JP2016036072A - Search device and communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a search device and a communication system that can enhance the probability of detecting a person who got lost in a mountain, etc. as compared with prior arts and shorten the detection time.SOLUTION: A searched device 2 supplies power to each part in a first period 321 (for example, 3 ms) every first interval on a standby state to perform reception processing. A search device 1 which enters a search state repetitively transmits a calling signal in a third period 312 longer than the first interval. Upon reception of the calling signal in the first period 321, The searched device 2 transmits a response signal containing its own identification information in a fourth period 322. The search device 1 estimates the distance and direction of the searched device 2 by using the response signal every time the response signal is received. The information on the identification information of the searched device 2 and the distance and direction of the searched device 2 is displayed on the screen.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a search device for searching for another communication device (searched device), and a communication system including the search device and the searched device.

  There is a radio beacon system that informs the rescuer who carries a receiver by transmitting a radio wave (a small transmitter) carried by the climber when a climber is lost due to an avalanche. (Patent Document 1, Patent Document 2, Non-Patent Document 1, etc.).

  In this radio beacon system, the transmission device transmits 457 kHz radio waves as a rescue signal, and the reception device can know the direction and approximate distance of the transmission device from the received radio waves.

  In addition, in order to facilitate the search when it is missing, the supervisor holds the terminal device equipped with the GPS function to the child or the elderly, and the location information of the person to be searched (the terminal device holder) is obtained. An acquisition system is known (see, for example, Patent Document 3).

JP 2003-198389 A JP 2005-229449 A JP-A-8-65413

Report on the study of advanced beacon system for searching for mountain victims (March 2005 Study session on advanced beacon system for searching for mountain victims)

  However, since the radio beacon system uses a medium-frequency band (457 kHz) and the transmission output is limited to a minute power range due to restrictions based on the Radio Law, the radio wave reception distance is about 100 m at the maximum. It cannot be searched if the distance between them is more than that.

  In addition, since the positioning accuracy of the positioning method using the GPS function is usually a radius of several tens of meters, in the system using the terminal device equipped with the GPS function, a range in which a search target person may exist ( The search range can only be specified roughly. In addition, this type of system requires a running cost (communication cost).

  In addition, the radio beacon system device and the terminal device equipped with the GPS function have a large amount of battery consumption, so that it is difficult to use continuously for a long period of time, and there is a limit to downsizing and weight reduction.

  The object of the present invention has been made in view of the above points, and compared to the conventional one, the possibility of finding a search target person is increased, and the search that can shorten the time until discovery is shortened. An apparatus and a communication system are provided.

  The search device of the present invention is a portable search device that directly performs wireless communication with a portable search target device, and transmits the signal to the search target device, and is transmitted from the transmission unit. Receiving means for receiving a signal from the searched device corresponding to the received signal and measuring the received signal strength, and when the received signal strength is equal to or greater than a predetermined threshold, the transmission processing and the receiving processing are continued. And a control unit that controls the receiving unit and performs a warning process for notifying the user of an abnormality when the received signal strength falls below the threshold.

  The communication system of the present invention is a communication system that includes a portable search device and a portable search device that performs wireless communication with the search device, and the search device is connected to the search target device. A first transmission means for transmitting a signal, a first reception means for receiving a signal from the searched device and measuring a received signal strength, and when the received signal strength is equal to or greater than a predetermined threshold, First control for controlling the first transmission unit and the first reception unit to continue reception processing, and performing first warning processing for notifying the user of an abnormality when the received signal strength falls below the threshold value. And second search means for receiving a signal from the search apparatus; and second control means for generating a signal corresponding to the signal received by the second reception means; The second control hand In comprising a second transmission means for transmitting the generated signal, and a configuration.

  According to the present invention, it is possible to increase the possibility of finding a search target person and to shorten the time until discovery.

1 is an external view of a search device according to Embodiment 1 of the present invention. 1 is an external view of a search target device according to Embodiment 1 of the present invention. The block diagram which shows the structure of the search device which concerns on Embodiment 1 of this invention. The block diagram which shows the structure of the to-be-searched apparatus which concerns on Embodiment 1 of this invention. The sequence diagram which shows the mode of communication with the search device and search target device concerning Embodiment 1 of this invention The sequence diagram which shows the mode of communication with the search device which concerns on Embodiment 1 of this invention, and a to-be-searched device. Diagram showing the relationship between distance and received signal strength The figure which shows the directivity formed by the search device which concerns on Embodiment 1 of this invention. The figure which shows the information table stored in the memory part of the search device which concerns on Embodiment 1 of this invention. The figure which shows the display screen of the search device which concerns on Embodiment 1 of this invention. The flowchart which shows the flow of operation | movement of the search device which concerns on Embodiment 1 of this invention. The flowchart which shows the flow of operation | movement of the search device which concerns on Embodiment 1 of this invention. The flowchart which shows the flow of operation | movement of the to-be-searched apparatus which concerns on Embodiment 1 of this invention. The figure which shows an example of the use condition of the search device which concerns on Embodiment 2 of this invention. The sequence diagram which shows the mode of communication with the search device and search target device concerning Embodiment 2 of this invention The flowchart which shows the flow of operation | movement of the search device which concerns on Embodiment 2 of this invention. The flowchart which shows the flow of operation | movement of the search device which concerns on Embodiment 2 of this invention. The figure which shows the display screen of the search device which concerns on Embodiment 2 of this invention. The block diagram which shows the structure of the search device which concerns on Embodiment 3 of this invention. The sequence diagram which shows the mode of communication with the search device and search target device concerning Embodiment 3 of this invention The sequence diagram which shows the mode of communication with the two search apparatuses and search target apparatus which concern on Embodiment 3 of this invention. The flowchart which shows the flow of operation | movement of the search device which concerns on Embodiment 3 of this invention. The flowchart which shows the flow of operation | movement of the to-be-searched apparatus which concerns on Embodiment 3 of this invention. The figure which shows the display screen of the search device which concerns on Embodiment 3 of this invention. The figure which shows the usage example of the search device which concerns on Embodiment 3 of this invention. The figure which shows the usage example of the search device which concerns on the variation of Embodiment 3 of this invention. The sequence diagram which shows the mode of communication with the search device and search target device which concern on the variation of Embodiment 3 of this invention The figure which shows the usage example of the search apparatus and relay apparatus which concern on Embodiment 4 of this invention The sequence diagram which shows the mode of communication of the search apparatus which concerns on Embodiment 4 of this invention, a to-be-searched apparatus, and a relay apparatus. The figure which shows the usage example of the search device and relay apparatus which concern on the variation of Embodiment 4 of this invention

(Embodiment 1)
Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to the drawings. The communication system according to the present embodiment includes a search device 1 (see FIGS. 1 and 3) and one or a plurality of search target devices 2 (see FIGS. 2 and 4). The search device 1 performs wireless communication with each search target device 2. The search device 1 has all the functions of the search target device 2 and can perform wireless communication with other search devices as the search target device.

[Communication mode]
Search device 1 of this embodiment performs one of the following communication modes based on a user's instruction.
(1) Individual search mode (2) Full search mode (3) Group search mode (4) Searched mode

  (1) In the individual search mode, the search device 1 performs wireless communication with the single searched device 2 instructed by the user, and estimates the relative position (distance and direction) of the single searched device 2. Mode. Note that the search device 1 can register the search target device 2 in advance in association with a registration number (for example, 1 to 10).

  (2) The all search mode is a mode in which the search device 1 requests transmission of response signals for all the search target devices 2 and specifies the search target devices 2 that can receive the response signals and communicate with each other.

  (3) In the group search mode, the search device 1 requests transmission of a response signal to all the search target devices 2 registered in advance, and receives the response signal to identify the searchable device 2 that can communicate. Mode.

  (4) The search mode is a mode in which the search device 1 performs wireless communication with another search device as the search target device.

[Structure of search device 1]
First, the structure of the search device 1 will be described with reference to FIG. FIG. 1 is an external view of a search device 1 according to the present embodiment. 1A is a front view, FIG. 1B is a right side view, FIG. 1C is a rear view, and FIG. 1D is a cross-sectional view along AA.

  The search device 1 has a size (for example, width W: 64 mm, height H: 107 mm, thickness T: 13 mm) and weight (for example, 70 g) that a user (general person) can carry.

  The casing 11 of the search device 1 has a substantially rectangular shape and is formed of a non-conductive member. The front surface 11a of the housing 11 has a flat plate shape. A display unit 12 and an operation unit 13 are provided on the front surface 11 a of the housing 11.

  The display unit 12 is provided on the front surface 11a of the housing 11, and has a screen configured by, for example, an LCD (Liquid Crystal Display). The display screen in each communication mode will be described later.

  The operation unit 13 is provided in the vicinity of the bottom surface 11b side (lower end side) on the front surface 11a of the housing 11 and has a plurality of buttons. The operation unit 13 converts the button operation content based on the user's will into an electric signal and transmits it to a CPU (Central Processing Unit) 131 (see FIG. 3).

  The side surfaces 11c and 11d of the housing 11 are thinner on the flat surface 11e side (upper end side) than the bottom surface 11b (lower end side) with the central portion as a boundary. A power switch 14 is provided on the right side surface 11c.

  A substrate 15 is housed inside the housing 11. The antenna 101 is patterned on the plane 11e side (upper end side) from the center of the substrate 15. Various circuits (see FIG. 3) are placed on the substrate 15.

  The antenna 101 includes a first antenna element 111 serving as a radiator at the center, and a second antenna element 112 and a third antenna element 113 each serving as a director or a reflector on both sides thereof.

  The length of the first antenna element 111 is ¼ (λ / 4) of the wavelength λ. For example, when the search device 1 performs wireless communication using 920 MHz, the length (λ / 4) of the first antenna element 111 is about 81.5 mm. The lengths of the second antenna element 112 and the third antenna element 113 are the same and are slightly shorter than the first antenna element 111.

  Each antenna element 111, 112, 113 is formed in a folded pattern so as to be accommodated in a space of length H1 (for example, 40 mm), and is patterned on both surfaces of the substrate 15 and connected in a through hole.

  A recess 16 is provided at the center of the back surface 11 f of the housing 11. When the user holds the search device 1 so that the user can press the button of the operation unit 13 with the first finger (thumb), the user can stabilize the search device 1 by placing the second finger (index finger) in the recess 16. Can have.

[Structure of searched device 2]
Next, the structure of the search target device 2 will be described with reference to FIG. FIG. 2 is an external view (front view) of the search target device 2 according to the present embodiment.

  The search target device 2 has a size (for example, width W: 40 mm, height H: 63 mm, thickness T: 13 mm) and weight (for example, 20 g) that can be carried by a user (general person).

  The casing 21 of the search device 2 has a substantially square shape and is formed of a non-conductive member. An LED (Light Emitting Diode) 22 and a power switch 23 are provided on the front surface 21 a of the housing 21.

  The LED 22 emits light (flashes) at a predetermined timing, for example, when a radio wave is received from the search device 1 in the individual search mode.

  An antenna (see FIG. 4) and a substrate (not shown) are housed inside the housing 21. Various circuits (see FIG. 4) are placed on the substrate.

  On the plane (upper end) of the housing 21, a convex portion 24 having a hole 24a for passing a string or the like is provided. By tying the string passed through the hole 24a to the user's clothes (such as a belt), the searched device 2 does not leave the user even when the user is in an avalanche or the like.

[Circuit Configuration of Searching Device 1 (Block Diagram)]
Next, the circuit configuration of the search device 1 will be described with reference to FIG. FIG. 3 is a block diagram showing a configuration of search device 1 according to the present embodiment. The search device 1 includes a housing 11 (not shown in FIG. 3), a display unit 12, an operation unit 13, a power switch 14 (not shown in FIG. 3), and a substrate 15 (not shown in FIG. 3). ), The antenna 101, the wireless unit 102, the control unit 103, the ringing unit 104, and the battery 105. The wireless unit 102 and the control unit 103 are placed on the substrate 15.

  The wireless unit 102 processes a wireless signal. The wireless unit 102 includes a transmission unit 121, a reception unit 122, a wireless control unit 123, a first clock 124, a first switch 125, a second switch 126, and a third switch 127.

  The transmission unit 121 performs radio transmission processing such as modulation, amplification, and up-conversion on the baseband digital signal output from the CPU 131 and transmits the radio signal from the first antenna element 111. The frequency of the radio wave (call signal or the like) transmitted from the transmission unit 121 is 710 MHz or more and 960 MHz or less.

  The reception unit 122 performs wireless reception processing such as amplification, down-conversion, and demodulation on the wireless signal received by the first antenna element 111 and outputs a baseband digital signal to the CPU 131. In addition, the reception unit 122 measures a received signal strength indicator (RSSI) of a radio wave received by the first antenna element 111 and outputs a measurement value (analog value) to the radio control unit 123.

  The wireless control unit 123 controls each unit in the wireless unit 102 using the clock signal of the first clock 124. In addition, the wireless control unit 123 converts the measurement value of the received signal strength output from the receiving unit 122 into a digital value and outputs the digital value to the CPU 131. Details of the control performed by the wireless control unit 123 for the switches 125, 126, and 127 will be described later.

  The first clock 124 is a high-speed and high-accuracy clock, and generates a reference clock signal having a predetermined frequency (for example, 36 MHz) for use inside the wireless unit 102.

  The first switch 125 connects either the transmission unit 121 or the reception unit 122 and the first antenna element 111 in accordance with an instruction from the radio control unit 123. The second switch 126 connects / disconnects between the substrate 15 and the second antenna element 112 in accordance with an instruction from the wireless control unit 123. The third switch 127 connects / disconnects between the substrate 15 and the third antenna element 113 in accordance with an instruction from the wireless control unit 123.

  The control unit 103 performs baseband signal processing. The control unit 103 includes a CPU 131, a memory unit 132, a second clock 133, a third clock 134, and a logical operation unit 135.

  The CPU 131 is a central processing unit of the control unit 103 and executes various programs using the memory unit 132 as a work memory. In particular, the CPU 131 generates a signal to be transmitted to the search target device 2, and when the radio wave is received from the search target device 2, the CPU 131 displays the acquired predetermined information on the display unit 12, and the ringing unit 104 notifies the notification sound. Is output.

  The memory unit 132 includes a ROM (Read Only Memory) and a RAM (Random Access Memory), and stores various programs executed by the CPU 131 and various data.

  The second clock 133 is a low-speed clock, and generates a reference clock signal having a predetermined frequency (for example, 32 kHz) for use inside the control unit 103 in a standby state or the like. The third clock 134 is a high-speed and high-accuracy clock, and generates a reference clock signal having a predetermined frequency (for example, 40 MHz) for use inside the control unit 103 in a communication state with the search target device 2 or the like.

  The logical operation unit 135 cooperates with the CPU 131 to determine the difference between the transmission timing of the transmission frame and the reference clock of the third clock 134, the difference between the reception timing of the reception frame and the reference clock of the third clock 134, Based on the difference between the transmission timing of the transmission frame and the reference clock of the third clock 234 (see FIG. 4) and the difference between the reception timing of the reception frame and the reference clock of the third clock 234 in the search device 2 The propagation delay time of the transmission line between 2 is calculated.

  The ringing unit 104 outputs a notification sound from the speaker at a predetermined timing, for example, when receiving an instruction from the user.

  The battery 105 is housed in the housing 11, and supplies power to each part of the search device 1 when a user turns on the power via the power switch 14.

[Function of CPU 131]
Next, functions of the CPU 131 of the search device 1 will be described with reference to FIG. The CPU 131 includes a signal generation unit 131a, a signal acquisition unit 131b, a distance estimation unit 131c, and a direction estimation unit 131d as functions according to the present invention.

  The signal generation unit 131a generates a digital signal sequence (transmission frame) including various types of information based on a user instruction (electrical signal input from the operation unit 13) and outputs the digital signal sequence (transmission frame) to the transmission unit 121. In the individual search mode, the signal generation unit 131a includes the identification information of the single searched device 2 and the identification information of the own device instructed by the user in the digital signal. In the all search mode, the signal generation unit 131a includes, in the digital signal, information indicating that all of the search target devices 2 request transmission of response signals. In the group search mode, the signal generation unit 131a includes identification information of all search target devices 2 belonging to the group instructed by the user in the digital signal. In the search mode, when the signal generation unit 131a inputs information requesting transmission of identification information of its own device from the signal acquisition unit 131b, the signal generation unit 131a receives the identification information of its own device and the identification information of the communication partner searching device 1 as a digital signal. Include in In the individual search mode, the signal generation unit 131a includes, in the digital signal (response confirmation signal), information that instructs the search target device 2 to emit light or output a notification sound based on an instruction from the user. Also good.

  In a communication mode other than the search mode, the signal acquisition unit 131b acquires identification information of the search target device 2 from the digital signal sequence (reception frame) of the received response signal and outputs the identification information to the display unit 12. In the searched mode, the signal acquisition unit 131b acquires information from the digital signal sequence (reception frame) of the received call signal, and when the information requests transmission of identification information of the own device, The fact is output to the signal generator 131a. In the all search mode, the signal acquisition unit 131b is based on the user's instruction, and (1) only the one having the highest received signal strength among the acquired identification information of the search target device 2 is registered (2). Any one of (3) that matches the existing identification information may be output to the display unit 12.

  The distance estimation unit 131c estimates the distance to the search target device 2 based on the received signal strength of the radio wave measured by the reception unit 122 or the propagation delay time calculated by the logic operation unit 135 in the individual search mode. The estimated value is output to the display unit 12. Details of the distance estimation in the present embodiment will be described later.

  The direction estimation unit 131d receives the received signal strength when the second switch 126 is ON and the third switch 127 is OFF and the reception when the second switch 126 is OFF and the third switch 127 is ON in the individual search mode. Based on the signal strength, the direction of the search target device 2 is estimated, and the estimated value is output to the display unit 12. Details of direction estimation in the present embodiment will be described later.

[Circuit Configuration of Searched Device 2 (Block Diagram)]
Next, the circuit configuration of the search target device 2 will be described with reference to FIG. FIG. 4 is a block diagram showing a configuration of searched device 2 according to the present embodiment. The searched device 2 includes a housing 21 (not shown in FIG. 4), an LED 22, a power switch 23 (not shown in FIG. 4), a substrate (not shown), an antenna 201, and a wireless unit 202. And a control unit 203, a ringing unit 204, and a battery 205.

  The radio unit 202 processes radio signals. The wireless unit 202 includes a transmission unit 221, a reception unit 222, a wireless control unit 223, a first clock 224, and a first switch 225.

  The transmission unit 221 performs radio transmission processing such as modulation, amplification, and up-conversion on the baseband digital signal output from the CPU 231, and transmits a radio signal from the antenna 201. The frequency of the radio wave (response signal or the like) transmitted from the transmission unit 221 is 710 MHz or more and 960 MHz or less.

  The reception unit 222 performs wireless reception processing such as amplification, down-conversion, and demodulation on the wireless signal received by the antenna 201 and outputs a baseband digital signal to the CPU 231.

  The wireless control unit 223 controls each unit in the wireless unit 202 using the clock signal of the first clock 224.

  The first clock 224 is a high-speed and high-accuracy clock, and generates a reference clock signal having a predetermined frequency (for example, 36 MHz) for use inside the wireless unit 202.

  The first switch 225 connects either the transmission unit 221 or the reception unit 222 and the antenna 201 in accordance with an instruction from the wireless control unit 223.

  The control unit 203 performs baseband signal processing. The control unit 203 includes a CPU 231, a memory unit 232, a second clock 233, and a third clock 234.

  The CPU 231 is a central processing unit of the control unit 203 and executes various programs using the memory unit 232 as a work memory. In particular, the CPU 231 generates a signal to be transmitted to the search device 1, and causes the LED 22 to emit light when the radio wave is received from the search device 1 or when an instruction is received from the search device 1. Is output.

  The memory unit 232 includes a ROM (Read Only Memory) and a RAM (Random Access Memory), and stores various programs executed by the CPU 231 and various data.

  The second clock 233 is a low-speed clock, and generates a reference clock signal having a predetermined frequency (for example, 32 kHz) to be used inside the control unit 203 in a standby state or the like. The third clock 234 is a high-speed and high-accuracy clock, and generates a reference clock signal having a predetermined frequency (for example, 40 MHz) to be used inside the control unit 203 in a communication state with the search device 1 or the like.

  The ringing unit 204 outputs a notification sound from the speaker at a predetermined timing, for example, when a radio wave is received from the search device 1.

  The battery 205 is housed in the housing 21, and supplies power to each part of the search target device 2 when a user turns on the power via the power switch 23.

[Function of CPU 231]
Next, functions of the CPU 231 of the search target device 2 will be described with reference to FIG. The CPU 231 includes a signal generation unit 231a and a signal acquisition unit 231b as functions according to the present invention.

  When the signal generation unit 231a receives information requesting transmission of its own identification information from the signal acquisition unit 231b, the signal generation unit 231a includes a digital signal sequence (transmission frame) including the identification information of the own device and the identification information of the search device 1 of the communication partner. ) And output to the transmission unit 221.

  The signal acquisition unit 231b acquires information from the digital signal sequence (reception frame) of the received call signal, and if the information requests transmission of identification information of the own device, generates a signal to that effect. To the unit 231a. Further, the signal acquisition unit 231 b causes the LED 22 to emit light and output a notification sound from the ringing unit 204 when receiving radio waves from the search device 1 or receiving an instruction from the search device 1.

[Communication sequence in individual search mode]
Next, communication in the individual search mode between search device 1 and search target device 2 according to the present embodiment will be described using the sequence diagram of FIG.

  After the power is turned on, the search device 1 is in a standby state until an instruction from the user (button operation of the operation unit 13) is received. In the standby state, power is not supplied to each unit of the search device 1 in order to reduce power consumption (sleep state). However, power is supplied from the battery 105 to the operation unit 13 and the second clock 133. The second clock 133 always counts by operating a low-speed clock circuit.

  The searched device 2 enters a standby state after being powered on. In the standby state, power is not supplied to each unit of the searchee device 2 in order to reduce power consumption (sleep state). However, power is supplied from the battery 205 to the second clock 233. The second clock 233 always counts by operating a low-speed clock circuit.

  The searchee device 2 supplies power to each unit at each first interval (for example, 3 s) until the count value of the second clock 233 expires (starting state). In the activated state, the searchee device 2 performs reception processing in the first period 321 (for example, 3 ms). At this time, the first clock 224 performs a count operation by operating the clock circuit.

  Then, in the first period 321, the searchee device 2 returns to the sleep state when the information requesting transmission of the identification information of the own device cannot be acquired.

  In the standby state, when the user instructs the identification information of the search target device 2 to be searched, the search device 1 supplies power to each unit and starts searching for the search target device 2 (search state). At this time, the first clock 124 and the third clock 134 perform a counting operation by operating a high-speed clock circuit.

  The search device 1 that has entered the search state first performs reception processing in the second period 311 (for example, 5 ms) in order to confirm that the other search devices 1 are not transmitting radio waves. Then, when the search device 1 does not receive the radio wave from the other search device 1 during the second period 311, the search device 1 in the third period 312 (for example, 3.5 s) longer than the first interval. The call signal including the identification information, the identification information of the search target device 2 to be searched, and the timing information indicating the transmission timing of the response signal to the search target device 2 is repeatedly transmitted.

  The searched device 2 starts communication with the search device 1 (communication state) when receiving the calling signal during any of the first periods 321-3. At this time, the third clock 234 performs a count operation by operating a high-speed clock circuit. Then, in the fourth period 322-1 (for example, 2 ms) designated by the timing information included in the call signal, the searched device 2 detects its own identification information, identification information of the communication partner searching device 1, and distance information ( A response signal including the difference between the transmission timing of the transmission frame and the reference clock of the third clock 234 and the difference between the reception timing of the reception frame and the reference clock of the third clock 234 (in the following description, the call signal is received) Then, the first response signal to be transmitted is referred to as “call response signal”).

  The search device 1 performs reception processing in the fifth period 313 (for example, 100 ms). Then, as soon as the search device 1 receives the call response signal, in the sixth period 314-1 (for example, 2 ms), the response confirmation signal including the identification information of the own device and the identification information of the search target device 2 to be searched. Send. Note that the radio frequency of the response confirmation signal is different from that of the call signal. Therefore, even if the searched device 2 receives the response confirmation signal and the calling signal from the other searching device 1 at the same time, no interference occurs.

  The searched device 2 performs reception processing in a seventh period 323-1 (for example, 3 ms) immediately after the fourth period 322-1. And the to-be-searched apparatus 2 will transmit a response signal again in the 4th period 322-2 after the 2nd space | interval (for example, 100 ms) shorter than a 1st interval will pass, if a response confirmation signal is received.

  Thereafter, the communication system repeats transmission / reception of response signals and transmission / reception of response confirmation signals until a disconnection instruction is received from the user. Each time the search device 1 receives a response signal, the search device 1 estimates the distance and direction of the search target device 2 using the response signal, and obtains identification information of the search target device 2 and information on the distance and direction of the search target device 2. It is displayed on the screen of the display unit 12.

  When there is a disconnection instruction from the user, in the next sixth period 314-7, the search device 1 disconnects its own identification information, identification information of the search target device 2 to be searched, and the search target device 2. A disconnection signal including information for transmitting is transmitted.

  When the searchee device 2 receives the disconnection signal in the corresponding seventh period 323-7, in the next fourth period 322-8, the searchee device 2 receives the identification information of the own device, the identification information of the communication partner search device 1, and the disconnection signal. A disconnection response signal including information indicating that it has been received is transmitted.

  In the next sixth period 314-8, search device 1 transmits a disconnection confirmation signal including its own identification information, identification information of search target device 2 to be searched, and information indicating that a disconnection response signal has been received. Return to the standby state. In addition, when the searchee device 2 receives the disconnection confirmation signal in the next seventh period 323-8, the searchee device 2 returns to the standby state.

[Communication sequence in full search (group search) mode]
Next, the state of communication in the individual search mode between search device 1 and search target device 2 according to the present embodiment will be described using the sequence diagram of FIG. Note that the sequence of the group search mode is the same as that of the full search mode. In addition, since the states of the search device 1 and the search target device 2 in the standby state are the same in all communication modes and have already been described with reference to FIG. 5, description thereof is omitted here.

  In FIG. 6, it is assumed that there are four search target devices 2 (2-1, 2-2, 2-3, 2-4) in a range where radio waves of the search device 1 reach.

  In the all search mode, the search device 1 in the communication state first performs reception processing in the second period 311 (for example, 5 ms) in order to confirm that the other search devices 1 are not transmitting radio waves. Then, when the search device 1 does not receive radio waves from the other search devices 1 during the second period 311, the search device 1 performs all the coverage in the third period 312 (for example, 3.5 s) longer than the first interval. The calling signal including information requesting the search device 2 to transmit identification information is repeatedly transmitted.

  When each search target device 2 receives a call signal during any of the first periods 321-12, 321-22, 321-31, and 321-41, the first interval time from the start of the first period 321 is received. In a fourth period 322 after the elapse, a call response signal including identification information of the own device is transmitted.

  After the expiration of the third period 312, the search device 1 receives the call response signal in a fifth period 313 (for example, 3.5 s) longer than the first interval.

  Thereafter, the communication system repeats transmission / reception of the paging signal and transmission / reception of the paging response signal for a predetermined number N. The search device 1 displays the identification information of the search target device 2 included in the received call response signal on the screen of the display unit 12. Thereafter, the searching device 1 and each searched device 2 return to the standby state.

[Distance estimation]
Next, a method for estimating the distance to the search target device 2 by the search device 1 according to the present embodiment will be described. As a distance estimation method in the field of wireless communication, a first distance estimation method based on received signal strength and a second distance estimation method based on propagation delay time are known.

  FIG. 7 is a diagram illustrating the relationship between distance and received signal strength. In FIG. 7, the horizontal axis represents distance (m), and the vertical axis represents received signal strength (dBm). As shown in FIG. 7, there is a correlation between the distance and the received signal strength, and the longer the distance, the lower the received signal strength. The first distance estimation method is a method of estimating a distance using a correlation between this distance and the received signal strength.

  Here, as shown in FIG. 7, the longer the distance is, the smaller the fluctuation amount of the received signal strength with respect to the unit distance is. Therefore, when the distance to the search target device 2 is short, the search device 1 can estimate the distance with high accuracy by using the first distance estimation method. On the other hand, when the distance to the search target device 2 is long, the radio wave fluctuation becomes gentle. Therefore, when the first distance estimation method is used, the distance cannot be estimated with high accuracy.

  The second distance estimation method is a method for estimating the distance by multiplying the calculated propagation delay time by the speed of the radio wave. The estimation accuracy of the second distance estimation method is substantially constant regardless of the distance. In addition, when the distance to the search target device 2 is long, higher estimation accuracy is not required than when the distance is short.

  In view of the above points, the distance estimation unit 131c of the search device 1 according to the present embodiment receives signals when the measured received signal strength is greater than a predetermined threshold (for example, −50 dBm) (short-distance mode). The distance to the search target device 2 is estimated using the first distance estimation method based on the signal strength, and the search target is searched using the second distance estimation method based on the propagation delay time when it is equal to or less than a predetermined threshold (wide area mode). The distance to the device 2 is estimated.

  In the present embodiment, hysteresis control is used to switch the estimation method, the first threshold for switching from the first distance estimation method to the second distance estimation method, and the second distance estimation method to the first distance estimation method. A second threshold value (> first threshold value) for switching may be set. As a result, it is possible to prevent the estimated distance from greatly changing in a short time due to frequent switching of the estimation method.

  Further, in the present embodiment, switching from the first distance estimation method to the second distance estimation method is performed based on the magnitude relationship between the received signal strength and the third threshold value, and the second distance estimation method to the first distance estimation method. Switching to may be performed based on the magnitude relationship between the propagation delay time and the fourth threshold value.

[Antenna control and direction estimation]
Next, a method for controlling the antenna 101 by the search device 1 and a method for estimating the direction of the search target device 2 according to the present embodiment will be described.

  When receiving the radio wave (response signal), the radio control unit 123 controls the first switch 125 to connect the first antenna element 111 and the receiving unit 122.

  In the individual search mode, the wireless control unit 123 turns on the second switch 126 and connects the substrate 15 and the second antenna element 112 in the first partial period during the reception period of the radio wave (response signal). Then, the third switch 127 is turned OFF to disconnect between the substrate 15 and the third antenna element 113.

  By this control, the connected second antenna element 112 and substrate 15 are longer than the first antenna element 111 (radiator) as a whole, and thus act as a reflector. Moreover, since the 3rd antenna element 113 becomes shorter than the 1st antenna element 111 (radiator), it acts as a waveguide.

  As a result, the first reception directivity 801 in FIG. 8 is formed in the first partial period. At this time, if the user holds the search device 1 substantially horizontally with the plane 11e side (upper end side) in front, the search device 1 can strongly receive radio waves from diagonally forward right.

  In addition, the wireless control unit 123 turns off the second switch 126 and disconnects the substrate 15 from the second antenna element 112 in the second partial period during the reception period of the radio wave (response signal), and the third switch 127 is turned on to connect between the substrate 15 and the third antenna element 113.

  By this control, the connected third antenna element 113 and substrate 15 are longer than the first antenna element 111 (radiator) as a whole, and thus act as a reflector. Moreover, since the 2nd antenna element 112 becomes shorter than the 1st antenna element 111 (radiator), it acts as a waveguide.

  As a result, the second reception directivity 802 in FIG. 8 is formed in the second partial period. At this time, if the user holds the search device 1 substantially horizontally with the plane 11e side (upper end side) in front, the search device 1 can strongly receive radio waves from the diagonally left front.

  When the search target device 2 to be searched exists on the right side of the user, the received signal strength in the first partial period is higher than the received signal strength in the second partial period. Conversely, when the search target device 2 to be searched exists on the left side of the user, the received signal strength in the first partial period is lower than the received signal strength in the second partial period.

  Therefore, according to the present embodiment, the direction of searched device 2 can be estimated from the magnitude and magnitude relationship of the difference in received signal strength between the first partial period and the second partial period.

  Note that the radio control unit 123 turns off the second switch 126 and the third switch 127 during radio wave transmission in the individual search mode, in the full search mode, in the group search mode, and in the searched mode, and the search device 1 is omnidirectional. Sexual transmission / reception may be performed.

  In the present embodiment, as shown in FIG. 9, the memory unit 132 stores an information table indicating an estimated direction based on the magnitude of the difference in received signal strength and its sign (magnitude relationship). The direction estimation unit 131d estimates the direction of the search target device 2 with reference to the information table of FIG. 9 from the received signal strengths measured in the first partial period and the second partial period, and calculates the estimation result. Output to the display unit 12.

  Note that the direction estimation unit 131d may estimate the direction of the search target device 2 using a plurality of measured values of received signal strength. Thereby, the influence of the fluctuation | variation of a propagation path can be absorbed. “Using a plurality of measured values of received signal strength” means, for example, averaging a plurality of received signal strengths for each directivity (simple moving average, weighted moving average, etc.) and using the average value.

[Display screen]
Next, information displayed on the screen of the search device according to the present embodiment will be described with reference to FIG.

  FIG. 10A is a screen at the time of starting the individual search mode when starting the search for the already-searched apparatus 2 that has already been registered. On this screen, an identification number (identification information) 1001 of the search target device 2 to be searched is displayed together with the registration number. When the user instructs search execution in this display state, the search apparatus 1 executes the individual search mode for the search target apparatus 2 whose identification number is displayed on the screen.

  FIG. 10B is a screen at the start of the individual search mode when starting the search for the unregistered search target device 2. This screen displays a portion 1002 in which the input of the identification number (identification information) of the search target device 2 to be searched is completed. When the user instructs the search execution in this display state after completing the input of the identification number, the search device 1 executes the individual search mode (see FIG. 5) for the searched device 2 whose identification number is displayed on the screen. .

  FIG. 10C is a screen at the start of the full search mode. On this screen, a character 1003 of “ALL” is displayed. When the user instructs search execution in this display state, the search device 1 executes the all-in-one search mode (see FIG. 6).

  FIG. 10D is a screen at the start of the group search mode. On this screen, a character 1004 of “registration ALL” is displayed. When the user instructs search execution in this display state, the search device 1 executes the group search mode (see FIG. 6) for all the search target devices 2 registered in advance.

  FIG. 10E is a screen when the individual search mode is executed and a response signal is received from the searchee device 2. This screen shows the identification information 1005-1 of the searched device 2 that has responded, the information 1005-2 about the distance to the searched device 2, the information 1005-3 about the direction of the searched device 2, and the received signal strength. Information 1005-4 and the like are displayed on the screen.

  In the present embodiment, the update of the information 1005-3 regarding the direction of the searchee device 2 is limited to one step at a time. For example, when the previous direction estimation result is 75 ° left and the next direction estimation result is 30 ° right, the screen approaches from the left 75 ° to 30 ° right by one step (15 °). Information indicating the left 60 ° is displayed. Thereafter, when the direction estimation result is continuously 30 ° to the right, information indicating 45 ° left, 30 ° left 15 ° left, 0 °, 15 ° right, and 30 ° right is sequentially displayed on the screen. Is done. Thereby, the influence of the temporary and rapid fluctuation | variation of the estimated direction by radio wave interruption etc. can be absorbed. In addition, the directivity of FIG. 8 varies depending on the user's way of holding the search device 1 and the like, and the direction estimated from the received signal strength and the actual direction of the search target device 2 do not necessarily match. The direction estimation of the form can roughly estimate the direction of the search target device 2 and is sufficiently effective.

  FIG. 10F is a screen when the full search mode or the group search mode is executed and a call response signal is received from the searchee device 2. On this screen, identification information 1006 of all searched devices 2 to be searched is displayed on the screen. At this time, the identification information 1006 of the search target device 2 is displayed from the top in descending order of the received signal strength.

[Description of flow]
Next, the flow of the operation of search device 1 according to the present embodiment will be described using FIG. 11A and FIG. 11B.

  Search device 1 enters a sleep state when power is turned on (ST1101), and waits for an instruction from the user in this state (ST1102).

  When the instruction from the user is the individual search mode (ST1102: individual search mode), the search device 1 transmits a call signal to the search target device 2 (ST1103, ST1104). Then, search device 1 performs reception processing at the timing instructed to searched device 2 in the call signal (ST1105).

  If the call response signal cannot be received in ST1105 (ST1106: NO), search device 1 repeats the steps from ST1104 to ST1106 (ST1107: NO, ST1108). If the call response signal is not received even if the call signal is transmitted M times (ST1107: YES), search device 1 displays a message indicating that there is no response on the screen of display unit 12 (ST1109). Then, the flow proceeds to ST1132.

  If the call response signal can be received in ST1105 (ST1106: YES), search device 1 immediately transmits a response confirmation signal to searched device 2 (ST1110). Search device 1 measures the received signal strength of the response signal (ST1111), estimates the distance to search target device 2 (ST1112), and estimates the direction of search target device 2 (ST1113). Then, search device 1 displays the identification information of search target device 2 and the information related to the distance and direction of search target device 2 on the screen of display unit 12 (ST1114).

  After that, if there is no instruction to end the search from the user (ST1115: NO) and the timer does not end after counting a predetermined time (ST1116: NO), the search device 1 performs the receiving process again at a predetermined interval ( ST1117).

  When the response signal cannot be received in ST1117 (ST1118: NO), search device 1 repeats steps ST1115 to ST1117. On the other hand, if a response signal can be received in ST1117 (ST1118: YES), the flow returns to ST1110, and search device 1 repeats the steps from ST1110 to ST1117 (communication state).

  In this communication state, when the user gives an instruction to end the search (ST1115: YES), or when the timer ends by measuring a predetermined time (ST1116: YES), the search device 1 transmits a disconnection signal, A disconnection signal reception and disconnection confirmation signal transmission disconnection process is performed (ST1119). Then, the flow proceeds to ST1132.

  In ST1102, when the instruction from the user is the full search mode or the group search mode (ST1102: full search mode, group search mode), search device 1 is registered for all search target devices 2 or in advance. Call signals are transmitted to all the searched devices 2 all at once (ST1121, ST1122), and reception processing is performed over a predetermined period (ST1123). Searching apparatus 1 repeats steps ST1122 and ST1123 N times (ST1124, ST1125).

  When no response signal has been received in N times of ST1123 (ST1126: NO), search device 1 displays a message indicating that there is no response on screen of display unit 12 (ST1127). ). Then, the flow proceeds to ST1132.

  If even one response signal can be received in N times of ST1123 (ST1126: YES), searching device 1 displays the identification information of searched device 2 on the screen of display unit 12 (ST1128).

  After that, if there is no instruction to shift to the individual search mode or an instruction to end the search from the user (ST1129: NO, ST1130: NO), and the timer does not end after measuring a predetermined time (ST1131: NO), search device 1 Repeats step ST1128.

  If there is an instruction to shift to the individual search mode after ST1128 (ST1129: YES), the flow proceeds to ST1103. If the search is instructed by the user (ST1130: YES), or if the timer expires after measuring a predetermined time (ST1131: YES), the flow proceeds to ST1132.

  If the power is not turned off in ST1132, (ST1132: NO), the flow returns to ST1101. On the other hand, if the power is turned off in ST1132 (ST1132: YES), the flow ends.

  In ST1102, when the instruction from the user is the search mode (ST1102: search mode), the flow proceeds to ST1201 in FIG. 12, and search device 1 operates as the search target device.

  Next, the flow of operation of the searchee device 2 according to the present embodiment will be described using FIG.

  The searchee device 2 enters a sleep state when the power is turned on (ST1201), and performs reception processing periodically (at the first interval) (ST1202).

  If the call signal cannot be received in ST1202 (ST1203: NO), searched device 2 returns to the sleep state of ST1201.

  When a call signal can be received in ST1202 (ST1203: YES), searched device 2 transmits a response signal to search device 1 at a designated timing (ST1204), and immediately performs reception processing (ST1205). .

  If a response confirmation signal can be received in ST1205 (ST1206: YES), searched device 2 transmits a response signal again to searching device 1 after a predetermined time (second interval) has passed (ST1204). Thereafter, when a response confirmation signal can be received (ST1206: YES), steps ST1204 and ST1205 are repeated.

  If no response confirmation signal is received in ST1205 (ST1206: NO) and a disconnection signal is received (ST1207: YES), searched device 2 performs a disconnection process of disconnection response signal transmission and disconnection confirmation signal reception (ST1208). . Then, the flow proceeds to ST1209.

  If neither a response confirmation signal nor a disconnection signal is received in ST1205 (ST1206: NO, ST1207: NO), the flow proceeds to ST1209.

If the power is not turned off in ST1209 (ST1209: NO), the flow returns to ST1201. On the other hand, if the power is turned off in ST1209 (ST1209: YES), the flow ends.
[effect]
As described above, according to the present embodiment, the searched device 2 does not always need to transmit a periodic signal such as a beacon, and only receives a response signal when receiving a call signal from the searching device 1. Since transmission is sufficient, power consumption is reduced as compared to conventional devices. Therefore, the searched device 2 can continuously operate for a long period (for example, three months or more), and the battery runs out until the user descends even if the user turns on the power in advance such as when entering the mountain. There is no worry. Furthermore, if the search target device 2 is turned on in advance, the search target device 2 can perform wireless communication with the search device 1 without further user operation, so that the user is in an avalanche or the like. Even if the user loses his or her mind, the search device 1 can specify the position of the search target device 2.

  In addition, since the search device 1 and the search target device 2 perform wireless communication using a frequency of 710 MHz or more and 960 MHz or less, the searchable device 2 has a long radio wave receivable distance from the search device 1. A wide range (for example, 100 m to 5 km) can be searched. If a higher frequency is used like 2.4 GHz of WLAN, the antenna becomes shorter and the receivable distance becomes shorter. Further, when a higher frequency is used, the straightness of radio waves becomes stronger and the wraparound is reduced, so that the possibility of finding a search target person such as a victim in an environment where there is an obstacle is reduced. On the other hand, if a lower frequency is used, the antenna becomes longer and the device becomes larger.

  Further, by using the distance estimation method of the present embodiment, the search device 1 can accurately estimate the relative distance to the search target device 2 when the search target device 2 exists at a short distance. When the searched device 2 does not exist at a short distance, the relative distance to the searched device 2 can be estimated with a predetermined accuracy.

  Further, by using the antenna structure and switching control of the present embodiment, the circuit scale of the antenna portion can be reduced and the entire apparatus can be reduced in size and weight as compared with the case of using an array antenna. In the first antenna element 111 (radiator) that receives radio waves, switching for switching directivity is not performed, so that switching loss is minimized. Further, since the switching timing of the second switch 126 and the third switch 127 is the same, there is only one control system for switching the switch.

  Further, by providing the recess 16 at the center of the back surface 11f of the casing 11 of the search device 1 of the present embodiment, the user can press the button of the operation unit 13 with the first finger (thumb). When the search device 1 is held in the hand, the search device 1 can be stably held by placing the second finger (index finger) in the recess 16. Also, this way of holding can prevent the influence of the antenna directivity and stabilize the direction estimation accuracy because hands and fingers do not come around the antenna elements 111, 112, and 113.

  In addition, when the searched device 2 of the present embodiment receives radio waves from the searching device 1 or receives an instruction from the searching device 1, the LED 22 is caused to emit light and the sounding unit 204 outputs a notification sound. The user of the search device 1 can search the search target device 2 by his / her own visual or auditory sense.

  And according to this Embodiment, by said effect, possibility that a search subject person, such as a mountain victim, will be discovered more, and it can be anticipated that time until it is discovered is shortened more.

  In the above embodiment, a case has been described in which the search target device 2 always transmits a call response signal when receiving the call signal from the search device 1 in the full search mode or the group search mode. The search target device 2 stores the identification information of the predetermined search device 1 in advance, and when the call signal from the search device 1 is received, the search target device 2 stores the call information in the stored identification information of the search device 1. The paging response signal may be transmitted only when there is a match with the identification information of the search device 1 included in the signal.

  Thereby, the search device 1 can display only the identification information of the searched device 2 in which the identification information of the own device is registered. In addition, since the number of times of transmitting the call response signal is relatively reduced, the searched device 2 can suppress power consumption.

  Moreover, although the said embodiment demonstrated the case where the information regarding the estimated distance and direction of the to-be-searched apparatus 2 was displayed on screens, such as LCD of the search apparatus 1, this invention is not limited to this, The search apparatus 1 Other display methods may be used such as providing a plurality of LEDs on the front surface of the housing 11 and changing the position of the LED to emit light according to the distance and direction of the search target device 2.

  In the above embodiment, the case where the identification information of the search target device 2 is displayed on the screen of the search device 1 has been described. However, the present invention is not limited to this. For example, the search device 1 includes a speaker, The identification information of the search target device 2 may be output by voice from a speaker.

  Moreover, although the said embodiment demonstrated the case where the recessed part 16 was provided in the center part of the back surface 11f of the housing | casing 11 of the search device 1 in order to prevent affecting antenna directivity, this invention is not limited to this. However, it may be possible to prevent hands and fingers from coming around the antenna elements 111, 112, and 113 by other constituent values, such as providing a convex portion on the flat surface 11e side (upper end side) slightly from the center of the back surface 11f. good.

(Embodiment 2)
In snowy mountains, etc., the team usually consists of multiple people who search for the victims. In this case, it is important to quickly inform other members of information such as that one person in the team has found a victim and share the information within the team for relief activities.

  In the second embodiment, an example of using a search device when searching by a team will be described. In the present embodiment, the configuration of the search device and the searched device is the same as that described in the first embodiment, and a description thereof will be omitted.

[Description of usage status]
FIG. 13 is a diagram illustrating an example of a usage state of the search device according to the present embodiment. In FIG. 13, searchers # 1A, # 1B, # 1C, and # 1D of four teams use search devices 1A, 1B, 1C, and 1D, respectively, and search target devices equipped with search target devices 2 are used. The example which searches for person # 2 is shown. Then, it is assumed that searched device 2 transmits a response signal to searching device 1A possessed by searcher # 1A, and searching device 1A is communicating with searched device 2.

  In this case, in this embodiment, the other searchers # 1B, # 1C, and # 1D receive the response signal from the search target device 2 of the search target # 2 by the search device 1A of the searcher # 1A. Can be known by the search devices 1B, 1C, and 1D that the user has. In other words, in this embodiment, each member can easily confirm that one person in the team can communicate with the search target device of the search target person without using other communication means. This will be described below.

[Communication sequence]
FIG. 14 is a sequence diagram illustrating a state of communication between the search device and the search target device according to the present embodiment. In FIG. 14, communication has already been performed between the search device 1A possessed by the searcher # 1A and the search target device 2 possessed by the searchee # 2. In this state, it is assumed that search device 1B possessed by searcher # 1B has started searching.

  In the third period 312B, the search device 1B responds to the identification information of the own device, the identification information of the search target device to be searched, and the search target device 2 as described in the first embodiment (FIG. 5). The call signal including timing information indicating the signal transmission timing is repeatedly transmitted.

  Thereafter, the search device 1B receives the response signal transmitted from the search target device 2 to the search device 1A in the fifth period 313B. Since this response signal includes the identification information of the searched device 2, the identification information of the searching device 1A in communication, etc., the searching device 1B indicates that the searched device 2 is communicating with the searching device 1A. Can be recognized. When the search device 1B receives a response signal including identification information of another search device, the search device 1B performs a display process of predetermined information described later.

  In the above description, a case has been described in which search device 1B shifts to a display operation based on information included in a response signal transmitted from search target device 2, but in this embodiment, search device 1B The display operation may be shifted based on information included in the response confirmation signal transmitted from the search device 1A.

  Whether the search device 1B receives the response signal from the search target device 2 or the response confirmation signal from the search device 1A in the fifth period 313B is determined by the search device 1B and the search target device 2 or the search device 1A. It depends on the positional relationship. Depending on the terrain, generally, if the distance between the search device 1B and the search device 1A is shorter than the distance between the search device 1B and the search target device 2, the search device 1B searches for the fifth period 313B. The possibility of receiving a response signal from the device 1A increases.

[Description of flow]
FIG. 15 is a flowchart showing a flow of operations of the search device according to the present embodiment. In FIG. 15, steps common to those in FIG. 11 are denoted by the same reference numerals and description thereof is omitted. In FIG. 15, compared with FIG. 11, ST1301 to ST1304 are added.

  If the call response signal can be received in ST1105 (ST1106: YES), search device 1 determines the call response signal or identification information included in the call signal (ST1301).

  If the identification information is addressed to the own device (ST1301: YES), the flow proceeds to ST1110, and search device 1 immediately transmits a response confirmation signal to searched device 2 (ST1110).

  On the other hand, when the identification information is addressed to another search device (ST1301: NO), search device 1 causes display unit 12 to display the identification information of the other search device (ST1302).

  Thereafter, when there is no instruction to end the search from the user (ST1303: NO), and the timer does not end with a predetermined time (ST1304: NO), search device 1 repeats the step of ST1302. Further, when the user gives an instruction to end the search (ST1303: YES), or when the timer ends by measuring a predetermined time (ST1304: YES), the flow proceeds to ST1132.

[Display screen]
FIG. 16 shows the screen of search device 1 in ST1302. This screen is displayed when the searchee device 2 is communicating with another search device 1 after the screen shown in FIG. On this screen, the identification information 1401 of the search target device 2 and the identification information 1402 of another search device 1 in communication with the search target device 2006 are displayed on the screen.

[effect]
As described above, according to the present embodiment, the search device can display the identification information of the search device in communication with the search target device. Thus, each member can easily and quickly confirm that one member of the team has been able to communicate with the searchee device of the searchee without using other communication means. Therefore, all the teams can cooperate with each other and perform a rescue operation for a search target person such as a victim quickly and efficiently.

  Further, since the search device can obtain the identification information of the other search device even from the response confirmation signal from the other search device communicating with the search target device, each member receives a signal from the search target device. There is a possibility that one person in the team can confirm that the search target person's search target device can communicate with the search target device even in an area that does not reach. Therefore, according to the present embodiment, the area to be searched can be enlarged.

  Moreover, although the said embodiment demonstrated the case where the identification information of the to-be-searched apparatus 2 and the identification information of another search apparatus were displayed on the screen of the search apparatus 1, this invention is not limited to this, For example, search The device 1 may include a speaker, and the identification information of the searched device 2 and the identification information of another searching device may be output from the speaker.

(Embodiment 3)
In the third embodiment, an example of use of a search device that senses that the owner of the search target device (such as an elderly person) has come out of a predetermined range (hereinafter referred to as “watch range”) that can be reached by the observer. Will be described.

[Communication mode]
The communication mode in the present embodiment is referred to as “watch mode”. In the watching mode, the search device 1 performs wireless communication with the single watched device 2 to be watched by the user (monitor) using an individual channel (wireless frequency), and the watched device to be watched is monitored. In this mode, it is estimated whether or not the device 2 is within the watching range. In search device 1 and search target device 2 according to the present embodiment, a watch mode function is added to the contents described in the first embodiment. Note that the radio frequency of the individual channel used in the watching mode is different from the radio frequency of the common channel used during the search.

[Additional function of search device]
FIG. 17 is a block diagram showing a configuration of the search device according to the present embodiment. In the search device 1 shown in FIG. 17, portions common to those shown in FIG. 3 are denoted by the same reference numerals as those in FIG. 3 and description thereof is omitted. The search apparatus 1 shown in FIG. 17 employs a configuration in which a warning processing unit 131e is added to FIG. Further, functions are added to the signal generation unit 131a and the signal acquisition unit 131b in FIG.

  When starting the watching mode, the signal generation unit 131a identifies its own identification information, identification information of the search target device 2 to be monitored, and timing information that instructs the search target device 2 to transmit a response signal. And a digital signal sequence (transmission frame) of the calling signal in the watching mode including the individual channel information indicating the radio frequency of the individual channel used in the watching mode. In addition, during the monitoring mode communication, the signal generation unit 131a generates a digital signal sequence (transmission frame) of the monitoring mode response confirmation signal including the identification information of the own device and the identification information of the search target device 2 to be monitored. To do.

  The signal acquisition unit 131b acquires identification information of the search target device 2 from the digital signal sequence (reception frame) of the received response signal in the monitoring mode during the communication in the monitoring mode, and outputs the identification information to the display unit 12.

  The warning processing unit 131e compares the received signal strength of the radio wave measured by the receiving unit 122 with a predetermined threshold during the communication in the watching mode. When the received signal strength is equal to or higher than the threshold, the warning processing unit 131e estimates that the search target device 2 to be watched is within the watch range and indicates that the watch mode communication is continued. Information is output to the display unit 12. On the other hand, when the received signal strength is lower than the threshold, the warning processing unit 131e estimates that the device to be watched 2 to be watched is out of the watch range, and outputs information indicating that to the display unit 12. Perform warning processing. Note that the warning processing unit 131e, for example, averages the received signal strength when the received signal strength is lower than the threshold value n times (n is a natural number of 2 or more), or (simple moving average, weighted). When the average value is lower than a threshold value, it may be estimated that the search target device 2 to be watched is out of the watch range. This can prevent erroneous detection due to fading fluctuations.

  The warning process of the search device 1 is a process for notifying (calling attention) to the user (monitor) that the search target device 2 to be watched is out of the watch range (abnormality). For example, a warning sound is output from the speaker of the ringing unit 104, the search device 1 is vibrated, and the display of the display unit 12 is blinked.

  When the warning processing unit 131e executes warning processing, the signal generation unit 131a includes information (hereinafter referred to as "warning") in the response confirmation signal in the watching mode that instructs the search target device 2 to execute warning processing. Instruction information ”).

  In the present embodiment, it is assumed that the user can set a threshold value. For example, the user may be able to select a threshold value from five levels prepared in advance. The distance between the search device 1 and the search target device 2 from which a predetermined received signal intensity is obtained varies depending on the use environment (wooden, reinforced concrete, etc.) and mounting conditions (human body proximity, mounting height, etc.). The user can appropriately set the watching range by adjusting the threshold in consideration of the use conditions.

  In the above description, the case where the warning processing unit 131e compares the received signal strength of the radio wave measured by the receiving unit 122 with a predetermined threshold value has been described. In an environment with a small amount of information, the warning processing unit 131e may compare the distance estimated by the distance estimation unit 131c with a predetermined threshold.

[Additional functions of searched device]
In the present embodiment, the structure of the searched device is the same as that in FIG. However, in the present embodiment, functions are added to the signal generation unit 231a and the signal acquisition unit 231b.

  When the signal generation unit 231a receives information indicating that the watch mode call signal or the response confirmation signal has been received from the signal acquisition unit 231b, the signal generation unit 231a includes the identification information of the own device and the identification information of the search device 1 of the communication partner. A digital signal sequence (transmission frame) of the mode response signal is generated.

  When the signal acquisition unit 231b receives the watch mode call signal or the response confirmation signal including the identification information of the own device, the signal acquisition unit 231b outputs the fact to the signal generation unit 231a. Further, the signal acquisition unit 231b executes warning processing when information for instructing execution of warning processing is included in the response confirmation signal in the watching mode.

  The warning process of the searchee device 2 is a process for notifying the user of the searchee device 2 that he / she has gone out of the watch range. For example, the recorded sound is output from the speaker of the ringing unit 204. This is a process of outputting, vibrating the searchee device 2, blinking the LED 22, and the like.

[Communication sequence]
FIG. 18 is a sequence diagram showing a state of communication between search device 1 and search target device 2 according to the present embodiment.

  In the watching mode, after the power is turned on, the search device 1 and the search target device 2 are in a standby state as in the individual search mode.

  In the standby state, the searchee device 2 performs reception processing in the first period 321 (for example, 3 ms) at every first interval (for example, 3 s) (activated state). Then, in the first period 321, the searchee device 2 returns to the sleep state when the information requesting transmission of the identification information of the own device cannot be acquired.

  In the standby state, when the search device 1 is instructed by the user to execute the watch mode and the identification information of the search target device 2 to be watched, the search device 1 enters the search state and performs reception processing in the second period 311 (for example, 5 ms). If the radio wave from the other search device 1 is not received during the second period 311, in the third period 312 (for example, 3.5 s) longer than the first interval, the identification information of the own device, Watching including identification information of the device to be watched 2 to be watched over, timing information for instructing the device to be watched 2 to transmit a response signal, and individual channel information indicating the radio frequency of the individual channel used in the watch mode The mode call signal is transmitted repeatedly.

  When the searchee device 2 receives the watch mode call signal during any of the first periods 321-3, the radio frequency of the dedicated channel in the fourth period 322-1 (for example, 2 ms) specified by the timing information. Then, a response signal in the watching mode including the identification information of the own device and the identification information of the search device 1 of the communication partner is transmitted. Note that the searched device 2 uses the radio frequency of the common channel in the first period 321 (for example, 3 ms) every first interval (for example, 3 s) even after starting the monitoring mode communication with the searching device 1. Perform reception processing.

  The search device 1 performs reception processing in the watch mode in the fifth period 313 (for example, 100 ms). Then, as soon as the search device 1 receives the response signal in the watch mode, in the sixth period 314-1 (for example, 2 ms), the search device 1 uses its own channel identification information and the watch target search device at the radio frequency of the individual channel. The response confirmation signal in the watching mode including the identification information 2 is transmitted.

  The searched device 2 performs reception processing in the watching mode in the seventh period 323-1 (for example, 3 ms) immediately after the fourth period 322-1. And the to-be-searched apparatus 2 will transmit a response signal again in the 4th period 322-2 after 1st space | interval (for example, 3 s) will be received, if the response confirmation signal of watch mode is received. The searchee device 2 may perform the reception process in the first period 321 continuously after the reception process in the watching mode in the seventh period 323. As a result, the number of times the receiving circuit is activated can be reduced, so that power saving can be achieved.

  Thereafter, the communication system repeats transmission / reception of the response signal in the monitoring mode and transmission / reception of the response confirmation signal in the monitoring mode until a disconnection instruction is received from the user. Note that by increasing the transmission interval of the response signal in the watching mode (for example, 3 s), the power consumption of the search target device 2 can be suppressed.

  The search device 1 measures the received signal strength of radio waves each time a response signal in the watching mode is received. Then, when the received signal strength of the radio wave is equal to or higher than a predetermined threshold, the search device 1 indicates identification information of the search target device 2 to be watched over and that the search target device 2 is within the watch range. Information is displayed on the screen of the display unit 12. On the other hand, when the received signal strength of the radio wave is lower than a predetermined threshold (outflow determination), the search device 1 identifies the search target device 2 to be watched and the search target device 2 goes out of the watch range. Information indicating this is displayed on the screen of the display unit 12 and a warning process is executed.

  After that, if there is an instruction for searching for the search target device 2 to be watched by the user during the communication in the watch mode, the search device 1 transmits a call signal for the individual search mode and communicates with the search target device 2. Then, the communication in the individual search mode (communication sequence shown in FIG. 5) is executed. At this time, the searchee device 2 stops the transmission process of the response signal in the watching mode and the reception process of the response confirmation signal in the watching mode.

  Although not shown in FIG. 18, if there is a disconnection instruction from the user during the communication in the watching mode, the disconnection signal and the disconnection are performed between the search device 1 and the search target device 2 as in the individual search mode. The response signal and the disconnection confirmation signal are transmitted / received, and the searching device 1 and the searched device 2 return to the standby state.

  Further, in the present embodiment, while the search device 1 is communicating with the search target device 2 in the watch mode, another search device 1 sends a call signal for the individual search mode to the search target device 2. Can be transmitted and communication in the individual search mode can be executed with the search target device 2 (a combination of the watching mode and the individual search mode).

  In this case, as shown in FIG. 19, the searchee device 2 receives the call signal for the individual search mode transmitted from the other search device 1X to the searchee device 2 during communication in the watch mode with the search device 1. Upon reception, the monitoring mode response signal transmission processing, the monitoring mode response confirmation signal reception processing, and the reception processing are stopped at the radio frequency of the common channel. Then, the searchee device 2 transmits an individual search mode response signal to the search device 1X.

  The search device 1 receives the response signal in the individual search mode addressed to the search device 1X. Since the response signal includes the identification information of the searched device 2 and the identification information of the searching device 1X, the searching device 1 recognizes that the searched device 2 is communicating with the searching device 1X. be able to. In this case, the search device 1 stops the transmission of the response confirmation signal, and repeats the reception process of the response signal in the individual search mode in the first interval (for example, 3 s) and the fifth period 313 (for example, 100 ms).

  Note that when the individual search mode communication between the search device 1X and the search target device 2 is finished and the search device 1 cannot receive a signal from the search target device 2, the search device 1 enters the search state again and performs the monitoring mode communication. Start. Thereby, the search device 1 can continue the communication in the watching mode with the search target device 2.

[Description of flow]
Next, the flow of operation of search device 1 according to the present embodiment will be described using FIG.

  Search device 1 enters a sleep state when power is turned on (ST2001), and waits for an instruction from the user in this state (ST2002).

  When the instruction from the user is the watch mode (ST2002: watch mode), the search device 1 transmits a call signal for the watch mode to the watched device 2 to be watched (ST2003, ST2004). Then, search device 1 performs reception processing at the timing instructed to search target device 2 in the watch mode call signal and the radio frequency of the dedicated channel (ST2005).

  If the call response signal in the watch mode cannot be received in ST2005 (ST2006: NO), search device 1 repeats the steps from ST2004 to ST2006 (ST2007: NO, ST2008). If the paging response signal cannot be received even if the paging signal in the watching mode is transmitted M times (ST2007: YES), the search device 1 displays a message indicating that there is no response on the screen of the display unit 12 ( ST2009). Then, the flow proceeds to ST2018.

  If a call response signal in the watch mode can be received in ST2005 (ST2006: YES), search device 1 immediately transmits a response confirmation signal to searched device 2 (ST2010). In addition, the search device 1 measures the received signal strength of the response signal and compares it with a predetermined threshold (ST2011, ST2012).

  If the received signal strength of the radio wave is equal to or greater than a predetermined threshold (ST2012: YES), the search device 1 identifies the search target device 2 to be watched over and the search target device 2 is within the watch range. Information indicating that the user is present is displayed on the screen of display unit 12 (ST2013).

  After that, if there is no instruction to end the search from the user (ST2014: NO), search device 1 performs reception processing again at a predetermined interval (ST2015).

  If the response signal can be received in ST2015 (ST2016: YES), the flow returns to ST2010, and search device 1 repeats the steps ST2010 to ST2016 (communication state).

  In this communication state, when the user gives an instruction to end the search (ST2014: YES), search device 1 performs a disconnection process of disconnection signal transmission, disconnection response signal reception, and disconnection confirmation signal transmission (ST2017). Then, the flow proceeds to ST2018.

  On the other hand, when the received signal strength of the radio wave is lower than a predetermined threshold (ST2012: NO), or when the response signal cannot be continuously received N times in ST2015 (ST2016: NO, ST2019: YES), search The device 1 displays the identification information of the search target device 2 to be watched over and information indicating that the search target device 2 has gone out of the watch range on the screen of the display unit 12 and executes a warning process. (ST2020). In addition, when the frequency | count that a response signal cannot be received is less than N (ST2019: NO), the search device 1 repeats the reception process of ST2015.

  Further, the search device 1 displays information that prompts the user to switch to the individual search mode, and when the user instructs to switch the communication mode (ST2021: YES), the flow is shown in FIGS. 11A and 15A. Proceeding to ST1102, the search apparatus 1 performs processing according to FIGS. 11A and 11B or FIGS. 15A and 15B.

  If a communication mode other than the watch mode is selected in ST2002 (ST2002: other communication mode), or if the user is instructed to execute another communication mode in the middle of the flow of FIG. Goes to ST1102 shown in FIGS. 11A and 15A, and the search apparatus 1 performs processing in accordance with FIGS. 11A and B or FIGS. 15A and 15B.

  Next, the operation flow of the searchee device 2 according to the present embodiment will be described with reference to FIG.

  Searched apparatus 2 enters a sleep state when power is turned on (ST2101), and performs reception processing at the radio frequency of the common channel periodically (at the first interval) (ST2102).

  If the call signal cannot be received in ST2102 (ST2103: NO), searched device 2 returns to the sleep state of ST2101.

  If the watch mode call signal can be received in ST 2102 (ST 2103: YES, ST 2104: YES), the searched device 2 responds to the search device 1 in the watch mode at the designated timing and the radio frequency of the dedicated channel. A signal is transmitted (ST2105), and reception processing is performed immediately on the radio frequency of the designated dedicated channel (ST2106).

  If the response confirmation signal in the watching mode can be received in ST2106 (ST2107: YES), searched device 2 performs reception processing at the radio frequency of the common channel after elapse of a predetermined time (first interval) from the reception processing in ST2102. (ST2108).

  When the call signal cannot be received in ST2108 (ST2109: NO), the searchee device 2 again responds to the search device 1 in the watch mode after a predetermined time (first interval) has elapsed from the reception processing of ST2106. A signal is transmitted (return to ST2105).

  If the response confirmation signal is not received in ST2106 (ST2107: NO) and the disconnection signal is received (ST2110: YES), searched device 2 performs disconnection processing of disconnection response signal transmission and disconnection confirmation signal reception (ST2111). . Then, the flow returns to ST2101.

  On the other hand, when neither a response confirmation signal nor a disconnection signal has been received (ST2107: NO, ST2110: NO), up to N consecutive times (ST2112: NO), the searchee device 2 monitors the search device 1 in a watch mode. Is transmitted (return to ST2105). If neither the response confirmation signal nor the disconnection signal is received continuously N times (ST2107: NO, ST2110: NO, ST2112: YES), the flow returns to ST2101.

  If a call signal other than the watch mode is received in ST2102 or ST2108 (ST2103: YES, ST2104: NO, or ST2109 :: NO), the flow proceeds to ST1204 shown in FIG. 2 performs processing according to FIG.

[Display screen]
FIG. 22A shows a screen of search device 1 in ST2013. In this screen, identification information 2201-1 of the search target device 2 to be watched over, information indicating that the search target device 2 is within the watch range (letters “watching”) 2201-2, and reception Information 2201-3 indicating the electric field strength is displayed. Note that FIG. 22A shows an example of displaying a line graph with time on the horizontal axis and reception field strength on the vertical axis as information 2201-3 indicating reception field strength. In this line graph, five candidate threshold values are shown on the vertical axis, and the threshold value selected by the user (“3” in FIG. 22A) is highlighted.

  FIG. 22B is a screen of search device 1 in ST2014. In this screen, instead of the information 2201-2 indicating that the search target device 2 in FIG. 22A is within the watch range, information indicating that the search target device 2 has gone out of the watch range. (Character “Exceeded the watching range !!”) 2202-1 is displayed. Also, 2202-2 is displayed on this screen as information that prompts the user to switch to the individual search mode (characters “Do you want to search?”).

[Example of use]
FIG. 23 shows an example in which the search device 1 is installed and used near the entrance in the house in a removable state. In FIG. 23, it is assumed that the search device 1 is performing communication in the watching mode with the search target device 2 carried by the search target person # 2.

  In this case, the received signal strength of the radio wave in the searching device 1 peaks when the person to be searched for # 2 (searched device 2) comes near the entrance due to the door shut-off property, and decreases sharply when going outside. And below the threshold. Therefore, when searchee # 2 (searchee 2) goes out of the house (watching range), search device 1 immediately detects this and executes warning processing, and searches for searcher # 1. I can inform you.

[variation]
In the present embodiment, as shown in FIG. 24, one search device 1 communicates with the search target device 2 in the watch mode, and the other search device 1X monitors the watch mode communication. It is also possible to detect that 2 has come out of the watch range. In the example of FIG. 24, searcher # 1X carries search device 1X. Hereinafter, this variation will be described. Note that the communication mode of the search device 1X in this case is referred to as “watching monitoring mode”.

  In this variation, when the warning processing unit 131e of the search device 1 that executes the watch mode executes the warning process, the signal generation unit 131a includes the response confirmation signal in the watch mode with respect to the search target device 2. Always include warning instruction information.

[Additional function of search device]
When starting the monitoring mode, the signal generation unit 131a includes the identification information of the own device, the identification information of the search device 1 that performs communication in the monitoring mode, and the identification information of the search target device 2 to be monitored. A digital signal sequence (transmission frame) of the paging signal is generated.

  The signal acquisition unit 131b acquires the identification information of the search target device 2 from the received response confirmation signal in the monitoring mode and outputs it to the display unit 12 in the monitoring mode.

  In the monitoring mode, the warning processing unit 131e determines that the search target device 2 to be watched is within the watching range when the received warning mode response confirmation signal does not include warning instruction information. Information indicating that the communication in the monitoring mode is continued is output to the display unit 12. On the other hand, the warning processing unit 131e, when in the monitoring mode, if the received instruction confirmation information is included in the received response confirmation signal of the monitoring mode, the watched device 2 to be monitored is out of the monitoring range. It is estimated that it has come out, and information indicating that is output to the display unit 12 and a warning process is executed.

[Communication sequence]
FIG. 25 is a sequence diagram illustrating a state of communication between search device 1, search device 1X, and search target device 2 according to a variation of the present embodiment.

  The search device 1, the search device 1X, and the search target device 2 are in a standby state after being powered on. In search device 1, first, a search mode is selected.

  In the standby state, the search device 1 and the search target device 2 perform reception processing in the first period 321 (for example, 3 ms) at every first interval (for example, 3 s) (activated state). Then, in the first period 321, the searchee device 2 returns to the sleep state when the information requesting transmission of the identification information of the own device cannot be acquired.

  In the standby state, when the search device 1X is instructed by the user to execute the watch monitoring mode, the identification information of the search device 1 that performs communication in the watch mode and the identification information of the search target device 2 to be watched, the search state If the reception process is performed in the second period 311 (for example, 5 ms) and no radio wave is received from another search device 1 during the second period 311, the third period 312 is longer than the first interval. In (for example, 3.5 s), the watch monitoring mode call signal including the identification information of the own device, the identification information of the search device 1 that performs communication in the watch mode, and the identification information of the search target device 2 to be watched is repeatedly transmitted.

  When the search device 1 receives the watch signal for the watch mode during any of the first periods 321-3, the search device 1 transmits the call signal for the watch mode and starts the watch mode. Thereafter, the monitoring mode communication described above is performed between the search device 1 and the search target device 2. Note that the search device 1 performs reception processing at the first channel 321 on the radio frequency of the common channel at every first interval even after starting communication in the watch mode with the search target device 2.

  The search device 1X performs reception processing at the radio frequency of the common channel in the seventh period 315 (for example, 100 ms). Then, when the search device 1X receives the watch mode call signal transmitted from the search device 1 to the search target device 2, the search device 1X includes the timing immediately after the fourth period 322-1 specified by the timing information. A reception process is performed in the period 316-1 (for example, 100 ms), and a response confirmation signal in the watching mode transmitted from the search device 1 to the search target device 2 is intercepted.

  Thereafter, the communication system (search device 1 and searched device 2) repeats transmission / reception of the response signal in the monitoring mode and transmission / reception of the response confirmation signal in the monitoring mode until a disconnection instruction is received from the user. In addition, the search device 1 </ b> X repeats the intercept of the monitoring mode response confirmation signal transmitted from the search device 1 to the searched device 2.

  The search device 1 measures the received signal strength of radio waves each time a response signal in the watching mode is received. When the received signal strength of the radio wave is equal to or higher than a predetermined threshold, the search device 1 confirms that the identification information of the search target device 2 to be watched over and that the search target device 2 is within the watch range. Information to be displayed is displayed on the screen of the display unit 12. On the other hand, when the received signal strength of the radio wave is lower than a predetermined threshold, the search device 1 transmits the response confirmation signal in the watch mode including the warning instruction information, and the identification information of the search target device 2 to be watched, and Information indicating that the searchee device 2 has gone out of the watching range is displayed on the screen of the display unit 12 and a warning process is executed.

  If the warning confirmation information is not included in the response confirmation signal in the watching mode, the searching device 1X has the identification information of the searching target device 2 to be monitored and the searching target device 2 is within the watching range. Is displayed on the screen of the display unit 12. On the other hand, in the case where the warning instruction information is included in the response confirmation signal in the watching mode, the searching device 1X has the identification information of the searching target device 2 to be monitored and the searching device 2 is outside the watching range. Information indicating that it has appeared is displayed on the screen of the display unit 12 and a warning process is executed.

  Thereafter, the search device 1X transmits a call signal for the individual search mode when the user (searcher # 1X) instructs to search the search target device 2 to be watched over. In this case, as illustrated in FIG. 19, the searchee device 2 stops the monitoring mode response signal transmission processing, the monitoring mode response confirmation signal reception processing, and the reception processing at the radio frequency of the common channel. Then, the searchee device 2 transmits an individual search mode response signal to the search device 1X. Thereafter, the search device 1X performs communication in the individual search mode (communication sequence shown in FIG. 5) with the search target device 2.

  Further, when there is a disconnection instruction from the user (searcher # 1X), the search device 1X transmits a disconnection signal at the radio frequency of the common channel. When receiving the disconnection signal in the first period 321, the search device 1 performs a disconnection process with the search target device 2. The searching device 1 and the searched device 2 return to the standby state when the disconnection process is completed. When the search device 1X intercepts the disconnection response confirmation signal transmitted from the search device 1 to the searched device 2, the search device 1X returns to the standby state.

  In this variation, a dedicated device for watching (hereinafter referred to as “watching device”) that executes only the watching mode of the search device 1 may be used. In this case, the operation unit 13 and the like other than the configuration necessary for carrying out the communication sequence shown in FIG. 22 can be omitted from the monitoring device.

  Further, the antenna of the watching device can be configured to have directivity in a predetermined direction (patch antenna, Yagi antenna, etc.). In this case, depending on the directivity setting, the peak of the received signal strength of the radio wave in the watching device is further increased, and the received signal strength of the radio wave after the search target person # 2 (searched device 2) goes outside decreases. Becomes more rapid. Therefore, the watching device can detect sooner and surely that searchee # 2 (searched device 2) has gone out of the house (watching range).

[effect]
As described above, according to the present embodiment, the search device can detect and notify the user that the person who owns the search target device has gone out of the watching range. As a result, the user can quickly know that the situation that requires the search has been reached, thereby increasing the possibility of finding the search target person and reducing the time until discovery.

(Embodiment 4)
In an environment where the search device is near the ground and there are many obstacles (trees, buildings, etc.) between the search device and the search device, the communicable distance between the search device and the search device becomes short (for example, several hundreds). m) The search range is limited. On the other hand, if the search device is installed at a high place, there are almost no obstacles between the search device and the communicable distance between the search device and the search device becomes long (for example, several km). “Installing the search device at a high place” means that the search device is installed in addition to the case where the search device is fixedly installed at a point higher than a predetermined height from the ground, such as a tower or the roof of a building. This includes flying a radio controlled helicopter.

[Example of use]
In the fourth embodiment, as shown in FIG. 26, the radio wave from the search device 1 held by the searcher # 1 on the ground does not reach the search target device 2 carried by the search target person # 2 sufficiently, and When the search device 1 cannot communicate with the search target device 2, another search device (hereinafter referred to as “relay device”) 3 installed at a high place performs communication in the individual search mode with the search target device 2. A case where the search result (distance and direction of the search target device) is notified to the search device 1 will be described. In the present embodiment, the configurations of search device 1 and search target device 2 are the same as those described in the first embodiment, and a description thereof will be omitted. The relay device 3 has the same configuration as that of the search device 1. However, the search device 1 according to the present embodiment has a function for causing the search device 1 (FIG. 3) of the first embodiment to display the search result (distance and direction of the searched device) of the relay device 3. Added. Further, the relay device 3 is added with a function for notifying the search device 1 of the search result (distance and direction of the search target device) to the search device 1 (FIG. 3) of the first embodiment.

[Additional function of search device]
The signal acquisition unit 131b of the search device 1 acquires information indicating the search result (distance and direction of the search target device 2) from the response confirmation signal from the relay device 3, and outputs the information to the display unit 12.

[Additional relay device functions]
In the individual search mode, the signal generation unit 131a of the relay device 3 confirms the identification information of the searched device 2, the identification information of the own device, and information indicating the search result (distance and direction of the searched device 2). Include in

[Communication sequence]
FIG. 27 is a sequence diagram showing how the search apparatus 1, search target apparatus 2, and relay apparatus 3 communicate according to the present embodiment.

  The search device 1, the searchee device 2, and the relay device 3 are in a standby state after being powered on. In relay device 3, the search mode is initially selected.

  In the standby state, the relay device 3 and the searched device 2 perform reception processing in the first period 321 (for example, 3 ms) at every first interval (for example, 3 s) (activated state). Then, in the first period 321, the searchee device 2 returns to the sleep state when the information requesting transmission of the identification information of the own device cannot be acquired.

  In the standby state, when the search device 1 is instructed by the user for the identification information of the search target device 2 to be searched, the search device 1 enters the search state, performs reception processing in the second period 311-1 (for example, 5 ms), When the radio wave from the other search device 1 is not received during the period 311-1, the call signal for the individual search mode is repeatedly transmitted in the third period 312 (for example, 3.5 s) longer than the first interval. To do. The search device 1 performs reception processing in the fifth period 313-1 (for example, 5 ms) including the timing specified by the timing information included in the call signal.

  Here, it is assumed that the paging signal transmitted from the search device 1 is received by the relay device 3 but not received by the search target device 2.

  The relay device 3 performs reception processing in the fifth period 313-1 (for example, 5 ms) including the timing specified by the timing information included in the call signal. If the relay apparatus 3 does not receive a call response signal from the search apparatus 2 to the search apparatus 1 in this fifth period, the call signal transmitted from the search apparatus 1 is not received by the search apparatus 2 and the search apparatus 2 The device 1 recognizes that it cannot communicate with the searched device 2. Therefore, the relay device 3 starts communication in the individual search mode with the searched device 2 instead of the search device 1. Specifically, the relay device 3 repeatedly transmits the call signal for the individual search mode in the third period 312-2 immediately after the fifth period 313-1.

  Since the search device 1 receives the call signal from the relay device 3 in the second period 311-2 immediately after the fifth period 313-1, the relay device 3 starts communication in the individual search mode with the search target device 2. You can know what you did. In this case, the search device 1 stops transmission of the calling signal.

  When the searchee device 2 receives the watch mode call signal during any of the first periods 321-3, the radio frequency of the dedicated channel in the fourth period 322-1 (for example, 2 ms) specified by the timing information. Then, a response signal including the identification information of the own device and the identification information of the relay device 3 of the communication partner is transmitted.

  The relay device 3 performs reception processing in the fifth period 313-2 (for example, 5 ms). Then, as soon as the relay device 3 receives the response signal, in the sixth period 314-1 (for example, 2 ms), the relay device 3 uses its own channel identification information, the identification information of the searched device 2 and the search at the radio frequency of the dedicated channel. A response confirmation signal including information indicating the result (distance and direction of the search target device 2) is transmitted.

  The searched device 2 performs reception processing in a seventh period 323-1 (for example, 3 ms) immediately after the fourth period 322-1. And the to-be-searched apparatus 2 will transmit a response signal again in the 4th period 322-2 after the 2nd space | interval (for example, 100 ms) passes, if a response confirmation signal is received.

  The search device 1 intercepts the response confirmation signal transmitted from the relay device 3 in the fifth period 313-2 (for example, 100 ms). Since the response confirmation signal includes the identification information of the searched device 2 and the identification information of the relay device 3, the searching device 1 recognizes that the searched device 2 is communicating with the relay device 3. can do. In addition, the search device 1 acquires and displays information indicating a search result (distance and direction of the search target device 2) included in the response confirmation signal transmitted from the relay device 3. Thereby, searcher # 1 can know the distance and direction of search target device 2 carried by search target person # 2.

  Thereafter, the relay device 3 and the searched device 2 repeat transmission / reception of a response signal and transmission / reception of a response confirmation signal until a disconnection instruction is received from the user. The search device 1 continues to intercept the response confirmation signal transmitted from the relay device 3.

  In the individual search mode of the present embodiment, the relay device 3 performs reception processing at the radio frequency of the common channel in the first period 321 (for example, 3 ms) every second interval (for example, 100 ms).

  When receiving a disconnection instruction from the user, the search device 1 transmits a disconnection signal at the radio frequency of the common channel. When the relay device 3 receives the disconnection signal in the first period 321, the relay device 3 performs a disconnection process with the searched device 2. The relay device 3 and the searched device 2 return to the standby state when the disconnection process is completed. When the search device 1 intercepts the disconnection response confirmation signal transmitted from the relay device 3 to the searched device 2, the search device 1 returns to the standby state.

  In the present embodiment, the antenna of the relay apparatus 3 may be a sector antenna, and the relay apparatus 3 may estimate the azimuth (absolute direction) of the searched apparatus 2 from the received signal strength of the radio wave of each antenna element. . Here, the sector antenna uses a plurality of directional antenna elements, and each antenna element is arranged so as to cover all 360 ° directions of the horizontal plane.

  Further, the search device 1 estimates the direction of the search target device 2 viewed from the own device based on the direction of the search target device 2 received from the relay device 3 and the current direction of the own device, and the estimated search target device Information regarding the two directions may be displayed.

[variation]
In the present embodiment, as shown in FIG. 28, when the search device 1 cannot communicate with the search target device 2, any one of a plurality (four in the example of FIG. 28) of relay devices 3 is searched. The search result (distance and direction of the search target device) may be notified to the search device 1 via the other relay device 3. Each circle shown in FIG. 28 indicates a range in which a radio wave transmitted from a device at the center reaches a predetermined level (a level at which a communication partner can receive). For example, since relay device 3-1 exists in a circle centered on search device 1, it can receive a signal from search device 1 at a predetermined level and acquire information included in the received signal. . On the other hand, since relay devices 3-1, 3-2, 3-3, 3-4 exist outside the circle centered on search device 1, the signals from search device 1 are received at a predetermined level. The information contained in the received signal cannot be acquired.

  In FIG. 28, the relay device 3-1 receives the call signal from the search device 1 and performs reception processing on the call response signal from the searched device 2 during a period specified by the timing information included in the call signal. . When the relay apparatus 3-1 does not receive a call response signal from the search apparatus 2 to the search apparatus 1, the call signal transmitted from the search apparatus 1 is not received by the search apparatus 2, and the search apparatus 1 Recognize that communication with the search device 2 has failed. Therefore, the relay device 3-1 transmits a call signal and attempts to start communication in the individual search mode with the searched device 2.

  The relay device 3-2 receives the call signal from the relay device 3-1, and performs reception processing on the call response signal from the searched device 2 in a period specified by the timing information included in the call signal. When the relay device 3-2 does not receive a call response signal from the searchee device 2 to the relay device 3-1, the call signal transmitted from the relay device 3-1 is not received by the searchee device 2, and relaying is performed. The device 3-1 recognizes that it cannot communicate with the searchee device 2. Therefore, the relay device 3-2 transmits a call signal and attempts to start communication in the individual search mode with the searched device 2.

  Thereafter, similarly, the relay device 3-3 recognizes that the relay device 3-2 cannot communicate with the searched device 2, transmits a call signal, and starts communication in the individual search mode with the searched device 2. Try to do. The relay device 3-4 recognizes that the relay device 3-3 cannot communicate with the searched device 2, transmits a call signal, and tries to start communication in the individual search mode with the searched device 2.

  Since the searched device 2 exists in a range where radio waves of the relay device 3-4 reach at a communicable level, the relay device 3-4 can communicate with the searched device 2 in the individual search mode. The relay device 3-4 and the searched device 2 repeat transmission / reception of a response signal and transmission / reception of a response confirmation signal. The response confirmation signal includes identification information of the searched device 2, identification information of the relay device 3-4, and information indicating a search result (distance and direction of the searched device 2).

  The relay device 3-3 can recognize that the searched device 2 is communicating with the relay device 3-4 by intercepting the response confirmation signal transmitted from the relay device 3-4. The relay apparatus 3-3 transmits the intercepted response confirmation signal as it is. Thereby, the relay apparatus 3-2 can intercept the response confirmation signal transmitted from the relay apparatus 3-4.

  Hereinafter, similarly, the relay device 3-2 and the relay device 3-1 transmit the intercepted response confirmation signal as it is. Thereby, the search device 1 can intercept the response confirmation signal transmitted from the relay device 3-4.

[effect]
As described above, according to the present embodiment, the relay device searches for the searched device instead of the searching device, and notifies the searching device (user) of the search result (distance and direction of the searched device). it can. Accordingly, the user can know the position of the search target device even if the search target device does not exist in a range in which the search target device can communicate with the search device, thereby increasing the possibility of finding the search target person. Can be shortened.

  The relay device according to the above embodiment is a relay device that performs direct wireless communication with a portable search device and directly performs wireless communication with a portable search device. Transmitting means for transmitting signals, receiving means for receiving signals from the searching device or the searched device, and control means for controlling the transmitting means and the receiving means, the control means comprising: The receiving means does not receive the first response signal corresponding to the first call signal from the searched device after receiving the first call signal including the identification information of the searched device from the searching device. In this case, the transmission means transmits a second call signal including identification information of the searched device, receives a second response signal from the searched device corresponding to the second call signal, and With response signal Estimating the distance between the machine and the search target device and the direction of the search target device, corresponding to the second response signal, and causing the transmission means to transmit a response confirmation signal including information on the estimated distance and direction. Take the configuration.

  The search device of the above embodiment is a portable search device that performs wireless communication with the relay device described above and directly performs wireless communication with a portable search target device, and the response confirmation Control that estimates the distance between the device itself and the device to be searched and the direction of the device to be searched as viewed from the device based on information on the distance and direction included in the signal, and displays information on the estimated distance and direction Means.

  The search device of the above embodiment is a portable search device that performs direct wireless communication with a portable search target device, a transmission unit that transmits a signal to the search target device, and the transmission Receiving a signal from the searched device corresponding to the signal transmitted from the means, and calculating a propagation delay time of a transmission path between the receiving device that measures the received signal strength and the searched device; According to the magnitude of the signal strength, either the first distance estimation method based on the received signal strength or the second distance estimation method based on the propagation delay time is selected, and the distance between the own device and the search target device is selected. And a control unit that estimates and displays information on the estimated distance.

  In the search device of the above embodiment, the control means estimates the distance using the first distance estimation method when the received signal strength is greater than a predetermined threshold, and is less than or equal to the threshold. The second distance estimation method is used to estimate the distance.

  In the search device of the above-described embodiment, the control unit uses the first distance estimation method when the received signal strength is greater than a first threshold when the control unit used the first distance estimation method last time. The distance is estimated using the second distance estimation method when the distance is equal to or less than the first threshold, and the received signal is used when the second distance estimation method is used last time. The first distance estimation method is used to estimate the distance when the intensity is greater than a second threshold value that is greater than the first threshold value, and the second distance estimation method is used when the intensity is less than or equal to the second threshold value. And adopting a configuration for estimating the distance.

  The search device of the above embodiment is a portable search device that directly performs wireless communication with a portable search target device, and includes an antenna that transmits and receives radio waves, and the search target device via the antenna. Transmitting means for transmitting a signal to the receiving apparatus; receiving means for receiving a signal from the searched device corresponding to a signal transmitted from the transmitting means via the antenna; and measuring received signal strength; and the received signal Control means for estimating the direction of the device to be searched as viewed from its own device using intensity, and displaying information on the estimated direction, wherein the antenna is connected to the transmission means or the via the first switch. A first element connected to the receiving means; a second element arranged substantially parallel to the first element and connected to the housing via a second switch; and substantially parallel to the first element versus A third element disposed on the opposite side of the second element and connected to the housing via a third switch, wherein the receiving means connects the second switch and shuts off the third switch The received signal strength is measured in each of the first state and the second state in which the second switch is shut off and the third switch is connected, and the control means measures the received signal in the measured first state. A configuration is adopted in which the direction of the searched device is estimated based on the magnitude relationship between the strength and the received signal strength in the second state.

  Further, the search device of the above embodiment divides the numerical value of the difference between the received signal strength in the first state and the received signal strength in the second state into a plurality of ranges, and the range of the searched device is divided into each range. A table in which representative values of estimated directions are associated is stored in a memory, and the control means represents a representative corresponding to a range including the measured received signal strength in the first state and the received signal strength in the second state. A configuration is adopted in which information indicating a value is displayed on the screen as information on the estimated direction.

  The search device of the above embodiment is a portable search device that directly performs wireless communication with a portable search target device, and includes an antenna that transmits and receives radio waves, and the search target device via the antenna. Transmitting means for transmitting a signal to the receiving apparatus; receiving means for receiving a signal from the searched device corresponding to a signal transmitted from the transmitting means via the antenna; and measuring received signal strength; and the received signal Control means for estimating the direction of the device to be searched as viewed from its own device using intensity, and displaying information on the estimated direction, wherein the antenna is capable of directional reception, and the receiving means Measuring the received signal strength at each of a plurality of directivities, and the control means estimates the direction of the searched device based on a plurality of received signal strength measurements at each directivity. Take the deposition.

  Further, in the search device of the above embodiment, the control means averages a plurality of received signal strength measurement values for each directivity, and based on the average value of the received signal strength of each directivity, Take the configuration to estimate the direction.

  The search device of the above embodiment is a portable search device that directly performs wireless communication with a portable search target device, and includes an antenna that transmits and receives radio waves, and the search target device via the antenna. Transmitting means for transmitting a signal to the receiving apparatus; receiving means for receiving a signal from the searched device corresponding to a signal transmitted from the transmitting means via the antenna; and measuring received signal strength; and the received signal Control means for estimating the direction of the device to be searched as viewed from its own device using intensity, and displaying information on the estimated direction. The control means includes a plurality of preset direction candidates. Then, a configuration is used in which a device closest to the direction of the device to be searched as viewed from its own device is estimated, and a direction that is one step closer to the currently estimated direction than the previously displayed direction is displayed.

  The search device of the above embodiment is a portable search device that directly performs wireless communication with a portable device to be searched, and is stored in the portable case and the case, and transmits and receives radio waves. Receiving a signal from the searched device corresponding to a signal transmitted from the transmitting means via the antenna, a transmitting means for transmitting a call signal to the searched device via the antenna Information on the estimated distance and direction, estimating the distance between the own device and the searched device and the direction of the searched device viewed from the own device using the signal received by the receiving means Control means for displaying the operation button, the operation button is disposed on a first end side of the first surface of the housing from the center of the housing, and the antenna is disposed from the center of the housing. On the opposite side of the first end That is disposed on the second end side, concave or convex portion in the center or side of the second surface is provided which is opposite to the first surface, a configuration.

  The search device of the above embodiment is a search device capable of communicating with a plurality of search target devices, and includes a transmission means for transmitting a call signal to the search target device, and the search target corresponding to the call signal. Receiving means for receiving a response signal from the search device; and control means for displaying identification information of the search target device that has transmitted the response signal. A configuration is adopted in which a paging signal for transmitting a response signal to the searched device or a paging signal for transmitting response signals to a plurality of searched devices is selectively generated and output to the transmitting means.

  In addition, in the search device of the above embodiment, when one search target device is instructed as a search target by the user, the control unit is configured to identify the own device identification information, the search target search device identification information, The paging signal including information requesting the searched device to transmit identification information and timing information indicating the transmission timing of the response signal to the searched device is generated and output to the transmitting means, and the receiving device A means takes the structure which receives the said response signal in the time including the transmission timing of the said timing information.

  In addition, in the search device of the above embodiment, when the user instructs all search target devices as search targets, the control unit identifies the identification information of the own device and all the search target devices. Generating the paging signal including information for requesting transmission of information and outputting the paging signal to the transmitting unit; and the receiving unit receives the response signal for a predetermined time after the paging signal is transmitted. Take.

  In the search device of the above embodiment, when a plurality of search target devices registered in advance are instructed as search targets by the user, the control means includes the identification information of the own device and the pre-registered multiple Generating a call signal including information requesting transmission of identification information to the searched device and outputting the call signal to the transmission means, and the reception means for a predetermined time after the call signal is transmitted. The response signal is received.

  In addition, in the search device of the above embodiment, when the user gives an instruction to operate as the search target device, the reception unit receives the call signal from another search device, and the control unit The response signal including the identification information of the machine and the identification information of the other search device is generated and output to the transmission means, and the transmission means sends the response signal for the call signal to the other search device. Send, take the configuration.

  The present invention is suitable for use in a search device for searching for the position of another communication device, and a communication system including a search device and a searched device.

DESCRIPTION OF SYMBOLS 1 Search apparatus 2 Searched apparatus 11, 21 Case 12 Display part 13 Operation part 14, 23 Power switch 15 Board | substrate 16 Recessed part 22 LED
101, 201 Antenna 102, 202 Radio section 103, 203 Control section 104, 204 Ring section 105, 205 Battery (power supply section)
111 First antenna element 112 Second antenna element 113 Third antenna element 121, 221 Transmitter 122, 222 Receiver 123, 223 Radio controller 124, 224 First clock 125, 225 First switch 126 Second switch 127 Third Switch 131,231 CPU
131a, 231a Signal generation unit 131b, 231b Signal acquisition unit 131c Distance estimation unit 131d Direction estimation unit 132, 232 Memory unit 133, 233 Second clock 134, 234 Third clock 135 Logic operation unit

Claims (5)

A portable search device that performs direct wireless communication with a portable search target device,
Transmitting means for transmitting a signal to the searched device;
Receiving means for receiving a signal from the searched device corresponding to the signal transmitted from the transmitting means and measuring received signal strength;
When the received signal strength is greater than or equal to a predetermined threshold value, the transmitting means and the receiving means are controlled to continue the transmission process and the receiving process, and when the received signal strength falls below the threshold value, the user is notified of the abnormality. Control means for performing warning processing for
A search device comprising: The warning process is
It is at least one of outputting a warning sound from the speaker of the ringing unit, vibrating the apparatus body, and blinking the display of the display unit.
The search device according to claim 1. A communication system comprising a portable search device and a portable search target device that performs wireless communication with the search device,
The search device includes:
First transmission means for transmitting a signal to the searched device;
First receiving means for receiving a signal from the searched device and measuring received signal strength;
When the received signal strength is greater than or equal to a predetermined threshold, the first transmitting means and the first receiving means are controlled to continue transmission processing and reception processing, and when the received signal strength falls below the threshold, the user First control means for performing a first warning process for notifying an abnormality to
Comprising
The searched device is:
Second receiving means for receiving a signal from the search device;
Second control means for generating a signal corresponding to the signal received by the second receiving means;
Second transmission means for transmitting the signal generated by the second control means;
Comprising
Communications system. The first control means includes warning instruction information for instructing the searched device to execute a second warning process for notifying a user of the searched device when the received signal strength is lower than the threshold. Transmitting to the first transmission means;
The second control means executes the second warning process when the warning instruction information is received.
The communication system according to claim 3. The second warning process is
Output at least one of the sound recorded from the speaker of the ringing unit, vibrate the device body, and blink the light emitting unit.
The communication system according to claim 4.

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