KR102362314B1 - Apparatus and method building radio map - Google Patents

Abstract

Disclosed are an apparatus and method for constructing a radio wave map capable of constructing a radio map with high reliability in a short time. According to an aspect, an apparatus for constructing a propagation map for a main area and a plurality of detailed areas includes: a storage unit configured to store a propagation map for each area; a first construction module for generating a propagation map based on a plurality of nodes for the main region and storing the generated propagation map in the storage unit; an analysis module for classifying the plurality of detailed regions into regions corresponding to each other based on an internal structure and external physical characteristics based on the plurality of nodes; and a second construction module for generating a propagation map for any one of the areas corresponding to each other, generating a propagation map of the remaining areas using a propagation pattern of the propagation map, and storing the generated propagation map in the storage unit.

Description

Apparatus and method for building a radio wave map {APPARATUS AND METHOD BUILDING RADIO MAP}

The present invention relates to a location measurement technique, and more particularly, to an apparatus and method for constructing a radio wave map for constructing a radio map used for location measurement.

Recently, as the use of smartphones increases, a location-based service (LBS) market that provides various services using location information is activated. Location-based service refers to a system and service based on location information that comprehensively utilizes mobile communication networks and IT technology. is provided with

Conventionally, a GPS (Global Positioning System) method or a method using a base station of a mobile communication network is widely used as a positioning technology. However, the GPS method generally has an error of several meters or more, and has disadvantages in that it is impossible to position in a shaded area such as a building or a tunnel. Unlike the GPS method, the method using a base station to which a user terminal such as a smartphone is connected has the advantage of being able to position both indoors and outdoors. There is this.

In order to overcome these problems, there is a need for a technology that has relatively high accuracy and requires little additional cost for positioning. Recently, research on positioning technology using a wireless access point that can satisfy these needs is being actively researched. This is because access points for a wireless LAN (WLAN) service are already installed in numerous places, so there is no need to additionally install a separate base station, and because the access points are densely installed, positioning accuracy is high.

As a representative method of a positioning service using such an access point, there is a radio map method. The radio map-based position measurement has the advantage of low dependence on channel characteristics and stable positioning. A general propagation map method is to estimate the location of a user terminal by using a propagation map storing radio signal propagation patterns for various areas within a specific area. When a user terminal that is a location measurement target receives a radio signal, the user terminal compares the propagation pattern of the radio signal received by the user terminal with the propagation pattern stored in the propagation map, and determines an area having the most similar propagation pattern as the location of the user terminal.

In order to measure a location using the radio map method, a radio map must be built in advance. A static collection method is usually utilized to generate the propagation map. In the static collection, a number of nodes to collect the propagation pattern are designated in advance in the collection area, and the radio wave collecting device waits for a few minutes at the exact location of each node and collects the radio signal to collect the propagation pattern for each node, that is, the radio fingerprint. create In this case, it is common to designate the node, which is the collection point of the propagation pattern, as the center position of each grid after dividing the collection area into a grid shape. When the propagation fingerprints of several nodes generated in this way are integrated, a radio map is generated. However, since the static collection method requires a collection time of several minutes each at many collection points in the indoor space, there is a problem that too much manpower and time are required for collection. To solve this problem, a dynamic collection method has been proposed. Unlike static collection, the dynamic collection method uses a built-in sensor or GPS to know the real-time location and collects radio wave patterns while continuously moving through the collection area using a collection device that can collect wireless signals at the same time. When the collector carries the collection device and moves within the collection area, the collection device automatically measures the collection location where the radio wave pattern is being collected according to the situation and records the corresponding propagation pattern, so that the collection proceeds. However, even in this dynamic collection method, it is necessary to wait until a sufficient number of propagation patterns are collected within the collection area. As described above, the conventional method of constructing a radio map has disadvantages in that it requires a lot of initial construction cost and needs to periodically update the radio map because the signal strength can be continuously changed. In particular, since the renewal process requires a cost similar to the initial cost, it becomes a significant economic burden in terms of management.

In order to solve such a problem, a crowdsourcing method using general user terminals using a mobile communication service has been proposed. It builds a radio map based on information collected by a large number of users who are not managed without a separate professional manpower input, and performs positioning based on the radio map. This has the advantage of reducing the initial construction cost as well as the maintenance cost. However, when constructing a propagation map using only crowdsourcing, it takes a long time to build a reliable propagation map. It is necessary to limit the area that has correlation through Therefore, it takes a long time compared to the supervised-based propagation map construction method.

The present invention has been proposed to solve the above-mentioned problems, and a radio map construction apparatus capable of constructing a radio map with high reliability in a short time by fusing a supervised radio map construction method and a crowdsourcing-based radio map construction method, and The purpose is to provide a method.

According to an aspect, an apparatus for constructing a propagation map for a main area and a plurality of detailed areas includes: a storage unit configured to store a propagation map for each area; a first construction module for generating a propagation map based on a plurality of nodes for the main region and storing the generated propagation map in the storage unit; an analysis module for classifying the plurality of detailed regions into regions corresponding to each other based on an internal structure and external physical characteristics based on the plurality of nodes; and a second construction module for generating a propagation map for any one of the areas corresponding to each other, generating a propagation map of the remaining areas using a propagation pattern of the propagation map, and storing the generated propagation map in the storage unit.

The analysis module may classify regions in which internal structures including internal shapes and sizes correspond to each other, and external physical properties including propagation patterns in external nodes based on the location of the entrance and exit correspond to each other.

In the regions corresponding to each other, propagation patterns in external nodes that are spaced the same distance from the entrance and vertically connected from the entrance may correspond to each other.

External nodes vertically connected from the entrances of the regions corresponding to each other may be spaced apart from the intersection nodes by a predetermined distance or more.

The propagation pattern may include a pattern of signal strength.

The analysis module may classify regions in which an internal structure including an internal shape and size and a location of an entrance are symmetric with respect to a node and a propagation pattern in a node corresponds to each other.

The second building module receives radio wave information from one or more user terminals that have collected radio wave information in each of the remaining areas, and combines the identification information of the radio wave transmitting device extracted from the received radio wave information to the propagation pattern of the one area By doing so, it is possible to generate a propagation map of the remaining regions.

A method of constructing a propagation map for a main area and a plurality of detailed areas in an apparatus for constructing a propagation map according to another aspect includes generating a propagation map based on a plurality of nodes for the main area and storing the generated propagation map in a storage unit step; classifying the plurality of detailed regions into regions corresponding to each other based on an internal structure and external physical characteristics based on the plurality of nodes; and a second construction step of generating a propagation map for any one of the areas corresponding to each other, generating a propagation map of the remaining areas using a propagation pattern of the propagation map, and storing the generated propagation map in the storage unit.

The classifying may classify regions in which internal structures including internal shapes and sizes correspond to each other, and external physical properties including propagation patterns in external nodes based on the location of the entrance and exit correspond to each other.

In the regions corresponding to each other, propagation patterns in external nodes that are spaced the same distance from the entrance and vertically connected from the entrance may correspond to each other.

External nodes vertically connected from the entrances of the regions corresponding to each other may be spaced apart from the intersection nodes by a predetermined distance or more.

The propagation pattern may include a pattern of signal strength.

In the classifying step, the internal structure including the internal shape and size and the location of the doorway are symmetrical with respect to one node, and regions in which the propagation pattern in the one node corresponds to each other may be classified.

In the second construction step, radio wave information is received from one or more user terminals that have collected radio wave information in each of the remaining areas, and identification information of a radio wave transmitting device extracted from the received radio wave information is combined with a propagation pattern of the one area. By doing so, it is possible to generate a propagation map of the remaining regions.

According to an embodiment of the present invention, it is possible to reduce the time and cost required to construct the initial propagation map.

According to an embodiment of the present invention, a propagation map can be built with less data compared to the conventional crowdsourcing method.

1 is a diagram illustrating a system according to an embodiment of the present invention.
2 is a view showing an indoor view according to an embodiment of the present invention.
3 is a diagram illustrating the configuration of an apparatus for constructing a radio wave map according to an embodiment of the present invention.
4 is a flowchart illustrating a method of constructing a propagation map according to an embodiment of the present invention.

The above-described objects, features, and advantages will become more apparent through the following detailed description in relation to the accompanying drawings, whereby those of ordinary skill in the art to which the present invention pertains can easily implement the technical idea of the present invention. There will be. In addition, in the description of the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a system according to an embodiment of the present invention. As shown in FIG. 1 , the system according to the present embodiment includes one or more user terminals 100 , a radio wave map construction apparatus 300 , and a communication network 200 connecting them.

The user terminal 100 is a device that can be carried and moved, and can communicate with other user terminals and the radio wave map construction apparatus 300 using a communication channel. An embodiment of the user terminal 100 may include, but is not limited to, a portable device such as a mobile phone and a smart phone, a tablet computer, a computing device having a Wi-Fi or other wireless transceiver such as a laptop computer, or a similar device. does not The number of user terminals 100 shown in FIG. 1 is merely an example and is not limited thereto. The user terminal 100 is a device of a general user using a mobile communication service.

The user terminal 100 may include a GPS receiver and various sensors to generate location information while moving along with the user's movement. The user terminal 100 collects radio wave information of a geomagnetic or radio wave transmitting device such as a wireless LAN access point, a base station, a repeater, a femtocell, BLE, a beacon transmitter, and an ultrasonic transmitter. The radio wave information includes radio wave strength and identification information of the radio wave transmitting device, and may further include the location information. The location information may include location information measured by the GPS receiver, or movement trajectories measured by various sensors such as a magnetic field sensor, an inertial sensor, an atmospheric pressure sensor, and an optical sensor of the various sensors, for example, the user terminal 100 . include information.

The communication network 200 is a medium used to provide a communication link between various devices connected to each other in the system and a data processing system. The communication network 200 may include connections such as wires, wireless communication links, or fiber optic cables. The communication network 200 is a wide area network (WAN), a local area network (LAN), a wireless network of a WAN or LAN, a mobile network, a virtual private network (VPN), the Internet, a general telephone It may be implemented by including or using a Public Switched Telephone Network (PSTN) or similar, different various communication technologies.

The radio wave map construction apparatus 300 builds a radio wave map for each small area within a building and stores it in the database 400 . The database 400 stores a radio wave map using radio wave information collected by professional personnel or robots for a main area, and uses radio wave information collected by the user terminals 100 for the remaining detailed areas other than the main area. A propagation map, that is, a propagation map constructed through crowdsourcing is stored. The radio wave map construction device 300 receives radio wave information on a main area from a radio wave collecting device or robot possessed by a professional manpower, generates a radio wave map using it, and stores it in the database 400 , and for the remaining areas, the user terminal A radio wave map is generated using radio wave information received from the fields 100 and stored in the database 400 . The radio wave information received from the user terminals 100 may include collection position information, and the collection position information may be absolute position coordinates such as GPS position coordinates, or movement trajectory information by dead reckoning, ie, relative position coordinates. have.

A typical example of radio waves in a radio wave map-based positioning system is a Wi-Fi signal, and the radio map is a reference location coordinate (e.g., For example, the coordinates of the center of the region). It is common to separately inject specialized personnel to build a radio wave map according to location, or to perform initial radio map construction using a drivable robot to save time, manpower, and cost. In the case of mobilizing professional manpower, it has the advantage that it is possible to collect radio wave information about spaces that are difficult for a robot to move independently, such as stairs, narrow corridors, elevators, and doors, but it is difficult to check the exact point, so additional errors may occur in the stage of constructing the radio map. It has the disadvantage that it can occur, and the time and cost required for collection are large. On the other hand, when using a robot, it has the advantage of being able to collect radio wave information at an accurate location and has the advantage that it does not require a separate labor cost, but has the disadvantage that the accessible area is limited and additional initial cost is required. In some POI (Point Of Interest) areas that are difficult for outside personnel to enter, it is practically impossible to collect radio wave information by unauthorized personnel and robots. On the other hand, if a radio wave map is constructed using only crowdsourcing, it has the advantage that radio wave information can be collected for all areas where people can enter, but it has the disadvantage that it takes a long time to build a reliable radio map, and it is necessary to set an accurate reference point. It has the disadvantage that an additional technique is required for Therefore, in the embodiment of the present invention, the construction of the radio wave map using a professional manpower or robot minimizes the initial radio map construction area by performing only the main areas where anyone can enter, such as a hallway, and crowd-sourcing for the remaining areas. can reduce the cost and reduce the overall system construction time. When constructing a propagation map through crowdsourcing, the time required for constructing a propagation map through crowdsourcing is reduced by constructing a propagation map by predicting a propagation pattern in an area where a radio map is not established using the area in which the propagation map is built. More specifically, it will be described below with reference to the drawings.

2 is a view showing an indoor view according to an embodiment of the present invention. Referring to FIG. 2 , radio wave information is collected only for indoor corridors through reliable professional personnel or robots. At this time, the location of the radio wave collection of the corridor includes a position perpendicular to the entrance of each room, and is denoted by C _n (n is a natural number) in FIG. 2 , and also the radio wave collection location of the intersection (I _I ). In the case of a hallway without an entrance to a room, radio wave collection may be performed at any location. The location of the radio wave collection in this corridor is defined as a node. A professional man or robot collects radio waves after being located in each node in the main area of the room, that is, a corridor, and transmits radio wave information (signal strength, identification information of radio wave transmitter, absolute position coordinates of each node, etc.) to radio map construction device It can be transmitted to (300). The radio wave map construction apparatus 300 generates a radio wave map using the received radio wave information and stores it in the database 400 . The reason for using a professional manpower or a robot only for the corridor as described above is that anyone can freely move the corridor and the access point is managed by the manager of the building. However, since the rooms other than the corridor are public spaces or physically narrow spaces such as conference rooms, private offices, toilets, etc., professional personnel or robots cannot enter, so the radio wave map construction device 300 is a user who can enter the room. A radio wave map of each room is constructed using radio wave information collected from the user terminals 100 of each other.

In general, in the case of a space such as a hotel, officetel, or office, the interior structure is often similar due to the floor or building structure. Therefore, when the indoor structure of a plurality of rooms is similar and the external physical properties are similar, for example, when the location of the entrance and the propagation patterns of the radio wave transmitting devices collected at each node of the corridor connected thereto are similar, the radio waves detected at each node It can be estimated that the transmitting devices show a similar propagation pattern even in a plurality of rooms having a similar indoor structure. For example, in FIG. 2 , room 'A' and room 'B' have similar internal structures, ie, size and shape. And, the arrangement position of the entrance is also similar, and in addition, when the propagation patterns of the radio wave transmitting devices collected in each of the nodes C ₁ and C ₃ of the corridor, for example, the pattern of signal strength are similar, the 'A' room and the 'B' room It can be estimated that the propagation patterns of the corresponding radio transmission devices are similar in each interior. For example, the radio wave from 'AP1' at node C ₁ of the hallway leading to the doorway of room 'A' shows a signal strength of -50 dBm, and the radio wave from the corresponding 'AP1' inside room 'A' has a signal of -70 dBm If the radio wave of 'AP3' from node C ₃ of the hallway connected to the doorway of room 'B' shows a signal strength of -50 dBm, the radio wave of 'AP3' inside the room 'B' is -70 dBm It can be inferred that it has signal strength. That is, if there are a plurality of rooms having similarity, and the propagation pattern of the node of the corridor connected to the entrance and exit of each room is similar, the propagation pattern of radio wave transmitters detected in the node of the corridor in each room, that is, the pattern of signal strength can also be considered similar. Here, the similarity may mean that the signal strength falls within a threshold range. Therefore, when the radio wave map of room 'A' is built, the radio wave map of room 'B' can be quickly constructed using the radio map of room 'A'. On the other hand, room 'A' and room 'C' have similar internal structures, i.e., size and shape, but because the location of the entrance, which is one of the external physical characteristics, is different, the correlation between the two rooms is low. ' It is difficult to directly reflect in the room.

3 is a diagram illustrating the configuration of an apparatus for constructing a radio wave map according to an embodiment of the present invention.

The propagation map building apparatus 300 shown in FIG. 3 may include a memory, a memory controller, one or more processors (CPU), a peripheral interface, an input/output (I/O) subsystem, a display device, an input device, and a communication circuit. have. These components communicate via one or more communication buses or signal lines. These various components may be implemented in hardware, software, or a combination of both hardware and software, including one or more signal processing and/or application specific integrated circuits.

The memory may include high-speed random access memory, and may also include one or more magnetic disk storage devices, non-volatile memories such as flash memory devices, or other non-volatile semiconductor memory devices. Access to memory by other components, such as processors and peripheral interfaces, may be controlled by the memory controller.

Peripheral interfaces connect I/O peripherals to the processor and memory. One or more processors execute various software programs and/or sets of instructions stored in memory to perform various functions for the system and process data. In some embodiments, the software component is loaded with (installed) an operating system, a graphics module (instruction set), and a program for performing operations for the present invention. The operating system may be, for example, a built-in operating system such as Darwin, RTXC, LINUX, UNIX, OS X, WINDOWS or VxWorks, Android, iOS, etc., and performs general system tasks (eg, memory management). , storage device control, power management, etc.) to control and manage various software components and/or devices, and facilitate communication between the various hardware and software components. The graphics module includes several well-known software components for providing and displaying graphics on a display device. The term "graphics" includes any object that can be displayed, including without limitation text, web pages, icons (eg, user interface objects including soft keys), digital images, video, animations, and the like. . In some embodiments, the peripheral interface, processor, and memory controller may be implemented on a single chip, such as a chip. In some other embodiments, they may be implemented as separate chips.

The I/O subsystem provides an interface between the input/output peripherals of devices such as display devices and input devices and the peripheral interfaces. The display device may use a liquid crystal display (LCD) technology or a light emitting polymer display (LPD) technology, and the display device may be a touch display such as a capacitive type, a resistive type, or an infrared type. The touch display provides an output interface and an input interface between the system and the user. The touch display presents a visual output to the user. The visual output may include text, graphics, video, and combinations thereof. Some or all of the visual output may correspond to a user interface object. The touch display forms a touch-sensitive surface that receives user input. A processor is a processor configured to perform an operation associated with a system and perform instructions, for example, using instructions retrieved from a memory, to control reception and manipulation of input and output data between components of the system.

Communication circuitry may include Ethernet communication circuitry and RF circuitry. The Ethernet communication circuit performs wired communication, and the RF circuit transmits and receives electromagnetic waves. RF circuitry converts electrical signals into electromagnetic waves and vice versa and communicates with communications networks, other mobile gateways, and communications devices via the electromagnetic waves. RF circuitry may include well-known circuitry for performing these functions including, but not limited to, for example, an antenna system, an RF transceiver, one or more amplifiers, a tuner, one or more oscillators, a digital signal processor, a CODEC chipset, a memory, and the like. can The RF circuitry may communicate with other devices by means of cellular telephone networks, wireless networks such as wireless LANs and/or metropolitan area networks (MANs), and short-range wireless communications.

Referring to FIG. 3 , the radio wave map construction apparatus 300 includes a first construction module 301 , an analysis module 302 , and a second construction module 303 . These components may be manufactured as a program, stored in a memory, and operated by a processor, or may be manufactured as a combination of software and hardware.

The first building module 301 receives radio wave information collected from each node in a main area of the room, for example, a corridor by a professional person or a robot. The first building module 301 may directly receive radio wave information from a radio wave collecting device or robot of a professional manpower through the communication network 200, or may receive radio wave information through a USB memory or the like. The first building module 301 extracts the location of the node, that is, the collection location, the identification information of the radio wave transmitting device, the signal strength of the radio wave, etc. from the radio wave information received in this way, and generates a radio wave map and stores it in the database 400 . Save.

The analysis module 302 builds the propagation map by the first building module 301 using the node included in the indoor drawing stored in the database 400 and the propagation map generated by the first building module 301 . Areas that have not been constructed, that is, areas subject to crowdsourcing propagation map construction, are classified into similar areas. Referring to FIG. 2 , rooms A to G may be first classified into groups [A, B, C, D, E], [F, H], and [G] according to internal structures. In addition, each group can be secondarily classified according to external physical characteristics based on the corridor node. Based on corridor I, the [A, B, C, D, E] group can be secondarily classified into [A, B] and [C, E]. In [A, B], the location of the entrance and the location of the node of the corridor connected to it are similar. The same goes for [C, E]. The criterion of similarity may mean that the location exists within a certain range. However, D is not included in the [C, E] group because the location of the door and the node of the corridor connected to it are similar to those of C and E, but the location of the node of the corridor is located within a certain distance from the intersection node. This is because the intersection affects the propagation pattern. [F, H] are classified into different areas because the location of the entrance to the room connected to the corridor node is different. On the other hand, if no nodes are displayed in corridor II of FIG. 2 but there are nodes along the center of corridor II, A to G are all classified into different regions based on corridor II. This is because the distances from the nodes in corridor II are all different. If D is directly adjacent to hallway Ⅱ like C, and if the location of the door of D is symmetrical to C with respect to hallway Ⅱ, then C and D may have similar distances from the node in hallway Ⅱ, so For the node in II, it can be secondarily classified into a similar area.

The second building module 303 constructs a propagation map in a crowdsourced manner for areas where the propagation map is not built in the first building module 301 . The second building module 303 receives the radio wave information collected in the corresponding area from the user terminals 100 located in the radio map non-established area. Here, the radio wave information includes identification information of the radio wave transmitting device, signal strength of radio waves, and may further include location information. The second construction module 303 generates a radio wave map for an area in which a radio wave map is not constructed by using radio wave information received from the user terminals 100 , and stores it in the database 400 . For example, the second construction module 303 extracts identification information and radio signal strength of each radio transmission device from radio information received from the plurality of user terminals 100 that have entered the radio map non-establishment area, The average value of the radio signal strengths of each radio wave transmitting device is matched with the identification information of the radio wave transmitting device, and the location (eg, the central location of the room) of the non-established area of the radio wave map and stored in the database 400 .

The second building module 303 may determine that the user terminals 100 enter the radio wave map non-established area using GPS location information (eg, indoor GPS location information) received from the user terminals 100 . have. Alternatively, it can be identified using the propagation map of the main area built by the first building module 301 and stored in the database 400 and movement trajectory information measured by the sensor received from the user terminals 100 . For example, the second building module 303 may use the radio wave information received from the user terminals 100 to specify the last position in the corridor of the user terminal 100 in the radio wave map stored in the database 400 . can For example, using pattern information such as identification information of a radio wave transmitting device and radio signal strength included in the radio wave information, a matching area is identified on the radio map, and the representative location of the area, that is, the node's location, is set to the last location in the hallway. can judge Then, the second building module 303 may determine the user's entry into the non-established radio wave map area according to the movement trajectory information (whether left or right rotation, the number of steps, etc.) measured by the sensor received from the user terminal 100 . have.

The second building module 303, when constructing a propagation map of an area in which a radio map has not been established in the crowdsourcing method, based on each node of the corridor analyzed by the analysis module 302, compares the similarity and By using the propagation map of each node in the corridor, the propagation map construction of the area where the propagation map has not been established is quickly completed. When there are a plurality of non-established radio map regions having similarity with respect to the node of the corridor, and the propagation pattern of the nodes of the corridor, which is the similarity criterion of the regions, is similar, each radio wave map of the radio wave transmitting devices detected by the nodes of the corridor The propagation pattern inside the unconstructed area is also similar. For example, in FIG. 2 , room 'A' and room 'B' have similar internal structures, that is, size and shape, and the arrangement position of the doorway based on the nodes C ₁ and C ₃ of the hallway connected to the doorway. similar. In addition, if the propagation patterns of radio wave transmitting devices collected by professional personnel or robots at each of the nodes C ₁ and C ₃ of the corridor, for example, the pattern of signal strength are similar, the nodes C 1 and C 3 of the corridor were detected at each of the nodes C ₁ and C ₃ It can be assumed that the radio wave transmitting devices show a similar propagation pattern inside each of the 'A' and 'B' rooms. For example, the radio wave from 'AP1' at node C ₁ in the hallway leading to the doorway of room 'A' shows a signal strength of -50 dBm, and the radio wave from the corresponding 'AP1' inside room 'A' has a signal of -70 dBm If the radio wave of 'AP3' from node C ₃ of the hallway connected to the doorway of room 'B' shows a signal strength of -50 dBm, the radio wave of 'AP3' inside the room 'B' is -70 dBm. It can be assumed that the signal strength has Accordingly, if the propagation map for room 'A' is built, the second building module 303 is configured to configure the propagation pattern of the radio wave transmitting device detected at node C ₁ of the hallway among the propagation patterns of the propagation map of room 'A', for example, While applying the signal strength pattern to room 'B' as it is, the identification information of the radio wave transmitting device (identification information of AP1) is changed only to the identification information of the radio transmitting device (identification information of AP3) detected at node C ₃ in the hallway . In this way, when a propagation map is constructed in the crowdsourcing method for any one of the areas to be constructed of the crowdsourced propagation map, the second building module 303 applies the propagation pattern of this area to an area similar to this area to create a crowd The propagation map of the sourcing propagation map construction target areas is quickly completed.

4 is a flowchart illustrating a method of constructing a propagation map according to an embodiment of the present invention.

Referring to FIG. 4 , the radio wave map construction apparatus 300 generates a radio wave map based on a plurality of nodes for a main area within a building and stores it in the database 400 ( S401 ). Here, the main area may mean an indoor hallway. And, a node is a location where radio wave information is collected by a professional manpower or a robot, and means a point on the hallway. Preferably, when there are doorways of the rooms in the hallway, a central part of the hallway perpendicular to the door is designated as a node, and also designated as a roadway at an intersection. Any other point in the hallway can be designated as a node. The radio wave map construction apparatus 300 receives radio wave information collected from nodes in a main area from a radio wave collecting device or robot possessed by a professional manpower, generates a radio wave map using the radio wave information, and stores the generated radio wave map in the database 400 . The radio wave map may include location information of a node that is a collection location, identification information of the collected radio transmission device, and signal strength. The radio wave map construction apparatus 300 may directly receive radio wave information from a radio wave collecting device or a robot of a professional manpower through the communication network 200 , or may receive radio wave information through a USB memory or the like.

When the propagation map for the main area is generated in step S401, the propagation map construction apparatus 300 classifies the remaining detailed areas except for the main area in the room into areas corresponding to each other (S403). The propagation map construction apparatus 300 classifies the plurality of detailed regions into regions corresponding to each other based on the internal structure and external physical characteristics based on the nodes specified in step S401. Referring to FIG. 2 , rooms A to G may be first classified into groups [A, B, C, D, E], [F, H], and [G] according to internal structures. In addition, each group can be secondarily classified according to external physical characteristics based on the corridor node. Based on corridor I, the [A, B, C, D, E] group can be secondarily classified into [A, B] and [C, E]. In [A, B], the location of the entrance and the location of the node of the corridor connected to it are similar. The same goes for [C, E]. The criterion of similarity may mean that the location exists within a certain range. However, D is not included in the [C, E] group because the location of the door and the node of the corridor connected to it are similar to those of C and E, but the location of the node of the corridor is located within a certain distance from the intersection node. This is because the intersection affects the propagation pattern. [F, H] are classified into different areas because the location of the entrance to the room connected to the corridor node is different. On the other hand, if no nodes are displayed in corridor II of FIG. 2 but there are nodes along the center of corridor II, A to G are all classified into different regions based on corridor II. This is because the distances from the nodes in corridor II are all different. If D is directly adjacent to corridor Ⅱ like C, and if the position of the door of D is symmetrical with respect to corridor Ⅱ, then C and D may have similar distances from the node in corridor Ⅱ, so It can be secondarily classified into similar regions for nodes with

After classifying the detailed regions into regions corresponding to each other as described above, the propagation map construction apparatus 300 generates and stores a propagation map for any one of the regions corresponding to each other ( S405 ). Specifically, the radio wave map construction apparatus 300 receives radio wave information collected in the corresponding area from the user terminals 100 located in the one area. Here, the radio wave information includes identification information of the radio wave transmitting device, signal strength of radio waves, and may further include location information. The radio wave map construction apparatus 300 generates a radio wave map using radio wave information received from the user terminals 100 and stores it in the database 400 . For example, the identification information and radio signal strength of each radio wave transmitting device are extracted from the radio wave information, and the average value of radio signal strengths of each radio wave transmitting device, the identification information of the radio wave transmitting device, and the location of the corresponding area (e.g., the location of the room) center position) is matched and stored in the database 400 . The radio map construction apparatus 300 may determine that the user terminals 100 enter the radio map non-established area using GPS location information (eg, indoor GPS location information) received from the user terminals 100 . have. Alternatively, it may be determined using a radio wave map of a main area constructed by the radio wave map construction apparatus 300 and stored in the database 400 and movement trajectory information measured by a sensor received from the user terminals 100 . For example, the last position in the hallway of the user terminal 100 may be specified from the radio wave map stored in the database 400 using radio wave information received from the user terminals 100 . For example, using pattern information such as identification information of a radio wave transmitting device and radio signal strength included in the radio wave information, a matching area is identified on the radio map, and the representative location of the area, that is, the node's location, is set to the last location in the hallway. can judge Then, it is possible to determine whether the user enters an area where the radio wave map is not established according to movement trajectory information (whether left or right rotation, number of steps, etc.) measured by the sensor received from the user terminal 100 .

Next, the propagation map construction apparatus 300 generates a propagation map of the remaining areas among the areas corresponding to each other by using the propagation map of one area and stores it in the database 400 ( S407 ). For example, referring to FIG. 2 , the radio wave of 'AP1' at node C ₁ of the hallway connected to the doorway of room 'A' shows a signal strength of -50 dBm, and the radio wave of the corresponding 'AP1' inside room 'A' represents a signal strength of -70 dBm, and if the radio wave of 'AP3' at node C ₃ of the hallway connected to the doorway of room 'B' shows a signal strength of -50 dBm, The radio wave can be estimated to have a signal strength of -70 dBm. Accordingly, the propagation map construction apparatus 300 applies the propagation pattern of the radio wave transmitting device detected at node C ₁ of the hallway among the propagation patterns of the propagation map of the room 'A', for example, the signal strength pattern to the room 'B' as it is, Only the identification information of the radio wave transmitting device (identification information of AP1) is changed to the radio wave transmitting device identification information (identification information of AP3) detected at node C ₃ of the corridor.

The propagation map construction apparatus 300 checks whether the generation of the propagation map for all the detailed regions is completed (S409), and if not, repeats the above-described step S405 for other regions corresponding to each other to create all the detailed regions. Complete the propagation map for

While this specification contains many features, such features should not be construed as limiting the scope of the invention or the claims. Also, features described in individual embodiments herein may be implemented in combination in a single embodiment. Conversely, various features described herein in a single embodiment may be implemented in various embodiments individually, or may be implemented in appropriate combination.

Although acts are described in a particular order in the drawings, it should not be understood that the acts are performed in the particular order as shown, or that all of the described acts are performed in a continuous order, or to obtain a desired result. . Multitasking and parallel processing can be advantageous in certain circumstances. In addition, it should be understood that the division of various system components in the above-described embodiments does not require such division in all embodiments. The program components and systems described above may generally be implemented as a package in a single software product or multiple software products.

The method of the present invention as described above may be implemented as a program and stored in a computer-readable form in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.). Since this process can be easily performed by a person skilled in the art to which the present invention pertains, it will not be described in detail any longer.

The present invention described above, for those of ordinary skill in the art to which the present invention pertains, various substitutions, modifications and changes are possible within the scope without departing from the technical spirit of the present invention. It is not limited by the drawings.

100: user terminal
200: communication network
300: radio map building device
400 : database
301: first building module
302: analysis module
303: second building module

Claims (14)

An apparatus for constructing a radio wave map for a main area and a plurality of detailed areas, the apparatus comprising:
a storage unit for storing a radio wave map for each area;
a first construction module for generating a propagation map based on a plurality of nodes for the main area and storing the generated propagation map in the storage unit;
an analysis module for classifying the plurality of detailed regions into regions corresponding to each other based on an internal structure and external physical characteristics based on the plurality of nodes; and
Among the regions corresponding to each other, a propagation map is generated for any one region for regions corresponding to a propagation pattern of a node, and a propagation map of the remaining regions is generated using the propagation pattern of the propagation map of the corresponding region and stored. A radio wave map building apparatus comprising a second building module for storing in the unit. The method of claim 1,
The analysis module,
An apparatus for constructing a radio wave map for classifying regions in which internal structures including internal shapes and sizes correspond to each other, and external physical properties including positions of external nodes with respect to the position of an entrance and exit correspond to each other. 3. The method of claim 2,
Regions to which the propagation pattern of the node corresponds are,
A propagation map construction apparatus in which propagation patterns in external nodes that are at the same distance from the entrance and vertically connected from the entrance correspond to each other. 4. The method of claim 3,
The external node vertically connected from the entrance is spaced apart from the intersection node by a predetermined distance or more. 3. The method of claim 2,
The propagation pattern is a propagation map construction apparatus including a pattern of signal strength. The method of claim 1,
The analysis module,
An apparatus for constructing a radio wave map that classifies regions in which the internal structure including the internal shape and size and the location of the doorway are symmetric to each other based on a node, into regions corresponding to each other. The method of claim 1,
The second building module,
By receiving radio wave information from one or more user terminals that have collected radio wave information in each of the remaining areas, and combining the identification information of a radio wave transmitting device extracted from the received radio wave information with the propagation pattern of the one area, the propagation of the remaining areas A radio map builder that generates maps. A method of constructing a radio map for a main area and a plurality of detailed areas in a radio map construction apparatus, the method comprising:
a first construction step of generating a propagation map based on a plurality of nodes for the main area and storing it in a storage unit;
classifying the plurality of detailed regions into regions corresponding to each other based on an internal structure and external physical characteristics based on the plurality of nodes; and
Among the regions corresponding to each other, a propagation map is generated for any one region for regions corresponding to a propagation pattern of a node, and a propagation map of the remaining regions is generated using the propagation pattern of the propagation map of the corresponding region and stored. and a second building step of storing to the wealth. 9. The method of claim 8,
The classification step is
A method of classifying regions in which internal structures including internal shapes and sizes correspond to each other, and external physical properties including external node positions with respect to the position of the entrance and exit correspond to each other. 10. The method of claim 9,
Regions to which the propagation pattern of the node corresponds are,
A method in which propagation patterns in external nodes that are the same distance from the doorway and are vertically connected from the doorway correspond to each other. 11. The method of claim 10,
The external node vertically connected from the entrance is spaced apart from the intersection node by a predetermined distance or more. 10. The method of claim 9,
The propagation pattern includes a pattern of signal strength. 9. The method of claim 8,
The classification step is
A method of classifying regions in which the internal structure including the internal shape and size and the position of the doorway are symmetrical with respect to one node into regions corresponding to each other. 9. The method of claim 8,
The second construction step is,
By receiving radio wave information from one or more user terminals that have collected radio wave information in each of the remaining areas, and combining the identification information of a radio wave transmitting device extracted from the received radio wave information with the propagation pattern of the one area, the propagation of the remaining areas How to create a map.

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