JP2018042059A - SEARCH DEVICE, RELAY DEVICE, AND SEARCH METHOD - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the possibility of finding a search target person and shorten the time until the search target person is found as compared with the conventional one. A search device 1 transmits a search instruction signal to a relay device 3A. When the relay device 3A receives the search instruction signal from the search device 1, the relay device 3A repeatedly transmits the call signal. Upon receiving the call signal from the relay device 3A, the searched device 2 transmits a call response signal including the identification information of the own device and the identification information of the relay device 3 of the communication partner. After receiving the call response signal, the relay device 3A transmits a response confirmation signal to the search device 2, and transmits a search result signal indicating that the search device 2 has been found to the search device 1. After receiving the search result signal from the relay device 3A, the search device 1 displays the identification information of the search device 2, the information indicating that the search device 2 has been found, and the distance to the search device 2. [Selection diagram] FIG. 15

Description

  The present invention relates to a search device that searches for a search target device, a relay device that searches for the search target device in cooperation with the search device, and a search method for the search target device using the search device and the search target 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. (For example, Patent Document 1, Patent Document 2, Non-Patent Document 1).

  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 (for example, Patent Document 3 and Patent Document 4).

JP 2003-198389 A JP 2005-229449 A JP 2010-147536 A Japanese Patent No. 5891468

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, a relay device, and a search method are provided.

  The search device of the present invention is a portable search device that performs wireless communication directly with a portable search target device and performs wireless communication with a relay device that performs wireless communication with the search target device. A transmitting unit that transmits a search instruction signal including identification information of a search device and identification information of the relay device to the relay device, and a search result signal including information indicating a search result of the searched device is received from the relay device. A receiving unit; and a display unit that displays information indicating a search result of the search target device.

  A relay device according to the present invention is a relay device that performs wireless communication with a portable search device and wirelessly communicates with a portable search device that performs wireless communication with the search device. A receiving unit that receives a search instruction signal including identification information and identification information of the relay device from the searching device; and a receiver that receives the search instruction signal and then receives a calling signal including the identification information of the searched device. A transmitting unit for transmitting to the receiver, wherein the receiving unit receives a response signal corresponding to the call signal from the searched device, and based on whether or not the response signal has been received, The information processing apparatus further includes a control unit that generates information indicating a search result, and the transmission unit transmits a search result signal including information indicating a search result of the search target device to the search device.

  The search method of the present invention includes the search device of a communication system including a portable search device, a portable search device, and the search device and a relay device that performs wireless communication with the search target device. And a search method of the searched device by the relay device, wherein the search device transmits a search instruction signal including identification information of the searched device and identification information of the relay device to the relay device, and the relay device After receiving the search instruction signal, a device transmits a paging signal including identification information of the searched device to the searched device, and the relay device transmits a response signal corresponding to the paging signal to the searched device. When the signal is received, the signal indicating the search result of the searched device is transmitted to the searching device.

  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 in the separate search mode with the search device and search target device concerning Embodiment 1 of this invention. The sequence diagram which shows the mode of communication in the all-search mode with the search device and search target device concerning Embodiment 1 of this invention. Diagram showing the relationship between distance and received signal strength 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 the relationship between the distance between the apparatuses which perform radio | wireless communication, and received power The figure which shows the example of arrangement | positioning of the relay apparatus which concerns on Embodiment 2 of this invention. The block diagram which shows the structure of the relay apparatus which concerns on Embodiment 2 of this invention. The figure which shows the usage example of the communication system which concerns on Embodiment 2 of this invention. The sequence diagram which shows the mode of communication in the separate search mode of the search device, searchable device, and relay device which concerns on Embodiment 2 of this invention. The sequence diagram which shows the mode of communication in all the search modes of the search apparatus, to-be-searched apparatus, and relay apparatus which concern 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 figure which shows the antenna structure of the relay apparatus which concerns on the variation 1 of Embodiment 2 of this invention. External view of searched device according to variation 2 of embodiment 2 of the present invention The sequence diagram which shows the mode of communication of the search apparatus which concerns on the variation 2 of Embodiment 2 of this invention, a to-be-searched apparatus, and a relay apparatus The figure which shows the usage example of the communication system which concerns on the variation 3 of Embodiment 2 of this invention. The figure which shows the usage example of the communication system which concerns on the variation 4 of Embodiment 2 of this invention. The figure which shows the usage example of the communication system which concerns on the variation 5 of Embodiment 2 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) The individual search mode is a mode in which the search device 1 performs wireless communication with the single searched device 2 instructed by the user and estimates the relative position (distance) of the single searched device 2. is there. 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. Various circuits (see FIG. 3) are placed on the substrate 15.

  The antenna 101 is patterned on the plane 11e side (upper end side) from the center of the substrate 15. The length of the antenna 101 is 1/4 (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 antenna 101 is about 81.5 mm.

  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 201 (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, and a first switch 125.

  The transmission unit 121 performs wireless transmission processing such as modulation, amplification, and up-conversion on the baseband digital signal output from the CPU 131, and transmits the wireless signal from the antenna 101. 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 antenna 101 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 antenna 101 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.

  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 antenna 101 in accordance with an instruction from the radio 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, and a distance estimation unit 131c 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 generates a digital signal (calling signal, response confirmation signal) including the identification information of the single searched device 2 instructed by the user and the identification information of the own device. The signal generation unit 131a generates a digital signal (calling signal) including information indicating that transmission of response signals is requested to all the search target devices 2 in the all search mode. In the group search mode, the signal generation unit 131a generates a digital signal (calling signal) including identification information of all search target devices 2 belonging to the group designated by the user. When the signal generation unit 131a receives information requesting transmission of identification information of the own device from the signal acquisition unit 131b in the search mode, the signal generation unit 131a includes the identification information of the own device and the identification information of the communication partner search device 1. A signal (response signal) is generated. 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.

  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 communication mode other than the search mode, and outputs the identification information to the display unit 12. In the search mode, the signal acquisition unit 131b acquires information from the digital signal sequence (received 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.

[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. (Response signal)) is generated 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 searched device 2 returns to the sleep state when it cannot acquire the call signal including its own identification information.

  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 of the search target device 2 using the response signal, and displays identification information of the search target device 2 and information on the distance of the search target device 2 on the display unit 12. It is displayed on the screen (see FIG. 8E).

  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 between search device 1 and search target device 2 according to the present embodiment in full search mode 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.

[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. 8A is a screen at the start of 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. 8B is a screen at the start of the individual search mode when the search for the unregistered search target device 2 is started. 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. 8C 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 full search mode (see FIG. 6).

  FIG. 8D 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. 8E is a screen when the individual search mode is executed and a response signal is received from the searchee device 2. On this screen, identification information 1005-1 of the searched device 2 that has responded, information 1005-2 regarding the distance to the searched device 2, and the like are displayed on the screen.

  FIG. 8F 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. 9A and FIG. 9B.

  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). In addition, search device 1 measures the received signal strength of the response signal (ST1111), and estimates the distance to searched device 2 (ST1112). Then, search device 1 displays the identification information of search target device 2 and the information related to the distance of search target device 2 on the screen of display unit 12 (ST1113).

  Thereafter, if there is no instruction to end the search from the user (ST1114: NO), and the timer does not end after counting a predetermined time (ST1115: NO), the search device 1 performs the reception process again at a predetermined interval ( ST1116).

  When the response signal cannot be received in ST1116 (ST1117: NO), search device 1 repeats steps ST1114 to ST1116. On the other hand, if a response signal can be received in ST1116 (ST1117: YES), the flow returns to ST1110, and search device 1 repeats steps ST1110 to ST1116 (communication state).

  In this communication state, when the user gives an instruction to end the search (ST1114: YES), or when the timer ends by measuring a predetermined time (ST1115: YES), the search device 1 transmits a disconnection signal, Disconnection processing of receiving a disconnection response signal and transmitting a disconnection confirmation signal is performed (ST1118). 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, if the instruction from the user is the search mode (ST1102: search mode), the flow proceeds to ST1201 in FIG. 10, 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.

  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.

  Further, in the above-described embodiment, a case has been described in which information related to the estimated distance of the search target device 2 is displayed on a screen such as an LCD of the search device 1, but the present invention is not limited to this, and the case of the search device 1 is not limited thereto. Other display methods such as providing a plurality of LEDs on the front of the body 11 and changing the position of the LED to emit light according to the distance of the search target device 2 may be used.

  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.

(Embodiment 2)
FIG. 11 is a diagram illustrating a relationship between a distance (horizontal axis) between apparatuses performing wireless communication and received power (vertical axis). Graphs G1, G2, G3, and G4 show cases where the apparatus is placed on the ground at 10 cm, 1 m (standard height when used by the user), 2 m, and 10 m, respectively.

  As shown in FIG. 11, in wireless communication, the closer the position of the device is to the ground, the stronger the influence of reflected waves from the ground, so the radio wave attenuation increases and the communicable distance (the distance at which received power greater than a predetermined value is obtained). ) Becomes shorter. Further, if the height of the device from the ground is x times, the communicable distance becomes √x times (when x = 10, the communication distance becomes about 3.2 times). For example, the distance at which received power of −100 dBm can be obtained is about 250 m for G1, about 800 m for G2, about 1200 m for G3, and about 2550 m for G4.

  In an environment where many obstacles (trees, buildings, etc.) exist between devices, the communicable distance is further shortened.

  If the search device 1 is arranged at a high place, the influence of the ground reflected wave is reduced, and there is almost no obstacle between the search device 2 and the communicable distance between the search device 1 and the search device 2 The searchable area can be expanded by lengthening.

  However, since the search device 1 is operated while the user holds it in his hand and looks at the screen, it is difficult to perform a search with the search device 1 placed at a high place.

  Accordingly, the present inventor has conceived of expanding the searchable area by adding a relay device that relays between the search device 1 and the searched device 2 to the communication system and arranging the relay device at a high place. did.

  Hereinafter, a second embodiment of the present invention embodying this idea will be described in detail with reference to the drawings. The communication system according to the present embodiment employs a configuration in which one or more relay devices 3 (see FIG. 13) are added to the communication system of the first embodiment. In the present embodiment, search device 1 and searched device 2 perform wireless communication with each relay device 3. Each relay device 3 is arranged at a high place, searches the searched device 2 in accordance with an instruction from the search device 1, and notifies the search device 1 of the search result.

  Note that “disposing the relay device 3 at a high place” is not limited to the case where the relay device 3 is fixedly installed at a point higher than a predetermined height from the ground, such as a steel tower or the roof of a building. As shown, the case where the relay apparatus 3 is temporarily placed at a high place is also included. FIG. 12 (A) shows an example in which a long rod X1 with the relay device 3 attached to the tip portion is raised, and FIG. 12 (B) shows an example in which the balloon X2 with the relay device 3 attached is raised to the sky. FIG. 12C shows an example in which the drone X3 equipped with the relay device 3 is blown up. FIG. 12D shows an example in which a rod X1 equipped with the relay device 3 is set up on a ship X4 or the like when searching at sea. In the example of FIG. 12D, when the rod X1 with the relay device 3 attached is placed on the sea, a weight (not shown) and a balloon (floating) X2 are attached to the rod X1.

[Additional functions of search device 1]
In the present embodiment, the configuration of the search device 1 is the same as that described in the first embodiment. However, in the present embodiment, the following function for displaying the search result of the relay device 3 is added to the signal generation unit 131a and the signal acquisition unit 131b of the CPU 131.

  In the individual search mode, the signal generation unit 131a generates a digital signal (search instruction signal) including its own identification information, the identification information of the relay device 3, and the identification information of the search target device 2 to be searched. Further, in the all search mode, the signal generation unit 131a includes digital identification information including identification information of the own device, identification information of the relay device 3, and information indicating that transmission of response signals is requested to all the searched devices 2. A signal (search instruction signal) is generated. Further, in the group search mode, the signal generation unit 131a includes a digital signal including identification information of its own device, identification information of the relay device 3, and identification information of all search target devices 2 belonging to the group instructed by the user. Search instruction signal).

  Further, in all communication modes, the signal generation unit 131a generates a digital signal (result confirmation signal) including the identification information of the own device and the identification information of the relay device 3 after receiving the search result signal from the relay device 3. .

  The signal acquisition unit 131b acquires the identification information of the relay device 3 included in the notification signal from the relay device 3, and displays the identification information on the screen of the display unit 12. Further, the signal acquisition unit 131b acquires, from the search result signal from the relay device 3, the identification information of the searched device 2, information indicating that the searched device 2 has been found, and the distance to the searched device 2. To the display unit 12.

[Configuration of Relay Device 3]
Next, the circuit configuration of the relay device 3 will be described with reference to FIG. FIG. 13 is a block diagram showing a configuration of relay apparatus 3 according to the present embodiment. The relay device 3 employs a configuration in which the display unit 12, the operation unit 13, and the ringing unit 104 are deleted from the search device 1 (FIG. 3) according to the first embodiment. Note that the battery 105 of the relay device 3 may be a solar battery.

  The relay device 3 includes a CPU 331 having a function different from that of the CPU 131 instead of the CPU 131 of the search device 1. The CPU 331 includes a signal generation unit 331a, a signal acquisition unit 331b, and a distance estimation unit 331c as functions according to the present invention.

  The signal generation unit 331a generates a digital signal (notification signal) including identification information of the own device. In addition, in the individual search mode, the signal generation unit 331a directs the search target device 2 to the search target device 2 with a digital signal (calling) including the identification information of the search target device 2 to be searched and the identification information of the own device. Signal, response confirmation signal). Further, in the individual search mode, the signal generation unit 331a directs its own identification information, identification information of the search target device 2 to be searched, search results (whether or not the search target device 2 has been found) toward the search device 1. ) And information indicating the distance of the search target device 2 are generated. Further, in the all search mode, the signal generation unit 331a generates a digital signal (calling signal) including information requesting transmission of response signals from all the search target devices 2 and identification information of the own device. Further, in the group search mode, the signal generation unit 331a generates a digital signal (calling signal) including identification information of all search target devices 2 belonging to the group instructed by the search device 1 and identification information of the own device.

  The signal acquisition unit 331b acquires identification information of the search target device 2 from the digital signal sequence (reception frame) of the response signal received from the search target device 2, and outputs the identification information to the signal generation unit 331a.

  The distance estimation unit 331c 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. Then, the estimated value is output to the signal generation unit 331a.

[Usage example of communication system]
Next, an arrangement example of the relay device according to the present embodiment will be described with reference to FIG. FIG. 14 shows an example in which the search target device 2 is searched by formation of one search device 1 and four relay devices 3A, 3B, 3C, and 3D.

14A, _assume that the relay device 3 is arranged such that the height H3 _fst of the relay device 3 from the ground (at sea) is 10 times the height H1 of the search device 1 (for example, H3 _fst = 10 m, H1 = 1 m). In this case, if the radius R1 of the communicable region ( _searchable region) E1 of the search device 1 is 1 km, the radius R3 of the communicable region E3 _fst of the relay device 3 is 3.2 km that is √10 times the radius R1. . Therefore, the _searchable area ET _fst of the entire communication system can be expanded to about 32 times (10 km square) by arranging each relay device 3 in four directions from the search device 1 to the position of L3 _fst = 3.2 km.

In FIG. 14A, the searched device 2 transmits a response signal in response to the calling signal from the relay device 3D, and the relay device 3D sends information indicating that the searched device 2 has been found to the searching device 1. It is assumed that a search result signal including this is transmitted. In this case, since the information indicating that the relay device 3D has found the searched device 2 is displayed on the screen of the search device 1 (see FIG. 17B), the user of the search device 1 can select the relay device 3D. It can be seen that the searched device 2 exists in the communicable area E3 _fst D.

Therefore, the user of the search device 1 sets the area E3 _fst D as the search target area, and at the point where the relay device 3D is located (the center of the area E3 _fst D), as shown in FIG. Move with one. In addition, the user of each relay device 3 arranges each relay device 3 on all sides of the search device 1. At this time, each _searchable area of the entire communication system by all of the relay apparatuses 3 covers the area E3D _fst , and each communicable area E3 _snd of each relay apparatus 3 is smaller than the previous area E3 _fst. The distance L3 _snd between the relay device 3 and the search device 1 is made shorter than the previous distance L3 _fst , and the height H3 _snd of each relay device 3 is made lower than the previous height H3 _fst (for example, L3 _snd = 1). 0.8 km, H3 _snd = 3 m). Alternatively, the radio field intensity of each relay device 3 may be lowered by keeping the height H3 _snd of each relay device 3 the same as the previous time.

  As a result, any relay device 3 (relay device 3D in FIG. 14B) having a smaller communicable area than the previous time can receive a response signal from the searched device 2. The user can further narrow the search target area and finally discover the searched device 2.

[Communication sequence in individual search mode]
Next, communication in the individual search mode of search device 1, search target device 2, and relay device 3 according to the present embodiment will be described using the sequence diagram of FIG. FIG. 15 shows an example in which one search target device 2 is searched by formation of one search device 1 and two relay devices 3A and 3B. In FIG. 15, it is assumed that the searchee device 2 exists in the communicable area of the relay device 3A.

  Search device 1, searched device 2, and relay devices 3A and 3B are in a standby state after being powered on.

  In the standby state, the search device 1 performs reception processing in the first period 411 (for example, 3 ms) at every first interval (for example, 3 s) (starting state). And the search apparatus 1 returns to a sleep state, when the call signal containing the identification information of an own machine cannot be acquired during the 1st period 411.

  In the standby state, the searchee device 2 performs reception processing in the second period 421 (for example, 3 ms) at every first interval (for example, 3 s) (activated state). Then, in the second period 421, the searchee device 2 returns to the sleep state when it cannot acquire a call signal including its own identification information.

  In the standby state, the relay apparatuses 3A and 3B transmit notification signals including their own identification information in the third period 431 (for example, 2 ms) every first interval (for example, 3 s), and immediately after the third period 431. In the fourth period 432 (for example, 3 ms), reception processing is performed (activated state). Then, the relay devices 3A and 3B return to the sleep state when the search instruction signal (described later) from the search device 1 cannot be acquired during the fourth period 432.

  In the standby state, when the search device 1 is instructed by the user to identify the search target device 2 to be searched, in the fifth period 412 (for example, 3.5 s) longer than the first interval, the relay device 3A, Reception processing is performed until a notification signal is received from any of 3B. Then, the search device 1 displays the identification information of the relay device 3A included in the first received notification signal on the screen of the display unit 12 (see FIG. 17A).

  In addition, in the sixth period 413 (for example, 2 ms) immediately after receiving the notification signal in the fifth period 412, the search device 1 transmits a search instruction signal to the relay device 3A that is the transmission source of the notification signal. The search instruction signal includes identification information of the own device, identification information of the relay device 3A to be communicated, identification information of the search target device 2 to be searched, and timing information for instructing transmission timing of a search result signal (described later). included. Then, the search device 1 performs reception processing in the seventh period 414-1 (for example, 5 ms) including the transmission timing of the search result signal.

  When the relay device 3A receives the search instruction signal from the search device 1, the relay device 3A repeatedly transmits the calling signal in the individual search mode in the eighth period 433 (for example, 3.5 s) longer than the first interval. The call signal includes the identification information of the own device, the identification information of the search target device 2 to be searched, and timing information indicating the transmission timing of the response confirmation signal. The relay device 3A performs reception processing in the ninth period 434-1 (for example, 5 ms) including the transmission timing of the response confirmation signal.

  When the searched device 2 receives the call signal from the relay device 3A during the second period 421-3, the searched device 2 individually receives the call signal in the tenth period 422-1 (for example, 2 ms) specified by the timing information included in the call signal. A paging 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 at the radio frequency of the channel.

  The relay device 3A, in the 11th period 435-1 (for example, 2 ms) immediately after receiving the call response signal, the response confirmation signal including the identification information of the own device and the identification information of the searched device 2 at the radio frequency of the dedicated channel. Send.

  The searched device 2 performs a reception process in a twelfth period 423-1 (for example, 3 ms) immediately after the tenth period 422-1. And the to-be-searched apparatus 2 will transmit a response signal again in the 10th period 422-2 after the 2nd space | interval (for example, 100 ms) passes, if a response confirmation signal is received.

  After receiving the call response signal, the relay device 3A searches for a search result signal indicating that the searched device 2 has been found in the thirteenth period 436-1 (for example, 2 ms) indicated by the timing information included in the search instruction signal. Send. This search result signal includes identification information of the own device, identification information of the search target device 2 to be searched, information indicating that the search target device 2 has been found, and information indicating the distance of the search target device 2. .

  Search device 1 includes its own identification information and identification information of relay device 3A at the radio frequency of the dedicated channel in the fourteenth period 415-1 (for example, 2 ms) immediately after receiving the search result signal from relay device 3A. Send a result confirmation signal. Further, the search device 1 displays the identification information of the search target device 2, information indicating that the search target device 2 has been found, and the distance to the search target device 2 (see FIG. 17B).

  The relay device 3A performs reception processing in a fifteenth period 437-1 (for example, 3 ms) immediately after the thirteenth period 436-1. And the relay apparatus 3 will transmit a search result signal again in the 13th period 436-2 after 2nd space | interval (for example, 100 ms) passes, if a result confirmation signal is received.

  Thereafter, until a disconnection instruction is received from the user, search device 1 and relay device 3A repeat transmission / reception of the search result signal and transmission / reception of the result confirmation signal, and relay device 3A and search target device 2 transmit the response signal. Repeat transmission / reception and transmission / reception of response confirmation signal.

  The search device 1 transmits a disconnection signal when there is a disconnection instruction from the user. When the relay device 3A receives the disconnection signal, the relay device 3A performs a disconnection process with the searched device 2. Search device 1, searched device 2, and relay device 3A return to the standby state when the disconnection process is completed.

  When the relay device 3A does not receive the call response signal, the relay device 3A transmits a search result signal indicating that the searchee device 2 has not been found, and returns to the standby state. The search result signal includes identification information of the own device, identification information of the search target device 2 to be searched, and information indicating that the search target device 2 was not found. In this case, the search device 1 transmits a search instruction signal toward the relay device 3B.

[Communication sequence in full search (group search) mode]
Next, communication in full 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 search device 1, searched device 2, and relay device 3 in the standby state are the same in all communication modes and have already been described with reference to FIG. 15, the description thereof is omitted here.

  In FIG. 16, it is assumed that there are three search target devices 2 (2-1, 2-2, 2-3) in a range where the radio waves of the relay device 3 reach.

  When the search device 1 receives the notification signal from the relay device 3 within the fifth period 412, the search device 1 displays the identification information of the relay device 3 included in the notification signal on the screen of the display unit 12 (see FIG. 17A). ), In a sixth period 413 (for example, 2 ms) immediately after receiving the notification signal, the search instruction signal is transmitted to the relay device 3. The search instruction signal indicates the identification information of the own device, the identification information of the relay device 3 to be communicated, the information requesting transmission of the identification information to all the searched devices 2, and the transmission timing of the search result signal Timing information to be included. Then, the search device 1 performs reception processing in the seventh period 414-1 (for example, 5 ms) including the transmission timing of the search result signal.

  When the relay apparatus 3 receives the search instruction signal from the search apparatus 1, the relay apparatus 3 repeatedly transmits the call signal in an eighth period 433 (for example, 3.5 s) longer than the first interval. The call signal includes identification information of the own device, information requesting transmission of identification information to all the searchee devices 2, and timing information indicating the transmission timing of the response confirmation signal. And the relay apparatus 3 performs a reception process in the 9th period 434 (for example, 3.5 s) longer than the said 1st space | interval.

  When each searched device 2 receives the paging signal from the relay device 3 during the second period 421, the wireless communication of the dedicated channel is performed in the tenth period 422 (for example, 2 ms) specified by the timing information included in the paging signal. At the frequency, a call 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, and the standby state is returned.

  After receiving the call response signal, the relay device 3 transmits a search result signal indicating that the searched device 2 is found in the thirteenth period 436 (for example, 5 ms) indicated by the timing information included in the search instruction signal. To do. This search result signal includes identification information of the own device, identification information of each searched device 2 that has been found, and information indicating that the searched device 2 has been found.

  In the fourteenth period 415 (for example, 2 ms) immediately after receiving the search result signal from the relay device 3, the search device 1 confirms the result including its own identification information and the identification information of the relay device 3 at the radio frequency of the individual channel. Send signal and return to standby. Further, the search device 1 displays identification information of each search target device 2 and information indicating that the search target device 2 has been found (see FIG. 17C).

  The relay device 3 performs reception processing in a fifteenth period 437 (for example, 3 ms) immediately after the thirteenth period 436. And the relay apparatus 3 will return to a standby state, if a result confirmation signal is received.

[Display screen]
Next, information displayed on the screen of search device 1 according to the present embodiment will be described using FIG.

  FIG. 17A is a screen when a notification signal is received from the relay device 3. On this screen, the identification information 1501 of the relay device 3 is displayed on the screen.

  FIG. 17B is a screen when the individual search mode is executed and the search result signal is received from the relay device 3 that has received the response signal from the searchee device 2. On this screen, the identification information 1502-1 of the relay device 3 that discovered the searched device 2, the identification information 1502-2 of the searched device 2, information 1502-3 regarding the distance from the relay device 3 to the searched device 2, etc. Is displayed on the screen.

  FIG. 17C is a screen when the search result signal is received from the relay device 3 that has executed the full search mode or the group search mode and has received the paging response signal from the searched device 2. On this screen, the identification information 1503-1 of the relay device 3 that has found the searched device 2 and the identification information 1503-2 of all the searched devices 2 are displayed on the screen. At this time, the identification information 1503-2 of the search target device 2 is displayed from the top in the descending order of the received signal strength in the relay device 3.

[effect]
As described above, according to the present embodiment, the relay device 3 can search the searched device 2 and inform the search device 1 (user) of the search result. Accordingly, the user can know the position of the search target device 2 even when the search target device 2 does not exist in an area where the search target device 2 can communicate with the search device 1. And by arrange | positioning the relay apparatus 3 in a high place, the communicable distance with the to-be-searched apparatus 2 can be lengthened, and a searchable area | region can be expanded. Moreover, after discovering the to-be-searched device 2 by the relay device 3, the time until the search target person is found can be further shortened by narrowing the search target area.

(Variation 1)
As variation 1 of the present embodiment, as shown in FIG. 18, the antenna 101 of the relay device 3 is an array antenna, and the relay device 3 estimates the direction of the searched device 2 from the received signal strength of radio waves in each directivity. The case where it does is demonstrated. FIG. 18A shows an array antenna in which four (2 × 2) antenna elements 101a, 101b, 101c, and 101d are arranged on the circumference at intervals of λ / 4. This array antenna can obtain directivity in four directions by switching the switches SW1 and SW2.

  Specifically, as shown in FIG. 18B, when SW1 is connected to the “0” terminal and SW2 is connected to the “0” terminal, the directivity is in the direction of 0 °. When SW1 is connected to the “1” terminal and SW2 is connected to the “0” terminal, the directivity is 90 °. When SW1 is connected to the “0” terminal and SW2 is connected to the “1” terminal, the directivity is 180 °. When SW1 is connected to the “1” terminal and SW2 is connected to the “1” terminal, the directivity is 270 °.

  In FIG. 18C, when the received signal strength of the radio wave in each directivity is a vector amount indicated by an arrow, the direction θ of the searched device 2 with respect to the relay device 3 is estimated to be about 60 °.

  Alternatively, the antenna 101 of the relay device 3 may be a sector antenna, and the relay device 3 may estimate the direction of the searched device 2 from the received signal strength of the radio wave at each antenna element. A sector antenna is one in which a plurality of antenna elements having directivity are arranged so as to cover all 360 ° directions on a horizontal plane.

  In this variation, the search device 1 can quickly narrow down the position of the searched device 2 by displaying information on the direction of the searched device 2 received from the relay device 3 on the screen. It is possible to further shorten the time to do.

(Variation 2)
As a variation 2 of the present embodiment, a case will be described in which a search instruction signal is transmitted from the searched device 2 to the relay device 3 assuming that the user of the searched device 2 seeks rescue.

[Additional structure and additional function of searched device 2]
In this case, an emergency button 25 is added as shown in FIG. Further, the following functions are added to the signal generation unit 231a and the signal acquisition unit 231b of the CPU 231.

  After the emergency button 25 is pressed, the signal generation unit 231a generates a digital signal (search instruction signal) including its own identification information and the identification information of the relay device 3, and receives the search result signal from the relay device 3. After that, a digital signal (result confirmation signal) including the identification information of the own device and the identification information of the relay device 3 is generated.

  The signal acquisition unit 231b acquires the identification information of the relay device 3 included in the notification signal from the relay device 3. 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 acquiring information indicating that the search device 1 has been found from the search result signal from the relay device 3.

[Communication sequence]
Next, the state of communication of search device 1, search target device 2, and relay device 3 according to this variation will be described with reference to the sequence diagram of FIG. The relay device 3 stores the identification information of the search device 1 in advance.

  Since the states of search device 1, searched device 2, and relay device 3 in the standby state are the same as those described using FIG. 15, the description thereof is omitted here.

  When the user of the searchee device 2 presses the emergency button 25 in the standby state, the searchee device 2 notifies the notification signal from the relay device 3 in the fifth period 412 (for example, 3.5 s) longer than the first interval. In a sixth period 413 (for example, 2 ms) immediately after receiving the notification signal, the search instruction signal is transmitted to the relay device 3. This search instruction signal includes the identification information of the own device, the identification information of the relay device 3 to be communicated, and timing information for instructing the transmission timing of the search result signal (described later). And the to-be-searched apparatus 2 performs a reception process in the 7th period 414-1 (for example, 5 ms) including the transmission timing of a search result signal. In addition, when the search target device 2 cannot receive the notification signal from the relay device 3 in the fifth period 412, after a predetermined period (for example, 300 s) has elapsed, the searched device 2 again from the relay device 3 in the fifth period 412. The broadcast signal is received.

  When receiving the search instruction signal from the searchee device 2, the relay device 3 repeatedly transmits the calling signal in an eighth period 433 (for example, 3.5 s) longer than the first interval. This call signal indicates the identification information of the own device, the identification information of the search device 1, the identification information of the search target device 2, information indicating that the search target device 2 has been found, and the transmission timing of the response confirmation signal. Timing information is included. And the relay apparatus 3 performs a reception process in the 9th period 434-1 (for example, 5 ms) including the transmission timing of a response confirmation signal.

  When the search device 1 receives the call signal from the relay device 3 during the second period 421-3, in the tenth period 422-1 (for example, 2 ms) specified by the timing information included in the call signal, the search device 1 The call response signal including the identification information of the own device and the identification information of the relay apparatus 3 of the communication partner is transmitted at the radio frequency. Further, the search device 1 displays the identification information of the search target device 2, information indicating that the search target device 2 has been found, and the distance to the search target device 2 (see FIG. 17B).

  In the eleventh period 435-1 (for example, 2 ms) immediately after receiving the paging response signal in the ninth period 434-1, the relay device 3 uses the individual channel radio frequency and the identification information of the search device 1 in the eleventh period 435-1. A response confirmation signal including the information and the identification information of the searched device 2 is transmitted.

  The search device 1 performs reception processing in the twelfth period 423-1 (for example, 3 ms) immediately after the tenth period 422-1. And the search apparatus 1 will transmit a response signal again in the 10th period 422-2 after the 2nd space | interval (for example, 100 ms) passes, if a response confirmation signal is received.

  After receiving the call response signal, the relay device 3 has received a search result signal indicating that the search device 1 has been found in the thirteenth period 436-1 (for example, 2 ms) indicated by the timing information included in the search instruction signal. Send. This search result signal includes the identification information of the own device, the identification information of the search target device 2, and information indicating that the search device 1 has been found.

  In the 14th period 415-1 (for example, 2 ms) immediately after receiving the search result signal from the relay device 3, the searched device 2 receives the identification information of the own device and the identification information of the relay device 3 at the radio frequency of the individual channel. A result confirmation signal is transmitted. Further, when the searchee device 2 learns from the search result signal that the search device 1 has been found, the searchee device 2 causes the LED 22 to emit light and causes the ringing unit 204 to output a notification sound.

  The relay device 3 performs reception processing in the fifteenth period 437-1 (for example, 3 ms) immediately after the thirteenth period 436-1. And the relay apparatus 3 will transmit a search result signal again in the 13th period 436-2 after 2nd space | interval (for example, 100 ms) passes, if a result confirmation signal is received.

  Thereafter, until the user of search device 1 receives a disconnect instruction, searched device 2 and relay device 3 repeat transmission / reception of the search result signal and transmission / reception of the result confirmation signal, and relay device 3 and search device 1 The transmission / reception of response signals and the transmission / reception of response confirmation signals are repeated.

(Variation 3)
As a variation 3 of the present embodiment, a case will be described in which when the search target device 2 is searched using a plurality of relay devices 3, the arrangement height of the relay devices 3 is varied.

  FIG. 21 shows an example in which the searchee device 2 is searched by formation of one search device 1 and four relay devices 3A, 3B, 3C, and 3D. In FIG. 21, the relay device 3 </ b> A is installed at a position where the height h from the ground at a point where the search device 1 exists, such as the top of a mountain, is 200 m. The relay devices 3B, 3C, and 3D are installed at a height h of 30 to 40 m, for example, on the rooftop of a building. The communicable area E3A of the relay device 3A includes the communicable areas E3B, E3C, and E3D of the relay devices 3B, 3C, and 3D. The distance between the relay device 3A and the relay device 3C is shorter than the distance between the relay device 3A and the relay device 3B and the distance between the relay device 3A and the relay device 3D. Search device 1 exists in region E3A and region E3B, and search target device 2 exists in region E3A and region E3D.

  In the state of FIG. 21, when the search apparatus 1 is instructed by the user to identify the search target apparatus 2 to be searched, the search apparatus 1 receives notification signals from the relay apparatuses 3A and 3B, and sends the notification signals to the relay apparatuses 3A and 3B. A search for the searchee device 2 is instructed.

  Since the searched device 2 exists in the area E3A, the relay device 3A can find the searched device 2. On the other hand, since the searched device 2 does not exist in the area E3B, the relay device 3B cannot find the searched device 2.

  Accordingly, the screen of the search device 1 displays that the relay device 3A has found the search target device 2 and the distance d3A between the relay device 3A and the search target device 2 (see FIG. 17B). Thereby, the user of the search device 1 can know that the search target device 2 does not exist in the area E3B. Further, the user of the search device 1 can know from the distance d3A that the search target device 2 does not exist in the area E3C but exists in the area E3D.

  Therefore, the user of the search device 1 moves with the search device 1 in the region E3D, and searches the search target device 2 using the region E3D as a search target region.

  As described above, the search target device 2 can be quickly searched by searching for the search target device 2 using a plurality of relay devices 3 having different arrangement heights (communication areas). Time to discover a person can be further shortened.

(Variation 4)
As a variation 4 of the present embodiment, the search device 1 is carried to a high place, the search device 1 alone is searched for the search target device 2, and the search target device 2 is searched using a plurality of relay devices 3. explain.

  FIG. 22 shows an example in which the search device 1 is moved to the position of the relay device 3A in FIG. 21 and the search target device 2 is searched by formation of one search device 1 and three relay devices 3B, 3C, and 3D. ing. The communicable area E1 of the search device 1 includes the communicable areas E3B, E3C, E3D of the relay apparatuses 3B, 3C, 3D. The searched device 2 exists in the area E1 and the area E3D.

  In the state shown in FIG. 22, when the search apparatus 1 is instructed by the user to identify the search target apparatus 2 to be searched, the search apparatus 1 starts searching for the search target apparatus 2. In addition, the search device 1 receives notification signals from the relay devices 3B, 3C, and 3D, and instructs the relay devices 3B, 3C, and 3D to search for the searched device 2.

  Since the searched device 2 exists in the area E1, the searching device 1 can find the searched device 2. Therefore, on the screen of the search device 1, the fact that the search target device 2 has been found and the distance d1 between the search device 1 and the search target device 2 are displayed (see FIG. 8E).

  In addition, since the searched device 2 exists in the area E3D, the relay device 3D can find the searched device 2. On the other hand, since the searched device 2 does not exist in the areas E3B and E3C, the relay devices 3B and 3C cannot find the searched device 2. Accordingly, the screen of the search device 1 displays that the relay device 3D has found the search target device 2 and the distance d3D between the relay device 3D and the search target device 2 (see FIG. 17B).

  Thereby, the user of the search device 1 can know that the search target device 2 exists in the area E3D. Further, the user of the search device 1 can know the partial region (direction from the relay device 3D) where the search target device 2 exists in the region E3D by the distance d1 and the distance d3D.

  Therefore, the user of the search apparatus 1 moves with the search apparatus 1 in the area E3D, and searches the search target apparatus 2 using the partial area of the area E3D as a search target area.

  In this way, the search apparatus 1 is carried to a high place, the search apparatus 1 alone is searched for the search target apparatus 2, and the search apparatus 2 is searched using a plurality of relay apparatuses 3. As a result, the time until the search target person is found can be further shortened.

(Variation 5)
Variation 5 of the present embodiment is a combination of variations 3 and 4. The relay device 3A in which the search device 1 is located at a high place is searched for by the relay device 3A alone and other relays. A case where a search using devices 3B, 3C, and 3D is instructed will be described.

  In FIG. 23, the positions of the search device 1, the searched device 2, and the relay devices 3A, 3B, 3C, and 3D are the same as the example shown in FIG.

  In the state shown in FIG. 23, when the search apparatus 1 is instructed by the user to identify the search target apparatus 2 to be searched, the search apparatus 1 instructs the relay apparatus 3A to search for the search target apparatus 2. The relay device 3A starts searching for the searched device 2 independently. Further, the relay device 3A receives the notification signals from the relay devices 3B, 3C, and 3D, and instructs the relay devices 3B, 3C, and 3D to search for the searched device 2.

  Since the searched device 2 exists in the area E3A, the relay device 3A can find the searched device 2. Accordingly, the screen of the search device 1 displays that the relay device 3A has found the search target device 2, and the distance d3A between the relay device 3A and the search target device 2.

  In addition, since the searched device 2 exists in the area E3D, the relay device 3D can find the searched device 2. On the other hand, since the searched device 2 does not exist in the areas E3B and E3C, the relay devices 3B and 3C cannot find the searched device 2. Accordingly, the screen of the search device 1 displays that the relay device 3D has found the search target device 2 and the distance d3D between the relay device 3D and the search target device 2.

  Thereby, the user of the search device 1 can know that the search target device 2 exists in the area E3D. Further, the user of the search device 1 can know the partial region (direction from the relay device 3D) where the search target device 2 exists in the region E3D by the distance d3A and the distance d3D.

  Therefore, the user of the search apparatus 1 moves with the search apparatus 1 in the area E3D, and searches the search target apparatus 2 using the partial area of the area E3D as a search target area.

  In this way, the search apparatus 1 is carried to a high place, the search apparatus 1 alone is searched for the search target apparatus 2, and the search apparatus 2 is searched using a plurality of relay apparatuses 3. As a result, the time until the search target person is found can be further shortened.

  The present invention is suitable for use in a search device, a relay device, and a communication system for searching for a search target device.

DESCRIPTION OF SYMBOLS 1 Search apparatus 2 Searched apparatus 3 Relay 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)
121, 221 Transmitter 122, 222 Receiver 123, 223 Radio controller 124, 224 First clock 125, 225 First switch 131, 231, 331 CPU
131a, 231a, 331a Signal generation unit 131b, 231b, 331b Signal acquisition unit 131c, 331c Distance estimation unit 132, 232 Memory unit 133, 233 Second clock 134, 234 Third clock 135 Logic operation unit

Claims (6)

A portable search device that performs wireless communication directly with a portable search target device and performs wireless communication with a relay device that performs wireless communication with the search target device.
A transmission unit that transmits a search instruction signal including identification information of the searched device and identification information of the relay device to the relay device;
A receiving unit that receives a search result signal including information indicating a search result of the searched device from the relay device;
A display unit for displaying information indicating a search result of the search target device;
A search device comprising: The receiving unit receives a notification signal including identification information of the relay device from the relay device;
The transmission unit transmits the search instruction signal to the relay device after receiving the notification signal.
The search device according to claim 1. A relay device that performs wireless communication with a portable search device and performs wireless communication with a portable search target device that performs wireless communication with the search device,
A receiving unit that receives, from the search device, a search instruction signal including identification information of the searched device and identification information of the relay device;
After receiving the search instruction signal, a transmission unit that transmits a calling signal including identification information of the searched device to the searched device;
Comprising
The receiving unit receives a response signal corresponding to the calling signal from the searched device;
A control unit that generates information indicating a search result of the search target device based on whether the response signal has been received;
The transmitter transmits a search result signal including information indicating a search result of the search target device to the search device;
Relay device. The control unit estimates a distance from the search target device;
When the transmission unit is able to receive the response signal, the transmission unit transmits the search result signal including information indicating a distance from the searched device to the searching device.
The relay device according to claim 3. A communication system comprising: a portable search device; a portable search device; and the search device and a relay device that performs wireless communication with the search target device. A search method for a search device, comprising:
The search device transmits a search instruction signal including identification information of the searched device and identification information of the relay device to the relay device;
After the relay device receives the search instruction signal, the relay device transmits a paging signal including identification information of the searched device to the searched device,
When the relay device receives a response signal corresponding to the call signal from the searched device, the relay device transmits a signal indicating a search result of the searched device to the searching device.
Search method. The relay device is arranged at a position higher than the search device,
The search method according to claim 5.

Images