KR102294832B1 - Method and system for improving the accuracy of positioning method based on 5g new radio network - Google Patents

Abstract

A method for a base station to improve positioning accuracy based on 5G NR, comprising: transmitting a paging to a terminal; as a response to the paging, a synchronization signal block (SSB) index corresponding to a beam coverage in which the terminal is located Receiving a physical random access channel including, and transmitting the SSB index to a location management function block is a positioning accuracy improvement method comprising the steps of.

Description

5G NR-based positioning accuracy improvement method and system

The present invention relates to a technology for improving positioning accuracy based on 5G NR.

As a positioning technology in a mobile communication wireless network, there are various methods such as E-CID (Enhanced Cell ID), OTDOA (Observed Time Difference Of Arrival), and GPS (Global Positioning System). The most basic method for targeting is E-CID positioning. This method basically acquires location information based on a cell identifier (Cell ID), and narrows the location of the terminal by combining the existing CID method with a Received Signal Strength Indication (RSSI) method. However, there is a disadvantage that the entire range of the cell region corresponds to the position error range. For example, an error of several hundred meters in a city center and several kilometers in a non-city center may occur.

In order to reduce this error, the E-CID method uses the received electric field strength (Reference Signal Received Power, RSRP) or the distance error with the service base station by using the measurement distance difference (Round Trip Time, RTT) between the base station and the terminal. can be minimized. However, the error on the X-axis can be minimized using these values, but there is a limit that the error on the Y-axis cannot be reduced.

The problem to be solved by the present invention is a method and system for improving positioning accuracy by utilizing the SSB index of a beam used for beamforming as location information in order to minimize a location measurement error in a 5G NR-based wireless network is to provide

A method for a base station to improve positioning accuracy based on 5G NR according to an embodiment, the method comprising: transmitting a paging to a terminal; as a response to the paging, a synchronization signal block corresponding to a beam coverage in which the terminal is located (Synchronization Signal) Block, SSB) receiving a physical random access channel including an index, and transmitting the SSB index to a location management function block.

The location management functional block includes at least one of the cell identifier of the base station, the latitude and longitude in which the base station is installed, the address of the base station, information on the SSB indexes assigned to the base station, and the SSB index received from the base station. It can be managed with a database, and the location of the terminal can be measured using the database.

A method for using a location management functional block to improve location positioning accuracy based on 5G NR according to another embodiment, the method comprising: managing location information of synchronization signal block (SSB) indexes allocated to a base station; from the base station Receiving the SSB index transmitted from the terminal, and measuring the location of the terminal using the location information of the SSB indexes and the SSB index.

The location information of the SSB indexes may include at least one of a direction angle for each SSB index, a horizontal beam width for each SSB index, and a vertical beam width for each SSB index, and the SSB index may correspond to a beam coverage in which the terminal is located.

The location information of the SSB indices corresponds to a port of the wireless signal processing device in the base station and each stair where a plurality of repeaters are installed in a building, and the SSB index is a repeater in which the terminal receives a radio signal among the plurality of repeaters. can respond to

5G NR-based positioning accuracy improvement system according to another embodiment, a location management function block (Location Management Function, LMF) for managing location information of a synchronization signal block (Synchronization Signal Block, SSB) indexes, and SSB from the terminal and a base station that receives an index and transmits the SSB index to the LMF, wherein the LMF receives the SSB index transmitted from the terminal from the base station, and uses the location information of the SSB indexes and the SSB index. Measure the location of the terminal.

The SSB index is assigned to the base station and may correspond to a beam coverage in which the terminal is located or may correspond to a repeater receiving a signal from the terminal.

According to the present invention, it is possible to improve the accuracy of a Location Based Service (LBS) by minimizing a location positioning error for a 5G NR-based wireless network target.

In addition, according to the present invention, it is possible to determine the location of the terminal even inside the building, so it is possible to provide an in-building solution by subdividing the floor where the terminal is receiving service.

1 is an explanatory diagram illustrating beam coverage according to an embodiment.
2 is a flowchart of a method for improving positioning accuracy according to an embodiment.
3 is a flowchart of a method of operating a base station according to an embodiment.
4 is an explanatory diagram of a method for improving intra-layer positioning accuracy according to an embodiment.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part "includes" a certain element, it means that other elements may be further included, rather than excluding other elements, unless otherwise stated.

In the present specification, a terminal is a user equipment, a device, a user equipment (UE), a mobile equipment (ME), a mobile station (MS), a mobile terminal (MT), a subscriber station, SS), Portable Subscriber Station (PSS), User Equipment (UE), Access Terminal (AT), etc. It may include all or part of the functionality of a user device or the like.

The terminal of the present specification is a gateway, a base station (BS), an access point (Access Point, AP), a radio access station (Radio Access Station, RAS), a Node B (Node B), an advanced node B (evolved) NodeB, eNodeB), Base Transceiver Station (BTS), Mobile Multihop Relay (MMR)-BS, 5G NB (gNB), etc. can be accessed and connected to a remote server.

In this specification, a base station means a 5th generation mobile communication New Radio (NR) base station established by 3GPP, and a 5G radio access network NG-RAN (Next Generation-Radio Access Network) is connected and configured with a plurality of gNodeBs. An eNodeB may also be included. In the following specification, the base station of 5G NR is collectively referred to as gNB.

Embodiments of the present invention may be supported by standard documents related to a 3rd Generation Partnership Project (3GPP) 5th generation (5G) system, such as Study on Architecture for Next Generation System (FS_NextGen). That is, steps or parts not described in order to clearly reveal the technical spirit of the present invention among the embodiments of the present invention may be supported by the document. In addition, all terms disclosed in this document may be explained by the standard document.

Meanwhile, a 5G NR-based wireless communication system basically applies a beamforming technology. For this, a beam sweeping technique must be implemented.

Synchronization Signal Block (hereinafter referred to as 'SSB') is a Sync Signal (SS), Physical Broadcast Channel (PBCH), etc. for a UE to acquire synchronization in a 5G wireless network or to secure basic cell information It is a unit block that provides important information of

Meanwhile, the SSB is repeatedly transmitted at a specific time and a specific frequency band according to a preset period. For example, when transmitting a maximum of 8 SSBs, only one SSB is transmitted when transmitting the entire cell, and when beam sweeping is performed for beamforming, SSBs can be transmitted in a maximum of 8 time domains.

In this case, each SSB has a unique SSB index, and the SSB index is independently transmitted at different timings when beam sweeping is performed. Each beam according to the SSB index is radiated with a sharp beam angle, and the terminal can determine the SSB index through analysis of the transmission time. Therefore, it is possible to determine the location of the terminal through the SSB index.

Hereinafter, a position measuring method according to an embodiment of the present invention will be described in detail with reference to the drawings.

1 is an explanatory diagram illustrating beam coverage according to an embodiment.

Referring to FIG. 1 , the gNB 200 may use a plurality of beams and allocate coverage of each beam separately. For example, when the gNB 200 uses 8 beams, the beam angle may be different for each SSB index to be emitted.

At this time, when the gNB 200 assigns an SSB index according to the beam coverage, each SSB index is transmitted in a state in which the geographic transmission range is determined. Therefore, the terminal 100 can determine the SSB index of the beam coverage in which the terminal 100 is located through the analysis of the transmission time, and the error can be minimized by correcting the position for the direction angle of the beam using the SSB index. .

On the other hand, the position error correction for the radius may use the LTE quality parameter. For example, Reference Signal Received Power (RSRP) or Round Trip-Dealy (RTD) may be used.

2 is a flowchart of a method for improving positioning accuracy according to an embodiment.

Referring to FIG. 2 , the location measurement system 1000 includes a terminal 100 , a gNB 200 , an access and mobility management function block 300 , and a location management function block 400 . The terminal 100 is a device for transmitting a paging and physical random access channel (hereinafter, collectively referred to as 'PRACH') to the gNB 200 through a wireless network. The gNB 200 stores the SSB index received from the terminal 100 and transmits it to the Location Management Function (hereinafter referred to as 'LMF') 400 . The LMF 400 receives the location information message from the gNB 200 and measures the location of the terminal 100 based on it, and performs the operation described in the present invention.

The LMF 400 requests a subscriber location service from the Access and Mobility Management Function (hereinafter referred to as 'AMF') 300 (S100).

The AMF 300 transmits a paging signal for performing a location service to the gNB 200 (S110). As the function of the MME is decomposed in the 4G network, the AMF performs a part of the function of a mobility management device (MultiMedia Equipment, MME), and performs registration management, connection management, mobility management, access authentication and authorization, and the like.

The gNB 200 transmits a paging signal to the terminal 100 through a beam (S120). In this case, the gNB 200 may transmit the SSB in one or more beam directions. Meanwhile, in E-CID, which is one of the positioning techniques using a cell identifier, the location of the UE is estimated through information about the gNB and the cell. In this specification, a method of acquiring information about a gNB and a cell through paging is described, but information about a gNB and a cell may be obtained through registration or other methods as well as paging.

The terminal 100 performs call setup, determines the SSB index corresponding to the currently located beam coverage, and prepares for PRACH transmission (S130). For example, the terminal 100 may measure the strength of the transmission beam of the gNB 200 to determine the transmission beam having the strongest strength, and may determine the corresponding SSB index.

Thereafter, the terminal 100 transmits the determined SSB index to the gNB 200 (S140). In this case, the terminal 100 may perform PRACH to transmit the SSB index to the gNB 200 . For example, when first accessing the gNB 200 or there is no radio resource for signal transmission, the terminal 100 may perform PRACH.

When the terminal 100 transmits the PRACH to the gNB 200 , the terminal 100 also transmits SSB index information corresponding to the beam to which the terminal 100 belongs. Therefore, it is possible to perform positioning using the SSB index value.

The gNB 200 stores the SSB index received from the terminal 100 (S150). The gNB 200 determines with which beam a data service is to be performed based on the received SSB index, and forms a beam according to a beam pattern set when transmitting and receiving data to the terminal 100 . Thereafter, when the session to the terminal 100 is maintained, the gNB 200 continuously tracks the SSB index value corresponding to the terminal 100 . Accordingly, it is possible to track the location of the terminal 100 .

Thereafter, in order to determine the location of the terminal 100 , the terminal 100 , the gNB 200 , the AMF 300 , and the LMF 400 perform a call processing procedure ( S160 ).

The gNB 200 transmits the SSB index stored in the LMF 400 (S170).

The LMF 400 receives the SSB index from the gNB 200 and performs positioning of the terminal 100 (S180). The method performed by the LMF 400 may be E-CID, OTDOA, GPS, etc. as described above, and since these techniques are already known, detailed description thereof will be omitted.

3 is a flowchart of a method of operating a base station according to an embodiment.

Referring to FIG. 3 , the gNB 200 , which is a base station for 5G NR, receives a location service request from the LMF 400 ( S200 ). Specifically, when the LMF 400 requests a subscriber location service from the AMF 300 , the AMF 300 then transmits a paging to the gNB 200 so that the gNB 200 receives the service request.

The gNB 200 transmits a paging to the terminal 100 (S210). When the terminal 100 is in the idle mode, the gNB 200 may transmit a paging and receive a PRACH in response thereto.

The gNB 200 receives the PRACH including the SSB index information from the terminal 100 (S220). The terminal 100 determines the SSB reception index, and transmits the PRACH to the gNB 200 in response to the paging. For example, referring to FIG. 1 , since the terminal 100 is located in the beam coverage of the SSB index 0, it transmits the information of the SSB index 0 when transmitting the PRACH to the gNB.

Thereafter, in order to determine the location of the terminal 100 , the terminal 100 , the gNB 200 , the AMF 300 , and the LMF 400 perform a call processing procedure.

The gNB 200 transmits the received SSB index to the LMF 400 (S230). Also, the gNB 200 may manage the secured SSB index.

Thereafter, the LMF 400 performs positioning of the terminals. In this case, the method performed by the LMF 400 may be E-CID, OTDOA, GPS, etc. utilizing a cell identifier, and since these techniques are already known, detailed description thereof will be omitted.

Meanwhile, the LMF 400 may store and manage the SSB index value corresponding to each cell as a database. The location information managed by the database may include information on a beam transmission angle, a vertical width, a horizontal width, and the like of a beam according to an SSB index. That is, the database for location positioning managed by the LMF 400 may include the contents shown in Table 1.

field item Contents Cell Identifier (ID) Unique base station identifier used in mobile communication network (sector unit) latitude, longitude Latitude and longitude where the mobile communication base station is installed, information inserted by the base station operator and can be obtained from the base station GPS receiving board address Address where the mobile communication base station is installed, information inserted by the base station operator SSB index For example, a value assigned from 0 to n Direction angle by SSB index Beam transmission angle according to SSB index Horizontal beam width by SSB index Horizontal width of each beam when sweeping Vertical beam width by SSB index Vertical width of each beam when sweeping

On the other hand, the technology of using the SSB index proposed by the present invention to determine the location of the terminal 100 can be applied even inside a building. In the case of the wireless signal processing unit (remote unit, hereinafter, collectively referred to as 'RU') 210 in the general gNB 200, since beamforming is impossible, one beam is used. In this case, since the number of SSB indexes is the same as the number of beams, it is one. The present invention proposes a technique for assigning a different SSB index value to each port by using that the port of the RU 210 is branched for each stair. Hereinafter, it will be described in detail with reference to FIG. 4 .

4 is an explanatory diagram of a method for improving intra-layer positioning accuracy according to an embodiment.

Referring to FIG. 4 , in order to perform an indoor mobile communication service, the RU 210 in the gNB 200 is connected to the repeater 500, in which case the RU 210 may have 4 or 8 ports. . In this specification, an RU for repeater connection having 8 communication ports will be described as an example.

On the other hand, in order to provide an in-building solution by subdividing the floor on which the terminal 100 is receiving a service, the present invention provides a subdivision of the location of the terminal 100 even when using one beam, the RU 210 We propose a method of assigning different SSB index values to each port of

The LMF 400 assigns a different SSB index according to the location of each layer at which the port of the RU 210 is branched. That is, the location information of the SSB index may be set by matching the port of the RU 210 in the gNB 200 to each floor where the plurality of repeaters 500 are installed in the building. For example, SSB index 0 to SSB index 8 may be sequentially assigned to the RU 210 having 8 ports in the order of port numbers. As another example, an SSB index may be assigned to correspond to the stairs of a building.

Thereafter, the IF signal or RF signal transmitted through the RU 210 of the gNB 200 is introduced into the repeater 500 , and the repeater 500 transmits the RF signal.

Thereafter, the terminal 100 transmits the PRACH including the SSB index to the gNB 200 . That is, the SSB index transmitted by the terminal corresponds to a repeater that the terminal 100 receives a radio signal from among a plurality of repeaters 500 installed in a building. For example, when the terminal is located on the 4th floor, the port entering the repeater 500 on the 4th floor is given the SSB index 4, so the terminal transmits the PRACH including the SSB index 4 to the gNB 200 .

Thereafter, as described in FIG. 3 , the gNB 200 transmits the SSB index to the LMF 400 . Also, the gNB 200 may manage the secured SSB index.

The LMF 400 may perform positioning using the cell identifier and the SSB index received from the gNB 200 , and may determine the stairs in the building where the terminal 100 is located. A process in which the terminal 100 transmits a PRACH to the gNB 200 and a subsequent process are the same as in FIG. 4 , and thus a description thereof will be omitted.

Meanwhile, the LMF 400 may store and manage the information received from the gNB 200 as a database, and the database for positioning may include the contents shown in Table 2.

field item Contents Cell Identifier (ID) Unique base station identifier used in mobile communication network (sector unit) latitude, longitude Latitude and longitude where the mobile communication base station is installed, information inserted by the base station operator and can be obtained from the base station GPS receiving board address Address where the mobile communication base station is installed, information inserted by the base station operator SSB index For example, a value assigned from 0 to n Location by SSB index Information corresponding to the SSB index according to buildings and floors

According to the present invention, it is possible to improve the accuracy of a location-based service by minimizing a location positioning error for a 5G NR-based wireless network target.

In addition, according to the present invention, the location of the terminal can be grasped even inside the building, so it is possible to provide an in-building solution by subdividing the floor where the terminal is receiving service.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improved forms of the present invention are also provided by those skilled in the art using the basic concept of the present invention as defined in the following claims. is within the scope of the right.

Claims (7)

A method for improving the accuracy of in-building positioning based on 5G NR, comprising:
The base station transmitting a paging to the terminal,
Receiving, by the base station, a physical random access channel including a specific synchronization signal block (SSB) index from the terminal as a response to the paging;
transmitting, by the base station, the specific SSB index included in the physical random access channel to a Location Management Function (LMF); and
determining, by the LMF, a specific stair corresponding to the specific SSB index by using the location information of the SSB indices assigned to the stair in the building, and determining that the terminal is located on the specific stair
A method for improving positioning accuracy, comprising: In claim 1,
The LMF further comprises the step of managing a database including the cell identifier of the base station, the latitude and longitude in which the base station is installed, the address of the base station, and the location information of the SSB indexes assigned to the base station. How to improve accuracy. delete delete In claim 1,
The location information of the SSB indexes is
Including different SSB indexes assigned to a plurality of repeaters in the building, and floor information of the building in which the plurality of repeaters are installed,
The plurality of repeaters are connected to the radio signal processing apparatus of the base station,
The specific SSB index is an index assigned to a repeater through which the terminal receives a radio signal among the plurality of repeaters. As a 5G NR-based in-building positioning accuracy improvement system,
A location management function block (Location Management Function, LMF) for managing location information of synchronization signal block (SSB) indexes, and
A base station receiving a specific SSB index from the terminal and transmitting the specific SSB index to the LMF,
The LMF is
The base station receives the SSB index transmitted by the terminal, and uses the location information of the SSB indexes assigned to the stairs in the building to identify a specific stair corresponding to the specific SSB index, and the terminal to the specific stair Positioning accuracy improvement system that determines that it is located. In claim 6,
The specific SSB index is an index assigned to a repeater that receives a signal from the terminal among a plurality of repeaters, positioning accuracy improvement system.

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