KR20200133559A - Method for reconizing ble based a position using rssi compensation and appartus for supporting the same - Google Patents

Abstract

The present invention relates to a system for recognizing a location using Bluetooth Low Energy. According to the present invention, the system for recognizing a location using Bluetooth Low Energy comprises: a plurality of first-type beacons which periodically output Bluetooth Low Energy advertising signals; at least one second-type beacon; a server which generates an escape route; and a mobile terminal. According to the present invention, a position can be measured more accurately.

Description

BLE-based location recognition method using RSSI correction and a device to support it {METHOD FOR RECONIZING BLE BASED A POSITION USING RSSI COMPENSATION AND APPARTUS FOR SUPPORTING THE SAME}

The present invention relates to a method for measuring an indoor location of a mobile terminal, and more particularly, to a Bluetooth Low Energy (BLE) based location recognition method using RSSI correction and an apparatus for supporting the same.

Recently, as most activities such as work, entertainment, and shopping are conducted in indoor spaces, various types of location-based services provided for indoor spaces have also begun to attract attention. In particular, indoor positioning systems can be classified in a wide variety according to location accuracy, available service areas, applicable services, and applicable sensors. For example, based on location accuracy and available service area, base station, Wi-Fi, inertial navigation, high-sensitivity GNSS (Global Navigation Satellite System), UWB (Ultra Wide Band), RFID (Radio Frequency Identification), pseudo-satellite, ultrasound, It is classified as a positioning technology that utilizes various physical resources such as infrared rays, geomagnetic fields, and cameras.

Currently, fingerprinting technology using Wi-Fi has been commercialized as indoor location recognition technology. However, fingerprinting technology using Wi-Fi has the following problems. First, the fingerprinting technology using Wi-Fi is difficult to objectify because the Received Signal Strength Indicator (RSSI) value depends on the output power set in the AP because the output power can be set differently for each Wi-Fi AP. There is this. In addition, fingerprinting technology using Wi-Fi may receive interference from Wi-Fi outside a building, and Wi-Fi has a problem in that the bandwidth overlaps when using an adjacent channel, resulting in interference. In addition, for Wi-Fi, when the mobility of the user increases, the traffic status of the channel changes in real time, so RSSI must be periodically remeasured, and the Wi-Fi AP must supply power at all times and initial installation and maintenance costs are incurred. There are various problems, and it is necessary to develop a new indoor location measurement technology.

In order to solve the above-described problem and other problems, the present invention is to measure a more accurate position by filtering RSSIs outside a certain range that are not useful for location measurement among RSSIs received from a plurality of beacons. It aims to provide a method.

In order to achieve the above or other objects, according to an aspect of the present invention, in a location recognition system using low power Bluetooth including a plurality of first type beacons, at least one second type beacon, a mobile terminal and a server, low power Bluetooth A plurality of first type beacons provided with a module, periodically outputting low-power Bluetooth advertising signals, and installed in a specific space at 10m*10m intervals; At least one second type beacon provided at a low-power Bluetooth module, generating a congestion level by measuring the number of mobile terminals included in the specific space, and installed at an emergency exit; Location information and IDs of a plurality of first type beacons and second type beacons installed in the specific space, cell information composed of four first type beacons, partition information of the specific space including a plurality of cells, and the partition information Stores the received signal strength corresponding to each sector and each cell corresponding to, receives fire information and a congestion level from the at least one second type beacon, synthesizes the congestion level and gives a score to the fire information. A server for generating an escape route from a corresponding second location to a specific emergency exit; And a low power Bluetooth module, a mobile communication module, and a control unit, and the location information and ID of the plurality of first type beacons, the cell information, the compartment information, and the compartment information from the server through the mobile communication module The received signal strength corresponding to each sector and each cell is received, and from the first type beacon disposed at the corner using the ID of the first type beacon disposed at the corner of each sector through the low-power Bluetooth module Extracting the received first low-power Bluetooth received signal strength, comparing the extracted first low-power Bluetooth received signal strength with the received signal strength corresponding to each sector received from the server, and selecting a specific sector including the terminal, , Extracting a second low-power Bluetooth reception signal strength received from a first type beacon included in the specific sector using the ID of the first type beacon included in the specific sector, and extracting the second low-power Bluetooth reception signal strength By comparing the received signal strength corresponding to each cell of the specific sector to select a specific cell including the terminal, and using a third low-power Bluetooth received signal received from the four first beacons included in the specific cell The first location is specified by calculating the distance between the first location and the four first type beacons included in the specific cell by triangulation method, and receiving fire information and escape route from the server And a mobile terminal displayed on a map, wherein the low-power Bluetooth received signal strength for the plurality of first type beacons is in a range of -40dBm to -95dBm.

In addition, in the present specification, the congestion level is determined according to the number of mobile terminals measured by the second type beacon installed at the emergency exit of the specific space.

In addition, in the present specification, the level of congestion is characterized by having a higher level as the number of determined mobile terminals increases.

In the present specification, among RSSIs (Received Signal Strength Indicators) received from a plurality of beacons, RSSIs outside a certain range, which are not useful for location measurement, are filtered, so that a more accurate location can be measured.

Further scope of applicability of the present invention will become apparent from the detailed description below. However, since various changes and modifications within the spirit and scope of the present invention can be clearly understood by those skilled in the art, specific embodiments such as the detailed description and preferred embodiments of the present invention should be understood as being given by way of example only.

1 is a flowchart illustrating a location recognition method using low-power Bluetooth related to the present invention.
FIG. 2 is a flowchart illustrating a method of displaying fire information among a location recognition method using low-power Bluetooth related to the present invention.
3 is a flowchart illustrating a method of displaying an escape route reflecting fire information and congestion level information among the location recognition methods using low-power Bluetooth related to the present invention.
4 is a conceptual diagram of a location recognition system using low-power Bluetooth related to the present invention.
5 is a block diagram of a mobile terminal supporting a location recognition method using low-power Bluetooth related to the present invention.
6 to 8 are views for explaining a specific embodiment of a location recognition method using low-power Bluetooth related to the present invention.
9 is a diagram showing an example of an internal block diagram for performing the method proposed in the present specification.
10 is a diagram showing an example of an advertisement data message format proposed in the present specification.
11 shows an example of a method of filtering garbage RSSI proposed in the present specification.

Hereinafter, exemplary embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but identical or similar elements are denoted by the same reference numerals regardless of reference numerals, and redundant descriptions thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used interchangeably in consideration of only the ease of preparation of the specification, and do not have meanings or roles that are distinguished from each other by themselves. In addition, in describing the embodiments disclosed in the present specification, when it is determined that a detailed description of related known technologies may obscure the subject matter of the embodiments disclosed in the present specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed in the present specification is not limited by the accompanying drawings, and all modifications included in the spirit and scope of the present invention It should be understood to include equivalents or substitutes.

Terms including ordinal numbers, such as first and second, may be used to describe various elements, but the elements are not limited by the terms. These terms are used only for the purpose of distinguishing one component from another component.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. Should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In the present application, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

Mobile terminals described in this specification include mobile phones, smart phones, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), navigation systems, and slate PCs. , Tablet PC (tablet PC), ultrabook (ultrabook), wearable device (wearable device, for example, smartwatch, glass-type terminal (smart glass), HMD (head mounted display)), etc. may be included. have.

1 is a flowchart illustrating a location recognition method using low-power Bluetooth related to the present invention. Hereinafter, a method for recognizing a location using low-power Bluetooth will be described in detail with reference to FIG. 1.

Referring to FIG. 1, a method for recognizing a location using low-power Bluetooth related to the present invention includes a first type beacon 100, a second type beacon 200 installed in a specific space, a mobile terminal 300 entering a specific space, and Indoor location information of the mobile terminal 300 may be specified by interaction between the servers 400 managing information of a specific space. At this time, the type 1 beacon 100, the type 2 beacon 200, the mobile terminal 300 entering a specific space, and the server 400 that manages information of a specific space include low-power Bluetooth communication, Wi-Fi or wireless Internet communication. , And mobile communication may be used to transmit a signal or information.

Low-power Bluetooth 4.0 (BLE: Bluetooth Low Energy) communication method is composed of a connection mode (connection mode) and an advertise mode (advertise mode). Connection mode is an operation mode in which two devices are paired with a Bluetooth communication method and then data communication is performed one-to-one.Advertise mode is an operation mode that unilaterally transmits an advertising signal to the surroundings without specifying a specific device. This is an operation mode that searches for nearby devices.

The first type beacon according to the present invention can operate only in an advertise mode, and the second type beacon can operate in two modes, a connection mode and an advertise mode.

First, the server 400 receives the location information and the ID of the first type beacon from the first type beacon 100 (S110-1), and the location information of the second type beacon from the second type beacon 200 , The ID can be received (S110-2).

Here, the first type beacon 100 is a beacon for simple location recognition, and may be installed in a specific space at 10m*10m intervals. The first type beacon 100 periodically transmits a Non-Connectable Advertising Packet in order to provide only an advertising function. Non-Connectable Advertising Packet refers to a method of transmitting a signal with a small data size to the surroundings without specifying a specific device. The first type beacon 100 may be an iBeacon.

The second type beacon 200 is installed at an emergency exit location in a specific space, and may be linked with a backbone network by collecting congestion level information and fire information using power supplied to the emergency exit. The second type beacon 200 may use an Undirected Connectable Advertising Packet, and may use Wi-Fi or Ethernet by providing an additional communication module (eg, Raspberry pi3).

Next, the location information of the first type/second type beacon received from the server 400, ID, cell information, partition information (or sector information), and received signal strength corresponding to each sector and each cell may be stored. (S120).

The server 400 uses a fingerprinting method and a triangulation method step by step, based on the information received from the second type beacon 200 and the mobile terminal 300, the location information of the mobile terminal 300 in a specific space. Can be specified.

The fingerprinting method is a method of selecting a reference position in a service area, collecting signal strength information, and estimating the position through signal strength information received from a mobile terminal based on the collected information. To use the finger printing method, It is necessary to store low-power Bluetooth radio wave characteristics in the database in advance.

The triangulation method is a method of calculating the location of the mobile terminal based on the coordinates of at least three beacons and the distance between the mobile terminal. In order to measure the distance between the mobile terminal and the beacon, the signal strength is converted into distance information, or the time at which the radio signal is transmitted (Time of Arrival, ToA), the time difference at which the signal is transmitted (Time Difference of Arrival, TDoA), It is possible to use the angle (Angle of Arrival, AoA) through which the signal is transmitted.

The server 400 stores partition information of a specific space, each sector, and the received signal strength corresponding to each cell, so that the mobile terminal using a fingerprinting method using the low-power Bluetooth received signal strength transmitted from the mobile terminal 300 later. 300) can be calculated.

The first type beacon 100 may periodically output a low-power Bluetooth signal (S130). As described above, the first type beacon 100 does not transmit an advertising signal by designating a target device, but the target device (mobile terminal 300) is located within the range in which the advertising signal is transmitted. In this case, the target device (mobile terminal 300) may receive an advertising signal. In this case, a plurality of first type beacons 100 installed in a specific space may output an advertising signal having a predetermined size.

When the mobile terminal 300 receives the advertising signal output from the first type beacon 100, the mobile terminal 300 may measure the strength of the low-power Bluetooth reception signal (S140). The mobile terminal 300 is located at a first location in a specific space and may measure the received signal strength of the low-power Bluetooth advertising signal received at the first location. In this case, the advertising signal may include the ID of the first type beacon 100.

The mobile terminal 300 may request the server 400 for location information and IDs of a plurality of first type beacons, cell information, partition information, and received signal strength corresponding to each sector and each cell (S150). The mobile terminal 300 is a first type beacon disposed at the corner (or center) of each sector of the received low-power Bluetooth received signal strength using the ID of the received advertising signal and the information transmitted from the server 400. The strength of the first low-power Bluetooth received signal received from may be extracted (S160).

The mobile terminal 300 may compare the extracted first low-power Bluetooth received signal strength with the received signal strength corresponding to each sector stored in the database to select a specific sector including the first location (S170).

Specifically, the mobile terminal 300 may select a specific sector including the first location by applying a fingerprinting method for each sector. In the conventional method, since the fingerprinting method is applied for each cell, there is a problem with a large amount of computation. In the present invention, the amount of computation can be reduced by applying the fingerprinting method for each sector by partitioning the sectors. For example, when four cells are divided into one sector, instead of comparing the strength of low-power Bluetooth received signals received from nine beacons, low-power Bluetooth reception received from four beacons located at the corner (or center) of the sector You can select a specific sector by comparing the signal strength. When selecting a specific sector by comparing the strength of the low-power Bluetooth reception signal, two or more sectors may be selected in consideration of an error value.

The mobile terminal 300 may extract the strength of the second low-power Bluetooth received signal received from the first type beacon included in the specific sector by using the ID of the first type beacon included in the specific sector (S180). Here, the first low-power Bluetooth signal and the second low-power Bluetooth signal do not indicate temporal precedence, but are used to distinguish the low-power Bluetooth signal received from the first type beacon of a specific group.

The mobile terminal 300 may select a specific cell including the first location by comparing the extracted second low-power Bluetooth received signal strength with the received signal strength corresponding to each cell (S190). The method of selecting a specific cell is similar to the method of selecting a specific sector described above, and a specific cell may be selected by comparing the strength of the low-power Bluetooth received signal of each cell stored in the database of the server with the specific received signal strength. In this case, two or more specific cells may be selected in consideration of an error value.

The mobile terminal 300 may specify the first location by using a three-sided survey method using a third low-power Bluetooth reception signal received from the first type beacon included in the selected specific cell (S200).

Specifically, when one specific cell is selected, the mobile terminal 300 uses the third low-power Bluetooth reception signal received from the four first type beacons included in the specific cell, and uses the first location and the 4 included in the specific cell. The distance to the dog's first type beacons can be calculated using a trilateral survey method. The mobile terminal 300 may determine the first location by using the distance to the first type beacon calculated by the trilateral survey method. In this case, the mobile terminal 300 may calculate the distance for all four first type beacons included in a specific cell, and select only three of the four first type beacons to calculate the distance.

FIG. 2 is a flow chart illustrating a method for displaying a location recognition method using low-power Bluetooth related to the present invention, and FIG. 3 is a flowchart illustrating a method for displaying an escape route reflecting fire information and congestion information related to the present invention. It is a flow chart.

Referring to FIG. 2, the method of displaying fire information related to the present invention includes low-power Bluetooth communication between the second type beacon 200, the mobile terminal 300, and the server 400 located in a specific space, Wi-Fi or wireless Internet. Communication, and mobile communication.

The server 400 may receive fire information of a second location included in a specific space from the second type beacon 200 (S210), and transmit fire information of the second location to the mobile terminal 300 (S220). .

Specifically, the second type beacon 200 may periodically receive a low power Bluetooth advertising signal through the first type beacon 100 installed at regular intervals. In the second type beacon 200, when an advertising signal is not received from a specific first type beacon among the first type beacons 100 installed in a specific space, a fire occurs at a location where a specific first type beacon is installed. I can judge.

The mobile terminal 300 may display fire information, the first location, and the second location on a map of a specific space (S230). In this case, the mobile terminal 300 may display an area in which a specific first type beacon is installed without transmitting an advertising signal as a blocking area.

Referring to FIG. 3, the second type beacon 200 and the mobile terminal 300 set up low-power Bluetooth communication, and the second type beacon 200 may directly transmit a congestion level to the mobile terminal 300 (S310). .

In addition, the second type beacon 200 may transmit a congestion level to the server 400 (S320). The congestion level may be determined by the number of mobile terminals measured by a second type beacon installed at an emergency exit in a specific space. For example, when the number of mobile terminals is 0 to 2, 0 points, 3 to 5, 1 point, 6 to 8, 2 points, etc., the congestion level information may be indicated.

The server 400 may update the fire information (S330) and generate an escape route by reflecting the updated fire information and the congestion level (S340).

The server 400 may include location information of a second type specific beacon to which a response signal is not transmitted among at least one second type beacon in the fire information and display it on a map of a specific space. The server 400 may determine an escape route from the first location to the specific emergency exit by using the congestion level received from at least one second type beacon and location information of the second type specific beacon.

The server 400 may directly transmit the updated fire information, congestion level, and escape route information to the mobile terminal 300 (S350-1) or to the mobile terminal 300 through the second type beacon 200. (S350-2).

The mobile terminal 300 may display a fire location, a congestion level, and an escape route on a specific space map (S360). Specifically, the mobile terminal 300 may display a fire location on a specific space map with a specific icon, display a block area due to a fire, and display a congestion level by color. In addition, an escape route determined based on a congestion level and a fire location may be displayed on a map so that a user can intuitively check the evacuation route.

4 is a conceptual diagram of a location recognition system using low-power Bluetooth related to the present invention, and FIG. 5 is a block diagram of a mobile terminal supporting a location recognition method using low-power Bluetooth related to the present invention.

Referring to FIG. 4, a location recognition system using low-power Bluetooth may include a first type beacon 100, a second type beacon 200, a mobile terminal 300, and a server 400. Here, the first type beacon 100, the second type beacon 200, and the mobile terminal 300 may be installed or disposed in a specific space. The server 400 may be installed in a specific space or may be installed in another place outside.

Specifically, the plurality of first type beacons 100 may include low-power Bluetooth modules, periodically output a low-power Bluetooth advertising signal, and may be installed in a specific space at 10m*10m intervals.

At least one second type beacon 200 includes a low-power Bluetooth module, generates a congestion level by measuring the number of mobile terminals included in the specific space, and may be installed at an emergency exit. That is, when seven emergency exits are installed in a specific space, seven second type beacons 200 may be installed.

The server 400 includes location information and IDs of a plurality of first type beacons and second type beacons installed in a specific space, cell information composed of four first type beacons, partition information of a specific space including a plurality of cells, and Each sector corresponding to the segment information and a received signal strength corresponding to each cell may be stored in the database.

The server 400 may generate an escape route from a second location corresponding to the fire information to a specific emergency exit by receiving fire information and a congestion level from at least one second type beacon, and assigning a score by synthesizing the congestion level. have.

At this time, the server 400 measures the strength of the first low-power Bluetooth received signal from the first type beacon installed at the corner (or center) of each sector for arbitrary positions included in each sector, and applies a Kalman filter. After application, the received signal strength corresponding to each sector can be stored. In addition, the server 400 measures the strength of a second low-power Bluetooth received signal from a first type beacon installed in each cell for arbitrary locations included in each cell, and then responds to each cell after applying a Kalman filter. It can be stored as the received signal strength.

Referring to FIG. 5, the mobile terminal 300 may include a low-power Bluetooth module, a mobile communication module, and a control unit.

The control unit 320 of the mobile terminal 300 is transmitted from the server 400 through the mobile communication module 314 to provide location information and IDs, cell information, partition information, and sectors corresponding to the partition information. And a received signal strength corresponding to each cell.

The control unit 320 of the mobile terminal receives from the first type beacon disposed at the corner (or center) by using the ID of the first type beacon disposed at the corner (or center) of each sector through the low-power Bluetooth module 312 A first low-power Bluetooth received signal strength may be extracted. In addition, the control unit 320 of the mobile terminal may select a specific sector including the terminal by comparing the extracted first low-power Bluetooth received signal strength with the received signal strength corresponding to each sector received from the server 400.

The control unit 320 of the mobile terminal extracts the strength of the second low-power Bluetooth received signal received from the first type beacon included in the specific sector using the ID of the first type beacon included in the specific sector, and the extracted second low power A specific cell including the terminal may be selected by comparing the received signal strength of Bluetooth with the strength of a received signal corresponding to each cell of a specific sector.

The control unit 320 of the mobile terminal uses the third low-power Bluetooth reception signal received from the four first beacons included in the specific cell to reach the first location of the mobile terminal and the four first type beacons included in the specific cell. The first location can be specified by calculating the distance by triangulation.

In addition, the control unit 320 of the mobile terminal 300 may receive fire information and an escape route from the server 400 and display it on a map of a specific space of the display module 332. The control unit 320 of the mobile terminal may output a sound effect through the sound output module 334 when a fire occurs.

The control unit 320 of the mobile terminal responds to fire information by receiving fire information, a congestion level, a map of a specific space, and an escape route through the second type beacon 200 installed in a specific space through the low-power Bluetooth module 312 The second location and the escape route from the first location of the terminal 300 to the specific emergency exit may be displayed on a map of a specific space.

In addition, the mobile terminal may additionally include a Map module, a positioning module, a Beacon module, and an RSSI modeling module, as shown in FIG. 9.

9 is a diagram showing an example of an internal block diagram for performing the method proposed in the present specification.

The Map module, the positioning module, the Beacon module, and the RSSI modeling module may be included in and implemented in a control unit, or may be implemented by being included in one module separately from the control unit, or may be implemented separately.

The Map module includes Radio Map and Indoor Map, the positioning module includes KNN and Vector, the Beacon module may include Beacon information and Beacon Scanner, and the RSSI modeling module includes Kalman Filter and Garbage. Can include.

Then, the mobile terminal receives advertisement data (or advertisement message) from the Bluetooth device through the module shown in FIG. 9.

The advertisement data may be expressed as a beacon, and the beacon may include UUID, MAC Address, Tx Power, RSSI, and the like.

In addition, the mobile terminal may receive a plurality of beacons, and each beacon may include salpin information.

In addition, the advertisement data or beacon may have a message format as shown in FIG. 10.

That is, the advertisement data or beacon may be expressed as RSSI_Value_Tx.

The RSSI_Value_Tx includes a header, a payload, and a CRC.

The header may include destination_address, Source_address, Sequence_No, Length, and Payload ID, and the size of each field may be as shown in FIG. 10.

In addition, the payload may include Beacon_B_ID, Tx_Power, and Adv_interval.

10 is a diagram showing an example of an advertisement data message format proposed in the present specification.

6 to 8 are diagrams for explaining a specific embodiment of a location recognition method using low-power Bluetooth related to the present invention.

6 to 8, the location recognition method using low-power Bluetooth related to the present invention selects a specific sector in which a mobile terminal is located, then selects a specific cell among specific sectors, and then specifies specific location information within a specific cell. can do. That is, the location recognition method using low-power Bluetooth related to the present invention may be performed in a specific order of specific sector selection, specific cell selection, and specific location information using a trilateral survey method.

Referring to FIG. 6, the server may install a first type beacon at 10m*10m intervals in a specific space and divide N cells into M sectors. Specifically, when 16 cells are included in a specific space, the server can be divided into 4 sectors. In this case, the cell represents an area surrounded by four first type beacons, and the sector may be set as square cells partitioned by the server.

The server can group 16 cells into 4 sectors by grouping them into 4 sectors, and store the IDs of each cell and each sector, and the strength of a low-power Bluetooth received signal in a database in advance. In this case, the received signal strength stored in the database refers to the strength of the low-power Bluetooth received signal measured through a number of experiments.

The server receives the first low-power Bluetooth received signal strength received from the first type beacon installed at each corner (or center) of Sector1, Sector2, Sector3, and Sector4 from the mobile terminal, and can select which sector the mobile terminal is included in. . That is, the server may compare the strength of the first low-power Bluetooth received signal received from the mobile terminal with the strength of the low-power Bluetooth received signal for each sector stored in the database, and select the most similar sector as a specific sector in which the mobile terminal exists.

For example, if the server determines that the strength of the first low-power Bluetooth received signal received from the mobile terminal is most similar to the strength of the low-power Bluetooth received signal corresponding to Sector4, the server may select that the mobile terminal is included in Sector4.

In addition, the server may select which cell the mobile terminal is included in by using the strength of the second low-power Bluetooth received signal received from the first type beacon included in Cell11, Cell12, Cell15, and Cell16 included in Sector4.

Referring to FIG. 7, similar to the above sector selection method, it may be determined by comparing the strength of the low-power Bluetooth received signal of each cell stored in the database of the server with the strength of the second low-power Bluetooth received signal.

As a result of the comparison, when it is determined that the mobile terminal is included in Cell 16, the server uses the third low-power Bluetooth received signal strength received from the four first type beacons included in Cell 16 to determine the first location (P ) And the distance to the four first-type beacons can be calculated using a trilateral survey method.

That is, d1, d2, d3, d4, which are the distances between the first location P of the mobile terminal and the four first type beacons, can be calculated, and by using this, the coordinates of the first location P, (1.41, 3.32) can be specified.

Referring to FIG. 8, the mobile terminal may display a map of a specific space received from a server on the display module 332. In addition, the mobile terminal may display the calculated first location P on a map of a specific space.

When the mobile terminal receives the fire information and the level of congestion from the server, the mobile terminal may display a fire area on a map of a specific space and display the level of congestion (a, b, c) of each gate in different colors.

When the mobile terminal receives information on the escape route (l) from the first location (P) of the mobile terminal to the emergency exit using the fire information and the congestion level from the server, it can display it on a map of a specific space.

Accordingly, according to the present invention, by selecting a sector and a cell for the current location of the mobile terminal in the mobile terminal or the server, and then calculating the location in a specific cell, the current location can be calculated quickly, and fire information related to a specific space by the mobile terminal, By providing an escape route along with a congestion level, a mobile terminal user can evacuate the fire site with an optimal escape route.

Salpin above, the mobile terminal is a low-power Bluetooth module; Mobile communication module; And a control unit.

In particular, the control unit includes location information and IDs of a plurality of first type beacons installed in a specific space from the server through the mobile communication module, cell information composed of four first type beacons, and the specific space including a plurality of cells. The segment information and the received signal strength corresponding to each sector and each cell corresponding to the segment information are received, and an ID of a first type beacon disposed at a corner (or center) of each sector through the low-power Bluetooth module Using the extracted first low-power Bluetooth received signal strength received from the first type beacon disposed in the corner (or in the center), the extracted first low-power Bluetooth received signal strength and each sector received from the server The second low-power Bluetooth received from the first type beacon included in the specific sector by comparing the corresponding received signal strength to select a specific sector including the terminal, and using the ID of the first type beacon included in the specific sector The received signal strength is extracted, the extracted second low-power Bluetooth received signal strength is compared with the received signal strength corresponding to each cell of the specific sector to select a specific cell containing the terminal, and included in the specific cell. The first location is specified by calculating the distance between the first location and the four first type beacons included in the specific cell using a third low-power Bluetooth reception signal received from the four first beacons using a triangulation method. Characterized in that.

BLE fingerprinting using RSSI correction

Hereinafter, a BLE fingerprinting method using RSSI correction proposed in the present specification will be described. For the description of BLE fingerprinting other than the RSSI correction method, the above-mentioned contents can be applied in the same manner, and the above-mentioned contents will be referred to for related parts.

That is, the present specification collects raw RSSI from a plurality of beacons in order to perform more accurate BLE fingerprinting, filters RSSIs corresponding to a specific range, that is, garbage, among the collected raw RSSIs, and the remaining RSSIs A method of performing the above-mentioned positioning algorithm through corrected RSSIs after noise is corrected by applying a Kalman filter to the Kalman filter is provided.

Here, the reason why RSSI corresponding to garbage is additionally filtered is because other Bluetooth devices that are not actually used for location measurement are included.

Here, what corresponds to garbage RSSI, that is, an RSSI corresponding to a specific range may mean an RSSI that does not fall within the -40 ~ -95dBm range.

11 shows an example of a method of filtering garbage RSSI proposed in the present specification.

The mobile terminal measures RSSI number N from 9 in Beacon 1. N may be 1200, for example.

Next, the mobile terminal filters garbage RSSIs that are not in a certain range among the N raw RSSIs using a garbage filter.

Here, the predetermined range may mean -40 to -95dBM. For example, if there are 200 garbage RSSIs that are not in the predetermined range among 1200 RSSIs, the number of RSSIs that can actually be used for BLE fingerprinting among 1200 RSSIs is 1000.

Next, the mobile terminal corrects noise for RSSI using a Kalman filter for RSSIs (eg, 1,000) excluding garbage RSSI.

Next, the mobile terminal applies an algorithm for positioning, that is, BLE fingerprinting, for the corrected RSSSIs using KNN and Vector.

Table 1 is a table showing an example of distances according to RSSI.

RSSI Distance(m) -40dBm 0.06309 -95dBm 14.1253

The distance according to the RSSI of Table 1 may be calculated according to Equation 1 below.

In Equation 1, D represents a distance, n represents a correction constant related to propagation loss, Tx power represents a transmission strength, and RSSI represents an RSSI of a beacon.

Here, Tx power may be set to -64dbm, and n may be set to n=2 assuming that there are no obstacles around.

Hereinafter, based on the above description, an RSSI correction and a location recognition method using low-power Bluetooth will be described.

First, the server corresponds to location information and IDs of a plurality of first type beacons installed in a specific space, cell information consisting of four first type beacons, partition information of the specific space including a plurality of cells, and the partition information. The received signal strength corresponding to each sector and each cell is stored.

And, the mobile terminal measures the strength of a low-power Bluetooth received signal from a plurality of first type beacons installed in the specific space at a first location included in the specific space.

The mobile terminal requests and receives the location information and IDs, cell information, partition information, and received signal strengths corresponding to each sector and each cell from the server.

And, the mobile terminal is installed at the corner (or center) using the ID of the first type beacon disposed at the corner (or center) of each sector among the low-power Bluetooth received signal strength of the new first type beacon. The strength of the first low-power Bluetooth received signal received from the first type beacon is extracted.

The mobile terminal selects a specific sector including the first location by comparing the extracted first low-power Bluetooth received signal strength with the received signal strength corresponding to each sector.

Further, the mobile terminal extracts the strength of the second low-power Bluetooth received signal received from the first type beacon included in the specific sector by using the ID of the first type beacon included in the specific sector.

In addition, the mobile terminal selects a specific cell including the first location by comparing the extracted second low-power Bluetooth received signal strength with the received signal strength corresponding to each cell.

In addition, the mobile terminal uses a third low-power Bluetooth reception signal received from the four first-type beacons to determine the distance between the first location and four first-type beacons included in the specific cell by a trilateral survey method. It calculates and specifies the said 1st position.

Here, the strength of the low-power Bluetooth received signal for the plurality of first type beacons may range from -40dBm to -95dBm.

Additionally, when the server collects fire information of a second location included in the specific space, the server transmits the fire information to the mobile terminal.

In addition, the mobile terminal displays the fire information, the first location, and the second location on a map of the specific space.

In addition, the server receives the level of congestion from at least one second type beacon installed at the emergency exit of the specific space.

In addition, the server includes the location information of the second type specific beacon to which a response signal is not transmitted among the at least one second type beacon in the fire information and displays it on the map of the specific space.

In addition, the server uses the congestion level received from the at least one second type beacon and the location information of the second type specific beacon to determine an escape route from the first location to a specific emergency exit on the map of the specific space. Mark on.

In addition, the level of congestion may be determined according to the number of mobile terminals measured by the second type beacon installed at the emergency exit of the specific space.

In addition, the congestion level may have a higher level as the number of the determined mobile terminals increases.

The present invention described above can be implemented as a computer-readable code in a medium on which a program is recorded. The computer-readable medium includes all types of recording devices that store data that can be read by a computer system. Examples of computer-readable media include HDD (Hard Disk Drive), SSD (Solid State Disk), SDD (Silicon Disk Drive), ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, etc. There is also a carrier wave (e.g., transmission over the Internet). Also, the computer may include the controller 180 of the terminal. Therefore, the detailed description above should not be construed as restrictive in all respects and should be considered as illustrative. The scope of the present invention should be determined by rational interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

100: first type beacon 200: second type beacon
300: mobile terminal 400: server

Claims (3)

In a location recognition system using low-power Bluetooth including a plurality of first type beacons, at least one second type beacon, a mobile terminal, and a server,
A plurality of first type beacons having a low-power Bluetooth module, periodically outputting a low-power Bluetooth advertising signal, and installed in a specific space at 10m*10m intervals;
At least one second type beacon provided in a low-power Bluetooth module, generating a congestion level by measuring the number of mobile terminals included in the specific space, and installed at an emergency exit;
Location information and IDs of a plurality of first type beacons and second type beacons installed in the specific space, cell information composed of four first type beacons, partition information of the specific space including a plurality of cells, and the partition information Stores the received signal strength corresponding to each sector and each cell corresponding to, receives fire information and a congestion level from the at least one second type beacon, synthesizes the congestion level and gives a score to the fire information. A server for generating an escape route from a corresponding second location to a specific emergency exit; And
It has a low-power Bluetooth module, a mobile communication module, and a control unit, and corresponds to the location information and ID of the plurality of first type beacons, the cell information, the compartment information, and the compartment information from the server through the mobile communication module. The received signal strength corresponding to each sector and each cell is received, and received from the first type beacon disposed at the corner using the ID of the first type beacon disposed at the corner of each sector through the low-power Bluetooth module A first low-power Bluetooth received signal strength is extracted, and the extracted first low-power Bluetooth received signal strength is compared with the received signal strength corresponding to each sector received from the server to select a specific sector including the terminal, Using the ID of the first type beacon included in the specific sector, a second low-power Bluetooth received signal strength received from the first type beacon included in the specific sector is extracted, and the extracted second low-power Bluetooth received signal strength and By comparing the received signal strength corresponding to each cell of the specific sector, selecting a specific cell including the terminal, and using a third low-power Bluetooth reception signal received from the four first beacons included in the specific cell. The first location is specified by calculating the distance between the first location and the four first type beacons included in the specific cell by a triangulation method, and a map of the specific space by receiving fire information and escape routes from the server Including a mobile terminal to display on the,
A location recognition system using low-power Bluetooth, characterized in that the low-power Bluetooth received signal strength for the plurality of first type beacons is within a range of -40dBm to -95dBm. The method of claim 1,
The congestion level is determined according to the number of mobile terminals measured by a second type beacon installed at the emergency exit of the specific space. The method of claim 2,
The location recognition system using low-power Bluetooth, wherein the congestion level has a higher level as the number of the determined mobile terminals increases.

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