KR102260936B1 - Indoor localization method and system - Google Patents

Abstract

The present invention relates to a method and a system for indoor positioning. An indoor positioning method according to the present invention, includes the steps of: receiving, by a mobile device, a wireless signal from a plurality of APs installed at least one or more on each floor of a building; performing exponentiation of signal strength using the signal strength and a threshold value of the received wireless signal; and using the received wireless signal to detect floor information of the AP which has transmitted the wireless signal, reflecting floor information to indexed signal strength to apply weight, and performing positioning on the floor of the mobile device using a weighted result value. Therefore, it is possible to implement simple yet high-accuracy indoor positioning.

Description

INDOOR LOCALIZATION METHOD AND SYSTEM

The present invention relates to a method and system for indoor positioning in a multi-story building environment.

Recently, with the advancement of technologies such as mobile devices and networks, a location-based service (LBS) that provides specific information according to a changed location to a user has been developed.

The technologies for realizing location-based services have been mainly developed around outdoor spaces, but research and development are also focused on technologies that implement various convergence-based services in indoor spaces, centering on high-rise buildings in downtown areas.

With this research and development, indoor positioning technology, RF (Radio Frequency) and UWB (Ultra-Wide Band) positioning, inertial measurement-based positioning, RFID (Radio Frequency Identification)-based positioning, Floor Sensor-based positioning, magnetic system-based positioning, optical Various technologies such as system-based positioning have been proposed.

On the other hand, in the case of high-rise buildings, location information must be accurately estimated in a multi-story three-dimensional building environment, and indoor positioning is difficult only with location information of two-dimensional planar coordinates.

Therefore, it is very important to accurately determine the number of floors of a building in which a user is located for indoor positioning within a building. In other words, if a user can know which floor he is on in which building, various location-based services are possible from that.

In addition, even when a map and a model are used for more sophisticated indoor positioning, data transmission/reception burden can be reduced if building and floor information can be easily known as initial location information of a user.

Among the various indoor positioning techniques described above, a positioning technique based on Received Signal Strength Indication (RSSI) is very useful in positioning to classify floors. As an example, Korean Patent Registration No. 10-1508312 (announced on April 07, 2015) proposes a method for predicting the signal strength of another layer using a loss index, and finally selecting a layer with a small variance, have. However, this method involves a process of predicting a signal by applying a loss index to an adjacent floor, but it is difficult to apply when the building is different.

Therefore, by applying a new approach, an indoor positioning method that can classify floors even in different buildings can be proposed.

The present invention is to provide an indoor positioning method and system applicable to various buildings.

More specifically, the present invention provides an indoor positioning method and system capable of classifying floors including all buildings in a search range by using signal strength even if the buildings are different.

In order to solve the above problems, the indoor positioning method and system according to the present invention uses a process of indexing only the signal strength itself based on the threshold value and utilizing the same.

Specifically, the indoor positioning method includes receiving, by a mobile device, a wireless signal from a plurality of APs installed at least one or more on each floor of a building, and using the signal strength and threshold value of the received wireless signal, the signal strength performing an indexing for , and using the received radio signal, detecting the layer information of the AP that has transmitted the wireless signal, reflecting the layer information to the indexed signal strength and assigning a weight, and the and performing positioning on the floor of the mobile device by using the weighted result value.

Furthermore, in the present invention, in the step of performing the exponentiation, the exponentiation may be performed using the difference between the signal strength and the threshold value so that the signal having the high signal strength has a large number based on the threshold value.

The indoor positioning method may include selecting a dominant signal having the signal strength equal to or greater than the threshold value, and adjusting the threshold value when the dominant signal is not selected.

The adjusting of the threshold may select the dominant signal while lowering the threshold from the initial threshold to a preset level.

In addition, the indoor positioning method may include the mobile device collecting building information from APs installed in different buildings, and determining a target building for positioning the floor of the mobile device.

In the step of determining the target building, indexing is performed on the signal strength using the signal strength of a signal including the building information and a threshold value for building positioning, and the building information is reflected in the indexed signal strength. A weight is given, and the target building is determined using the weighted result value. In this case, the threshold value may be set to the same value as the threshold value for positioning the building. A wireless signal received from an AP of a building different from the target building may be filtered when positioning the floor of the mobile device. have.

Furthermore, the mobile device may request a DB corresponding to the floor on which the mobile device is located, determined by performing positioning on the floor, from the server.

In addition, the indoor positioning method may include detecting a movement between floors of the mobile device, and when the movement between floors is detected, positioning of the floor of the mobile device may be performed.

In addition, the present invention comprises the steps of: a mobile device receiving a wireless signal from a plurality of APs; detecting building information of an AP that has transmitted the wireless signal using the wireless signal; Exponentiation of the signal strength using a threshold value, detecting a building using the indexed signal strength and the building information, and floor information of an AP that transmits the wireless signal using the wireless signal Disclosed is an indoor positioning method comprising the steps of detecting, and performing positioning on the floor of the mobile device based on the detected building, using the indexed signal strength and the floor information.

Furthermore, the present invention provides a database for storing at least one of building information and floor information together with the MAC address of the AP as data, and a calculation unit for positioning a floor on which a mobile device receiving a wireless signal from the AP is located. Including, wherein the calculating unit, performing the exponentialization of the signal strength using the signal strength and the threshold value of the wireless signal, and detecting the layer information of the AP that has transmitted the wireless signal, the layer information Disclosed is an indoor positioning system that assigns weights by reflecting the indexed signal strength, and performs positioning on the floor of the mobile device using the weighted result value.

The indoor positioning method and system according to the present invention uses a unique ID (MAC) and signal strength (RSSI) of wireless communication equipment to recognize the floor information on which a user is located, and through this, a simpler and more accurate indoor positioning to implement

In addition, the present invention uses a method of indexing the signal strength based on a threshold value and changing it to a weight, so that it is possible to classify floors including all buildings in the search range. In this way, even if the buildings are different, only the signal strength itself is indexed based on the threshold value, and by using this, an indoor positioning method suitable for a complex urban environment can be implemented.

In addition, the present invention compensates for the low accuracy when determining the location by calculating and averaging the layer information of the selected AP, so that a more accurate result can be derived by using the signal strength as a weight.

In addition, according to the present invention, after the building is divided, as the location is performed on the floor, accurate indoor positioning is performed even if a signal from a building other than the corresponding building is received.

1A and 1B are conceptual views for explaining a method for performing indoor positioning according to the present invention.
2 is a block diagram for explaining the outline of a positioning system according to the present invention.
3 is a flowchart representatively illustrating an indoor positioning method according to the present invention.
4 is an exemplary view for explaining the indoor positioning method of FIG. 3 in detail.
5 is a flowchart representatively illustrating an indoor positioning method according to another embodiment of the present invention.
6 is an exemplary view for explaining the indoor positioning method of FIG. 5 in detail.
7 is a conceptual diagram illustrating another embodiment of an indoor positioning method and system according to the present invention.

Hereinafter, the embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but the same or similar components will be given the same reference numbers regardless of reference numerals, and redundant descriptions thereof will be omitted. The suffixes "module" and "part" for the components used in the following description are given or mixed in consideration of only the ease of writing the specification, and do not have distinct meanings or roles by themselves. In addition, in describing the embodiments disclosed in the present specification, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in this specification, the detailed description thereof will be omitted. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed herein is not limited by the accompanying drawings, and all changes included in the spirit and scope of the present invention , should be understood to include equivalents or substitutes.

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

When a component is referred to as being “connected” or “connected” to another component, it is understood that the other component may be directly connected or connected to the other component, but other components may exist in between. it should be On the other hand, when it is mentioned that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present application, terms such as "comprises" or "have" are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

The present invention relates to a method and system for indoor positioning in a multi-story building environment, and specifically to provide an indoor positioning method and system for performing positioning on a floor.

Here, positioning is to determine a location or to obtain information about the location, and it may be a technique for determining the exact location of the service request terminal by using the location of a base station of a GPS or a wireless network, or by using various sensor information. . Here, the exact position may exist in various forms, such as an absolute position, a relative position, a conceptual position, and the like. In particular, in the positioning of the present invention, indoor positioning technology for acquiring a location indoors that does not receive a GPS signal may be applied. In this case, various methods such as detecting a zone in which the mobile device is located or detecting a real-time location of the mobile device may be applied. In addition, the positioning of the present invention may be referred to as localization (Localization), location determination (Location Determination), or positioning (Positioning) or the like.

In addition, in the present specification, a mobile device is used as a term that includes both a mobile terminal that can be held in a hand or can be conveniently carried on the body, and a mobile device that can be moved by itself.

For example, the mobile terminal includes a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, and a slate PC. , a tablet PC, an ultrabook, a wearable device, for example, a watch-type terminal (smartwatch), a glass-type terminal (smart glass), a head mounted display (HMD), etc. may be included. As another example, the mobile device may be a robot that provides a location-based service while moving, such as a cleaning robot, a guide robot, and a delivery robot.

Meanwhile, in an embodiment of the present invention, a new indoor positioning method and system for acquiring building and floor information will be described based on the location of the mobile device, but the present invention is not necessarily limited thereto. The mobile device is understood as one means of measuring the user's location, and other devices may also be applied to the present invention.

As such, the indoor positioning method and system according to the present invention obtains building and floor information as initial location information of the user to provide various location-based services therefrom after recognizing which floor the user is on. Hereinafter, the indoor positioning method and system of the present invention will be described in more detail with reference to the drawings.

1A and 1B are conceptual diagrams for explaining a method of providing a location-based service by performing indoor positioning according to the present invention.

1A and 1B illustrate a case in which a DB for a Wi-Fi positioning system (WPS) is stored separately for each layer.

As shown in FIG. 1A , when a user is located in any one of the buildings 11 in an environment in which a plurality of buildings 11, 12, 13, and 14 are dense, the corresponding building is provided to the user by using the DB for WPS. A location-based service suitable for

For example, a user may have a mobile device 120 , and the mobile device 120 may be implemented in the form of a communication terminal capable of various types of wireless communication, such as a smart phone or a tablet PC.

In this case, the mobile device 120 is configured to provide a location-based service to the user, and for this purpose, an application related to the location-based service may be stored in the mobile device 120 . The application executes the service corresponding to the floor by using the floor information on which the user is located.

Referring to FIG. 1B , the building 11 has multiple floors, and one or more APs may be installed on each floor.

The AP (Access Point) refers to a low-power wireless device serving as a base station in a wireless LAN, and serves as a bridge connecting wired and wireless devices. More specifically, the AP functions to connect the mobile device 100 using wireless communication to a network. As described above, in the present specification, the AP is a relay facility between a network and a user, and may be a wireless communication device. However, the present invention is not necessarily limited thereto, and the AP may refer to a place where a relay facility is installed.

In the environment of FIG. 1B , the user's mobile device 120 detects the floor on which the mobile device 120 is located using the unique ID (MAC) and signal strength (RSSI) of the searched wireless communication equipment. In this way, after finding the floor in which the user is located first, WPS is performed using the DB of the corresponding floor to find the exact location of the user.

The mobile device 120 may request a DB corresponding to the floor on which the mobile device 120 is located, determined by performing positioning on the floor, from the server. As a specific example, as shown, the application receives the DB corresponding to the floor where the mobile device 120 is located, and provides various location-based services using the DB.

In order to implement a location-based service through indoor positioning, illustrated with reference to FIGS. 1A and 1B above, the present invention proposes a new method and system for indoor positioning that simply and with high accuracy identifies a floor.

As described above, the present invention provides a new indoor positioning methodology for recognizing which floor of a building a user is located on. Hereinafter, together with the accompanying drawings, the indoor positioning method and system according to the present invention are more Let's look at it in detail. 2 is a block diagram for explaining the outline of a positioning system according to the present invention, FIG. 3 is a flowchart representatively illustrating an indoor positioning method according to the present invention, and FIG. 4 is a detailed description of the indoor positioning method of FIG. It is an example diagram for

In the following description, “a method and a system for determining the location of one mobile device” will be described as an example, but it goes without saying that the present invention can be commonly used for a plurality of mobile devices.

First, referring to FIG. 2 , the indoor positioning system 100 according to the present invention may include a DB management unit 110 , a mobile device 120 , and an operation unit 130 .

The DB management unit 110 includes a database 111, and the database 111 (DB) may store layer information together with the MAC address of the AP as data. For example, the DB management unit 110 may manage information in which [AP MAC address, layer information] are paired as a DB.

However, the present invention is not necessarily limited thereto, and the DB may be a database that stores at least one of building information and floor information as data together with MAC addresses of APs (AP1, AP2, ... APN). In this case, the DB management unit 110 may manage the paired information of [AP MAC address, building information, floor information] as a DB. In this way, at least one of the building information and the floor information may be stored as data together with the MAC addresses of the APs (AP1, AP2, ... APN).

In this case, the MAC address of the AP (AP1, AP2, ... APN) may be a unique ID of the wireless communication equipment corresponding to the AP (AP1, AP2, ... APN). Also, the building information (building_num) may be set information for assigning a number to a building, such as assigning 1 to building A and assigning 2 to building B. In addition, the floor information (Floor_num) is an integer-type ID for distinguishing the floors of the building, and the three-story building A may be given a number of 1 (1st floor), 2 (2nd floor), and 3 (3rd floor).

In this case, different buildings may be assigned different types of numbers in order to distinguish them from building A. For example, building B is given a number of 10 (1st floor), 11 (2nd floor), 12 (3rd floor), and 13 (4th floor) by adding an integer (10) to distinguish the building. can be

The mobile device 120 receives a wireless signal from the AP (AP1, AP2, ... APN) through the wireless communication unit 121 . The wireless communication unit 121 may include a wireless Internet module, a short-range communication module, a location information module, and the like.

The control unit 122 of the mobile device 120 uses the wireless communication unit 121 to scan a signal to obtain MAC addresses and signal strength (RSSI) information of the APs (AP1, AP2, ... APN) through this. do.

The operation unit 130 is configured to position the floor on which the mobile device 120 receiving the wireless signal from the APs (AP1, AP2, ... APN) is located.

The calculation unit 130 performs an operation for detecting an actual building name or floor using the DB. More specifically, a lookup table that matches floor information (eg, number 11) and an actual floor (eg, the first floor of building A, or the first floor without a specific building) may be stored in the DB. Furthermore, a lookup table that matches building information (eg, number 1) and an actual building name (eg, A) may be further stored in the DB. The calculation unit 130 refers to the lookup table stored in the DB, and calculates building information and/or floor information by calculation according to examples to be described below, and through this, the calculated building information and/or floor information It is possible to detect an actual building name and/or floor corresponding to .

In this example, the calculating unit 130 is provided separately from the mobile device 120 , but the present invention is not necessarily limited thereto. The calculator 130 may be provided in the mobile device 120 .

The operation unit 130 may perform the steps of performing the indexing and the steps of positioning the layer. The performing of the exponentiation may be a step of performing the exponentiation of the signal strength using the signal strength and a threshold value of the radio signal. In addition, the step of performing the positioning for the layer detects the layer information of the AP that has transmitted the wireless signal, reflects the layer information to the indexed signal strength to give a weight, and the weighted result value It may be a step of performing positioning on the floor of the mobile device by using it. Details of each of these steps will be described later.

In addition, the calculation unit 130 may be configured to perform a primary calculation for classifying a building before positioning the floor. After the first operation, a second operation may be performed for the purpose of classifying layers.

The operation unit 130 may select an AP-pair, [MAC, RSSI] whose signal strength is equal to or greater than a threshold in order to select a dominant signal. In this case, if the dominant signal is not selected, the threshold may be updated. After that, the indexing of the signal strength is performed, and a building or a floor is determined by calculating by applying a weight.

As described above, in the indoor positioning system of the present invention, the DB management unit 110, the mobile device 120, and the calculating unit 130 are combined with each other to recognize the floor where the user is located. will be described in more detail.

Referring to FIG. 3 , the indoor positioning method of the present invention may include a signal receiving step ( S110 ), an indexing step ( S120 ), a weight calculation performing step ( S130 ), and a current position detecting step ( S140 ).

First, in the signal receiving step (S110), the mobile device receives a wireless signal from a plurality of APs installed at least one or more on each floor of a building.

At least one of the plurality of APs is installed on each floor, but the present invention is not limited thereto. That is, if necessary, there may be a floor on which the AP is not installed.

The wireless communication unit of the mobile device receives, for example, a signal including an ID and corresponding floor information from a plurality of APs using a Wi-Fi signal.

More specifically, the user's mobile device receives the unique ID (MAC) and signal strength (RSSI) of the wireless communication equipment, and the above-described operation unit or the control unit of the mobile device uses the database of the above-described DB management unit to obtain the unique ID (MAC) and signal strength (RSSI). The information on the corresponding floor of the building mapped to the ID is extracted.

Referring to FIG. 4 , the DB manager collects layer information of the corresponding AP by using paired information [MAC address of AP, layer information]. For example, like [AA:BB:CC:aa:bb:00, 1], an AP having a MAC address of AA:BB:CC:aa:bb:00 may be an AP located on the first floor.

Also, the calculator 130 may specify a building in which the mobile device 120 is located from the floor information. For example, a building may be specified from a number range to which the floor information belongs. More specifically, if the floor information of a specific building (A) is specified in units of work (a number between 1 and 9), the wireless signal of the AP with the MAC address of AA:BB:CC:aa:bb:00 is When detected, the operation unit 130 allows the mobile device to convert the building “A” corresponding to the number range to which the floor information “1” mapped to the MAC address “AA:BB:CC:aa:bb:00” of the corresponding signal belongs. It can be recognized by the building where Or, when a lookup table that matches both the building and the floor for each floor information value (for example, all numbers between 1 and 9) is stored in the DB, the calculation unit uses the information matching the floor information “1” of the detected signal as “ Building A” and “1st floor” information can also be obtained simultaneously from the lookup table.

In conclusion, when detecting the wireless signal of the AP having the MAC address of AA:BB:CC:aa:bb:00, the operation unit 130 can recognize that the corresponding signal is a signal transmitted from the AP on the first floor of the building A. have.

As a specific example, referring to FIG. 4 , since the wireless signal collected by the mobile device has information of [AP MAC address, RSSI], for example, AA:BB:CC:aa:bb:00 as the MAC address AP is located on the first floor of Building A, and the signal strength is -50dB. Here, the unit of signal strength may be dB, and has a negative value.

Next, in the exponentiation step (S120), the signal strength is indexed using the signal strength and a threshold value of the received radio signal.

In general, the signal strength has a value between 0 and -100, and when a user or a mobile device scans an AP, even weak signals are detected. In this case, since the closer the AP and the user's location are, the stronger the signal strength is. Therefore, if only a strong signal is selected based on the threshold, only the APs located on a few floors adjacent to the floor where the user is located are primarily left. .

Signal strength is characterized by stronger (closer to 0) as the AP and user are closer, but the signal strength may be momentarily weak due to the influence of obstacles or environmental factors. In addition, the same value may be observed in APs located on different floors. Therefore, the location cannot be specified based on the AP with the strongest signal strength, and the floor must be determined using multiple AP candidates.

In this way, in order to determine a layer using several AP candidates, a plurality of dominant signals are selected using a threshold value in this example. Such processing is referred to as signal selection in the following Fig. 4 and the following description.

For example, if the threshold is set to -60 as shown in FIG. 4, in the signal selection, signals having signal strengths of -50 dB, -40 dB, -56 dB, and -59 dB stronger than -60 dB are dominant signals. can be selected as

In the example of FIG. 4 , the dominant signals include only signals from APs installed on the first and second floors among the APs installed on all floors, and the remaining layers are excluded from the candidate layer by the threshold value.

Also, in this example, the step of selecting a dominant signal having the signal strength greater than or equal to the threshold value and adjusting the threshold value when the dominant signal is not selected may be performed. It is unknown what kind of distribution the signal strength has in an unspecified place. Therefore, a method of assigning an initial threshold to a rather low value and selecting an AP to be analyzed is applied. That is, in the step of adjusting the threshold, the dominant signal is selected while lowering the threshold from the initial threshold to a preset level. For this example, if the initial threshold is set to -60 but the AP is not selected, the threshold is lowered by a preset strength, for example, -5, and updated so that the AP can be selected.

On the other hand, when determining the location by calculating and averaging the floor information for the selected dominant signal, the accuracy deteriorates. Therefore, in the present invention, the signal intensity is indexed based on the threshold value and used. In this case, in the step of performing the exponentiation, the exponentiation may be performed using the difference between the signal strength and the threshold value so that the signal having the high signal strength has a large number based on the threshold value.

That is, RSSI exponentiation (R) may be defined as RSSI-threshold value. As a specific example, referring to FIG. 4 , an AP having a MAC address of AA:BB:CC:aa:bb:00 is an AP located on the first floor, and the indexing (R) is -50-(-60), which is 10. can be

In addition, in the weight calculation performing step ( S130 ) shown in FIG. 3 , an operation is performed to derive a more accurate result by changing the indexing using the weight, and the floor information on which the user is located in the current location detection step ( S140 ) is performed. will acquire

와

가 이용되며, 따라서 상기 연산부는 최종 결과를 정수로 반환할 수 있다.According to an example of the present invention, the calculation unit directly applies the weight to the integerized layer information to return the final result as an integer. For example, the floor information (floor_num) is an integer type ID that distinguishes the floors of a building, and the indexing (R) is an integer value because it is the difference between the signal strength and the threshold value. In this case, as the weight

Wow

is used, and thus the operation unit may return the final result as an integer.

The result returned as an integer provides intuitive information, so it is easy to use. In this process, if the signal strength is used as it is for the weight calculation, the weaker the signal, the higher the score. do.

In addition, in the present invention, accuracy is improved by weighting a signal having a strong signal strength. For the weight calculation method, the following formula may be applied. However, if the signal strength is used as it is in this process, a high weight may be given to a weak signal, so as described above, it is set to give a high weight to a strong signal through exponentiation as described above.

, 여기서, round = 반올림 연산

, where round = rounding operation

Here, the rounding operation result may be defined as F, where F may mean a predicted value of a floor in which the user is located.

For example, referring to FIG. 4 , the numerator of the formula may be 80, the denominator may be 55, and 1 is calculated as the result (F) of the rounding operation. Accordingly, the current location of the user or mobile device may be the first floor. If only an arithmetic mean is used or only a weight is applied without exponentiation, 2 can be derived. However, using the equation according to an example of the present invention, the user's current location is accurately calculated as the first floor. Through this, it can be seen that the indoor positioning method of the present invention is more accurate. In addition, in the present invention, even if the buildings are different, only the signal strength itself is indexed based on the threshold value and this is used, so it is possible to classify floors including all buildings in the search range.

The indoor positioning method and system according to the present invention described above implements a simpler and more accurate indoor positioning by using a process that indexes only the signal strength itself based on a threshold value and utilizes it.

In addition, the indoor positioning method and system described above may be modified in various forms. As an example, the indoor positioning method and system described above may be implemented as an indoor positioning method capable of accurate positioning even when a wireless signal received from an AP of another building is mixed.

Hereinafter, a process in which a function for classifying a building is added as a modified example or another embodiment of the present invention will be described with reference to FIGS. 5 and 6 . In addition, in the modification or embodiment described below, the same or similar reference numerals are assigned to the same or similar components as in the previous example, and the description is replaced with the first description.

5 is a flowchart representatively illustrating an indoor positioning method according to another embodiment of the present invention, and FIG. 6 is an exemplary diagram for explaining the indoor positioning method of FIG. 5 in detail.

Referring to the drawings, the indoor positioning method divides a building through a primary operation and divides a floor through a secondary operation. As such an example, the indoor positioning method may consist of a process of receiving a signal (S210), detecting a building (S220), detecting a floor (S230), and detecting a current location (S240).

First, in the signal receiving step ( S210 ), the mobile device receives wireless signals from a plurality of APs installed at least one or more on each floor of a building. In this case, the mobile device receives a wireless signal from an AP installed in another building.

In the signal receiving step (S210), the wireless communication unit of the mobile device, for example, using a Wi-Fi signal, similarly to the signal receiving step (S110, see FIG. 3) of the embodiment described with reference to FIGS. 3 and 4 . Receives unique ID (MAC) and signal strength (RSSI) of wireless communication equipment from multiple APs.

However, in this case, the DB management unit manages the paired information of [AP MAC address, building information, floor information] as a DB, and the calculation unit manages the paired information of [AP MAC address, building information, floor information]. is used to collect the building information and floor information of the corresponding AP.

In the embodiment described with reference to FIGS. 3 and 4, without separate building information, floor information of a different numerical range is allocated to each building, so that both the building information and the floor information can be detected only with the value of the floor information. The case has been described as an example. For example, it has been explained that it is possible to allocate and use a range of floor information values for each building so that the floor information values of the APs of different buildings have a difference of at least 10 or more. In the present embodiment described with reference to FIGS. 5 and 6 , a case in which information in which [AP MAC address, building information, and floor information] is paired is used will be described. As described above, in this example, a building is separately detected by separating the integer representing the floor information and the building information, and a filter is applied to the building when the floor is detected.

More specifically, the building detection step ( S220 ) detects building information of the AP that has transmitted the wireless signal using the wireless signal received by the mobile device.

The building detection step (S220) is a step in which the calculator performs a primary operation, and the mobile device detects building information from signals collected from APs installed in different buildings, and determines the location of the mobile device floor. It can be a step in determining the target building to be carried out.

In this case, the building detection step ( S220 ) may include an indexing step and a weight calculation performing step. Specifically, the building detection step (S220) performs the indexing of the signal strength using the signal strength of the signal including the building information and the threshold value for building positioning, and assigns the building information to the indexed signal strength. It is reflected and weighted, and the target building is determined using the weighted result value.

For example, referring to FIG. 6 , the DB management unit collects building information of the corresponding AP by using paired information [MAC address of AP, building information]. For example, when information of [AA:BB:CC:aa:bb:00, 1] is stored in the DB management unit, the AP with the MAC address of AA:BB:CC:aa:bb:00 is located in Building A. It can be an AP.

Since the wireless signal collected by the mobile device has information of [AP MAC address, RSSI], for example, when the wireless signal is [AA:BB:CC:aa:bb:00, -50], The AP with AA:BB:CC:aa:bb:00 as the MAC address is located in Building A, and the corresponding wireless signal is the reception of a signal with a signal strength of -50dB from the AP in Building A. Here, the unit of signal strength may be dB, and has a negative value.

Next, the calculating unit calculates the sum of the exponentiation and weight of FIG. 6 in the same manner as in the exponentiation step and the weight calculation performing step of the embodiment described above with reference to FIGS. 3 and 4 . However, the building is detected by changing floor_num to building_num in [MAC, floor_num] of the DB management unit storing floor information as data together with the MAC address of the AP.

For example, indexing is performed on the signal strength using the signal strength of the received radio signal and a threshold value for positioning a building. 6, when the threshold for building positioning is set to -60, signals having signal strengths of -50dB, -40dB, -56dB, and -59dB stronger than -60dB can be selected as dominant signals.

The dominant signals are APs having signal strength greater than the threshold for building positioning, and in this example include only signals received from APs installed in buildings A and B. Accordingly, the remaining buildings are excluded from the candidate buildings by the threshold value for building positioning. Unlike the signal selection of the embodiment described above with reference to FIGS. 3 and 4 , this processing is a signal processing that is preferentially performed for building positioning, and is referred to as “primary selection” in the following description and drawings.

In addition, in the first screening, the signal strength of the signal strength greater than or equal to the threshold value for positioning the building is selected, and when the dominant signal is not selected, the step of adjusting the threshold value for positioning the building may be performed. For this example, if the initial building positioning threshold is set to -60 but the AP is not selected, the threshold value for building positioning is lowered by a preset intensity, for example, -5, and updated so that the AP can be selected.

In the step of performing the indexing, the indexing may be performed using the difference between the signal strength and the threshold value for the building positioning so that the signal having the strong signal strength has a large number based on the threshold value for the building positioning.

Also in this example, RSSI indexing (R) may be defined as "RSSI - threshold for building positioning". As a specific example, referring to FIG. 6 , an AP having a MAC address of AA:BB:CC:aa:bb:00 is an AP located in a building A, and the indexing (R) is -50-(-60), which is 10. can be

As another example, an AP having a MAC address of AA:BB:CC:aa:bb:03 is an AP located in building B, and the exponentiation (R) may be -40-(-60) to 20.

Next, by calculating the weighted sum of the indexing, building information is acquired in the building detection step ( S220 ).

For the weight sum calculation method, the following formula may be applied. However, if the signal strength is used as it is in this process, a high weight may be given to a weak signal, so as described above, it is set to give a high weight to a strong signal through exponentiation as described above.

, 여기서, round = 반올림 연산

, where round = rounding operation

Here, the rounding operation result may be defined as B, and B may mean a predicted value of a building in which the user is located.

For example, referring to FIG. 6 , the numerator of the formula may be 80, the denominator may be 55, and 1 is calculated as a result of the rounding operation. Thus, the current location of the user or mobile device may be building A.

Next, in the floor detecting step (S230) and the current location detecting step (S240), the calculating unit uses only the signal corresponding to the building detected in the building detecting step (S220) among the first selected signals for floor information. perform calculations For example, in the example of FIG. 6 , the operation unit may include a signal [AA:BB:CC:aa:bb:00, -50], [AA:BB:CC:aa:bb:01, -40] or only the exponential value of the corresponding signal is used to perform the calculation, and the signal information corresponding to a building other than the target building is first selected. Even if it is a signal, it may not be used in the calculation of the layer detection step S230. That is, a wireless signal received from an AP in a building different from the target building may be filtered when positioning the mobile device on a floor. More specifically, in the floor detection step ( S230 ), signal information corresponding to a building other than the target building may be filtered by using the signal selection described with reference to FIG. 4 . In this case, the signal selection may be referred to as secondary selection.

In the floor detection step (S230) and the current location detection step (S240), only the signal corresponding to the building A (hereinafter referred to as the 'target building') detected in the building detection step (S220) is selected and used, A specific calculation method using the selected signal may be performed in the same manner as the method of determining the floor on which the user or mobile device is located, as described above with reference to FIGS. 3 and 4 . Accordingly, a description thereof is replaced with a description of the above-described example with reference to FIGS. 3 and 4 .

However, in this case, the threshold value used in the floor detection step may be set to the same value as the threshold value for positioning the building. For this example, if the threshold value for building positioning is set to -60, the threshold value of the floor detection step may also be set to -60. As such, by using the same threshold value, the primary operation for specifying the building and the secondary operation for specifying the floor may be sequentially performed without changing the threshold.

According to the above description, the building on which the mobile device is located may be detected as “Building A” according to the process of FIG. 6 , and the floor on which the mobile device is located may be detected as “the first floor” according to the process of FIG. 4 . . Consequently, the initial location of the mobile device may be the first floor of building A.

In addition, the indoor positioning method and system described above can be applied in various forms. As an example, the indoor positioning method and system described above can also be applied to interfloor movement of a mobile device. Hereinafter, an application example of the present invention will be described with reference to FIG. 7 . In addition, in the application examples described below, the same or similar reference numerals are assigned to the same or similar components as in the previous example, and the description is replaced with the first description.

7 is a conceptual diagram illustrating another embodiment of an indoor positioning method and system according to the present invention.

Referring to this figure, the indoor positioning method may further include detecting a movement between floors of the mobile device, and when the movement between floors is sensed, positioning of the floor of the mobile device may be performed.

In this case, the mobile device may be a service robot, such as a delivery robot or a guide robot. However, the robot R according to the present example may be variously named, for example, may be expressed as an unmanned moving machine, an autonomous moving machine, or the like.

The robot R may be configured to travel in a space as shown in FIG. 7 in order to perform a given task, such as providing a service. There is no limitation on the type of space in which the robot R travels, and it may be configured to travel in at least one of an indoor space and an outdoor space as necessary. In this case, the indoor space may be a space of a multi-story building such as a department store, an airport, a hotel, a school, a building, a subway station, a train station, a bookstore, and the like. The robot R, as described above, may be arranged on any one floor of various buildings to provide useful services to humans.

On the other hand, in order to provide various services using the robot R, it is a very important factor for the robot to accurately and quickly check its position. Accordingly, when the robot moves between floors, it is possible to quickly identify a floor located therein.

The situation in which the movement between floors is sensed is, for example, 1) when an altitude change is detected by another sensor such as an IMU or altimeter, 2) getting off the elevator 3) When the device is not used for a certain period of time and use is started, 4) When the central server detects the movement of the device between floors, etc.

In this figure, the robot (R) moves on the elevator (E) and exemplifies a case in which the robot (R) gets off the elevator (E). When the robot R gets off the elevator E, it is predicted that there has been an inter-floor movement, and the robot R performs the indoor positioning method of the present invention. More specifically, it receives radio signals from a plurality of APs, checks the floor on which it is located, and then requests detailed information on the floor corresponding to the server. According to an example, the robot (R) is, through communication with a building control server, or through an elevator boarding command or getting off command generated inside the robot (R) or transmitted to the inside of the robot (R), or the Through the recognition of the surroundings using the sensor provided in the robot (R), it can be recognized that the robot (R) got off the elevator (E).

However, in this example, the case of sensing the movement between floors is exemplified, but the present invention is not necessarily limited thereto. For example, if information on a corresponding layer is required, the present invention can be applied in any case. Specifically, when the mobile device is powered on while the power is off, it is also possible to update information by performing positioning on a floor.

As described above, the present invention provides an indoor positioning method and system capable of classifying floors including all buildings in a search range by utilizing signal strength even if the buildings are different.

Specifically, in the present invention, by using a method of indexing the signal strength based on a threshold value and changing it to a weight, it is possible to classify floors including all buildings in the search range.

In the indoor positioning method and system described above, the configuration and method of the above-described embodiments are not limitedly applicable, but all or part of each embodiment is selectively combined so that various modifications can be made. may be configured.

Claims (15)

receiving, by a mobile device, a wireless signal from a plurality of APs installed at least one or more on each floor of a building;
performing exponentiation on the signal strength using a difference between the signal strength of the received radio signal and a threshold value; and
By using the received wireless signal, layer information that distinguishes the floor where the AP transmitting the wireless signal is installed is detected, the layer information is reflected in the indexed signal strength and weight is given, and the weighted Comprising the step of performing positioning on the floor of the mobile device using the result value,
The threshold is
As a result of selecting the dominant signal having the signal strength equal to or greater than the threshold value, the indoor positioning method is adjusted when the dominant signal is not selected. According to claim 1,
The step of performing the exponentiation is,
Indoor positioning method, characterized in that the indexing is performed using the difference between the signal strength and the threshold value so that the signal having the high signal strength has a large number based on the threshold value. delete According to claim 1,
The adjusting of the threshold value is an indoor positioning method, characterized in that the dominant signal is selected while lowering the threshold value from an initial threshold value to a preset level. According to claim 1,
The indoor positioning method further comprising the step of determining, by the mobile device, building information from APs installed in different buildings, and determining a target building to be positioned on the floor of the mobile device. 6. The method of claim 5,
The step of determining the target building,
Exponentiation is performed on the signal strength using the signal strength of the signal including the building information and the threshold for building positioning, and the building information is reflected in the indexed signal strength to give weight, and the weight is given Indoor positioning method, characterized in that for determining the target building using the obtained result value. 7. The method of claim 6,
The threshold value is an indoor positioning method, characterized in that set to the same value as the threshold value for positioning the building. 6. The method of claim 5,
The indoor positioning method, characterized in that the wireless signal received from the AP of a building different from the target building is filtered when positioning the floor of the mobile device. According to claim 1,
The indoor positioning method, characterized in that the mobile device requests a DB corresponding to the floor on which the mobile device is located, determined by performing positioning on the floor, to a server. According to claim 1,
Further comprising the step of detecting the movement of the mobile device between floors,
When the movement between floors is sensed, the indoor positioning method according to claim 1 , wherein positioning is performed on the floor of the mobile device. receiving, by the mobile device, wireless signals from a plurality of APs;
detecting building information of an AP that has transmitted the wireless signal using the wireless signal;
performing indexing on the signal strength using the signal strength and threshold value of the wireless signal, and detecting a building using the indexed signal strength and the building information;
detecting layer information of an AP that has transmitted the wireless signal using the wireless signal; and
Based on the detected building, indoor positioning method comprising the step of performing positioning on the floor of the mobile device using the indexed signal strength and the floor information. 12. The method of claim 11,
The indoor positioning method, characterized in that the wireless signal received from the AP of a building different from the detected building is filtered when positioning the floor of the mobile device. 12. The method of claim 11,
Indoor positioning method, characterized in that the indexing is performed using the difference between the signal strength and the threshold value so that the signal having the high signal strength has a large number based on the threshold value. 14. The method of claim 13,
Selecting a dominant signal in which the signal strength is greater than the threshold value,
The indoor positioning method further comprising the step of adjusting the threshold value when the dominant signal is not selected. a database for storing at least one of building information and floor information as data together with the MAC address of the AP; and
Comprising a calculation unit for performing positioning on the floor on which the mobile device receiving the wireless signal from the AP is located,
The calculation unit,
performing exponentiation of the signal strength using a difference between the signal strength of the radio signal and a threshold value; and
Detects the floor information that distinguishes the floor on which the AP transmitting the wireless signal is installed, reflects the floor information to the indexed signal strength, gives weight, and uses the weighted result value of the mobile device. Carrying out the steps of performing the positioning on the floor,
The threshold is
As a result of selecting the dominant signal having the signal strength equal to or greater than the threshold value, the indoor positioning system is adjusted when the dominant signal is not selected.

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