JP6847782B2 - Distance judgment system and distance judgment method - Google Patents

Description

The present invention relates to a distance determination system and a distance determination method for determining a distance from a distance determination device to a transmission device.

BLE (Bluetooth (registered trademark) Low Energy) is known as one of the short-range wireless communication technologies. BLE is a technology developed with the intention of performing Bluetooth communication with low power consumption. Further, there is known a technique called RSSI (Received Signal Strength Indication) in BLE for determining a distance using radio wave strength. In this technique, the distance determination device receives radio waves transmitted from the BLE tag of the Bluetooth device at an arbitrary location. The BLE tag has an arbitrary UUID (Universally Unique Identifier) identifier. Then, the distance determination device is a distance from the distance determination device to the Bluetooth device having the tag identified by the UUID (hereinafter, “identifier”) based on the RSSI (hereinafter, “radio wave intensity”). To judge.

For example, in Non-Patent Document 1, the position of a communication device is determined by using the relationship between the distance between communication devices that perform short-range wireless communication using radio waves and the radio wave intensity of the radio waves received by the communication device. Is disclosed.

Further, Non-Patent Document 2 describes that the moving direction and the moving distance of the communication device are determined based on the change in the radio wave intensity of BLE.

Further, Non-Patent Document 3 describes that the position of the communication device is determined by using the fingerprint method.

Further, in Non-Patent Document 4, the position of the terminal is determined based on the RSSI value in the communication between the base and the communication device installed in the area where the position is determined and the characteristics of the measurement environment learned in advance. Is described.

Further, Non-Patent Document 5 describes that a smartphone compatible with BLE downloads an application for detecting a BLE radio wave, and uses the application to acquire an identifier and a radio wave intensity of a radio wave transmitted from a transmitter. ing. Thereby, the distance between the smartphone and the communication device having the tag can be determined by one smartphone corresponding to BLE without using a plurality of detection devices.

Tomomi Sato, 5 outsiders, "Examination of position estimation method using Bluetooth signal strength", DEIM Forum (Forum on data engineering and information management), B9-4, 2011 Miyoshi Horikawa, 3 outsiders, "Proposal of hybrid indoor positioning method using BLE positioning and PDR", IPSJ Research Report, Vol.2015-MBL-76 No.13, Vol.2015-CDS-14 No.13, October 2, 2015 Ramsey Faragher, 1 outside, "Location Fingerprinting With Bluetooth Low Energy Beacons", IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL.33, NO.11, November 2015 Tomotaka Tsujino, 3 outsiders, "Learning-based position coordinate estimation system and its application", The 23rd Annual Conference of the Japanese Society for Artificial Intelligence, 2009 ASCII.jp, "If you have two iPhones / iPads, you can experience iBeacon", December 26, 2012, [Search June 1, 2017], Internet <URL: http: // ascii .jp / elem / 000/000/964/964201/>

As described above, there is known a technique of acquiring the radio wave strength of a "radio wave indicating an identifier of a communication device" and determining the distance from the reception location of the radio wave to the communication device based on the radio wave strength. For example, a smartphone, a wearable device, or the like that supports the BLE standard and the WiFi (registered trademark) standard emits a radio wave indicating an identifier. In this case, the device receiving the radio wave determines the distance to the smartphone, wearable device, etc. identified by the identifier indicated by the radio wave based on the strength of the radio wave.

By using such a technology, a plurality of detectors capable of detecting a communication device and measuring a distance are arranged, and the distance to a communication device having an arbitrary identifier obtained from the plurality of detectors can be fingerprinted or three. It is possible to construct a system for locating the communication device using edge measurement. For example, parents may use the system to locate their children. The parent allows the child to possess the communication device, and the parent can access the system to locate the communication device possessed by the child.

However, it is possible to easily measure the distance between the detector and the communication device without using the system that identifies the location of such a communication device. For example, a BLE-compatible smartphone can measure the distance to a communication device that emits radio waves in accordance with the BLE standard. Therefore, the location of the target person who owns the communication device is determined by the distance between the detector owned by the third party and the communication device owned by the target person and the visual confirmation of the target person by the third party. It is also possible to identify. When a third party recognizes the distance of the target person from the communication device, there is a possibility that the target person who has the communication device may commit a crime such as kidnapping or stalking, or infringe on privacy. In addition, a malicious third party may recognize whether or not a resident with a communication device is at home in a nearby residence. In addition, even if the subject who has the communication device escapes from the stalker or disguises because the stalker does not visually recognize it, the radio waves transmitted by the communication device possessed by the subject can be transmitted from a third party to the subject. The distance may be known.

An object of the present invention made in view of such circumstances is to provide a distance determination system and a distance determination method capable of preventing the distance to a communication device from being determined by a device owned by a third party.

In order to solve the above problems, the distance determination system according to the present invention is a distance determination system including a transmission device and a distance determination device that perform wireless communication at a short distance from each other, and the transmission device uses the transmission device. A transmission data creation unit that creates a first transmission data including a transmitter identifier for identification, and a transmission data creation unit that is changed based on a predetermined rule, and the change rule is for identifying a power strength known in the distance determination device. A control unit that creates a second transmission data in which a transmission power identifier is added to the first transmission data, and a transmission unit that transmits a first message including the second transmission data with the power of the power intensity are provided. distance determination device receives the first message from said transmitter, a receiver for acquiring a radio wave intensity of the radio wave indicating the first message, corresponding to the transmission power identifier included in said first message, said an adjusting unit that calculates the radio intensity correction value by correcting the radio field intensity based on the radio wave intensity correction coefficient that will be set based on a predetermined rule, based on the radio wave intensity correction value, the originating from the distance determining device It is characterized by including a distance determination unit that determines the distance to the device, a display unit that displays the distance determined by the distance determination unit, and the transmitter identifier included in the second transmission data. To do.

Further, the distance determination system according to the present invention includes a transmission device, a plurality of distance determination devices that perform short-range wireless communication with the transmission device, and a position determination device that receives information from the distance determination device. In the system, the transmission device is modified based on a predetermined rule with a transmission data creation unit that creates a first transmission data including a transmission device identifier for identifying the transmission device, and the change rule is changed. comprising a second control unit that generates transmission data transmission power identifier for identifying a known power strength was added to the first transmission data in the distance determination device, the second transmission data in power of the power intensity A transmission unit that transmits a first message to the plurality of distance determination devices is provided, and each of the plurality of distance determination devices receives the first message from the transmission unit of the transmission device, and a radio wave indicating the message. radio waves and receiving unit the radio wave intensity is obtained by the response to the transmission power identifier included in the first message, to correct the radio field intensity based on the radio wave intensity correction coefficient that will be set based on the predetermined rule An adjustment unit that calculates an intensity correction value, a distance determination unit that determines the distance from the distance determination device to the transmission device based on the radio wave intensity correction value, position information indicating the position of the own device, and the distance. The position determination device includes a transmission unit that transmits a second message including distance information indicating the above to the position determination device, and the position determination device includes the second message and the radio wave intensity from the transmission unit of each of the plurality of distance determination devices. A receiving unit that receives information, a position determining unit that determines the position of the transmitting device based on the own position information and the distance information included in each of the plurality of second messages, and a position determining unit that determines the position. It is characterized by including a position information indicating the position of the transmitting device and a transmitting unit that transmits the transmitting device identifier included in the second message to the display device.

Further, the distance determination method according to the present invention is a distance determination method executed by a transmission device and a distance determination device that perform wireless communication at a short distance from each other, and the transmission device transmits a transmission for identifying the transmission device. The first transmission includes a step of creating a first transmission data including a device identifier, and a transmission power identifier that is modified based on a predetermined rule and the change rule identifies a known power strength in the distance determination device. The distance determination device includes the step of creating the second transmission data added to the data and the step of transmitting the first message including the second transmission data with the power of the power intensity, and the distance determination device is said to be said from the transmission device. receiving a first message, said acquiring a field intensity of radio waves indicating a first message, the response to the transmission power identifier included in the first message, based on the predetermined rule set Ru radio intensity correction A step of calculating a radio field intensity correction value by correcting the radio wave intensity based on a coefficient, a step of determining a distance from the distance determining device to the transmitting device based on the radio wave intensity correction value, and the distance. It is characterized by including a step of displaying the transmitter identifier included in the second transmission data and a step of displaying the transmitter identifier.

An object of the present invention is to prevent a device owned by a third party from determining the distance to a communication device.

It is a figure which shows the structural example of the distance determination system which concerns on 1st Embodiment. It is a figure which shows the example of the transmission setting information set by the transmission setting part shown in FIG. It is a figure which shows the structure of the 1st transmission data, the 2nd transmission data, and the 1st telegram. It is a figure which shows the example of the reception setting information set by the reception setting part shown in FIG. It is a figure which shows the whole structure image of 1st Embodiment, and the display example of each of a distance determination apparatus and other apparatus. It is a sequence diagram which shows an example of the preparation process of the distance determination method which concerns on 1st Embodiment. It is a sequence diagram which shows an example of the display process of the distance determination method which concerns on 1st Embodiment. It is a flow chart which shows the detail of the process based on the transmission setting information shown in FIG. 7. It is a flow chart which shows the detail of the process based on the reception setting information shown in FIG. 7. It is a figure which shows the structural example of the distance determination system which concerns on 2nd Embodiment. It is a figure which shows the structure of the 3rd transmission data and the 2nd telegram. It is a figure which shows the whole structure image of 2nd Embodiment, and the display example of the position determination apparatus. It is a figure which shows the other structural example of the distance determination system which concerns on 1st Embodiment. It is a figure which shows the other structural example of the distance determination system which concerns on 2nd Embodiment.

[First Embodiment]
Hereinafter, the first embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a configuration example of the distance determination system 1 according to the first embodiment. As shown in FIG. 1, the distance determination system 1 includes a transmission device 10 and a distance determination device 20. The transmitting device 10 and the distance determining device 20 can perform wireless communication at a short distance from each other. The short-range wireless communication standard may include, for example, a BLE standard and a WiFi standard.

<Transfer device>
The transmitting device 10 transmits a first telegram including arbitrary data by short-range wireless communication. The transmission device 10 includes a transmission setting unit 11, a transmission data creation unit 12, a control unit 13, and a transmission unit 14.

The transmission setting unit 11 sets the transmission device identifier, the transmission interval information, and the transmission setting information. The transmitting device identifier is an identifier for uniquely identifying the transmitting device 10. The transmission interval information is information indicating a time interval in which the transmission data creation unit 12 creates the first transmission data, and is also information indicating a time interval in which the transmission unit 14 transmits the first telegram.

The transmission setting information includes a transmission power identifier, the number of times or time that the transmission power identifier is continuously added to the first transmission data described later, the order in which the transmission power identifier is added, and the power strength corresponding to the transmission power identifier. Includes multiple combinations of.

Specifically, as shown in FIG. 2, the transmission setting information includes a plurality of combinations of the item number, the transmission power identifier, the number of standbys, and the procedure information. The item number is a number that identifies each combination included in the transmission setting information. The transmission power identifier is a name that identifies the number of standbys and procedure information corresponding to each item number. The number of standbys is the number of times that the control unit 13 continuously adds the same transmission power identifier to the first transmission data. The standby time is a time during which the control unit 13 continuously adds the same transmission power identifier to the first transmission data. The procedural information includes power strength and order. The power intensity indicates the intensity of the transmission power used when the transmission unit 14 transmits data. The order indicates the order of the transmission power identifiers used by the transmission data creation unit 12 and the control unit 13 for processing.

When the transmission device 10 is activated, the transmission data creation unit 12 acquires the transmission device identifier and transmission interval information from the transmission setting unit 11 and stores them in the memory. Further, the transmission data creation unit 12 creates the first transmission data at the time interval indicated by the transmission interval information. As shown in FIG. 3A, the first transmission data is data including, for example, a transmitter identifier and arbitrary data. When the transmission data creation unit 12 creates the first transmission data, the transmission data creation unit 12 outputs the first transmission data to the control unit 13.

When the transmission device 10 is activated, the control unit 13 acquires transmission setting information from the transmission setting unit 11 and stores it in the memory. Specifically, the control unit 13 stores each item number of the transmission setting information, the transmission power identifier corresponding to each item number, the number of standby times, and the procedure information in the memory.

Further, the control unit 13 stores the constant n as the number of combinations (number of lines) in the transmission setting information. The control unit 13 sets the first variable k corresponding to each item number of the transmission setting information as an initial value (for example, “1”) and stores it in the memory. The control unit 13 stores the second variable s corresponding to the number of waits of the transmission setting information in the memory as the number of waits corresponding to the item number indicated by the first variable k. In the example shown in FIG. 2, the control unit 13 sets the first variable k to the initial value “1” and sets the second variable s to the number of waits “1200” corresponding to the item number “1”.

Further, the control unit 13 receives the first transmission data output from the transmission data creation unit 12. When the control unit 13 receives the first transmission data, the control unit 13 performs a predetermined process based on a predetermined rule indicated by the transmission setting information. In the predetermined process, as shown in FIG. 3B, the second transmission data in which any one of the plurality of transmission power identifiers stored in the transmission setting information is added to the first transmission data is created and transmitted. The process of outputting to unit 14 is included. The predetermined process includes a process of outputting the power intensity information indicating the power intensity corresponding to the transmission power identifier added to the first transmission data to the transmission unit 14.

Here, a process in which the control unit 13 generates the second transmission data based on a predetermined rule will be described in detail.

The control unit 13 creates the second transmission data in which the transmission power identifier is added to the first transmission data based on the number of standbys or the standby time included in the transmission setting information and the order. Explaining with reference to the example shown in FIG. 2, the control unit 13 sets the first variable k as the initial value “1” and the second variable s as “1200” as described above. When the control unit 13 receives the first transmission data from the transmission data creation unit 12, the control unit 13 subtracts 1 from the second variable s stored in the memory. Then, when the second variable s is 1 or more, the control unit 13 performs processing based on the procedure information corresponding to the item number indicated by the first variable k. Specifically, 1199, which is obtained by subtracting 1 from 1200, which is the second variable s, is 1 or more. In this case, the control unit 13 creates the second transmission data by adding the transmission power identifier “abc1” of item No. 1 corresponding to the first variable k to the first transmission data. Further, the control unit 13 outputs the power intensity information indicating 100% of the power intensity to the transmission unit 14 based on the transmission procedure information of the item No. 1 corresponding to the first variable k. The power intensity when the transmission power is not changed is set to 100%.

When the control unit 13 next receives the first transmission data, the control unit 13 further subtracts 1 from the second variable s. Specifically, the control unit 13 sets 1198, which is the second variable s, which is obtained by subtracting 1 from 1199, as the new second variable s. This new second variable, 1198, is greater than or equal to 1. In this case, the control unit 13 performs the same processing as described above. In this way, the control unit 13 repeats the process every time it receives the first transmission data, and when the second variable s becomes smaller than 1, whether or not the first variable k is the same as the number of lines n of the transmission setting information. Is determined.

When it is determined that the first variable k is the same as the number of lines n of the transmission setting information, the control unit 13 sets the first variable k to 1. When it is determined that the first variable k is not the same as the number of lines n of the transmission setting information, the control unit 13 sets the value obtained by adding 1 to the first variable k as the new first variable k. In the example shown in FIG. 2, n = 4. Further, in the above example, since the first variable k is 1, it is not the same as n. Therefore, the control unit 13 sets 2 as a new first variable k by adding 1 to 1 which is the first variable k. Then, the control unit 13 sets the second variable s to 600, which is the number of times of waiting for item No. 2 corresponding to the first variable k. Then, the control unit 13 adds the transmission power identifier “def2” of item No. 2 to the first transmission data to create the second transmission data. Further, the control unit 13 outputs the generated second transmission data to the transmission unit 14. Further, the control unit 13 outputs the power intensity information indicating the power intensity of 80% to the transmission unit 14 based on the transmission procedure information of the item No. 2 corresponding to the first variable k.

The control unit 13 decrements the second variable s by 1 each time this process is repeated. Then, when the second variable s becomes smaller than 1, the control unit 13 adds 1 to the first variable k to make it 3, and sets the second variable s to the number of waits 300 corresponding to the item number 3. When the transmission data creation unit 12 creates the first transmission data at the time interval shown in the transmission interval information and the control unit 13 performs the above processing on the first transmission data, 600 in the example shown in FIG. The time for repeating the rounding process corresponds to 1 minute.

The transmission unit 14 receives the power intensity information output from the control unit 13 and the second transmission data. When the transmission unit 14 receives the second transmission data from the control unit 13, the transmission unit 14 generates a first telegram including the second transmission data. The telegram is data in which a header and a footer are added to the second transmission data as shown in FIG. 3C. When the second transmission data is generated, the transmission unit 14 transmits the first telegram with the power of the power strength indicated by the received power strength information.

<Distance judgment device>
The distance determination device 20 receives the first telegram transmitted from the transmission device 10. The distance determination device 20 determines the distance from the distance determination device 20 to the transmission device 10 based on the radio wave intensity of the radio wave indicating the first telegram. As shown in FIG. 1, the distance determination device 20 includes a reception setting unit 21, a reception unit 22, an adjustment unit 23, a distance determination unit 24, and a display unit 25.

The reception setting unit 21 is a memory for storing predetermined information. The reception setting unit 21 sets the reception setting information as shown in FIG. The reception setting information includes a plurality of combinations of the item number, the transmission power identifier, and the reception procedure information. The item number is a number that identifies each combination included in the reception setting information. The transmission power identifier is the same as the transmission power identifier included in the transmission procedure information set in the transmission device 10. The reception procedure information corresponds to the transmission procedure information. Specifically, the reception procedure information is the radio wave intensity of the radio wave received when the transmission power is changed based on the predetermined rule indicated by the transmission procedure information, and the radio wave when the transmission power is not changed. The rules for correcting to strength are shown. More specifically, the reception procedure information includes a radio field intensity correction coefficient corresponding to each transmission power identifier. The radio field strength correction coefficient is the reciprocal of the power strength corresponding to the transmission power identifier in the transmission procedure information. Thereby, the radio wave intensity correction value calculated by correcting the radio wave intensity based on the reception procedure information indicates the radio wave intensity when the transmitting device 10 receives the radio wave transmitted without changing the power.

The receiving unit 22 receives the first telegram transmitted from the transmitting device 10. The receiving unit 22 acquires the second transmission data included in the first telegram. The receiving unit 22 acquires the radio wave strength of the radio wave indicating the first telegram, and generates radio wave strength information including the radio wave strength. The receiving unit 22 outputs the second transmission data and the radio wave intensity information to the adjusting unit 23.

When the distance determination device 20 is activated, the adjustment unit 23 acquires the reception setting information set by the reception setting unit 21 and stores it in the memory. Specifically, the adjusting unit 23 stores each item number of the reception setting information, and the transmission power identifier and the procedure information corresponding to each item number in the memory.

The adjusting unit 23 receives the second transmission data output from the receiving unit 22 and the radio wave intensity information. The adjusting unit 23 corrects the radio field intensity by using the radio wave strength correction coefficient corresponding to the transmission power identifier included in the second transmission data.

Specifically, the adjusting unit 23 acquires the transmission power identifier from the second transmission data. Then, the adjusting unit 23 compares the transmission power identifier of the second transmission data with the transmission power identifier of the reception setting information, and acquires the target reception procedure information. For example, the adjusting unit 23 acquires the radio field intensity correction coefficient corresponding to the transmission power identifier included in the reception setting information, which is the same as the transmission power identifier included in the second transmission data. Then, the adjusting unit 23 corrects the radio wave intensity based on the acquired radio wave intensity correction coefficient. Explaining with reference to the example shown in FIG. 4, when the transmission power identifier of the second transmission data is “abc1”, the radio field intensity correction coefficient is 100/100, so the radio wave strength is not corrected. When the transmission power identifier included in the radio field strength information is "def2", the radio field strength correction coefficient is 100/90. In this case, the adjusting unit 23 calculates the radio field strength correction value by correcting the radio wave strength to 100/90 times. Similarly, when the transmission power identifiers of the second transmission data are "ghk3" and "hij4", the adjusting unit 23 corrects the radio field strength to 100/80 times and 100/90 times, respectively, and the radio wave strength correction value. Is calculated.

The adjusting unit 23 outputs the radio wave intensity correction information including the radio wave intensity correction value and the first transmission data included in the second transmission data to the distance determination unit 24.

The distance determination unit 24 receives the radio field intensity correction information and the first transmission data. The distance determination unit 24 determines the distance from the distance determination device 20 to the transmission device 10 based on the radio wave intensity correction value included in the radio wave intensity correction information. Any known method may be used for determining the distance. For example, the distance determination unit 24 can extract the distance stored in the memory in advance corresponding to the radio wave intensity correction value, and use the extracted distance as the distance from the distance determination device 20 to the transmission device 10.

When the BLE standard is applied as a standard for short-range communication between the transmitter 10 and the distance determination device 20, the distance determination unit 24 is included in an arbitrary field (for example, a header unit) of the first message. The distance may be determined using the value of the radio field strength field. The radio field strength field shows the relationship between the distance between two communication devices with which communication is performed and the radio field strength. Therefore, the distance determination unit 24 can determine the distance based on the radio wave intensity correction value by using the value of the radio wave intensity field indicating the reference.

The distance determination unit 24 outputs the distance information indicating the distance determined based on the radio wave intensity correction value and the transmitter identifier included in the first transmission data to the display unit 25. The distance determination unit 24 may output radio field intensity correction information to the display unit 25 instead of the distance information or in addition to the distance information.

The display unit 25 receives the transmitter identifier output from the distance determination unit 24 and the distance information. The display unit 25 displays the transmitter identifier and the distance information on the display. The display unit 25 may receive the radio field intensity correction information instead of the distance information or in addition to the distance information and display it on the display.

FIG. 5 shows an example in which the display unit 25 displays the transmitter identifier and the radio wave intensity correction information on the display. As described above, the display unit 25 included in the distance determination device 20 of the present embodiment displays the radio wave intensity correction value included in the radio wave intensity correction information by the adjustment unit 23. On the other hand, another device different from the distance determination device 20 of the present embodiment cannot correct the radio wave intensity of the radio wave received by the device and displays it as it is.

Next, the preparatory process of the distance determination method by the distance determination system 1 will be described with reference to FIG. FIG. 6 is a sequence diagram showing an example of the setting process of the distance determination method. The preparatory process is started when the transmission device 10 and the distance determination device 20 are activated, respectively.

The transmission data creation unit 12 acquires the transmission device identifier and transmission interval information from the transmission setting unit 11 and stores them in the memory (step S11).

The control unit 13 acquires the transmission setting information from the transmission setting unit 11 and stores it in the memory (step S12).

Next, the control unit 13 stores the value of the constant n as the number of lines of transmission setting information (step S13).

Next, the control unit 13 sets the first variable k as an initial value and stores it in the memory (step S14).

Next, the control unit 13 sets the second variable s as the number of waits corresponding to the item number indicated by the first variable k and stores it in the memory (step S15).

The adjusting unit 23 acquires the reception setting information set by the reception setting unit 21 and stores it in the memory (step S16).

Next, the display processing of the distance determination method by the distance determination system 1 will be described with reference to FIG. 7. FIG. 7 is a sequence diagram showing an example of display processing of the distance determination method. The preparatory process is started when the preparatory processes for the transmitting device 10 and the distance determining device 20 are completed.

Next, the transmission data creation unit 12 creates the first transmission data at the time interval indicated by the transmission interval information set in the transmission setting unit 11 (step S21).

Next, the transmission data creation unit 12 outputs the first transmission data to the control unit 13 (step S22).

The control unit 13 receives the first transmission data output from the transmission data creation unit 12 (step S23).

Next, the control unit 13 performs processing based on the transmission setting information (step S24).

Here, the process based on the transmission setting information performed by the control unit 13 will be described in detail with reference to FIG.

First, the control unit 13 subtracts 1 from the second variable s stored in the memory (step S241).

Next, the control unit 13 determines whether or not the second variable s is less than 1 (step S242).

When it is determined in step S242 that the second variable s is less than 1, the control unit 13 determines whether or not the first variable k is the same as n (step S243).

When it is determined that the first variable k is the same as n, the control unit 13 sets the first variable k to 1 (step S244).

When it is determined that the first variable k is not the same as n, the control unit 13 adds 1 to the first variable k (step S245).

Next, the control unit 13 sets the second variable s as the number of waits corresponding to the item number indicated by the first variable k and stores it in the memory (step S246).

Next, the control unit 13 adds the transmission power identifier corresponding to the item number of the first variable k to the first transmission data to create the second transmission data (step S247).

Next, the control unit 13 outputs the power strength information to the transmission unit 14 based on the procedure information corresponding to the item number of the first variable k (step S248).

Next, the control unit 13 outputs the second transmission data created in step S247 to the transmission unit 14 (step S249).

Returning to FIG. 7, the transmission unit 14 receives the power intensity information output from the control unit 13 (step S25).

The transmission unit 14 receives the second transmission data (step S26).

Next, the transmission unit 14 creates the first telegram based on the second transmission data (step S27).

Next, the transmission unit 14 transmits the first telegram with the power of the power strength indicated by the power strength information (step S28).

The receiving unit 22 of the distance determination device 20 receives the first telegram transmitted from the transmitting device 10 (step S29).

Next, the receiving unit 22 acquires the second transmission data from the first telegram, and outputs the second transmission data and the radio wave strength information indicating the radio wave strength of the radio wave indicating the first telegram to the adjusting unit 23 (step S30). ).

The adjusting unit 23 receives the second transmission data output from the receiving unit 22 and the radio wave intensity information (step S31).

Next, the adjusting unit 23 performs processing based on the reception setting information stored in the memory (step S32).

Here, the process based on the reception setting information performed by the adjusting unit 23 will be described in detail with reference to FIG.

The adjusting unit 23 acquires the transmission power identifier from the second transmission data (step S321).

Next, the adjusting unit 23 compares the transmission power identifier of the second transmission data with the transmission power identifier of the reception setting information, and acquires the target reception procedure information (step S322).

Next, the adjusting unit 23 calculates the radio wave intensity correction value by correcting the radio wave intensity indicated by the radio wave intensity information by using the radio wave intensity correction coefficient included in the reception procedure information (step S323).

Returning to FIG. 7, the adjusting unit 23 outputs the radio wave intensity correction information indicating the radio wave intensity correction value and the first transmission data included in the second transmission data to the distance determination unit 24 (step S33).

The distance determination unit 24 receives the first transmission data output from the adjustment unit 23 and the radio wave intensity information (step S34).

The distance determination unit 24 determines the distance from the distance determination device 20 to the transmission device 10 based on the radio wave intensity correction value shown in the radio wave intensity information (step S35).

Next, the distance determination unit 24 outputs the transmitter identifier and the distance information to the display unit 25 (step S36).

The display unit 25 receives the transmitter identifier and the distance information output from the distance determination unit 24 (step S37).

Next, the display unit 25 displays the transmitter identifier and the distance information on the display (step S38).

As described above, according to the first embodiment, the transmitting device 10 transmits the radio wave with the power of the power intensity identified by the transmission power identifier. The distance determination device 20 that has received the radio wave calculates the radio wave intensity correction value by correcting the radio wave intensity of the radio wave based on the transmission power identifier. Then, the distance determination device 20 determines the distance from the distance determination device 20 to the transmission device 10 based on the radio wave intensity correction value. Therefore, the distance determining device 20 can acquire the radio wave strength when the transmitting device 10 receives the radio wave transmitted without changing the power, and determines the distance to the transmitting device 10 based on the radio wave strength. can do.

On the other hand, the device owned by the third party receives the radio wave transmitted by the transmitting device 10 by changing the electric power. Therefore, the distance of the transmitter 10 determined based on the radio wave intensity of the radio wave is not accurate. In other words, even if the transmitting device 10 is stationary, the radio wave intensity of the radio wave indicating the first telegram received by the other device is changed, so that the other device is said to be operating the transmitting device 10. recognize.

Further, the transmitting device 10 transmits the second transmission data with a power having a power strength corresponding to one of the plurality of transmission power identifiers based on a predetermined rule. Therefore, even if the device owned by the third party receives the radio wave transmitted from the transmitting device 10, the radio wave strength cannot be corrected based on the transmission power identifier. Therefore, it is possible to prevent the device owned by the third party from determining the distance from the device to the transmitting device 10.

From the above, the legitimate distance determination device 20 can determine the distance from the distance determination device 20 to the transmission device 10, and the distance from the device to the transmission device 10 by a device owned by a third party can be determined. To prevent.

[Second Embodiment]
Subsequently, the second embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 10, the distance determination system 2 according to the second embodiment includes a transmission device 10, a plurality of distance determination devices 30, a position determination device 40, and a display device 50. The transmitting device 10 can communicate with each of the plurality of distance determining devices 30 by short-range wireless communication. Standards for short-range wireless communication may include, for example, the WiFi standard. The distance determination device 30 and the position determination device 40 can communicate with each other according to a short-distance or long-distance wireless communication standard or a wired communication standard. In FIG. 10, an example is shown in which the distance determination device 30 and the position determination device 40 communicate with each other according to a wired communication standard. The position determination device 40 and the display device 50 can communicate with each other according to a short-distance or long-distance wireless communication standard or a wired communication standard. FIG. 10 shows an example in which the position determination device 40 and the display device 50 communicate with each other according to a wireless communication standard. The same reference reference numerals are given to the same constituent blocks as those of the distance determination system 1 in the first embodiment, and the description thereof will be omitted as appropriate.

<Transfer device>
The transmitting device 10 in the second embodiment is the same as the transmitting device 10 in the first embodiment.

<Distance judgment device>
The plurality of distance determination devices 30 exist at different locations. The distance determination device 30 includes a reception setting unit 31, a reception unit 32, an adjustment unit 33, a distance determination unit 34, a self-position reporting unit 35, a transmission data creation unit 36, and a transmission unit 37, respectively.

The reception setting unit 31, the reception unit 32, the adjustment unit 33, and the distance determination unit 34 are the same as the reception setting unit 21, the reception unit 22, the adjustment unit 23, and the distance determination unit 24 of the first embodiment, respectively.

The self-position reporting unit 35 acquires self-position information indicating the position of the distance determination device 30. For example, the self-position reporting unit 35 may have a GPS receiver. In this case, the self-position reporting unit 35 receives information from the GPS satellite and acquires the self-position information based on the information. When the distance determination device 30 is fixedly installed, the self-position reporting unit 35 acquires the self-position information stored in advance in the memory of the distance determination device 30. In addition, the self-position reporting unit 35 outputs the acquired self-position information to the transmission data creation unit 36.

The transmission data creation unit 36 creates the third transmission data. As shown in FIG. 11A, the third transmission data includes a transmitter identifier and arbitrary data included in the first message received by the receiving unit 32, and a distance determination device identifier for identifying the distance determination device 30. , The distance information indicating the distance determined by the distance determination unit 24 and the own position information output from the own position reporting unit 35 are included. When the transmission data creation unit 36 creates the third transmission data, the transmission data creation unit 36 outputs the third transmission data to the transmission unit 37.

The transmission unit 37 receives the third transmission data output from the transmission data creation unit 36. When the transmission unit 37 receives the third transmission data from the transmission data creation unit 36, the transmission unit 37 generates a second telegram including the third transmission data. As shown in FIG. 11B, the second telegram is data in which a header and a footer are added to the third transmission data. When the transmission unit 37 generates the second telegram, the transmission unit 37 transmits the second telegram to the position determination device 40.

<Position determination device>
The position determination device 40 includes a reception unit 41, a position determination unit 42, and a transmission unit 43.

The receiving unit 22 receives the second telegram from each of the plurality of distance determination devices 30. Further, the receiving unit 22 outputs a plurality of combinations of the own position information, the distance information, the transmitting device identifier, and the distance determining device identifier included in the plurality of second telegrams to the position determining unit 42.

The position determination unit 42 receives a plurality of combinations of the own position information, the distance information, the transmission device identifier, and the distance determination device identifier output from the reception unit 22. As described above, the self-position information indicates the position of the distance determination device 30, and the distance information indicates the distance from the distance determination device 30 to the transmission device 10. Therefore, the position determination unit 42 determines the position of the transmission device 10 based on the distance from each of the plurality of distance determination devices 30 to the transmission device 10 identified by the transmission device identifier. Any known method can be used to determine the position based on each distance. Further, the position determination unit 42 outputs the position information indicating the determined position, the transmission device identifier, and the distance determination device identifier to the transmission unit 43.

The transmission unit 43 transmits the position information output from the position determination unit 42, the transmitter identifier, and the distance determination device identifier to the display device 50.

<Display device 50>
The display device 50 includes a receiving unit 51 and a display unit 52.

The receiving unit 51 receives the position information, the transmitting device identifier, and the distance determining device identifier transmitted from the position determining device 40. The receiving unit 51 outputs the received position information, the transmitting device identifier, and the distance determining device identifier to the display unit 52.

The display unit 52 receives the position information output from the reception unit 51, the transmitter identifier, and the distance determination device identifier. As shown in FIG. 12, the display unit 52 displays the received position information, the transmitter identifier, and the distance determination device identifier on the display. The display unit 52 does not have to display the distance determination device identifier on the display. In this case, the distance determination device identifier may not be included in the third transmission data and the second telegram.

As shown in FIG. 13, in the first embodiment, the transmission device 10 and the distance determination device 20 may include a first time section 15 and a second time section 26, respectively.

The first time unit 15 sets the time and the transmission power identifier correspondingly. The second time unit 26 sets the time and the transmission power identifier correspondingly.

In this case, the first time unit 15 creates a hash value calculated by combining the current time and a predetermined numerical value as a transmission power identifier. Then, the control unit 13 creates the second transmission data in which the transmitter identifier created by the first time unit 15 is added to the first transmission data. In this case, when the receiving unit 22 of the distance determination device 20 receives the first telegram transmitted from the transmitting device 10, the second time unit 26 calculates the hash value by combining the received time and a predetermined numerical value. Then, when the hash value is the same as the transmission power identifier, the adjustment unit 23 corrects the radio wave intensity with the radio wave intensity correction coefficient corresponding to the transmission power identifier.

Further, as shown in FIG. 14, in the second embodiment, the transmission device 10 and the distance determination device 20 may include a first time unit 15 and a second time unit 26, respectively. Since the first time unit 15 and the second time unit 26 in the second embodiment are the same as the first time unit 15 and the second time unit 26 in the first embodiment, the description thereof will be omitted.

As described above, according to the second embodiment, the transmitting device 10 transmits the radio wave with the power of the power intensity identified by the transmission power identifier, and the plurality of distance determination devices 30 receive the radio wave. Each of the plurality of distance determination devices 30 calculates the radio wave intensity correction value by correcting the radio wave intensity of the radio wave based on the transmission power identifier included in the first telegram transmitted from the transmission device 10. Then, each of the plurality of distance determination devices 30 determines the distance from the own device to the transmission device 10 based on the radio wave intensity correction value.

On the other hand, the device owned by the third party receives the radio wave transmitted by the transmitting device 10 by changing the electric power. Therefore, the distance of the transmitter 10 determined based on the radio wave intensity of the radio wave is not accurate. In other words, even if the transmitting device 10 is stationary, the radio wave intensity of the radio wave indicating the first telegram received by the other device is changed, so that the other device is said to be operating the transmitting device 10. recognize. Therefore, it is possible to prevent a device owned by a third party from determining the distance from the device to the transmitting device 10 based on the radio wave intensity of the radio wave, which is the same effect as in the first embodiment. ..

Secondly, according to the second embodiment, the distance determination device 20 can determine the position of the transmission device 10 based on the distance from each of the plurality of distance determination devices 30 to the transmission device 10.

In addition, a computer can be preferably used to function as the transmission device 10 described above. Such a computer can be realized by storing a program describing the processing contents that realize each function of the transmission device 10 in the database of the computer, and reading and executing this program by the CPU of the computer. it can. The same applies to the distance determination device 20.

The program may also be recorded on a computer-readable medium. It can be installed on a computer using a computer-readable medium. Here, the computer-readable medium on which the program is recorded may be a non-transient recording medium. The non-transient recording medium is not particularly limited, but may be, for example, a recording medium such as a CD-ROM or a DVD-ROM.

In the above-described embodiment, the transmission setting unit 11 may set a plurality of transmitter device identifiers. In this case, the transmission data creation unit 12 may change the transmission device identifier included in the first transmission data according to a predetermined change rule. For example, the transmission data creation unit 12 includes a transmission device identifier of one of a plurality of transmission device identifiers in the first transmission data for a predetermined time or a predetermined number of times. After that, the transmission data creation unit 12 includes the other transmission device identifier among the plurality of transmission device identifiers in the first transmission data. Then, the control unit 13 creates the second transmission data in which the transmission power identifier is added to the first transmission data as described above, and the transmission unit 14 transmits the first telegram including the second transmission data to the distance determination device 20. ..

In such an embodiment, the reception setting unit 21 sets a plurality of transmission device identifier change rules for identifying one transmission device 10. As a result, the display unit 25 displays the transmission device identifier before the change by the transmission data creation unit 12 of the transmission device 10, which is specified according to the change rule.

On the other hand, when the transmission data creation unit 12 changes the transmitter identifier included in the first transmission data by an arbitrary rule, the other devices include a plurality of transmitter identifiers different from the same transmitter 10. Receive the first telegram. At this time, the other device recognizes that a plurality of first telegrams have been received from the plurality of different transmitting devices 10. That is, other devices cannot recognize that even if the transmitting devices 10 that have transmitted the plurality of first telegrams are the same. That is, further, since the other devices cannot correct the radio wave intensity as described above, the distance to the transmitting device 10 that has transmitted each of the plurality of first telegrams is erroneously determined. Therefore, even if one transmitting device 10 is stationary, the other devices recognize that the plurality of transmitting devices 10 are moving. As described above, it is possible to make it more difficult for the other device to correctly determine the distance from the other device to the transmitting device 10.

Although the above embodiments have been described as typical examples, it will be apparent to those skilled in the art that many modifications and substitutions can be made within the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited by the above-described embodiments, and various modifications and modifications can be made without departing from the scope of claims.

1, 2, Distance determination system 10 Transmission device 11 Transmission setting unit 12 Transmission data creation unit 13 Control unit 14, 37, 43 Transmission unit 15 First time unit 20, 30 Distance determination device 21, 31 Reception setting unit 22, 32, 41 , 51 Reception unit 23, 33 Adjustment unit 24, 34 Distance determination unit 25, Display unit 26 Second time unit 35 Own position report unit 36 Transmission data creation unit 40 Position determination device 42 Position determination unit 50 Display device 52 Display unit

Claims (8)

It is a distance determination system including a transmitter and a distance determination device that perform wireless communication in a short distance from each other.
The transmitter is
A transmission data creation unit that creates first transmission data including a transmission device identifier for identifying the transmission device, and a transmission data creation unit.
A control unit that is changed based on a predetermined rule, and the change rule adds a transmission power identifier for identifying a known power strength in the distance determination device to the first transmission data to create second transmission data. ,
A transmission unit that transmits a first telegram including the second transmission data with the power of the power intensity is provided.
The distance determination device is
A receiving unit that receives the first telegram from the transmitting device and acquires the radio wave strength of the radio wave indicating the first telegram.
An adjusting unit that calculates the radio intensity correction value by the corresponding to the transmission power identifier included in the first message, to correct the radio field intensity based on the radio wave intensity correction coefficient that will be set based on the predetermined rule,
A distance determination unit that determines the distance from the distance determination device to the transmission device based on the radio field intensity correction value, and
A distance determination system including a display unit that displays the distance determined by the distance determination unit and the transmitter identifier included in the first telegram. The control unit adds a transmission power identifier of one of the plurality of transmission power identifiers to the first transmission data.
The distance determination system according to claim 1, wherein the transmission unit transmits the first telegram with power having the power intensity corresponding to the one transmission power identifier. The transmitting device has the transmission power identifier, the number or time during which the transmission power identifier is continuously added to the first transmission data, the order in which the transmission power identifier is added, and the power strength corresponding to the transmission power identifier. It also has a transmission setting unit that sets transmission setting information including multiple combinations with.
The control unit creates the second transmission data in which the first transmission power identifier is added to the first transmission data in the number of times, the time, and the order.
The distance determination device further includes a reception setting unit that sets reception setting information including a plurality of the transmission power identifiers and a radio wave intensity correction coefficient that is the reciprocal of the power strength corresponding to each of the transmission power identifiers.
The distance determination system according to claim 2, wherein the adjusting unit corrects the radio field intensity by using the radio wave strength correction coefficient corresponding to the one transmission power identifier included in the first telegram. The transmitter further includes a first time unit that sets the time and the transmission power identifier correspondingly.
The transmitter transmits the first telegram with a power strength corresponding to the transmission power identifier set corresponding to the current time.
The distance determination device further includes a second time unit that sets the time and the transmission power identifier correspondingly.
Claim 1 is characterized in that the adjusting unit corrects the radio wave intensity with a radio wave intensity correction coefficient corresponding to a transmission power identifier set corresponding to the time when the first telegram is received from the transmitting device. Or the distance determination system according to 2. The arbitrary field of the first telegram includes a radio field intensity field having a value indicating the relationship between the distance and the radio field intensity.
The distance determination system according to any one of claims 1 to 4, wherein the adjusting unit corrects the radio field intensity by using the value of the radio wave intensity field. The distance determination device includes a reception setting unit that sets a change rule for the transmitter identifier.
The transmission data creation unit changes the transmitter identifier according to the change rule.
The distance determination according to any one of claims 1 to 5, wherein the display unit displays the transmitter identifier before the change by the transmission data creation unit, which is specified according to the change rule. system. A distance determination system including a transmission device, a plurality of distance determination devices that perform short-range wireless communication with the transmission device, and a position determination device that receives information from the distance determination device.
The transmitter is
A transmission data creation unit that creates first transmission data including a transmission device identifier for identifying the transmission device, and a transmission data creation unit.
A control unit that is changed based on a predetermined rule, and the change rule adds a transmission power identifier for identifying a known power strength in the distance determination device to the first transmission data to create second transmission data. ,
A transmission unit that transmits a first telegram including the second transmission data to the plurality of distance determination devices with electric power of the power intensity is provided.
Each of the plurality of distance determination devices
A receiving unit that receives the first telegram from the transmitting unit of the transmitting device and acquires the radio wave intensity of the radio wave indicating the first telegram.
An adjusting unit that calculates the radio intensity correction value by the corresponding to the transmission power identifier included in the first message, to correct the radio field intensity based on the radio wave intensity correction coefficient that will be set based on the predetermined rule,
A distance determination unit that determines the distance from the distance determination device to the transmission device based on the radio field intensity correction value, and
It is provided with a transmission unit that transmits a second telegram including own position information indicating the position of the own device and distance information indicating the distance to the position determination device.
The position determination device is
A receiving unit that receives the second telegram from the transmitting unit of each of the plurality of distance determination devices, and a receiving unit.
A position determination unit that determines the position of the transmitter based on the own position information and the distance information included in each of the plurality of second telegrams.
A distance determination including a position information indicating the position of the transmission device determined by the position determination unit and a transmission unit that transmits the transmitter identifier included in the second telegram to the display device. system. It is a distance determination method executed by a transmitter and a distance determination device that perform wireless communication in a short distance from each other.
The transmitter
A step of creating first transmission data including a transmitter identifier for identifying the transmitter, and
A step of creating a second transmission data that is modified based on a predetermined rule and the modification rule adds a transmission power identifier for identifying a known power intensity in the distance determination device to the first transmission data.
A step of transmitting a first telegram including the second transmission data with the power of the power intensity is included.
The distance determination device
A step of receiving the first telegram from the transmitter and acquiring the radio wave strength of the radio wave indicating the first telegram, and
Calculating a radio wave intensity correction value by the corresponding to the transmission power identifier included in the first message, to correct the radio field intensity based on the radio wave intensity correction coefficient that will be set based on the predetermined rule,
A step of determining the distance from the distance determining device to the transmitting device based on the radio field intensity correction value, and
A distance determination method comprising the step of displaying the distance and the transmitter identifier included in the second transmission data.

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