Indoor positioning system and method using reflected light

Abstract

The present invention relates to an indoor positioning system and method. Provided are an indoor positioning system and method using reflected light that are configured to, by using an optical signal transceiver and a reflector array composed of retroreflectors having the same incident angle and reflection angle of an optical signal, calculate a distance to the reflector array on the basis of reception information of the optical signal, and to calculate an absolute position of a user on the basis of the distance information and absolute position information of each reflecting surface of the reflector array, thereby accurately tracking the position of a user indoors with a simpler configuration and at a lower cost.

Description

Indoor positioning system and method using reflected light

[0001] The present invention relates to an indoor positioning system and method for accurately tracking a user's location indoors, and more specifically, to a system and method for indoor positioning using reflected light, which are configured to accurately identify and track a user's location even indoors where satellite signals are difficult to reach, and thus have limitations in implementing user location-based services that require a high-accuracy indoor positioning system, such as autonomous parking in underground parking lots, or wayfinding, location-based advertising, and entertainment in large indoor spaces such as large shopping malls, in order to solve the problems of conventional location tracking devices and methods, which have limitations in that various services, such as map services and location-based services, are provided using satellite navigation systems such as GPS (Global Position System).

[0002] In addition, the present invention relates to an indoor positioning system and method using reflected light, which is configured to accurately track a user's location indoors in a manner that is difficult for satellite signals to reach, for example, based on various radio frequency (RF) communications such as satellites, beacons, Wi-Fi / WLAN / Wireless LAN, RFID, active RFID, mobile communications, Bluetooth, UWB (Ultra-WideBand), Zigbee, WiBro / WiMax, broadcast signals, etc., and which calculates the user's location based on the distance between transmitters and receivers and the reception time of the radio signal, but has the disadvantage of relatively low accuracy, and has the limitation of requiring a large number of transmitters and receivers to increase the accuracy of position measurement, thereby requiring expensive infrastructure construction costs. In order to solve the problems of the prior art, the present invention relates to an indoor positioning system and method using reflected light, which is configured to accurately track a user's location indoors in a simpler configuration and at a lower cost by using reflected light instead of wireless communications.

[0003] In addition, the present invention, in order to accurately track the location of a user indoors with a simpler configuration and at a lower cost using reflected light as described above, the indoor location of the user can be determined through the location information of three or more reflective surfaces that reflect the incident optical signal as reflected light of different frequencies (colors) and the distance information from each reflective surface to the user, but each reflective surface must reflect the reflected light with a different frequency and there is a limitation that a sensor satisfying sufficient sensitivity range and communication speed is required to detect this. In order to solve the problem of the indoor positioning system and method using reflected light of the prior art, the present invention uses a reflector array made of retroreflectors having the same incident angle and reflection angle of the optical signal and an optical signal transceiver to calculate the distance to the reflector array based on the reception information of the optical signal and calculate the absolute location of the user based on the distance information and the absolute location information of each reflective surface of the reflector array, thereby enabling the location of the user indoors to be accurately tracked with a simpler configuration and at a lower cost without the need to apply reflected light of different frequencies to each reflective surface or develop a separate sensor. It relates to an indoor positioning system and method.

[0004]

[0005] Recently, with the widespread use of personal information and communication devices such as smartphones, the user location-based service industry, which provides content, advertisements, or customized information based on the user's current location, is growing rapidly.

[0006] In addition, in order to provide such user location-based services, it is essential to accurately determine the user's location, and if the user is outdoors, a satellite navigation system (Global Position System; GPS) can be utilized, which receives signals from multiple satellites, measures the distance from the satellites, and determines the user's location.

[0007] However, when a user is in an indoor environment, there is a limitation in using the global positioning system (GPS) for positioning because it is difficult for satellite signals to reach indoors. Therefore, for example, in order to implement autonomous parking functions in underground parking lots, or to provide services such as route finding, location-based advertising, and entertainment using smartphones in large indoor spaces such as airports or large shopping malls, an indoor positioning system with high accuracy that does not use GPS is required.

[0008] Accordingly, in order to track the location of a user indoors, indoor positioning systems that are mainly configured using radio frequency (RF) communication devices, such as satellite-based, terrestrial beacon-based, wireless LAN (Wi-Fi / WLAN / Wireless LAN)-based, RFID-based, active RFID-based, mobile communication-based, Bluetooth-based, UWB-based, Zigbee-based, WiBro / WiMax-based, and broadcast signal-based systems, are being used.

[0009] More specifically, one of the most widely used indoor positioning methods today is to estimate the distance between a transmitter and a receiver using the received signal and calculate the user's location. Various radio frequency signals such as Wifi / Bluetooth, UWB, and mobile communication are used as the signal.

[0010] Here, indoor positioning technology based on Wifi / Bluetooth has the advantage of being able to build infrastructure at a relatively low cost, but has the disadvantage of showing a relatively low level of accuracy (1 to 10 m). On the other hand, UWB indoor positioning technology provides relatively high accuracy (10 cm to 1 m), but has the disadvantage of requiring expensive infrastructure construction costs because multiple transmitters must be installed for position measurement.

[0011] Moreover, existing indoor positioning technologies based on radio signals have problems such as difficulty in building infrastructure, continuous power consumption, signal interference problems due to radio wave characteristics (BLE), and limitations in the number of multiple users (UWB) due to distance measurement using radio signals such as Wi-Fi, Bluetooth (BLE), and UWB.

[0012] In order to solve these problems, according to the "Indoor positioning system and method using reflected light" of Korean Patent Publication No. 10-2180304, a technical content has been proposed to enable the user's position to be determined in an indoor environment by using a terminal that transmits and receives an optical signal and a plurality of reflective surfaces that reflect the optical signal as reflected light of different frequencies (wavelengths), thereby enabling the user's position to be measured indoors with a simpler configuration and lower cost compared to existing wireless communication-based indoor positioning systems and methods. However, the content of the above-mentioned conventional technology had the following limitations.

[0013] More specifically, the "indoor positioning system and method using reflected light" of the above-mentioned Korean Patent Publication No. 10-2180304 comprises a reflector comprising at least one reflective surface and a user terminal for determining a user's location based on distance information, wherein each reflective surface is configured to reflect an incident optical signal as reflected light of different frequencies (colors), and the indoor position of the user is determined based on location information of three or more reflective surfaces and distance information from the reflective surfaces to the user.

[0014] However, the "Indoor positioning system and method using reflected light" of the above-mentioned Korean Patent Publication No. 10-2180304 had limitations in that each reflective surface must reflect reflected light at a different frequency, and in order to put it into practical use, a sensor that satisfies sufficient sensitivity distance and communication speed is additionally required.

[0015] Therefore, in order to solve the limitations of the indoor positioning systems and methods of the prior art as described above, it is desirable to propose a new indoor positioning system and method that can accurately track the location of a user even indoors, while being configured to be implemented with a simpler configuration and lower cost than before. However, a device or method that satisfies all of these requirements has not yet been proposed.

[0016]

[0017] [Prior Art Literature]

[0018] Korean Patent Publication No. 10-2180304 (November 18, 2020)

[0019]

[0020] The present invention is intended to solve the problems of the prior art as described above, and therefore, the purpose of the present invention is that, although various services such as map services and location-based services are provided using satellite navigation systems such as GPS (Global Position System), it is difficult to accurately track a user's location indoors due to the difficulty of satellite signals reaching therein, and therefore, implementation of user location-based services requiring a high-accuracy indoor positioning system, such as autonomous parking functions in underground parking lots, or wayfinding, location-based advertising, and entertainment in large indoor spaces such as large shopping malls, is limited. In order to solve the problems of the prior art location tracking devices and methods, the present invention proposes an indoor positioning system and method using reflected light, which are configured to accurately identify and track a user's location even indoors where satellite signals are difficult to reach.

[0021] In addition, another object of the present invention is to provide an indoor positioning system and method using reflected light, which is configured to accurately identify and track the location of a user indoors where satellite signals have difficulty reaching, for example, satellites, beacons, wireless LAN (Wi-Fi / WLAN / Wireless LAN), RFID, active RFID, mobile communications, Bluetooth, UWB (Ultra-WideBand), Zigbee, WiBro / WiMax, broadcast signals, etc., and which can calculate the location of a user based on the distance between transmitters and receivers and the reception time of a radio signal, but which has the disadvantage of relatively low accuracy, and which has the limitation of requiring a large number of transmitters and receivers to increase the accuracy of position measurement, thereby requiring expensive infrastructure construction costs. In order to solve the problems of the conventional wireless communication-based indoor positioning system and method, the present invention proposes an indoor positioning system and method using reflected light, which is configured to accurately track the location of a user indoors with a simpler configuration and lower cost by using reflected light instead of wireless communication.

[0022] In addition, another object of the present invention is to accurately track the location of a user indoors with a simpler configuration and at a lower cost by using reflected light as described above, and to determine the indoor location of a user through the location information of three or more reflective surfaces that reflect an incident optical signal with reflected light of different frequencies (colors) and the distance information from each reflective surface to the user, but each reflective surface must reflect reflected light with a different frequency and there is a limitation that a sensor satisfying sufficient sensitivity range and communication speed is required to detect this. In order to solve the problem of the conventional indoor positioning system and method using reflected light, the present invention provides a system that calculates the distance to the reflector array based on the reception information of the optical signal and calculates the absolute location of the user based on the distance information and the absolute location information of each reflective surface of the reflector array using a reflector array made of retroreflectors having the same incident angle and reflection angle of the optical signal and an optical signal transceiver, thereby enabling the accurate tracking of the location of a user indoors with a simpler configuration and at a lower cost without the need to apply reflected light of different frequencies to each reflective surface or develop a separate sensor. The purpose of this paper is to propose an indoor positioning system and method using the same.

[0023]

[0024] In order to achieve the above-mentioned object, according to the present invention, an indoor positioning system using reflected light is provided, characterized in that it comprises a reflector array including a reflector array in which a plurality of retroreflectors having the same incident angle and reflection angle of an optical signal are arranged in a predetermined number and interval; and a user terminal configured to perform processing for determining a user's location using reflected light received through each of the reflectors of the reflector array.

[0025] Here, the reflector array is characterized in that each of the retroreflectors is installed at a predetermined location to form the reflector array.

[0026] Alternatively, the reflector array is characterized in that each of the retroreflectors is arranged in a predetermined arrangement so that the reflector array formed integrally is installed at a predetermined position.

[0027] Alternatively, the reflector array section is characterized in that it is configured to include a plurality of retroreflectors each formed in a different shape using a reflective tape (film) including a corner cube retroreflector (CCR) of a single prism type, a prism reflective tape of a prism array type, or a glass bead reflective tape of a micro glass bead type, so that the reflector array can be detected through the shape of each retroreflector and each retroreflector can be identified.

[0028] In addition, the indoor positioning system is characterized in that it further includes a server in which location information for each reflector of the reflector array is stored in advance and processing is performed to transmit the corresponding information to the user terminal upon request of the user terminal.

[0029] Alternatively, the indoor positioning system is characterized in that location information for each reflector of the reflector array is stored in advance in the user terminal.

[0030] In addition, the user terminal is characterized in that it comprises an optical signal transmitting unit configured to perform processing for transmitting an optical signal according to predetermined settings; an optical signal receiving unit configured to perform processing for receiving an optical signal reflected through the reflector array unit; a reflector detecting unit configured to perform processing for identifying each reflector of the reflector array unit based on the received optical signal; a distance calculating unit configured to perform processing for calculating a distance between the user terminal and the reflector array unit based on reception information of the optical signal; a position determining unit configured to perform processing for calculating a position of the user terminal using the calculated distance information and position information of each reflector; and a data storage unit configured to perform processing for storing various data obtained through processing and processing results of the optical signal transmitting unit, the optical signal receiving unit, the reflector detecting unit, the distance calculating unit, and the position determining unit according to predetermined settings.

[0031] Here, the user terminal is characterized in that it comprises a detection sensor capable of receiving at least one of intensity, brightness, and saturation of reflected light and a distance sensor capable of calculating a distance from a transmitted and received optical signal.

[0032] Alternatively, the user terminal is characterized in that it is configured by installing a dedicated application on a personal information and communication device including a smartphone having a TOF camera function.

[0033] Furthermore, the reflector detection unit is characterized in that it is configured to detect a reflector array using at least one piece of information among intensity, brightness, saturation, and shape of reflected light according to a predetermined setting based on an optical signal received through the optical signal receiving unit, and to perform a process of identifying each reflector by comparing the relative distance between each reflector of the detected reflector array and the actual distance between each reflector based on the positional information of the reflector array stored in advance.

[0034] In addition, the distance calculation unit is characterized in that it is configured to perform processing to calculate the distance from the user terminal to the reflector array unit using a TOF (Time of Flight) method that calculates the distance using the difference in transmission and reception times based on the reception information of the optical signal received through the optical signal receiving unit.

[0035] Alternatively, the distance calculation unit is characterized in that it is configured to perform processing to calculate the distance from the user terminal to the reflector array unit using the carrier phase measurement value of the received reflected light signal based on the reception information of the optical signal received through the optical signal receiving unit.

[0036] In addition, the position determination unit is characterized in that it is configured to perform processing to calculate the absolute position of the user terminal using a triangulation technique based on the distance information calculated through the distance calculation unit and the position information of the reflector array stored in advance.

[0037] Furthermore, the indoor positioning system is characterized in that it is configured to store various data including the user's location, movement distance, and movement time by time obtained through each processing process and result of the optical signal transmitter, the optical signal receiver, the reflector detector, the distance calculator, and the position determination unit in the data storage means according to predetermined settings and transmit the data to a server or an external device to build a database related to the user's location and movement for each user, and to perform processing to provide corresponding information in a customized manner according to a user's request received through the user terminal based on the contents of the database.

[0038] In addition, the indoor positioning system is characterized in that the reflector array unit is configured to include a plurality of reflector arrays having different arrangement forms, or is configured to provide predetermined identification information to each reflector array so that identification of the plurality of reflector arrays is possible, and different reflector arrays are installed in each indoor space, and location information for each reflector array is stored in advance in a server or a separate database, and a process is performed to identify the reflector array installed in the corresponding indoor space through the user terminal to determine the location, so that the user's location can be accurately determined even in an indoor space that includes a plurality of floors or rooms.

[0039] In addition, according to the present invention, in a method for indoor positioning using reflected light, which is configured to determine a user's location indoors using the indoor positioning system using reflected light described above, the method comprises: an optical signal transmitting step in which processing is performed to transmit an optical signal through an optical signal transmitting unit of a user terminal of the indoor positioning system using reflected light; an optical signal receiving step in which processing is performed to receive an optical signal transmitted through the optical signal transmitting step and reflected from a reflector array unit of the indoor positioning system through the optical signal transmitting unit of the user terminal; a reflector detection step in which processing is performed to detect an array of reflectors and identify each reflector based on the optical signal received in the optical signal receiving step through a reflector detection unit of the user terminal; a distance calculating step in which processing is performed to calculate a distance from the user terminal to each reflector based on an identification result of the reflector detection step and reception information of the optical signal through a distance calculating unit of the user terminal; An indoor positioning method using reflected light is provided, characterized in that it comprises a position determination step in which a process of determining the position of the user terminal using a triangulation technique based on the distance calculated through the distance calculation step and the position information of each reflective surface is performed through a position determination unit of the user terminal.

[0040] Here, the method is characterized in that it further comprises a database construction step in which various data including the user's hourly location, movement distance, and movement time obtained through the processing and results of the optical signal transmitting step, the optical signal receiving step, the reflector detecting step, the distance calculating step, and the position determining step are transmitted to a server or an external device according to predetermined settings to construct a database related to the user's location and movement for each user; and an information providing step in which processing is performed to provide corresponding information in a customized manner according to a user's request received through the user terminal based on the contents of the database constructed through the database construction step.

[0041] Furthermore, according to the present invention, a location information service providing system configured to provide location information to a user both indoors and outdoors according to the user's location is provided, characterized in that it comprises an outdoor positioning unit configured to perform processing to provide location information of the user outdoors using a location tracking device including a GPS; and an indoor positioning unit configured to perform processing to provide location information of the user indoors using the indoor positioning system using reflected light described above.

[0042] In addition, according to the present invention, a location information service providing method configured to provide location information to a user both indoors and outdoors according to the user's location is provided, characterized in that it comprises an outdoor positioning step in which processing is performed to provide location information of the user outdoors using a location tracking device including a GPS; and an indoor positioning step in which processing is performed to provide location information of the user indoors using the indoor positioning system using reflected light described above.

[0043]

[0044] As described above, according to the present invention, an indoor positioning system and method using reflected light are provided, which are configured to accurately track the location of a user indoors with a simpler configuration and lower cost, by calculating the distance to the reflector array based on the reception information of the optical signal using a reflector array composed of retroreflectors having the same incident angle and reflection angle of an optical signal and an optical signal transceiver, and calculating the absolute location of the user based on the distance information and the absolute location information of each reflective surface of the reflector array, without the need to apply reflected light of different frequencies to each reflective surface or develop a separate sensor, thereby solving the problems of the indoor positioning system and method using reflected light of the prior art, which can determine the indoor location of the user through the location information of three or more reflective surfaces configured to reflect the incident optical signal as reflected light of different frequencies (colors) and the distance information from each reflective surface to the user, but have the limitation that each reflective surface must reflect reflected light of different frequencies and a sensor satisfying sufficient sensitivity range and communication speed is required to detect this.

[0045] In addition, according to the present invention, an indoor positioning system and method using reflected light are provided, which are configured to accurately track the location of a user indoors with a simpler configuration and at a lower cost by using reflected light as described above, so that, for example, the location of a user can be calculated based on the distance between transmitters and receivers and the reception time of a wireless signal based on various radio frequency (RF) communications such as satellites, beacons, wireless LAN (Wi-Fi / WLAN / Wireless LAN), RFID, active RFID, mobile communications, Bluetooth, UWB (Ultra-WideBand), Zigbee, WiBro / WiMax, broadcast signals, etc., but have the disadvantage of relatively low accuracy, and have the limitation of requiring a large number of transmitters and receivers to increase the accuracy of position measurement, resulting in expensive infrastructure construction costs. By solving the problems of conventional wireless communication-based indoor positioning systems and methods, the location of a user can be accurately tracked indoors with a simpler configuration and at a lower cost by using reflected light instead of wireless communications.

[0046] In addition, according to the present invention, an indoor positioning system and method using reflected light are provided, which are configured to accurately track a user's location indoors with a simpler configuration and at a lower cost by using reflected light as described above, thereby solving the problems of the GPS-based positioning systems and methods of the prior art, which had limitations in that it was difficult to accurately track a user's location indoors due to the difficulty in reaching satellite signals, and thus the implementation of various services based on the user's location was limited, and thus the user's location can be accurately identified and tracked even indoors where satellite signals are difficult to reach, and thereby, user location-based services requiring a high-accuracy indoor positioning system, such as autonomous parking functions in underground parking lots, or wayfinding, location-based advertising, and entertainment in wide indoor spaces such as large shopping malls, can be more easily implemented and provided.

[0047] Moreover, according to the present invention, an indoor positioning system and method using reflected light are provided, which are configured to accurately track the location of a user indoors with a simpler configuration and lower cost by using reflected light as described above, so that, for example, even in a situation where securing visibility is difficult in an emergency situation such as a fire by installing a reflector array in an indoor space, various information such as the location of the user or an escape route can be quickly and accurately identified and provided, and thus have the advantage of being widely applicable in various fields such as firefighting and disaster relief.

[0048]

[0049] Figure 1 is a conceptual diagram schematically showing the overall configuration of an indoor positioning system using reflected light of the prior art.

[0050] Fig. 2 is a block diagram schematically showing the specific configuration of an indoor positioning system using reflected light of the prior art shown in Fig. 1.

[0051] Figure 3 is a conceptual diagram schematically showing the overall configuration of an indoor positioning system using reflected light according to an embodiment of the present invention.

[0052] FIG. 4 is a conceptual diagram schematically showing the configuration of a retroreflector applied to an indoor positioning system using reflected light according to an embodiment of the present invention.

[0053] FIG. 5 is a drawing schematically showing an example of the configuration of a reflector array of an indoor positioning system using reflected light according to an embodiment of the present invention.

[0054] FIG. 6 is a conceptual diagram schematically showing another configuration example of an indoor positioning system using reflected light according to the embodiment of the present invention shown in FIG. 3.

[0055] FIG. 7 is a diagram showing another configuration example of a retroreflector applied to a reflector array of an indoor positioning system using reflected light according to an embodiment of the present invention, and a configuration example of a reflector array in which each retroreflector is implemented in a different shape, and a result of detecting the corresponding reflector array using an IR camera.

[0056] Figure 8 is a block diagram schematically showing the overall configuration of an indoor positioning system using reflected light according to an embodiment of the present invention.

[0057] FIGS. 9 to 11 are conceptual diagrams schematically illustrating a process of detecting a reflector array and identifying each reflector in a reflector detection unit of an indoor positioning system using reflected light according to an embodiment of the present invention.

[0058] Fig. 12 is a flowchart schematically showing the overall configuration of an indoor positioning method using reflected light according to an embodiment of the present invention.

[0059] FIG. 13 is a diagram schematically showing an experimental environment for a verification experiment to verify the actual performance of an indoor positioning system and method using reflected light according to an embodiment of the present invention.

[0060] FIG. 14 and FIG. 15 are drawings each showing the experimental results of a verification experiment to verify the actual performance of an indoor positioning system and method using reflected light according to an embodiment of the present invention.

[0061]

[0062] Hereinafter, with reference to the attached drawings, a specific embodiment of an indoor positioning system and method using reflected light according to the present invention will be described.

[0063] Here, it should be noted that the contents described below are only one embodiment for carrying out the present invention, and the present invention is not limited to the contents of the embodiments described below.

[0064] In addition, in the description of the embodiments of the present invention below, it should be noted that for the sake of brevity, detailed descriptions of parts that are identical or similar to the contents of prior art or that can be easily understood and implemented by those skilled in the art have been omitted.

[0065] Continuing, with reference to the drawings, the specific contents of the indoor positioning system and method using reflected light according to the present invention will be described.

[0066] In more detail, first, referring to FIG. 1, FIG. 1 is a conceptual diagram schematically showing the overall configuration of an indoor positioning system (10) using reflected light of the prior art.

[0067] As shown in Fig. 1, the existing indoor positioning system (10) using reflected light is largely composed of a reflecting unit (R) including a plurality of reflecting surfaces (Ra, Rb, Rc), a server (S) that stores location information of each reflecting surface, and a user terminal (T) that performs processing to determine the user's location.

[0068] Here, the above-mentioned reflective surface can be installed at a certain distance inside a building such as an airport, a shopping mall, a general hospital, etc., and at this time, there is no limitation on the installation location, but it is preferable to install it on the ceiling of the building so that the optical signal is not blocked by obstacles such as pedestrians or furniture.

[0069] Additionally, as shown in Fig. 1, it may be advantageous in terms of positional accuracy for each reflective surface to be distributed at each corner of the indoor space, but they may also be installed in one place in consideration of visibility.

[0070] More specifically, each reflective surface (Ra, Rb, Rc) can be configured to reflect an optical signal (Li) incident from a user terminal (T) into reflected light (Lra, Lrb, Lrc) of different frequencies (wavelengths), i.e., different colors (e.g., green, blue, red). To this end, each reflective surface can be configured to include a filter formed to reflect only a specific frequency, or can be configured as a mirror coated with a color corresponding to a specific frequency.

[0071] Therefore, as shown in Fig. 1, the light signal (Li) output from the user terminal (T) is reflected as green wavelength reflected light (Lra), blue wavelength reflected light (Lrb), and red wavelength reflected light (Lrc) by the green-coated reflective surface (Ra), the blue-coated reflective surface (Rb), and the red-coated reflective surface (Rc), respectively.

[0072] That is, the above-mentioned reflector (R) can be configured to reflect the incident light (Li) back in the direction in which it was incident by forming a corner reflector structure that makes the incident angle and the reflection angle of the optical signal the same, and through this configuration, each reflected light (Lra, Lrb, Lrc) returns back in the direction in which it was incident and reaches the user terminal (T).

[0073] Here, in the embodiment shown in the above-mentioned Figure 1, the difference in frequency of reflected light corresponding to visible light is explained as a difference in color of light, but it is not necessarily limited to this configuration. That is, for example, each reflective surface may be configured to reflect infrared light having different frequencies by using an optical signal such as infrared light rather than visible light.

[0074] In addition, the server (S) can be configured to store location information of each reflective surface (Ra, Rb, Rc) and transmit the stored location information of the reflective surface to the user terminal (T) via a wireless network at the user's request.

[0075] Here, the server (S) may be configured to not only simply store the location information of the reflector, but also directly determine the user's location using the input information or transmit the determined location to an external device or surveillance center.

[0076] Alternatively, the location information of the reflective surface may be pre-stored in the user terminal (T) rather than the server (S), for example, or may be configured to read a QR code attached indoors (including location information of each terminal) using the user terminal (T) or to manually input the location information of the reflective surface.

[0077] In addition, the user terminal (T) may be configured as dedicated hardware that transmits and receives optical signals to calculate the distance to each reflective surface and performs processing to determine the user's location using the user-reflective surface distance information and the reflective surface location information, or may be configured in a form in which an optical transmission / reception module is combined with a commercialized electronic device such as a smartphone.

[0078] Referring to FIG. 2 in more detail, FIG. 2 is a block diagram schematically showing the specific configuration of an indoor positioning system (10) using reflected light of the prior art shown in FIG. 1.

[0079] As shown in Fig. 2, the indoor positioning system (10) using reflected light of the prior art is configured to include a reflector (R), a server (S), and a user terminal (T). At this time, the user terminal (T) may be configured to include a light transmitting unit (301), a light receiving unit (302), a distance calculating unit (303), a storage unit (304), and a position determining unit (305).

[0080] Here, the above-mentioned optical transmission unit (301) may be configured with, for example, an LED or a camera flash for outputting white light, and in the case of using infrared rays, may be configured to include an infrared output device.

[0081] Additionally, the optical signal can determine the respective locations of multiple users in the same indoor space by including an identification code that can identify the users, and can be configured to obtain a desired gain value even from a long distance by using a random code or modulation in the CDMA method, such as a GPS signal.

[0082] In addition, in order to determine the user's location using the triangulation method, it is preferable that the number of reflecting surfaces be three or more, but it is not necessarily limited to this. That is, for example, if there are one or two reflecting surfaces, it is possible to obtain information that the user is located within a certain distance from the reflecting surfaces, or if the user's height (position on the z-axis) is known, the user's location can be determined simply by determining the two-dimensional position, so the user's exact location can be determined even if there are two reflecting surfaces.

[0083] Moreover, if the indoor space is a one-dimensional environment such as a long hallway, the user's approximate location can be determined with just one reflective surface, and if combined with a method of estimating location using the signal strength of an existing AP or mobile network, the location can be determined even with one or two reflective surfaces.

[0084] In addition, the light receiving unit (302) receives reflected light of different frequencies reflected from each reflective surface and detects and distinguishes optical signals of different frequencies. To this end, the light receiving unit may be implemented with an image sensor, a photodiode, a color sensor, or the like.

[0085] That is, taking the case of the configuration shown in Fig. 1 as an example, the above-described light receiving unit (302) can be configured to detect green light (Lra), blue light (Lrb), and red light (Lrc), respectively, and transmit information about the time at which the light signal arrived to the distance calculating unit (303).

[0086] In addition, the distance calculation unit (303) calculates the distance from the user terminal (T) to each reflective surface based on information obtained from the reflected light signal received by the light receiving unit (302). To this end, the distance calculation unit (303) may be configured to calculate the distance from the user terminal (T) to each reflective surface (Ra, Rb, Rc) based on the time difference between the time when the light transmitting unit (301) transmits the light signal and the time when the light receiving unit (302) receives the reflected light.

[0087] Alternatively, the above-described distance calculation unit (303) may be configured to calculate the distance from the user terminal to the reflecting surface using the carrier phase measurement of the reflected light signal received by the reflecting unit (R), and in addition, as long as it is possible to calculate the distance between the transmitting unit and the reflecting surface by receiving the reflected light, various methods may be utilized without being limited to a specific method or means.

[0088] Here, as for more specific details of the processing process of calculating the distance between the transmitter and the reflecting surface by receiving the reflected light as described above, since it is obvious to those skilled in the art by referring to the contents of conventional distance measurement systems and methods such as the triangulation method or the TDOA (Time Difference of Arrival) method or conventional position tracking systems and methods, for example, in the present invention, in order to simplify the explanation, it should be noted that a detailed description of the contents that are obvious to those skilled in the art from the contents of the conventional art as described above or that can be easily understood and implemented by those skilled in the art by referring to documents of the conventional art, etc., has been omitted.

[0089] Therefore, by using the reflected light from the configuration described above to obtain distance information between the user and the reflecting surface through the time difference between transmission and reception of the optical signal, and calculating the user's location by triangulation using the location information of each reflecting surface pre-stored in the server, the user's location can be determined even indoors where GPS is not available. However, the indoor positioning system (10) using the reflected light of the conventional technology described above requires three or more reflecting surfaces configured to reflect the incident optical signal as reflected light of different frequencies (colors), and for this purpose, it has the disadvantage of having a relatively complex configuration of the reflector and increased cost due to the configuration including a filter that reflects only a specific frequency or a mirror coated with a color corresponding to a specific frequency.

[0090] In addition, the indoor positioning system (10) using the reflected light of the above-mentioned prior art additionally requires a relatively high-performance sensor that satisfies sufficient sensitivity range and communication speed to calculate the location by distinguishing the different reflected light received from each reflective surface, and therefore, there was a limitation that it was not easy to put into practice at low cost.

[0091] Accordingly, in order to solve the problems of the indoor positioning system (10) using reflected light of the prior art as described above, the inventors of the present invention have proposed a new indoor positioning system and method using reflected light, which is configured to accurately track the location of a user indoors with a simpler configuration and lower cost than before, as described below.

[0092] Here, in the embodiments of the present invention described below, it should be noted that detailed descriptions have been omitted in order to exclude overlapping content and simplify the explanation, with respect to the same or similar content as the indoor positioning system (10) using reflected light of the prior art shown in FIGS. 1 and 2 and the content that is obvious to those skilled in the art by referring to the content of the prior art as described above or that can be easily understood and implemented by those skilled in the art by referring to the literature of the prior art.

[0093] More specifically, first, referring to FIG. 3, FIG. 3 is a conceptual diagram schematically showing the overall configuration of an indoor positioning system (50) using reflected light according to an embodiment of the present invention.

[0094] As shown in FIG. 3, an indoor positioning system (50) using reflected light according to an embodiment of the present invention can be largely divided into a reflector array (51) including a plurality of reflectors (R1, R2, R3), a user terminal (52) configured to perform processing for determining a user's location using reflected light received through each reflector, and a server (53) in which location information of each reflector is stored.

[0095] Here, the above-mentioned reflector array (51) can be configured to include a reflector array in which two or more retroreflectors are arranged at a predetermined interval and shape, using a retroreflector having the characteristic that the incident angle and the reflection angle of the light signal are the same.

[0096] That is, referring to FIG. 4, FIG. 4 is a conceptual diagram schematically showing the configuration of a retroreflector applied to a reflector array (51) of an indoor positioning system (50) using reflected light according to an embodiment of the present invention.

[0097] As shown in Fig. 4, the above-described reflector array (51) is configured by arranging two or more retroreflectors (R) having the same incident angle and reflection angle of the optical signal in a predetermined specific arrangement, and preferably, it can be configured as a reflector array in which three retroreflectors are arranged.

[0098] That is, referring to FIG. 5, FIG. 5 is a drawing schematically showing an example of the configuration of a reflector array (51) of an indoor positioning system (50) using reflected light according to an embodiment of the present invention.

[0099] As shown in Fig. 5, the above-described reflector array (51) may be configured as a triangular reflector array in which, for example, three retroreflectors (54) are arranged at predetermined intervals.

[0100] In addition, since the retroreflector has the characteristic of reflecting light in the direction in which it is incident and has the characteristic of having relatively little signal loss of the retroreflected optical signal through the reflection characteristics (reflectivity) of the mirror, by configuring the reflector array (51) using the retroreflector as described above, the optical signal transmitted from the user terminal (52) can be received back to the user terminal (52) with sufficient intensity, thereby enabling robust optical signal reception regardless of the user's location.

[0101] Here, in the embodiment shown in FIG. 5, the present invention is illustrated by taking as an example a case where three retroreflectors (51) are arranged in a triangular shape in the reflector array (51), but the present invention is not necessarily limited to this configuration. That is, it should be noted that the above-mentioned retroreflector (54) has no particular restrictions on the shape or structure of the reflector as long as it has the characteristic of reflecting incident light in the same direction, and there is no particular restriction on the arrangement configuration of the reflector array (51).

[0102] That is, referring to FIG. 6, FIG. 6 is a conceptual diagram schematically showing another configuration example of an indoor positioning system (50) using reflected light according to the embodiment of the present invention shown in FIG. 4.

[0103] As shown in FIGS. 3 and 6, the reflector array (51) may be configured, for example, with three retroreflectors (54) each installed at predetermined specific locations as shown in FIG. 3, or may be configured in the form of a reflector array in which three retroreflectors (54) are arranged in a predetermined arrangement and formed integrally as shown in FIG. 6.

[0104] Furthermore, it should be noted that the indoor positioning system (50) using reflected light according to an embodiment of the present invention may be configured to include a reflector array in which a plurality of retroreflectors (54) formed in different shapes, such as a triangle, a square, a circle, a cross, etc., are arranged in a predetermined number and shape, and the present invention can be configured in various ways as needed.

[0105] That is, referring to FIG. 7, FIG. 7 is a drawing schematically showing another configuration example of a retroreflector (54) applied to a reflector array (51) of an indoor positioning system (50) using reflected light according to an embodiment of the present invention.

[0106] Here, in Fig. 7, the left side shows an example of a configuration in the form of a reflector array in which each retroreflector is implemented in a different shape, and the right side shows the results of detecting the reflector array using an IR camera.

[0107] As shown in FIG. 7, the above-described retroreflector (54) may be configured to be formed in different shapes, such as a circle, a triangle, a square, or a cross, by using a reflective tape (film) such as a corner cube retroreflector (CCR) of a single prism type, a prism reflective tape of a prism array type, or a glass bead reflective tape of a micro glass bead type, for example, and to detect the reflector array through the shape of each reflector element using an infrared camera or the like and to identify the ID of each reflector element.

[0108] Alternatively, the above-described reflector array (51) may be configured to modulate the reflected light of each reflector element by using a reflector that combines a reflector and a light modulator, such as a retroreflector of the MRR (modulated retroreflector) type, so that the reflector can be identified. It should be noted that the present invention can be applied to various types of retroreflectors without any particular limitation.

[0109] Additionally, the absolute position (coordinate) information of each retroreflector (54) may be stored in advance in the server (53) and configured to be transmitted to the user terminal (52) of the user when the user's position is measured.

[0110] Alternatively, the absolute position (coordinate) information of each retroreflector (54) may be stored in a user terminal (52) or a separate storage means instead of the server (53), or may be configured to be directly input from a user or the outside. Therefore, it should be noted that the present invention is not necessarily limited to the configuration presented in the embodiments of the present invention, but may be configured by various modifications and changes as needed by those skilled in the art within a scope that does not deviate from the spirit and essence of the present invention.

[0111] In addition, the above-mentioned reflector array (51) can be installed inside a building such as an airport, a shopping mall, or a department store, just like the existing system shown in Fig. 1, and there are no special restrictions on the installation location, but it is preferable to install it on the ceiling inside the building so that the optical signal is not blocked by pedestrians, furniture, etc.

[0112] Furthermore, in order to determine the three-dimensional position of the user, it is desirable to install a reflector array consisting of three or more retroreflectors (54), but if the height of the user (position on the z-axis) is known, the exact position can be determined even with a reflector array consisting of two retroreflectors (54).

[0113] More specifically, referring to FIG. 8, FIG. 8 is a block diagram schematically showing the overall configuration of an indoor positioning system (50) using reflected light according to an embodiment of the present invention.

[0114] As shown in FIG. 8, an indoor positioning system (50) using reflected light according to an embodiment of the present invention may be configured to include a reflector array unit (51), a user terminal (52), and a server (53). At this time, the user terminal (52) is broadly divided into an optical signal transmitting unit (72) configured to perform processing for transmitting an optical signal, an optical signal receiving unit (72) configured to perform processing for receiving an optical signal reflected through the reflector array unit (51), a reflector detecting unit (73) configured to perform processing for identifying each reflector of the reflector array unit (51) based on the received optical signal, a distance calculating unit (74) configured to perform processing for calculating a distance between the user terminal (72) and the reflector array unit (51) based on reception information of the optical signal, and a position determining unit (75) configured to perform processing for calculating an absolute position of the user terminal (52) using the calculated distance information and the absolute position information of each reflector, and the processing processes of each of the above units. It can be configured to include a data storage unit (76) that performs processing to store various data obtained through processing results according to predetermined settings.

[0115] Here, the user terminal (52) described above may be configured with dedicated hardware that is linked to the server (53), but preferably, it may be configured by installing a dedicated application that performs processing as described below on an information and communication terminal that can be carried by an individual, such as a smart phone or tablet PC, or an information processing device such as a PC or laptop, and thereby, it may be configured with a simpler configuration and lower cost without the need to implement separate hardware.

[0116] In addition, it should be noted that the user terminal (52) described above is not necessarily limited to the configuration presented in the embodiment of the present invention, and is not particularly limited in its specific configuration as long as it includes a sensor capable of receiving the intensity, brightness, saturation, etc. of reflected light and a sensor capable of calculating a distance from a transmitted and received optical signal.

[0117] More specifically, first, the above-mentioned optical signal transmission unit (71) can be configured to perform processing for transmitting an optical signal such as infrared, visible light, laser, or a signal modulated with such an optical signal.

[0118] In addition, the above-described optical signal receiving unit (72) may be configured to perform processing such as measuring information such as the intensity and reception time of an optical signal received according to predetermined settings using an optical signal receiving sensor including, for example, an infrared camera, a depth camera, a ToF (Time of Flight) sensor, etc., and transmitting the information to a reflector detection unit (73) and a distance calculation unit (74).

[0119] That is, the above-described optical signal transmitter (71) and optical signal receiver (72) can be configured using an information and communication device such as a ToF camera or a smartphone having a ToF camera function.

[0120] In addition, the above-described reflector detection unit (73) can be configured to detect the reflector array using the intensity, brightness, saturation, shape, etc. of the reflected light based on the optical signal received through the optical signal receiving unit (72), and to perform a process of identifying each reflective surface (i.e., each retroreflector (54)) using the arrangement information of the reflector array stored in advance in the server (53).

[0121] That is, referring to FIGS. 9 to 11, FIGS. 9 to 11 are conceptual diagrams schematically showing a process of detecting a reflector array and identifying each reflector in a reflector detection unit (73) of an indoor positioning system (50) using reflected light according to an embodiment of the present invention.

[0122] More specifically, the process of identifying a reflector can detect an array of reflectors by first measuring the intensity of an optical signal from an IR image captured using a TOF camera, as shown in Fig. 9, and detecting a point where the intensity change in the amount of light is large (a point where the brightness change is large).

[0123] At this time, as shown in Fig. 10, since the TOF image contains distance information for each pixel, when the reflector array is detected, distance information for each reflector can be obtained.

[0124] In addition, as shown in Fig. 11, when the reflector array is detected from the optical signal received through the optical signal receiving unit (72), information on the relative distance (a', b', c') between the reflectors can be obtained from each detected reflector, and information on the actual distance (a, b, c) between each reflector can be known based on the absolute position information of the reflector array stored in advance in the server (53).

[0125] Therefore, by comparing (matching) the relative distances (a', b', c') between the reflectors obtained as described above with the actual distances (a, b, c) between each reflector, it is possible to identify which reflector each reflector corresponds to, and thereby identify which reflector the distance information of each reflector is from.

[0126] Furthermore, the above-described distance calculation unit (74) can be configured to perform processing to calculate the distance from the user terminal (52) to the reflector array unit (51) based on the reception information of the optical signal received through the optical signal receiving unit (72), as described below.

[0127] In addition, the above-mentioned position determination unit (75) may be configured to perform processing to calculate the absolute position of the user terminal (52) using a triangulation technique or the like based on the distance information calculated through the distance calculation unit (74) and the absolute position information of each reflective surface of the reflector array stored in the server (53) or data storage unit (76).

[0128] That is, as a method of calculating distance information using the received optical signal as described above, first, there is, for example, the TOF (Time of Flight) method that calculates distance using the difference between the transmission and reception times.

[0129] More specifically, when the time point at which the light signal is output is t1, the time point at which it is detected is t2, and the speed of light is c, the distance can be expressed as in [Mathematical Formula 1] below.

[0130] [Mathematical Formula 1]

[0131]

[0132] Alternatively, another method is to calculate the distance using the carrier phase measurement of the received reflected light signal, and the carrier phase measurement of the reflected light signal can be modeled as in [Mathematical Formula 2] below.

[0133] [Equation 2]

[0134]

[0135] Next, if it is possible to determine an unknown number within a carrier measurement value as described above, distance information can be obtained from a carrier phase measurement value, and the determination of the unknown number can be made using a method used in CDGPS (Carrier-phase Differential GPS), RTK, PPP, etc. of a satellite navigation system.

[0136] As mentioned above, for example, the transmission / reception time difference, TOF, carrier phase measurement, etc. can be used as a method for calculating the distance. It should be noted that the detailed description of the distance calculation method or triangulation technique is omitted here because it is obvious to those skilled in the art through the contents of the prior art.

[0137] That is, existing indoor positioning systems and methods have problems such as difficulty in building infrastructure, continuous power consumption, signal interference problems due to radio wave characteristics (BLE), and limitations on the number of multiple users (UWB) depending on the distance measurement method, etc., because distance measurement is performed using radio wave signals such as Wi-Fi, Bluetooth (BLE), and UWB. However, according to the present invention, as described above, the so-called 'one-way ranging' method of distance measurement processing is performed using the reflective properties of light and a retroreflector, so that distance calculation is possible using only a ToF sensor, and thus, compared to the past, high accuracy is achieved at a low cost, and since there is no limitation on the number of multiple users, versatility and practicality can be increased.

[0138] As described above, an indoor positioning system (50) using reflected light according to an embodiment of the present invention can be implemented, and with reference to FIG. 12, FIG. 12 is a flowchart schematically showing the overall processing process of an indoor positioning method using an indoor positioning system (50) using reflected light according to an embodiment of the present invention shown in FIGS. 3 to 11.

[0139] As shown in FIG. 12, the indoor positioning method using reflected light according to an embodiment of the present invention is broadly divided into an optical signal transmission / reception step (S10) in which an optical signal is transmitted through an optical signal transmission unit (71) of a user terminal (52), and an optical signal reflected through each retroreflector (54) of a reflector array unit (51) is received through an optical signal reception unit (71) of the user terminal (52), a reflector detection step (S20) in which a process of detecting a reflector array based on the received optical signal and identifying each reflective surface (i.e., a retroreflector (54)) is performed through a reflector detection unit (73) of the user terminal (52), a distance calculation step (S30) in which a process of calculating a distance from the user terminal (52) to each reflective surface based on the identification result of the reflector detection step (S20) and the reception information of the optical signal is performed through a distance calculation unit (74) of the user terminal (52), The process of determining the location of the user terminal using triangulation techniques, etc. based on the distance calculated through the distance calculation step (S30) and the location information of each reflective surface may be configured to include a location determination step (S40) performed through the location determination unit (75) of the user terminal (52).

[0140] Here, the indoor positioning system (50) and method using reflected light according to an embodiment of the present invention may be configured to transmit various data including the user's location, movement distance, movement time, etc. by time, obtained through the processing and results of each step described above, to a server (53), although not shown, to build a database related to the user's location and movement for each user, and to perform processing to provide corresponding information in a customized manner according to the user's request received through the user terminal (52).

[0141] In addition, in the above-described embodiment of the present invention, the present invention has been described by taking as an example a case where the absolute position information of each retroreflector (54) of the reflector array (51) is stored in the server (53), but the present invention is not necessarily limited to the contents presented in the embodiment, that is, the present invention may be configured so that, for example, the above-described absolute position information is stored in the data storage unit (76) of the user terminal (52) or a separate storage means instead of the server (53), or is directly input from the user or the outside, and therefore, it should be noted that the present invention can be configured by modifying and changing it in various ways as needed by those skilled in the art within a scope that does not depart from the spirit and essence of the present invention.

[0142] Moreover, in the above-described embodiment of the present invention, the present invention has been described by taking as an example a case where a user's location is determined for a single indoor space, but in addition, according to the present invention, it can be configured to accurately determine a user's location even for a building having multiple floors or independent spaces, such as a high-rise building.

[0143] That is, for example, by forming a plurality of reflector arrays having different arrangement shapes to form a reflector array section (51), and installing different reflector arrays for each floor or space, and storing location information for each reflector array in a server (53) or a separate database, etc., it is possible to easily determine where and on which floor a user is located by identifying the reflector array through a user terminal (52).

[0144] Alternatively, it should be noted that the present invention can be configured in various ways as needed, such as by providing predetermined specific identification information to each reflector array instead of forming each reflector array differently, so that each reflector array can be identified.

[0145] From the above-described configuration, according to the present invention, the optical signal transmitter and receiver required for an indoor positioning system using reflected light, the image sensor required for detecting the reflector array, etc. can be purchased at a relatively low price, and the configuration and installation process of the reflector array are also simple, so that the manufacturing and installation costs of the entire system are reduced, and a low-cost indoor navigation system can be easily implemented compared to the existing one.

[0146] In addition, according to the present invention, since information and communication devices equipped with basic sensors necessary for constructing an indoor positioning system using reflected light, such as, for example, a smartphone equipped with a TOF camera function, have been widely distributed recently, if the user terminal (52) is configured as a smartphone equipped with a TOF camera function, an indoor positioning system can be constructed more simply and easily by simply installing a retroreflector array in an indoor environment, thereby further increasing the accessibility and usability of the indoor positioning system.

[0147] In addition, according to the present invention, an accurate and precise indoor positioning system of cm level can be easily implemented with a simpler configuration and lower cost than before through distance information calculated using TOF and carrier phase measurement, etc.

[0148] Furthermore, according to the present invention, a location information service providing system and method capable of providing location information of a user both indoors and outdoors can be easily implemented by being configured to determine the location of a user both outdoors and indoors in combination with existing location tracking devices and methods such as GPS.

[0149] In addition, according to the present invention, as described above, by using reflected light, it is configured to accurately track the location of a user indoors with a simpler configuration and at a lower cost, so that, for example, by installing a reflector array in an indoor space, even in a situation where securing visibility is difficult in an emergency situation such as a fire, various information such as the location of the user or an escape route can be quickly and accurately identified and provided, and thus it has the advantage of being widely applicable in various fields such as firefighting and disaster relief.

[0150] As described above, an indoor positioning system (50) and method using reflected light according to an embodiment of the present invention can be implemented, and subsequently, the actual performance of the indoor positioning system (50) and method using reflected light according to an embodiment of the present invention configured as described above is described as verified through experiments.

[0151] That is, in order to verify the actual performance of the indoor positioning system (50) and method using reflected light according to the embodiment of the present invention configured as described above, the inventors implemented the indoor positioning system (50) using reflected light as described above and performed position measurement in a laboratory environment.

[0152] More specifically, referring to FIGS. 13 to 15, FIG. 13 is a drawing schematically showing an experimental environment of a verification experiment for verifying the actual performance of an indoor positioning system (50) and method using reflected light according to an embodiment of the present invention, and FIGS. 14 and 15 are drawings each showing the experimental results of a verification experiment for verifying the actual performance of an indoor positioning system (50) and method using reflected light according to an embodiment of the present invention.

[0153] As shown in Fig. 13, the inventors installed a reflector array in the room of Room 501, Building 312, Seoul National University as an experimental site, and used Microsoft's Azure Kinect (applied as an infrared camera, TOF sensor) as a measuring device for the experiment.

[0154] At this time, the distance between the reflector array and the experimental equipment was 1.2 m to 2.4 m, the number of reflectors in the reflector array was 2, and the distance between the reflectors in the reflector array was 12 cm. Position measurements were performed at each predetermined measurement point while moving along the circle indicated by the dotted line in Fig. 12, and for accuracy analysis, Horizontal Pos.RMSE(2-Dim.) was applied to calculate the horizontal root mean square error for each measurement point.

[0155] As a result of the experiment, as shown in FIGS. 14 and 15, the average error was measured to be at the level of 1.32 cm. Therefore, from these results, it can be confirmed that the indoor positioning system (50) and method using reflected light according to the embodiment of the present invention can be put to practical use as a cm-level high-accuracy indoor positioning system.

[0156] In addition, the above-mentioned Azure Kinect device can be replaced with a smartphone equipped with a TOF camera function, and therefore, the present invention has the advantage of enabling the construction of a low-cost indoor positioning infrastructure since an indoor navigation system can be constructed by simply installing a ToF IR camera and a reflector array.

[0157] Therefore, as described above, an indoor positioning system and method using reflected light according to an embodiment of the present invention can be implemented, and thereby, according to the present invention, a reflector array made of retroreflectors having the same incident angle and reflection angle of an optical signal and an optical signal transmitter / receiver such as a TOF camera can be used to accurately track the location of a user indoors with a simpler configuration and lower cost compared to existing systems and methods, and in addition, various user location-based services requiring a high-accuracy indoor positioning system, such as autonomous parking functions in underground parking lots, or wayfinding, location-based advertising, and entertainment in wide indoor spaces such as large shopping malls, can be implemented and provided more easily, and at the same time, it has the advantage of being widely applicable to various fields such as firefighting and disaster relief.

[0158] Hereinafter, the detailed contents of the indoor positioning system and method using reflected light according to the present invention have been described through the embodiments of the present invention as described above, but the present invention is not limited to the contents described in the embodiments above, and therefore, it will be obvious that the present invention can be modified, changed, combined, and replaced in various ways by a person having ordinary knowledge in the technical field to which the present invention pertains according to design needs and other various factors.

[0159]

[0160] [Explanation of symbols]

[0161] 10. Indoor positioning system using reflected light

[0162] Ra, Rb, Rc. Reflection surfaces

[0163] R. Reflection

[0164] S. Server

[0165] T. User terminal

[0166] 301. The Light Transmission Department

[0167] 302. Optical receiver

[0168] 303. Distance Calculation Unit

[0169] 304. Storage

[0170] 305. Positioning unit

[0171] 50. Indoor positioning system using reflected light

[0172] 51. Reflector array

[0173] 52. User terminal

[0174] 53. Server

[0175] 54. Retroreflector

[0176] 71. Optical signal transmitter

[0177] 72. Optical signal receiver

[0178] 73. Reflector detection unit

[0179] 74. Distance Calculation Unit

[0180] 75. Positioning unit

[0181] 76. Data storage

Claims

1. In an indoor positioning system using reflected light, A reflector array comprising a reflector array in which a plurality of retroreflectors having the same incident angle and reflection angle of an optical signal are arranged in a predetermined number and interval; and An indoor positioning system using reflected light, characterized in that it comprises a user terminal configured to perform processing for determining a user's location using reflected light received through each of the reflectors of the above reflector array.

2. In paragraph 1, The above reflector array is, An indoor positioning system using reflected light, characterized in that each of the above retroreflectors is installed at a predetermined location to form the above reflector array.

3. In paragraph 1, The above reflector array is, An indoor positioning system using reflected light, characterized in that each of the above retroreflectors is arranged in a predetermined array so that the integrally formed reflector array is installed at a predetermined location.

4. In paragraph 1, The above reflector array is, By including a plurality of retroreflectors formed in different shapes using a reflective tape (film) including a corner cube retroreflector (CCR) of a single prism type, a prism reflective tape of a prism array type, or a glass bead reflective tape of a micro glass bead type, An indoor positioning system using reflected light, characterized in that it detects an array of reflectors through the shape of each retroreflector and is configured to identify each retroreflector.

5. In paragraph 1, The above indoor positioning system, An indoor positioning system using reflected light, characterized in that it further comprises a server in which location information for each reflector of the reflector array is stored in advance and processing is performed to transmit the corresponding information to the user terminal upon request of the user terminal.

6. In paragraph 1, The above indoor positioning system, An indoor positioning system using reflected light, characterized in that location information for each reflector of the above reflector array is stored in advance in the user terminal.

7. In paragraph 1, The above user terminal, An optical signal transmitting unit configured to perform processing for transmitting an optical signal according to predetermined settings; An optical signal receiving unit configured to perform processing of receiving an optical signal reflected through the above reflector array; A reflector detection unit configured to perform a process of identifying each reflector of the reflector array based on a received optical signal; A distance calculation unit that performs processing to calculate the distance between the user terminal and the reflector array unit based on the reception information of the optical signal; A position determination unit that performs processing to calculate the position of the user terminal using the calculated distance information and the position information of each reflector; and An indoor positioning system using reflected light, characterized in that it comprises a data storage unit configured to perform processing for storing various data obtained through the processing and processing results of the optical signal transmitter, the optical signal receiver, the reflector detection unit, the distance calculation unit, and the position determination unit according to predetermined settings.

8. In paragraph 7, The above user terminal, An indoor positioning system using reflected light, characterized in that it comprises a detection sensor capable of receiving at least one of intensity, brightness, and saturation of reflected light and a distance sensor capable of calculating a distance from the transmitted and received optical signal.

9. In paragraph 7, The above user terminal, An indoor positioning system using reflected light, characterized in that it is configured by installing a dedicated application on a personal information and communication device including a smartphone having a ToF (Time of Flight) camera function.

10. In paragraph 7, The above reflector detection unit, Based on the optical signal received through the optical signal receiving unit, the reflector array is detected using at least one piece of information among the intensity, brightness, saturation, and shape of the reflected light according to a predetermined setting, An indoor positioning system using reflected light, characterized in that the system is configured to perform a process of identifying each reflector by comparing the relative distance between each reflector of the detected reflector array and the actual distance between each reflector based on the location information of the reflector array stored in advance.

11. In paragraph 7, The above distance calculation unit is, An indoor positioning system using reflected light, characterized in that the system is configured to perform processing for calculating the distance from the user terminal to the reflector array using the TOF (Time of Flight) method, which calculates the distance using the difference in transmission and reception times based on the reception information of the optical signal received through the optical signal receiving unit.

12. In paragraph 7, The above distance calculation unit is, An indoor positioning system using reflected light, characterized in that it is configured to perform processing for calculating the distance from the user terminal to the reflector array using the carrier phase measurement value of the received reflected light signal based on the reception information of the optical signal received through the optical signal receiving unit.

13. In paragraph 7, The above positioning unit, An indoor positioning system using reflected light, characterized in that it is configured to perform processing for calculating the absolute position of the user terminal using a triangulation technique based on distance information calculated through the distance calculation unit and position information of the reflector array stored in advance.

14. In paragraph 7, The above indoor positioning system, Various data including the user's location, movement distance, and movement time by time obtained through each processing process and result of the optical signal transmitter, the optical signal receiver, the reflector detection unit, the distance calculation unit, and the position determination unit are stored in the data storage means according to a predetermined setting and transmitted to a server or an external device to build a database related to the user's location and movement for each user. An indoor positioning system using reflected light, characterized in that processing is performed to provide customized information according to a user request received through the user terminal based on the contents of the database.

15. In paragraph 1, The above indoor positioning system, The above reflector array is configured to include a plurality of reflector arrays having different arrangement forms, or is configured to enable identification of a plurality of reflector arrays by assigning predetermined identification information to each reflector array. By installing different reflector arrays in each indoor space and storing the location information for each reflector array in advance in a server or separate database, and then performing a process to identify the reflector array installed in the corresponding indoor space through the user terminal and determine the location, An indoor positioning system using reflected light, characterized in that it is configured to accurately determine the user's location even in an indoor space comprising multiple floors or rooms.

16. In an indoor positioning method using reflected light, which is configured to determine the location of a user indoors using an indoor positioning system using reflected light as described in any one of claims 1 to 15, An optical signal transmission step in which processing is performed to transmit an optical signal through an optical signal transmission unit of a user terminal of an indoor positioning system using the above reflected light; An optical signal receiving step in which processing is performed to receive an optical signal transmitted through the optical signal transmitting step and reflected from the reflector array of the indoor positioning system through the optical signal transmitting step of the user terminal; A reflector detection step in which a process of detecting a reflector array and identifying each reflector based on an optical signal received in the optical signal receiving step is performed through a reflector detection unit of the user terminal; A distance calculation step in which processing for calculating the distance from the user terminal to each reflector based on the identification result of the reflector detection step and the reception information of the optical signal is performed through the distance calculation unit of the user terminal; An indoor positioning method using reflected light, characterized in that it comprises a position determination step in which processing for determining the position of the user terminal using a triangulation technique based on the distance calculated through the distance calculation step and the position information of each reflective surface is performed through a position determination unit of the user terminal.

17. In paragraph 16, The above method, A database construction step in which various data including the user's location, movement distance, and movement time by time obtained through the processing and results of the optical signal transmission step, the optical signal reception step, the reflector detection step, the distance calculation step, and the position determination step are transmitted to a server or an external device according to predetermined settings to construct a database related to the user's location and movement for each user; and An indoor positioning method using reflected light, characterized in that it further comprises an information provision step in which processing is performed to provide corresponding information in a customized manner according to a user's request received through the user terminal based on the contents of the database constructed through the above database construction step.

18. In a location information service provision system configured to provide location information to users both indoors and outdoors according to the user's location, An outdoor positioning unit configured to perform processing that provides location information of a user outdoors using a location tracking device including a GPS; and A location information service providing system characterized by comprising an indoor location unit configured to perform processing for providing location information of a user indoors using an indoor location system using reflected light as described in any one of claims 1 to 15.

19. A method for providing location information services configured to provide location information to users both indoors and outdoors according to their location. An outdoor positioning step in which processing is performed to provide the user's location information outdoors using a location tracking device including GPS; and A location information service providing method characterized by comprising an indoor location step in which processing is performed to provide location information of a user indoors using an indoor location system using reflected light as described in any one of claims 1 to 15.

Images