31 electrically connects the selected detection antenna 21 and the radio wave analysis unit 26.

  That is, the antenna selection unit 31 outputs a signal received from the selected detection antenna 21 to the radio wave analysis unit 26. Specifically, for example, the antenna selection unit 31 includes a relay, and outputs a signal received from the selected detection antenna 21 to the radio wave analysis unit 26 by switching the contact of the relay.

  More specifically, for example, when the detection antenna 21A is selected from the detection antennas 21A to 21D, the antenna selection unit 31 outputs a signal received from the detection antenna 21A to the radio wave analysis unit 26.

  The radio wave analysis unit 26 creates execution feasibility information based on the signal received from the antenna selection unit 31, that is, the radio wave received by the detection antenna 21 selected by the antenna selection unit 31. Specifically, the radio wave analysis unit 26 creates execution availability information based on the radio wave transmitted from the transmitter 10 among the radio waves received by the detection antenna 21.

  More specifically, for example, the radio wave analysis unit 26 analyzes a signal received from the selected detection antenna 21A via the antenna selection unit 31, and starts the frame similarly to the first embodiment of the present invention. Information is created and output to each A / D converter 64 and buffer unit 27.

  In addition, the radio wave analysis unit 26 analyzes a signal received from the selected detection antenna 21A via the antenna selection unit 31 and creates no-interference information or interference information. Hereinafter, the non-interference information or the interference information is also referred to as interference determination information.

  The radio wave analysis unit 26 outputs the created interference determination information to each A / D converter 64, the buffer unit 27, and the antenna selection unit 31.

  Here, the eigenvector and the spatial feature amount are calculated by the monitoring unit 28 when each A / D converter 64 and the buffer unit 27 receive no-interference information from the radio wave analysis unit 26.

  Therefore, when receiving the interference information from the radio wave analysis unit 26, the antenna selection unit 31 newly selects another detection antenna 21. Specifically, when the antenna selection unit 31 selects the detection antenna 21A and receives interference information from the radio wave analysis unit 26, for example, the antenna selection unit 21B newly selects the detection antenna 21B and detects the detection antenna 21B. The signal received from is output to the radio wave analysis unit 26.

  When the antenna selection unit 31 receives no-interference information from the radio wave analysis unit 26, the antenna selection unit 31 does not newly select another detection antenna 21 and continues to perform radio wave analysis on a signal received from the already selected detection antenna 21. To the unit 26.

  In addition, even when the transmitter 10 transmits a radio wave including a frame, the radio wave analysis unit 26 is used when the received power of the radio wave at the selected detection antenna 21 is low or when the selected detection antenna 21 is selected. When the signal-to-noise ratio of the signal received from is low, SFD and CRC may not be detected based on the signal received from the detection antenna 21.

  In such a case, since the radio wave analysis unit 26 cannot create frame start information and interference determination information, the eigenvector and the spatial feature amount are not calculated in the monitoring unit 28.

  Therefore, the antenna selection unit 31 receives new interference determination information for a predetermined time after receiving the interference determination information from the radio wave analysis unit 26 when it does not receive the interference determination information for a predetermined time after selecting the antenna to be used. If not, select a new antenna.

  For example, the antenna selection unit 31 selects the antennas in the order of the detection antennas 21A, 21B, 21C, and 21D, and then selects the detection antenna 21A again when selecting a new antenna.

  As described above, in the receiver 11 that is the monitoring apparatus according to the second embodiment of the present invention, the antenna selection unit 31 selects any one of the detection antennas 21 from the detection antennas 21. . The radio wave analysis unit 26 creates feasibility information based on the radio wave from the transmitter 10 received by the detection antenna 21 selected by the antenna selection unit 31.

  With such a configuration, for example, due to the poor quality of radio waves received by a detection antenna 21, radio waves are transmitted from the transmitter 10 based on the radio waves received by the detection antenna 21. Even if it is not possible to determine a certain period, the period can be determined using radio waves received by other detection antennas 21.

  Since other configurations and operations are the same as those of the monitoring system according to the first embodiment, detailed description thereof will not be repeated here.

  Next, another embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Third Embodiment>
The present embodiment relates to a monitoring system in which a monitoring device creates execution availability information using a different signal compared to the monitoring system according to the first embodiment. The contents other than those described below are the same as those of the monitoring system according to the first embodiment.

  FIG. 6 is a diagram illustrating a configuration of a receiver according to the third embodiment of the present invention.

  Referring to FIG. 6, receiver 11 includes detection antennas 21A, 21B, 21C, and 21D, four duplexers (DIVs) 22, a receiver 23, an oscillator 24, a branch circuit 25, and radio waves. An analysis unit 26, a buffer unit 27, a monitoring unit 28, and a synthesis unit 32 are provided.

  The combining unit 32 combines the radio waves received by the detection antennas 21. Specifically, each detection antenna 21 converts a radio wave received by itself into an electrical signal and outputs the electrical signal. Each duplexer 22 is connected to the corresponding detection antenna 21, branches the output signal of the corresponding detection antenna 21, and outputs the branched signal to the corresponding bandpass filter 61 and the combining unit 32.

  The synthesizer 32 includes, for example, an analog arithmetic circuit. The synthesizer 32 synthesizes signals received from the duplexers 22 using the analog arithmetic circuit, and outputs the synthesized signal to the radio wave analyzer 26.

  Note that the synthesizer 32 may convert an analog signal received from each detection antenna 21 via the demultiplexer 22 into a digital signal, and perform synthesis processing based on the converted digital signal. For example, if the combining unit 32 determines that the phase of the signal received from each detection antenna 21 is shifted, the combining unit 32 may combine the phase of each signal.

  The radio wave analysis unit 26 creates execution availability information based on the signal received from the synthesis unit 32, that is, the radio wave synthesized by the synthesis unit 32. Specifically, the radio wave analysis unit 26 creates executability information based on the radio wave from the transmitter 10 synthesized by the synthesis unit 32.

  Similarly to the first embodiment of the present invention, when the radio wave analysis unit 26 analyzes the signal received from the synthesis unit 32 and detects the SFD included in the frame, the radio wave analysis unit 26 creates frame start information and generates each A / D Output to the converter 64 and the buffer unit 27. In addition, when the radio wave analysis unit 26 analyzes the signal received from the synthesis unit 32 and detects a CRC included in the frame, the radio wave analysis unit 26 performs error detection of the frame using the CRC, creates interference determination information, and creates each A / The data is output to the D converter 64 and the buffer unit 27.

  The combining unit 32 is not limited to a configuration that combines the radio waves received by all the detection antennas 21, and the radio waves received by two or more detection antennas 21 of the detection antennas 21. What is necessary is just the structure to synthesize | combine.

  For example, the receiver 11 includes an antenna selection unit in the signal transmission path from each duplexer 22 to the synthesis unit 32. In this case, the antenna selection unit receives the output signal of each detection antenna 21 via the corresponding duplexer 22.

  Then, the antenna selection unit selects two or more detection antennas 21 from each detection antenna 21 and outputs a signal received from each selected detection antenna 21 to the combining unit 32. The combining unit 32 combines and outputs the signals received from the antenna selection unit.

  The antenna selection unit as described above may not be provided, and the combining unit 32 may combine the radio waves received by the predetermined plurality of detection antennas 21.

  As described above, in the receiver 11 that is the monitoring apparatus according to the third embodiment of the present invention, the combining unit 32 is received by at least any two of the detection antennas 21. The radio wave from the transmitter 10 is synthesized. The radio wave analysis unit 26 creates executability information based on the radio wave from the transmitter 10 synthesized by the synthesis unit 32.

  With such a configuration, since the quality of the signal used for the determination of the period can be improved, the period can be determined more accurately.

  Since other configurations and operations are the same as those of the monitoring system according to the first embodiment, detailed description thereof will not be repeated here.

  Next, another embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Fourth embodiment>
The present embodiment relates to a monitoring system in which the monitoring device creates feasibility information for each detection antenna as compared to the monitoring system according to the first embodiment. The contents other than those described below are the same as those of the monitoring system according to the first embodiment.

  FIG. 7 is a diagram illustrating a configuration of a receiver according to the fourth embodiment of the present invention.

  Referring to FIG. 7, receiver 11 includes detection antennas 21A, 21B, 21C, and 21D, four duplexers (DIVs) 22, a receiver 23, an oscillator 24, a branch circuit 25, and radio waves. An analysis unit 26, a buffer unit 27, and a monitoring unit 28 are provided. The receiving unit 23 includes four sets of a band pass filter (BPF) 61, a low noise amplifier 62, a quadrature demodulator 63 and an A / D converter (ADC) 64 corresponding to each detection antenna 21.

  Hereinafter, the A / D converters 64 corresponding to the detection antennas 21A, 21B, 21C, and 21D are also referred to as A / D converters 64A, 64B, 64C, and 64D, respectively.

  Each demultiplexer 22 is connected to the corresponding detection antenna 21, branches the output signal of the corresponding detection antenna 21, and outputs it to the corresponding bandpass filter 61 and the radio wave analysis unit 26.

  The radio wave analysis unit 26 creates feasibility information for each of these radio waves based on the radio waves from the transmitter 10 received by at least any two of the detection antennas 21.

  Specifically, for example, the radio wave analysis unit 26 analyzes signals received from each of the detection antennas 21A to 21D and detects SFD included in each signal. For example, the radio wave analysis unit 26 corresponds to the frame start information A and the signal C corresponding to the signal A when the SFD can be detected from the signal A received from the detection antenna 21A and the signal C received from the detection antenna 21C. Frame start information C is created.

  The radio wave analysis unit 26 outputs the created frame start information A to the A / D converter 64A and the buffer unit 27. The radio wave analysis unit 26 outputs the created frame start information C to the A / D converter 64C and the buffer unit 27.

  Then, the radio wave analysis unit 26 detects a CRC from the signal A or the signal C, and detects an error of each frame included in the signal A and the signal C using the detected CRC. The radio wave analysis unit 26 creates no-interference information A when no error is detected for a frame included in the signal A, and creates interference information A when an error is detected for a frame included in the signal A.

  The radio wave analysis unit 26 creates no-interference information C when no error is detected for a frame included in the signal C, and creates interference information C when an error is detected for a frame included in the signal C. To do.

  Here, it is assumed that the radio wave analysis unit 26 has created no-interference information A and no-interference information C. The radio wave analysis unit 26 outputs the created no-interference information A to the A / D converter 64A and the buffer unit 27. The radio wave analysis unit 26 outputs the created no-interference information C to the A / D converter 64C and the buffer unit 27.

  The monitoring unit 28 performs a monitoring process based on the frame start information, the non-interference information, and the interference information that are execution enable / disable information.

  Specifically, when A / D converter 64A and A / D converter 64C receive frame start information A and frame start information C from radio wave analysis unit 26, respectively, I signal and Q received from corresponding quadrature demodulator 63 respectively. The conversion of the signal into the digital signal Ds and the output of the digital signal Ds are started.

  When receiving the frame start information A and the frame start information C from the radio wave analysis unit 26, the buffer unit 27 starts storing the digital signal Ds received from the A / D converter 64A and the A / D converter 64C.

  The A / D converter 64A and the A / D converter 64C stop outputting the digital signal Ds when receiving the no-interference information A and the no-interference information C from the radio wave analysis unit 26, respectively.

  When the buffer unit 27 receives the non-interference information A and the non-interference information C from the radio wave analysis unit 26, the buffer unit 27 stops storing the digital signal Ds received from the A / D converter 64A and the A / D converter 64C, and stores the stored digital signal. The signal Ds is output to the monitoring unit 28. Then, the buffer unit 27 erases the stored digital signal Ds.

  The monitoring unit 28 calculates an eigenvector based on the digital signal Ds received from the buffer unit 27, and calculates a spatial feature amount based on the calculated eigenvector.

  When the radio wave analysis unit 26 creates the interference information A and the interference information C, the radio wave analysis unit 26 sends the interference information A to the A / D converter 64A and the buffer unit 27, and sends the interference information C to the A / D converter 64C and output to buffer unit 27.

  When the A / D converter 64A and the A / D converter 64C receive the interference information A and the interference information C, respectively, the output of the digital signal Ds is stopped.

  When the buffer unit 27 receives the interference information A and the interference information C from the radio wave analysis unit 26, the buffer unit 27 erases the stored digital signal Ds received from the A / D converter 64A and the A / D converter 64C without outputting it. To do.

  The receiver 11 may be configured to include an antenna selection unit in the signal transmission path from each duplexer 22 to the radio wave analysis unit 26. In this case, the antenna selection unit receives the output signal of each detection antenna 21 via the corresponding duplexer 22.

  Then, the antenna selection unit selects two or more detection antennas 21 from each detection antenna 21, and outputs a signal received from each selected detection antenna 21 to the radio wave analysis unit 26. The radio wave analysis unit 26 creates execution availability information for each signal received from the antenna selection unit.

  As described above, in the receiver 11 that is the monitoring device according to the fourth embodiment of the present invention, the radio wave analysis unit 26 receives signals by at least any two of the detection antennas 21. Executability information is created for each radio wave based on the radio wave transmitted from the transmitter 10. The monitoring unit 28 executes a monitoring process for monitoring a human operation in the area 5 based on each execution availability information.

  With such a configuration, it is possible to more accurately determine the period using the execution availability information created for each radio wave.

  Since other configurations and operations are the same as those of the monitoring system according to the first embodiment, detailed description thereof will not be repeated here.

  Next, another embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Fifth embodiment>
The present embodiment relates to a monitoring system in which the monitoring device includes an antenna other than the detection antenna as compared with the monitoring system according to the first embodiment. The contents other than those described below are the same as those of the monitoring system according to the first embodiment.

  FIG. 8 is a diagram illustrating a configuration of a receiver according to the fifth embodiment of the present invention.

  Referring to FIG. 8, the receiver 11 includes a receiver main body 41 and a process execution determination unit 42. The receiver main body 41 includes detection antennas 21A, 21B, 21C, and 21D, four duplexers (DIV) 22, a receiver 23, an oscillator 24, a branch circuit 25, a buffer unit 27, and a monitoring unit. 28. The process execution determination unit 42 includes a radio wave analysis unit 26, an antenna selection unit 31, and an analysis antenna 33.

  The process execution determination unit 42 and the receiver main body 41 may be housed in the same housing or in separate housings. When the process execution determination unit 42 and the receiver main body 41 are housed in separate housings, the process execution determination unit 42 and the receiver main body 41 can be installed apart from each other. The process execution determination unit 42 is preferably installed, for example, in a place where the reception power of the radio wave from the transmitter 10 increases.

  In the process execution determination unit 42, the analysis antenna 33 converts the radio wave received by itself into an electrical signal and outputs the electrical signal to the antenna selection unit 31.

  In the receiver main body 41, each duplexer 22 is connected to the corresponding detection antenna 21, and the output signal of the corresponding detection antenna 21 is branched and output to the corresponding bandpass filter 61 and the antenna selection unit 31. To do.

  The antenna selection unit 31 first selects the analysis antenna 33 as an antenna to be electrically connected to the radio wave analysis unit 26. That is, the antenna selection unit 31 outputs the signal received from the analysis antenna 33 to the radio wave analysis unit 26.

  The radio wave analysis unit 26 creates executability information based on a signal received from the analysis antenna 33 via the antenna selection unit 31, that is, a radio wave received by the analysis antenna 33. Specifically, the radio wave analysis unit 26 creates frame start information and interference determination information that are feasibility information based on the radio wave transmitted from the transmitter 10 among the radio waves received by the analysis antenna 33.

  Specifically, when the radio wave analysis unit 26 analyzes the signal received from the analysis antenna 33 via the antenna selection unit 31 and detects the SFD, it generates frame start information and each A / D converter in the receiver main body 41. 64 and the buffer unit 27.

  Further, when the radio wave analysis unit 26 detects a CRC by analyzing the signal received from the analysis antenna 33 via the antenna selection unit 31, the radio wave analysis unit 26 performs frame error detection using the CRC, and the radio wave from the transmitter 10 is detected. It is determined whether or not other radio wave interference has occurred.

  When the radio wave analysis unit 26 determines that the radio wave from the transmitter 10 has not received interference, the radio wave analysis unit 26 creates non-interference information and outputs it to each A / D converter 64, the buffer unit 27, and the antenna selection unit 31. . On the other hand, when the radio wave analysis unit 26 determines that interference has occurred, the radio wave analysis unit 26 creates interference information and outputs the interference information to each A / D converter 64, the buffer unit 27, and the antenna selection unit 31.

  The radio wave analysis unit 26 is a frame that is execution feasibility information based on the radio wave received by any one of the detection antennas 21 when the reception status of the radio wave by the analysis antenna 33 satisfies a predetermined condition. Start information and interference determination information are created.

  The predetermined condition is, for example, that the radio wave from the transmitter 10 received by the analysis antenna 33 is interfered with other radio waves, and the received power of the radio wave from the transmitter 10 received by the analysis antenna 33. Is lower than a predetermined value, or the signal-to-noise ratio of the signal received from the analysis antenna 33 is lower than the predetermined value.

  The antenna selection unit 31 newly selects one of the detection antennas 21 among the detection antennas 21 when the reception state of the radio wave by the analysis antenna 33 satisfies these conditions.

  More specifically, as described above, when the radio wave analysis unit 26 determines that the radio wave received by the analysis antenna 33 is interfered with other radio waves, the interference selection unit 31 displays the interference information. Send to. Therefore, when receiving the interference information from the radio wave analysis unit 26, the antenna selection unit 31 determines that the radio wave from the transmitter 10 is interfered with other radio waves.

  Also, the radio wave analysis unit 26 is used when the received power of the radio wave from the transmitter 10 is lower than a predetermined value, or when the signal-to-noise ratio of the signal received from the analysis antenna 33 is lower than the predetermined value, for example, the analysis antenna Since CRC cannot be detected based on 33 output signals, interference determination information cannot be created.

  Therefore, when the antenna selection unit 31 does not receive interference determination information from the radio wave analysis unit 26 for a predetermined time after activation of the receiver 11, for example, the reception power of the radio wave from the transmitter 10 is lower than a predetermined value or is analyzed. It is determined that the signal-to-noise ratio of the signal output from the antenna 33 is lower than a predetermined value.

  As in the second embodiment, the antenna selection unit 31 selects one of the detection antennas 21 among the detection antennas 21 and then receives interference information from the radio wave analysis unit 26. Another detection antenna 21 is newly selected.

  Similarly to the second embodiment, when the antenna selection unit 31 does not receive interference determination information for a predetermined time after selecting one of the detection antennas 21 among the detection antennas 21, or Even when new interference determination information is not received for a predetermined time after receiving the interference determination information from the radio wave analysis unit 26, another antenna is newly selected.

  For example, the antenna selection unit 31 selects the antennas in the order of the analysis antenna 33 and the detection antennas 21A, 21B, 21C, and 21D, and then selects the analysis antenna 33 again when selecting a new antenna. select.

  In addition, the radio wave analysis unit 26 displays execution feasibility information based on the radio wave received by any one of the detection antennas 21 when the reception status of the radio wave by the analysis antenna 33 satisfies the predetermined condition. Not only the structure to produce but the structure which produces feasibility information based on the electromagnetic wave received by any two or more detection antennas 21 among each antenna 21 for a detection may be sufficient.

  Specifically, for example, the receiver 11 includes a synthesis unit 32 in a signal transmission path from each duplexer 22 to the antenna selection unit 31. The synthesizer 32 receives and synthesizes the signals output from the respective detection antennas 21 via the corresponding duplexers 22 and outputs the synthesized signals to the antenna selector 31. In this case, the antenna selection unit 31 first outputs the signal received from the analysis antenna 33 to the radio wave analysis unit 26. For example, when receiving interference information from the radio wave analysis unit 26, the antenna selection unit 31 switches the output signal to the signal received from the synthesis unit 32.

  As described above, in the receiver 11 which is the monitoring apparatus according to the fifth embodiment of the present invention, the analysis antenna 33 receives the radio wave transmitted from the transmitter 10. The radio wave analysis unit 26 creates executability information based on the radio wave from the transmitter 10 received by the analysis antenna 33. The radio wave analysis unit 26 also transmits the transmitter 10 received by at least one of the detection antennas 21 when the reception status of the radio wave from the transmitter 10 by the analysis antenna 33 satisfies a predetermined condition. Executability information is created based on radio waves from

  With such a configuration, for example, when the quality of radio waves received by the analysis antenna 33 deteriorates, the antenna used to determine the period during which radio waves are transmitted from the transmitter 10 is detected from the analysis antenna 33. Since it is possible to switch to the antenna 21 for use, it is possible to more reliably determine the period.

  Note that the receiver according to the embodiment of the present invention is configured to perform a binary determination of the presence or absence of human movement or not, but is not limited thereto. It may be configured to output an index indicating the level of possibility of human inactivity or low activity.

  In the receiver according to the embodiment of the present invention, the one-dimensional feature value is used as the spatial feature value. However, the present invention is not limited to this. A configuration using a multidimensional feature value as the spatial feature value may be used. For example, the eigenvector itself can be used as the feature vector, or a delay profile as described in Non-Patent Document 1 can be used.

  Further, the receiver according to the embodiment of the present invention is an array type radio wave sensor, but may be another type of radio wave sensor.

  Since other configurations and operations are the same as those of the monitoring system according to the first embodiment, detailed description thereof will not be repeated here.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The above description includes the following features.

[Appendix 1]
A plurality of detection antennas for receiving radio waves transmitted from transmitters arranged in a predetermined area and including a frame;
A monitoring unit that performs a monitoring process for monitoring human movements in the predetermined area based on the radio waves received by the detection antennas;
A radio wave analysis unit that creates information on whether the monitoring process can be performed by the monitoring unit by analyzing the frame included in the radio wave received by at least one of the detection antennas; With
The monitoring unit is a monitoring device that executes the monitoring process based on the information.

[Appendix 2]
A transmitter arranged in a predetermined area and transmitting a radio wave including a frame;
A monitoring device,
The monitoring device
A plurality of detection antennas for receiving the radio waves transmitted from the transmitter;
A monitoring unit that performs a monitoring process for monitoring human movements in the predetermined area based on the radio waves received by the detection antennas;
A radio wave analysis unit that creates information on whether the monitoring process can be performed by the monitoring unit by analyzing the frame included in the radio wave received by at least one of the detection antennas; Including
The monitoring unit is a monitoring system that executes the monitoring process based on the information.

5 area 10 transmitter 11 receiver 21 detection antenna 22 duplexer 23 reception unit 24 oscillator 25 branch circuit 26 radio wave analysis unit 27 buffer unit 28 monitoring unit 31 antenna selection unit 32 synthesis unit 33 analysis antenna 41 receiver main body 42 Processing execution determination unit 61 Band pass filter 62 Low noise amplifier 63 Quadrature demodulator 64 A / D converter 100 Monitoring system

Claims (7)

A plurality of detection antennas for receiving radio waves transmitted from a transmitter arranged in a predetermined area;
A monitoring unit that performs a monitoring process for monitoring human movements in the predetermined area based on the radio waves received by the detection antennas;
A radio wave analysis unit that creates information related to whether or not the monitoring process can be performed by the monitoring unit based on the radio wave received by at least one of the detection antennas;
The monitoring unit is a monitoring device that executes the monitoring process based on the information. The monitoring device further includes:
An antenna selection unit that selects one or a plurality of the detection antennas from the detection antennas;
The monitoring apparatus according to claim 1, wherein the radio wave analysis unit creates the information based on the radio wave received by the detection antenna selected by the antenna selection unit. The monitoring device further includes:
A synthesizing unit that synthesizes the radio waves received by at least any two of the detection antennas;
The monitoring apparatus according to claim 1, wherein the radio wave analysis unit creates the information based on the radio wave synthesized by the synthesis unit. The radio wave analysis unit creates the information for each radio wave based on the radio wave received by at least any two of the detection antennas.
The monitoring apparatus according to claim 1, wherein the monitoring unit executes the monitoring process based on the information. The monitoring device further includes:
An analysis antenna for receiving the radio wave transmitted from the transmitter;
The radio wave analysis unit creates the information based on the radio wave received by the analysis antenna, and when the reception status of the radio wave by the analysis antenna satisfies a predetermined condition, The monitoring apparatus according to any one of claims 1 to 4, wherein the information is created based on the radio wave received by at least one of them. A transmitter arranged in a predetermined area and transmitting radio waves;
A monitoring device,
The monitoring device
A plurality of detection antennas for receiving the radio waves transmitted from the transmitter;
A monitoring unit that performs a monitoring process for monitoring human movements in the predetermined area based on the radio waves received by the detection antennas;
A radio wave analysis unit that creates information related to whether or not the monitoring process can be performed by the monitoring unit based on the radio wave received by at least one of the detection antennas;
The monitoring unit is a monitoring system that executes the monitoring process based on the information. Receiving radio waves transmitted from transmitters arranged in a predetermined area at a plurality of detection antennas;
Creating information on whether or not to execute a monitoring process for monitoring a human operation in the predetermined area based on the radio wave received by at least one of the detection antennas;
A step of executing the monitoring process based on the radio wave received by each of the detection antennas based on the information.

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