KR20180045727A - Method and Apparatus for Selecting Cell based on Service - Google Patents

Abstract

An embodiment of the present invention relates to a method and apparatus for satisfying service requirements by allowing a terminal to access a cell satisfying the service requirements to be operated by selecting a proper cell, initial connection, reconnection, and handover for each terminal by allowing the terminal to recognize wireless communication technology and a frequency with a different characteristic in a 5G network. Accordingly, the present invention can efficiently use a network resource.

Description

[0001] The present invention relates to a method and apparatus for selecting a cell in a mobile communication system,

The present invention relates to a method and an apparatus for selecting a suitable cell according to a type of a service to be performed by a terminal in a mobile communication system.

The contents described below merely provide background information related to the present embodiment and do not constitute the prior art.

Recently, efforts have been made to develop an improved 5th-generation (5G) communication system to meet the increasing demand for wireless data traffic after commercialization of 4th generation (4G) communication system .

The 5G communication system includes both LTE evolution technology and new radio access technology (New RAT) and also provides a standard that can be used in all frequency bands above 6GHz and below. In the case of New RAT, it can be used not only in the existing IMT frequency band but also in a wide channel bandwidth in the millimeter wave band, and it will be a form of increasing the maximum user data rate and the capacity per unit area in a small cell in an indoor or specific dense area .

The user scenarios considered in the 5G communication system are largely divided into mobile ultra broadband (eMBB), ultra-reliable & low latency communications (uMTC) , massive machine type communication). To this end, 5G communication systems are required to have significantly improved performance and new capabilities over existing wireless access technologies.

Meanwhile, the network of the 5G communication system is different according to the user scenario according to the frequency band (Above 6GHz, Below 6GHz), subcarrier spacing, frequency objective (PS-LTE, Enterprise, B2C Subscriber) . According to the network characteristics of the 5G communication system, a 5G communication system requires a new standard different from the conventional 4G communication system. For example, there is a need for a technique for allowing a terminal to recognize a frequency different in characteristics in a network of a 5G communication system to enable selection of a suitable cell for each terminal.

The present embodiment allows a terminal to recognize a frequency and a wireless communication technology having different characteristics in a 5G network and to select a suitable cell, a camp-on, a reselection, and a handover for each terminal, The present invention provides a method and apparatus for connecting to a cell satisfying a service requirement to satisfy a service requirement.

In this embodiment, a terminal of a mobile communication system includes: a communication unit for receiving cell-related information including service type information for the neighboring cell from a base station of at least one neighboring cell adjacent to the terminal; A cell management unit for generating a cell-based support service list defining a supportable service for each of the neighboring cells based on the cell-related information; And a cell selector for determining a connection priority cell among the neighbor cells based on the cell-by-cell support service list.

According to another aspect of the present invention, there is provided a method of selecting a cell of a terminal in a mobile communication system, the method comprising: receiving cell-related information including service type information on the neighboring cell from at least one neighboring cell neighboring the terminal; Receiving process; Generating a list of support services for each cell defining a supportable service for each of the neighboring cells based on the cell-related information; And determining a connection priority cell among the neighboring cells based on the cell-by-cell support service list.

As described above, according to the present embodiment, it is possible to prevent time delay and load generation that may be caused in the cell selection process by preventing cell selection that does not meet the requirements required from the terminal in advance, There is an effect that it can be used efficiently.

1 is a block diagram schematically showing a mobile communication system according to the present embodiment.
2 is a block diagram schematically showing a terminal according to the present embodiment.
3 is a flowchart illustrating a cell selection method of a terminal according to the present embodiment.
4 is a flowchart illustrating a handover procedure of a terminal according to the present embodiment.
5 is an exemplary diagram illustrating a transmission format of cell-related information according to the present embodiment.
6 is a view for explaining a difference between a cell reselection method of a terminal and a cell reselection method of a conventional terminal according to the present embodiment.

Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings.

1 is a block diagram schematically showing a mobile communication system according to the present embodiment. 1 is a block diagram of a 5G mobile communication system supporting a variety of user scenarios exceeding the current IMT, for example, an ultra high bandwidth communication service (eMBB), an ultra high reliability / low delay communication service (uMTC) The system environment is illustrated.

1, the mobile communication system according to the present embodiment includes base stations 102, 112 and 122 supporting wireless connection and network connection of the terminal 130 and a terminal 130 for using the network service do.

The base stations 102, 112 and 122 perform functions such as RF transmission, transmission and reception, signal strength, quality measurement, baseband signal processing, and channel card (channel card resource management). That is, the base stations 102, 112, and 122 are transmitters in the network, and perform functions necessary for wireless call processing such as location registration, radio channel assignment, and handoff in the network. 1, there are first to third base stations 102, 112 and 122 in a mobile communication system, and first to third base stations 102, 112 and 122 are connected to first to third cells 100 , 110, 120).

The first to third base stations 102, 112, and 122 according to the present embodiment support different services, and provide frequencies with different characteristics to the terminal 130 located in the cell according to the services they support . 1, the first base station 102 supports an eMBB service such as AR / VR / Hologram using a frequency band of 6 GHz or more, and the second base station 112 utilizes a frequency band of 6 GHz or less to perform Remote Surgery It is assumed that the same URLLC service is supported and the third base station 122 supports the national disaster security service utilizing the public frequency band. In FIG. 1, each of the base stations 102, 112, and 122 supports only a single service. However, the present invention is not limited thereto. For example, each of the base stations 102, 112, and 122 may be implemented in a form capable of supporting a plurality of services according to an embodiment. Although the base stations 102, 112 and 122 support different services in FIG. 1, the base stations 102, 112 and 122 may support the same service.

The first to third base stations 102, 112, and 122 according to the present embodiment include the cell-related information in the radio signal when the terminal 130 is located adjacent to the cell of each base station, and transmit the cell-related information to the terminal 130 . At this time, the cell-related information includes the cell ID and the service type information for the service that can be supported by the corresponding cell. In addition, the cell ID of the other cell (the second cell and the third cell in the case of the first cell) Service type information for supportable services may be further included. The cell-related information may be transmitted to the terminal 130 in a form included on a System Information message broadcasted from the base station.

Each of the first to third base stations 102, 112 and 122 receives a channel quality measurement result (Measurement Report) from the terminal 130 when it is connected to the terminal 130 and operates as a serving base station, And carries out a handover procedure for the terminal 130 based on the measurement result. Meanwhile, in the present embodiment, the base station operating as the serving base station receives the received signal strength information for the cell of the corresponding base station from the terminal 130, and the service of the terminal 130 As the channel quality measurement result.

The terminal 130 is a terminal capable of transmitting and receiving various data via a network according to a key operation of a user. The terminal 130 can be a tablet PC, a laptop, a personal computer (PC) A smart phone, a personal digital assistant (PDA), a mobile communication terminal, or the like. Preferably, the terminal 130 according to the present embodiment may be a terminal supporting the 5G network.

The terminal 130 according to the present embodiment selects optimal frequency information capable of providing a service that the actual terminal 130 is to perform in a 5G mobile communication system environment in which frequencies having different characteristics are mixed, And performs cell tuning and call connection based on the information.

The terminal 130 is connected to a base station (ex: first to third) of at least one neighboring cell (ex: first to third cells 100, 110, and 120) positioned adjacent to a location of the terminal 130 Cell-related information including the service type information for the neighboring cell is received from the base stations 102, 112, and 122, respectively.

The terminal 130 confirms the service type information about the service to be performed by the terminal 130 and supports the service of the terminal 130 among peripheral cells based on the confirmed service type information and the previously received cell related information And determines a specific peripheral cell as a cell of connection priority order. Then, the terminal 130 performs a cell selection or a cell reselection procedure for a specific neighboring cell determined as a connection priority cell.

The terminal 130 according to the present embodiment can additionally receive not only the service type information for the cell of the corresponding base station but also the service type information for other neighbor cells from the base station of at least one neighboring cell as cell related information. In this case, the service type information for other neighboring cells means service type information for cells of other base stations adjacent to the base station, that is, adjacent to a location where the current terminal 130 is located, ≪ / RTI >

The terminal 130 performs a handover procedure for the terminal 130 using the service type information for the other neighboring cells. Meanwhile, a method of determining a connection priority cell and a method of performing a handover procedure based on cell-related information received from a base station of at least one neighboring cell by the terminal 130 will be described with reference to FIG. The operation of each component will be described in more detail in the process of describing the operation of each component.

2 is a block diagram schematically showing a terminal according to the present embodiment.

The terminal 130 according to the present embodiment includes a communication unit 200, a cell management unit 210, a cell selection unit 220, a connection control unit 230 and a handover control unit 240.

The communication unit 200 communicates with an external device, and transmits / receives necessary information for selective cell access of the terminal 130 through the communication unit 200. The communication unit 200 according to the present embodiment includes cell related information including service type information for the neighboring cell from the base station of at least one neighboring cell.

The communication unit 200 can additionally receive not only the service type information but also the service type information for other peripheral cells from the base station of the neighboring cell as the cell related information.

The communication unit 200 transfers the service type information on neighboring cells to the cell management unit 210 and the service type information on neighboring cells to the handover control unit 240.

The cell management unit 210 generates a cell-by-cell support service list defining a supportable service for each of the neighboring cells based on the cell-related information of at least one neighboring cell received through the communication unit 200.

The list of cell-by-cell support services generated through the cell management unit 210 is stored in a memory (not shown) of the terminal 130. On the other hand, the cell-by-cell support service list stored in the memory can be continuously updated based on the cell-related information about neighboring cells collected through the communication unit 200. In another embodiment, the cell-by-cell support service list may be stored in a format that matches the location information of the terminal 130. In this case, the cell management unit 210 may not store the current cell- May provide a corresponding list of supported services for each cell according to the location of the cell.

The cell selection unit 220 determines a connection priority cell among peripheral cells of the terminal 130 based on the cell-by-cell support service list generated by the cell management unit 210.

The cell selector 220 according to the present embodiment selects specific peripheral cells supporting the service that the terminal 130 is currently performing among peripheral cells of the terminal 130 on the basis of the cell- .

For this, the cell selector 220 firstly checks the service type information about the service to be performed by the terminal 130. For example, the cell selector 220 can confirm service type information on a service to be performed by the terminal 130 based on an input signal input according to a key operation of the terminal user.

The cell selector 220 compares the service type information of the identified terminal 130 with the list of support services for each cell and supports the service that the terminal 130 is currently performing among peripheral cells of the terminal 130 A specific peripheral cell is calculated. Thereafter, the cell selector 220 determines the calculated specific peripheral cell as a cell of a connection priority order.

When a plurality of specific peripheral cells supporting the service to be performed by the terminal 130 are calculated, the cell selector 220 may further use any predetermined priority information so that any one of the plurality of specific peripheral cells is connected As a cell of priority. For example, the priority information used as an additional reference after the service information may be selected based on various parameter values such as received signal strength information, a used frequency band, related information about a cell connected to the terminal 130 at a previous time, have. On the other hand, when the base station according to the present embodiment supports a plurality of services, the priority information may be selected based on the weight information of the corresponding base station for each service.

The connection control unit 230 controls to preferentially perform call connection to cells of a connection priority order determined using the cell selection unit 220. [ Meanwhile, the connection control unit 230 according to the present embodiment selectively performs cell selection or cell reselection to cells of the access priority order according to the current state of the terminal 130. [

The handover control unit 240 refers to a device that performs an overall procedure for handover of the terminal 130. [ The handover controller 240 according to the present embodiment performs a handover procedure for the UE 130 using the service type information for neighboring cells in the cell-related information collected for the base station of the neighboring cell.

More specifically, the handover control unit 240 determines whether or not the neighboring cell (s) included in the cell-related information collected from the base station of a specific neighboring cell (hereinafter referred to as a serving cell) And performs a handover procedure for the terminal 130 using the service type information for the terminal 130.

The handover control unit 240 selects a cell capable of supporting the service of the UE 130 among neighbor cells based on the service type information of the other neighbor cells as a target cell as a handover candidate cell.

The handover controller 240 measures received signal strengths of the serving cell and the target cell, and controls the channel quality measurement result based on the received signal strength to be transmitted to the serving cell. The handover control unit 240 periodically measures and reports the received signal strengths of the serving cell and the target cell, or only when the measured values satisfy the conditions given by the base station of the serving cell Can be reported.

Then, the handover control unit 240 controls handover to the target cell when a handover request message from the serving cell is received. In the case of the present embodiment, the handover request message is selectively transmitted from the serving cell only when the handover request message is finally confirmed to support the service of the terminal 130 with respect to the target cell. A detailed description thereof will be given later in Fig.

3 is a flowchart illustrating a cell selection method of a terminal according to the present embodiment.

The terminal 130 receives cell-related information including at least one neighbor cell neighboring the terminal 130 and service type information for the neighboring cell and service type information for neighboring neighbor cells (S302).

Based on the cell-related information received in step S302, the terminal 130 generates a cell-by-cell support service list defining supportable services for each of the neighbor cells (S304).

The terminal 130 confirms the service type information about the service to be performed in the terminal 130 and supports the service of the terminal among neighboring cells based on the confirmed service type information and the list of support services for each cell generated in step S304 The presence of a possible cell is checked (S306).

If it is determined in step S308 that there is a specific peripheral cell supporting the service of the terminal 130 among the peripheral cells according to the result of the check in step S306, the terminal 130 determines the peripheral cell as a cell of connection priority order , A cell selection or cell reselection procedure to the corresponding cell is performed (S310).

The terminal 130 performs a handover procedure for the terminal 130 using the service type information for other neighbor cells in the cell-related information collected in step S302 (S312). In step S312, the terminal 130 uses the service type information for the other neighbor cells in the cell-related information collected from the base station of the serving cell (ex: connection priority cell) connected to the current terminal 130, 130 according to the handover procedure.

The terminal 130 selects a cell capable of supporting the service of the terminal 130 among other neighboring cells as a target cell serving as a handover candidate cell based on service type information of other neighboring cells.

The terminal 130 measures the received signal strength of the serving cell and the target cell, and transmits the measured channel quality measurement result to the serving cell.

Then, the terminal 130 controls handover to the target cell when a handover request message from the serving cell is received.

In FIG. 3, it is described that each process is sequentially executed, but it is not limited thereto. In other words, the present invention can be applied to changing the procedure shown in FIG. 3 or executing one or more processes in parallel. Therefore, FIG. 3 is not limited to the time series.

3 is a block diagram illustrating a cell selection method of a terminal according to an exemplary embodiment of the present invention. Referring to FIG. 3, a cell selection method of a terminal includes a recording medium (CD-ROM, RAM, ROM, memory card, hard disk, magneto- Lt; / RTI >

4 is a flowchart illustrating a handover procedure of a terminal according to the present embodiment. 4, the handover procedure of the terminal 130, which proceeds throughout the terminal 130, the serving base station 400, and the target base station 410, will be described.

The terminal 130 measures a received signal strength of the serving cell and the target cells, and transmits the channel quality measurement result to the serving base station 400 (S402).

In this embodiment, the target cell is determined based on the service type information for other neighbor cells included in the cell-related information received from the serving base station 400 in the process of the terminal 130 performing the cell selection procedure to the serving cell . For example, the terminal 130 may select a cell capable of supporting the service of the terminal 130 among other peripheral cells as a target cell based on the service type information for the other neighboring cells.

In step S402, the UE 130 may periodically measure and report the received signal strengths of the serving cell and the target cell, or may report these values only when the measured values satisfy the conditions given by the serving base station 400 have. To this end, the UE 130 is provided with a configuration message (RRC Connection Reconfiguration message) related to the reporting of the channel quality measurement result from the serving BS 400 prior to step S402.

In step S404, the serving base station 400 determines handover based on the channel quality measurement result reported by the terminal 130, and starts a handover procedure to the target cell for the terminal 130 based thereon. In step S404, the serving base station 400 transmits a call request signal including the service type information for the service currently supported by the serving base station 400 to the target base station 410 in the handover procedure. In step S404, the serving base station 400 transmits the service type information about the service supported by the serving base station 400 to the target base station 410 on the call request signal to be transmitted to the target base station 410, So that the base station 410 can be verified as a base station to be handed over.

When the target base station 410 supports the service corresponding to the service type information received in step S404, the target base station 410 transmits a call response signal including the service type information that can be supported by the target base station 410 to the terminal 130 (S406).

When the target base station 410 receives the call response signal, the target base station 410 performs a handover preparation procedure to the target base station 410 with respect to the mobile station 130 at steps S408 and S410. (Step S412).

Upon receiving the handover request message of step S412, the terminal 130 performs a procedure of establishing a connection to the target cell and establishing a new RRC connection (S414 and S416).

5 is an exemplary diagram illustrating a transmission format of cell-related information according to the present embodiment.

The base station according to the present embodiment transmits cell information to the terminal 130 by including the cell related information in the radio signal when the terminal 130 is positioned adjacent to the cell of each base station. At this time, the cell-related information includes the cell ID and the service type information for the service that can be supported by the corresponding cell. In addition, the cell ID of the other cell located adjacent to the location where the terminal 130 is located, Service type information for a possible service may be further included.

The cell-related information may be transmitted to the terminal 130 in a form that is included on a System Information message broadcasted from the base station to the terminal 130, as shown in FIG.

6 is a view for explaining a difference between a cell reselection method of a terminal and a cell reselection method of a conventional terminal according to the present embodiment.

Meanwhile, FIG. 6 illustrates a format of a system information message broadcasted from a base station to a terminal 130 in order to describe a conventional cell reselection method of a terminal.

As shown in FIG. 6, according to the conventional scheme, the UE 130 performs a cell reselection procedure based on frequency and cell priority information described on a System Information message broadcast from a base station. In contrast, according to the present exemplary embodiment, the terminal 130 receives service type information for the neighboring cell and service type information for the neighboring cell from at least one neighboring cell located adjacent to the location of the terminal 130 Related information including information, and performs a cell reselection procedure to a specific neighboring cell in which the actual terminal 130 can provide the service to be performed.

In this way, according to the cell reselection method of the terminal 130 according to the present embodiment, it is possible to prevent the selection of a cell that does not meet the requirements requested from the terminal 130, Time delay and load generation can be improved, and as a result, network resources can be efficiently used.

The foregoing description is merely illustrative of the technical idea of the present embodiment, and various modifications and changes may be made to those skilled in the art without departing from the essential characteristics of the embodiments. Therefore, the present embodiments are to be construed as illustrative rather than restrictive, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The scope of protection of the present embodiment should be construed according to the following claims, and all technical ideas within the scope of equivalents thereof should be construed as being included in the scope of the present invention.

100, 110, 120: cells 102, 112, 122:
130: terminal 200:
210: cell management unit 220: cell selection unit
230: connection control section 240: handover control section
400: serving base station 410: target base station

Claims (11)

A terminal of a mobile communication system,
A communication unit for receiving cell related information including service type information for the neighboring cell from a base station of at least one adjacent cell adjacent to the terminal;
A cell management unit for generating a cell-based support service list defining a supportable service for each of the neighboring cells based on the cell-related information; And
A cell selection unit for determining a cell of a connection priority order among the neighboring cells based on the cell-
And a second terminal. The method according to claim 1,
Wherein the cell selector comprises:
The method comprising: confirming service type information on a service to be performed in the terminal, and identifying, based on the confirmed service type information and the support service list for each cell, Cell as a cell. 3. The method of claim 2,
Wherein the cell selector comprises:
Wherein when a plurality of specific peripheral cells are calculated, the terminal determines any one of the plurality of specific peripheral cells as the cell of the connection priority order by further utilizing predetermined priority information. The method according to claim 1,
Further comprising a connection controller for performing a cell selection or a cell reselection procedure on the access priority cell according to a current state of the terminal. The method according to claim 1,
The cell-
Further comprising service type information for neighboring cells adjacent to the terminal. 6. The method of claim 5,
Further comprising a handover controller for performing a handover procedure for the MS using the service type information for the neighboring cells. The method according to claim 6,
The handover control unit includes:
Selecting a cell among the neighboring cells that can support the service of the terminal as a target cell as a handover candidate cell based on service type information for the other neighboring cells, (Hereinafter, referred to as 'Serving Cell') in which a connection report is transmitted to a terminal connected to the terminal. 8. The method of claim 7,
The handover control unit includes:
When a handover request message is received from the serving cell, the handover request message is handed over to the target cell, and when the handover request message is confirmed to support the service of the terminal for the target cell And selectively transmitted from the serving cell. A method for selecting a cell in a mobile communication system,
Receiving cell-related information including service type information for the neighboring cell from a base station of at least one adjacent cell adjacent to the terminal;
Generating a list of support services for each cell defining a supportable service for each of the neighboring cells based on the cell-related information; And
Determining a cell of a connection priority order among the neighboring cells based on the cell-by-cell support service list
And transmitting the selected cell to the terminal. 10. The method of claim 9,
Wherein the determining comprises:
The method comprising: confirming service type information on a service to be performed in the terminal, and identifying, based on the confirmed service type information and the support service list for each cell, Cell as a cell. 10. The method of claim 9,
Wherein the receiving further receives service type information for neighboring cells adjacent to the terminal as cell related information,
Further comprising the step of performing a handover procedure for the MS using the service type information for the neighboring cells.

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