KR101554553B1 - Apparatus and method for controling frequency band which mobile terminal connects at multi carrier circumstance - Google Patents

Abstract

The terminal connection adjustment apparatus according to the present invention comprises a QCI policy checking unit for checking a QCI policy specifying a frequency band to which a terminal accesses according to a QoS class identifier (QCI) value, And a connection control unit for controlling the terminal to access through the frequency band corresponding to the confirmed QCI value based on the QCI policy, the QCI identifying unit identifying the QCI value corresponding to the service category, .

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and a method for adjusting a frequency band in which a terminal accesses a base station in a multicarrier environment,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and method for adjusting a frequency band to which a terminal connects to a base station and more particularly to an apparatus and method for adjusting a frequency band of a terminal capable of connecting to a base station in a plurality of frequency bands through a multi- To an apparatus and a method for adjusting by referring to a QCI value.

The LTE (Long Term Evolution) system is a mobile communication system evolved in the UMTS system and has been established as a standard in the 3rd Generation Partnership Project (3GPP), an international standardization organization.

In recent LTE systems, a multicarrier service is provided utilizing a frequency band (for example, 1.8 GHz band) other than the frequency band (for example, 800 MHz band) used in the past. ) Scheme is a method of transmitting a radio signal to a terminal using a carrier of a plurality of frequency bands.

A mobile communication base station for supporting a multicarrier service places a remote radio unit (RRU) for outputting radio signals of respective frequency bands adjacent to each other, The terminals in the corresponding area can be connected to any one of the frequency bands. A terminal supporting reception of a multicarrier can receive downlink data by connecting to any one of a plurality of frequency bands, thereby improving the download transmission rate.

In the LTE-A (LTE Advanced) system using LTE system, carrier aggregation (CA) using multi-carrier is adopted. Carrier aggregation technology is a technique in which a component carrier of several frequency bands, CC) are integrated into one, so that data can be transmitted over a wider frequency band.

More specifically, the terminal connects to the base station through a predetermined frequency band in an idle state, and then senses and adds a radio signal of a different frequency band, thereby generating a radio signal of a plurality of frequency bands Can be received at the same time. Here, a cell in a frequency band in which a terminal initially connects in a dormant state is referred to as a Pcell (Primary cell), and a cell in a frequency band that can be connected after being connected to a Pcell is referred to as a Scell (Secondary cell) It is possible to simultaneously connect to the above scell and improve the download transmission speed by the number of the theoretically connected cells.

On the other hand, according to the mobile communication policy, a frequency band including a wider bandwidth may be allocated to a specific mobile communication service provider. For example, a plurality of frequency bands having different bandwidths may be allocated, such as a 10 MHz bandwidth in the 800 MHz band and a 20 MHz bandwidth in the 1.8 GHz band. In this case, when the terminal is connected to the 800 MHz band having a bandwidth of 10 MHz, when the maximum throughput of the downlink is 75 Mbps and the 1.8 GHz band having the bandwidth of 20 MHz is connected, the maximum transmission rate can be realized as 150 Mbps, It would be preferable for the entire system to adjust the terminal to receive a packet of a service requiring a transmission rate to connect to a 1.8 GHz band capable of a broadband service.

In addition, since a high quality of service (QoS) is required for a packet requiring real-time processing such as a voice call through Voice over LTE (VoLTE) or signaling between a terminal and a base station, It is preferable from the viewpoint of QoS guarantee.

However, in the current multicarrier system, the terminal occupies a specific frequency band according to the system parameter set in the terminal in the idle state, and then when the RRC connection is attempted for communication with the base station, the terminal accesses through the occupied frequency band You will be asked.

Therefore, even if a multicarrier service is provided in a plurality of frequency bands having different bandwidths on the conventional system, it is not possible to select the frequency band to which the terminal is connected according to the type of service. Thus, inefficiency to be.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problem by providing a method and apparatus for adjusting a frequency band to be connected to a terminal according to a QCI (Quality of Service Identifier) value in a multicarrier environment using a plurality of frequency bands having mutually non- And to provide a terminal connection coordinating apparatus and a terminal connection coordination method which can ensure a proper QoS for each service at the same time.

According to the present invention, there is provided an apparatus for adjusting a frequency band in which a terminal accesses a base station in a multicarrier environment, the apparatus comprising: a QCI policy specifying a frequency band to which a terminal accesses, according to a QCI (QoS Class Identifier) A QCI policy verifying unit for verifying; A QCI checking unit for identifying a service category through a packet transmitted from a terminal and confirming a QCI value corresponding to the service category; And a connection control unit which controls, based on the QCI policy, that the terminal connects through a frequency band corresponding to the identified QCI value.

Here, the QCI policy checking unit may store table information mapping the service category, the QCI value, and the access frequency band, and may determine a frequency band to which the terminal accesses by referring to the table information.

Herein, the terminal may be connected through any one of a plurality of frequency bands having different bandwidths, and the QCI policy may be configured such that, for a QCI value corresponding to a service category requiring a high transmission rate among the service categories, And may be set to connect to a frequency band having a wide bandwidth out of the frequency bands.

Here, the connection control unit may transmit a frequency transition message to the terminal, when the terminal is connected through a frequency band different from the frequency band corresponding to the checked QCI value, Lt; / RTI >

Here, the terminal receiving the access refusal message and the frequency transition message may request access through the frequency band corresponding to the QCI value.

According to another aspect of the present invention, there is provided a method for adjusting a frequency band in which a terminal accesses a base station in a multi-carrier environment, the method comprising: receiving a packet transmitted from a terminal; Identifying a service category through the transmitted packet and confirming a QCI value corresponding to the service category; Determining whether the terminal is connected through a frequency band corresponding to the identified QCI value based on a preset QCI policy; And transmitting to the terminal a frequency shift message that causes the terminal to transition to another frequency band together with a connection rejection message when the terminal is accessing through a frequency band different from the frequency band corresponding to the identified QCI value Terminal connection adjustment method.

Here, the terminal may further include a step of requesting connection through a frequency band corresponding to the QCI value after receiving the frequency shift message.

Herein, the terminal may be connected through any one of a plurality of frequency bands having different bandwidths, and the QCI policy may be configured such that, for a QCI value corresponding to a service category requiring a high transmission rate among the service categories, And may be set to connect to a frequency band having a wide bandwidth out of the frequency bands.

According to the present invention, in a multi-carrier environment using a plurality of frequency bands having mutually asymmetric bandwidths, a frequency band to which a terminal accesses is adjusted according to a QCI (QoS Class Identifier) value, It is possible to provide a terminal connection coordinating apparatus and a terminal connection coordination method which can ensure an appropriate QoS for each service.

1 schematically illustrates a mobile communication system supporting a multi-carrier according to an embodiment of the present invention.
2 is a block diagram of a terminal connection adjustment apparatus according to an embodiment of the present invention.
3 is a flowchart of a terminal connection adjustment method according to an embodiment of the present invention.

It is noted that the technical terms used herein are used only to describe specific embodiments and are not intended to limit the invention. It is also to be understood that the technical terms used herein are to be interpreted in a sense generally understood by a person skilled in the art to which the present invention belongs, Should not be construed to mean, or be interpreted in an excessively reduced sense. Further, when a technical term used herein is an erroneous technical term that does not accurately express the spirit of the present invention, it should be understood that technical terms that can be understood by a person skilled in the art are replaced. In addition, the general terms used in the present invention should be interpreted according to a predefined or prior context, and should not be construed as being excessively reduced.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like or similar elements throughout, and redundant description thereof will be omitted. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. It is to be noted that the accompanying drawings are only for the purpose of facilitating understanding of the present invention, and should not be construed as limiting the scope of the present invention with reference to the accompanying drawings. The spirit of the present invention should be construed as extending to all modifications, equivalents, and alternatives in addition to the appended drawings.

1 schematically illustrates a mobile communication system supporting a multi-carrier according to an embodiment of the present invention.

The mobile communication system according to the present invention may include an LTE (Long Term Evolution) system, and may use a multi-carrier (MC) technology. The multi-carrier technique is a method of transmitting a radio signal to a terminal using a carrier wave of a plurality of frequency bands, and a carrier wave of a frequency band in which a terminal can receive downlink data at a higher transmission rate And connect them. For example, on the base station 10 side, each RRU (Radio Resource Unit) capable of transmitting a carrier in a first frequency band (for example, 1.8 GHz band) and a second frequency band (for example, 800 MHz band) Is provided at an adjacent position and the terminal also has a wireless communication module capable of receiving wireless signals of the first frequency band and the second frequency band so that the terminal can perform wireless communication through any one of the two bands.

In this specification, the frequency band of the radio signal transmitted by the base station 10 is described as two frequency bands 12 and 14 as shown in Fig. 1. This is for the purpose of explaining the feature of the present invention, In a case where a multi-carrier service is implemented by transmitting a radio signal in the above frequency band, there is no problem in realizing the technical characteristic of the present invention. Hereinafter, for convenience of explanation, it is assumed that the 1.8 GHz band is referred to as a first frequency band and the 800 MHz band is referred to as a second frequency band, and it is assumed that a broadband service can be provided in the 1.8 GHz band as compared with the 800 MHz band I will explain.

1, a cell 12 of a first frequency band and a cell 14 of a second frequency band are both formed around a base station 10, Or the like.

In this case, the terminal occupies a predetermined frequency band in an idle state. For example, from a predetermined one of the first frequency band 12 and the second frequency band 14, Block) message and a paging message. At this time, the frequency band occupied by the terminal in the idle state can be determined according to a system parameter defined on the terminal.

Thereafter, when the terminal awakes from the idle state and desires to establish a communication connection with the base station 10, a procedure for making an RRC connection with the base station 10 is required. The Radio Resource Control (RRC) layer is defined in the control plane and includes radio resources between the UE and the access network, such as control of transport channels and physical channels associated with setting, resetting, and releasing of radio bearers (RBs) And transmits and controls parameters necessary for use. At this time, the setting of the RRC between the MS and the BS 10 can be performed under the control of a Mobile Mobility Entity (MME).

In order to establish an RRC connection with the base station 10, the terminal transmits an RRC request message through a frequency band occupied in a dormant state to request a call connection. Thereafter, the base station 10 transmits an RRC setup message (RRC setup message) to the UE, and transmits a RRC setup complete message to the base station 10 from the base station 10, thereby completing the RRC connection, The data communication between the terminal 10 and the terminal becomes possible. Thereafter, when a frequency shift message is received as described later, it is possible to perform handoff to another frequency band.

The mobile communication system according to the present invention may be configured as an LTE-Advanced (LTE-Advanced) system using Carrier Aggregation (CA). In the carrier aggregation technology, a carrier wave that can be used in an LTE system is defined as a component carrier (CC), and the system is configured so that the data carrier rate can be increased theoretically by the number of element carriers by bundling each carrier wave , The feature of adjusting the connection frequency band of the terminal in the present invention may be directly applicable to adjusting the frequency band of the Pcell on the LTE-A system.

A terminal on the LTE-A system connects RRC to any one of a plurality of frequency bands and detects and adds another frequency band thereafter, thereby receiving a downlink signal from the base station 10 in a plurality of frequency bands Lt; / RTI > At this time, a cell in a frequency band in which a terminal first connects in a dormant state is referred to as a Pcell (Primary cell), and a cell in a frequency band to which the terminal is connected is referred to as a Scell (secondary cell).

For example, if the terminal occupies the first frequency band in the idle state, it sets the cell 12 of the first frequency band to Pcell and requests the base station 10 to make an RRC connection, It is possible to request the base station 10 to establish a connection by setting the cell 14 of the second frequency band to Scell.

Meanwhile, the terminal can receive various communication services after connection with the base station. When the category of the service is largely classified, the terminal can perform data communication such as voice call (VoLTE), streaming service, And so on. In case of voice call, real-time transmission is required, so it is necessary to guarantee high QoS. In case of data communication, even if a lower QoS is provided, it will be acceptable for users.

As described above, a QoS class identifier (QCI) is defined in order to define a QoS-related value to be provided according to the category of the communication service to be performed. QCI is a QoS (Quality of Service) priority represented by integer values 1 to 9. Each value indicates a resource type (GBR or non-GBR), a priority, a packet delay budget, a packet loss tolerance Error Loss Rate). QCI is defined in Table 6.1.7 of 3GPP TS23.203 and its content is shown in Table 1 below.

[Table 1]

In an actual mobile communication system, QoS can be provided by selecting only a part of QCIs 1 through 9, which do not match QCIs 1 through 9, for every service category. For example, the QCI value may be set to 1 for a voice call service via VoLTE, the QCI value may be set to 2 for a video call service, and the QCI value may be set to 6 for the remaining data communication services.

Hereinafter, a feature of the present invention in which a terminal applies a predefined QCI value according to a category of a service provided when communicating with a base station and adjusts a frequency band accessed by the terminal according to the QCI value will be described in detail do.

2 is a block diagram of a terminal connection coordinating apparatus 100 according to an embodiment of the present invention.

As shown in the figure, the terminal connection coordinating apparatus 100 includes a QCI policy checking unit 110, a QCI checking unit 120, and a connection control unit 130. The terminal access coordinator 100 may be implemented by a channel card that is responsible for connection of the terminal 200 in the cell and scheduling of radio resource allocation on a Digital Unit (DU) of the base station, and is not limited in specific implementation.

The QCI policy checking unit 110 checks the QCI policy specifying the frequency band to which the terminal 200 accesses according to the QCI value. The QCI policy may include table information mapping the service category, the QCI value, and the access frequency band, as described above with reference to Table 1, and mapping corresponding QCI values for each service category using only a part of the QCI values .

Assuming that the first frequency band has a bandwidth larger than that of the second frequency band and can realize a relatively high transmission rate on the mobile communication system as an example of the QCI policy, in the case of data communication requiring a high transmission rate And can be connected through the first frequency band. In addition, since a resource block that can be allocated by a base station through a specific frequency band is limited, in the case of a voice call requiring a high QoS, a frequency band different from a data communication for generating a large number of packets It may be preferable to connect through the band.

Thus, the QCI policy can be set to connect to a frequency band having a wide bandwidth among the plurality of frequency bands, with respect to a QCI value corresponding to a service category requiring a high transmission rate in the service category. For example, the QCI policy may set the QCI value to 1 when the terminal 200 communicates with the base station for the voice call service, and may set the QCI value to 6 when the data communication service is used, and the QCI value may be set to 6 , The connection frequency band may be set to a first frequency band (e.g., 1.8 GHz band) and the connection frequency band may be set to a second frequency band (e.g., 800 MHz band) when the QCI value is 1. [

This may be changed by setting the QCI policy and the terminal connection adjustment device as one embodiment for explaining the features of the present invention.

Such a QCI policy can be defined by PCRF (Policy and Charging Rule Function) on the core network. The QCI policy generated by the PCRF can be downloaded from the QCI policy checking unit 110 of the terminal access coordinator 100 and utilized have.

The QCI identifying unit 120 identifies the service category through the packet transmitted from the terminal 200 and confirms the QCI value corresponding to the service category.

More specifically, it is assumed that the terminal 200 occupies one of a plurality of frequency bands in the idle state, and hereinafter, occupies the first frequency band (for example, 1.8 GHz band).

When the terminal 200 intends to perform communication with the base station, the terminal 200 accesses the terminal through the first frequency band through the RRC connection procedure. At this time, the RRC connection is connected by forming a default bearer between the base station and the base station. Thereafter, when the terminal 200 requests a voice call service, the QCI identifying unit 120 identifies that the category of the service is a voice call through the packet transmitted from the terminal 200, Quot; 1 " is " 1 ".

In another embodiment, when the terminal 200 requests a voice call service, the QCI value 1 may be downloaded from a DPI (Deep Packet Inspection) or the like provided on the core network. The terminal 200 may utilize the QCI value 1 And the QCI checking unit 120 can check the QCI value transmitted from the terminal 200. The QCI checking unit 120 can check the QCI value transmitted from the terminal 200 in the first frequency band.

The connection control unit 130 controls the terminal 200 to access through the frequency band corresponding to the checked QCI value based on the QCI policy.

For example, when the terminal 200 requests a voice call service corresponding to the QCI value 1, it is defined to connect in the second frequency band when the QCI value is 1 in the QCI policy, . When the terminal 200 requests the data communication service corresponding to the QCI value 6, it is defined to connect in the first frequency band when the QCI value is 6 in the QCI policy, can do.

When the terminal 200 transmits a voice call service packet while accessing through the first frequency band, the QCI value of the voice call service is set to 1 in the QCI policy, and the access is set to the second frequency band in case of the QCI value 1 The connection control unit 130 transmits a frequency shift message to the terminal 200 in order to transition to another frequency band, that is, a second frequency band together with a connection rejection message.

Upon receiving the connection rejection message and the frequency transition message, the terminal 200 requests the connection through the frequency band corresponding to the QCI value, that is, the second frequency band, and the voice call service can be performed after the connection is completed.

Thereafter, when the terminal 200 terminates the voice call and transmits a packet relating to the data communication, the QCI identifying unit 120 identifies the category of the service as the data communication and confirms the corresponding QCI value 6 .

The connection control unit 130 refers to the QCI policy to confirm that the frequency band corresponding to the QCI value 6 is the first frequency band and transmits a connection rejection message and a frequency transition message .

Upon receiving the connection rejection message and the frequency transition message, the terminal 200 requests the connection again through the first frequency band, and the data communication service can be performed after the connection is completed.

According to the present invention, in a multi-carrier environment using a plurality of frequency bands, a service requiring a high transmission rate like data communication is performed by adjusting a frequency band to which a terminal accesses according to a QCI (QoS Class Identifier) value Terminals are connected through a frequency band including a wide band and a terminal performing a service requiring QoS guarantee such as voice communication is connected through another frequency band to obtain a high transmission rate for the system as a whole It is possible to guarantee QoS required for each service.

3 is a flowchart of a terminal connection adjustment method according to the present invention.

The terminal connection adjustment method according to the present invention can be performed by a terminal connection adjustment apparatus that can be provided on a base station, and the terminal 200 can be connected through any one of a plurality of frequency bands in a multicarrier environment.

It is assumed that the terminal 200 occupies one of a plurality of frequency bands in an idle state and occupies the first frequency band in operation S110. Here, the first frequency band refers to a 1.8 GHz band and the second frequency band refers to an 800 MHz band. The first frequency band has a wider bandwidth than the second frequency band, and can exhibit higher throughput. The terminal 200 may wait while receiving a System Information Block (SIB) message and a paging message periodically through the first frequency band in the idle state.

If the terminal 200 desires to perform data communication according to the user's request (S120), the terminal 200 requests connection through the occupied first frequency band (S130).

At this time, the terminal access coordinator 100 identifies the service category through the transmitted packet and confirms the QCI value corresponding to the service category. That is, it is confirmed that the service category is data communication, and the QCI value 6 is confirmed (S140).

The terminal connection coordinating apparatus 100 confirms that the connection frequency band is the first frequency band when the QCI value is 6 based on the QCI policy (S150).

At this time, when the terminal 200 requests the connection through the first frequency band, the terminal 200 accepts the connection and performs the data communication service (S160).

Thereafter, when the terminal 200 desires to perform a VoLTE-based voice call according to a user's request (S170), the terminal 200 requests connection via the first frequency band (S180).

At this time, the terminal access coordinator 100 identifies the service category as a voice call through the transmitted packet and confirms the QCI value 1 corresponding to the voice call service (S190).

In addition, the terminal connection adjustment device 100 confirms that the connection frequency band is the second frequency band when the QCI value is 1 based on the QCI policy (S200).

When the terminal 200 requests a connection via the first frequency band other than the second frequency band, the terminal connection coordinating apparatus 100 transmits a frequency transition message for transition to the second frequency band together with the connection rejection message (S210).

Upon receiving the connection rejection message and the frequency transition message, the terminal 200 requests connection via the second frequency band corresponding to the QCI value 1 (S220) based on the frequency transition message (S220) (S230).

According to the present invention, in a multi-carrier environment using a plurality of frequency bands, a service requiring a high transmission rate like data communication is performed by adjusting a frequency band to which a terminal accesses according to a QCI (QoS Class Identifier) value Terminals are connected through a frequency band including a wide band and a terminal performing a service requiring QoS guarantee such as voice communication is connected through another frequency band to obtain a high transmission rate for the system as a whole It is possible to guarantee QoS required for each service.

Meanwhile, the terminal connection adjustment method according to an embodiment of the present invention may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and configured for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

100: terminal connection adjusting device 110: QCI policy checking part
120: QCI verification unit 130: Connection control unit
200: terminal

Claims (8)

An apparatus for adjusting a frequency band in which a terminal connects to a base station in a multi-carrier environment,
A QCI policy confirmation unit for confirming a QCI policy specifying a frequency band to which a terminal accesses according to a QCI (Quality of Service) class identifier;
A QCI checking unit for identifying a service category through a packet transmitted from a terminal and confirming a QCI value corresponding to the service category; And
And a connection control unit for controlling the terminal to access through the frequency band corresponding to the checked QCI value based on the QCI policy.
The method according to claim 1,
The QCI policy checking unit,
Storing the service category, the QCI value, and table information mapping the connection frequency band,
And determines a frequency band to which the terminal accesses by referring to the table information.
3. The method of claim 2,
The terminals may be connected through any one of a plurality of frequency bands having different bandwidths,
Wherein the QCI policy is set to connect to a frequency band having a wide bandwidth among the plurality of frequency bands, with respect to a QCI value corresponding to a specific service category requiring a transmission rate higher than a preset value in the service category Adjusting device.
The method according to claim 1,
The connection control unit,
When the terminal is connected through a frequency band different from the frequency band corresponding to the confirmed QCI value, transmits a frequency transition message to the terminal, which causes a transition to another frequency band together with the connection rejection message Connection adjustment device.
5. The method of claim 4,
Upon receiving the access refusal message and the frequency transition message,
And requests a connection through a frequency band corresponding to the QCI value.
A method for adjusting a frequency band in which a terminal connects to a base station in a multi-carrier environment,
Receiving a packet transmitted from a terminal;
Identifying a service category through the transmitted packet and confirming a QCI value corresponding to the service category;
Determining whether the terminal is connected through a frequency band corresponding to the identified QCI value based on a preset QCI policy; And
And transmitting to the terminal a frequency transition message for transitioning to another frequency band together with the connection rejection message when the terminal is connected through a frequency band different from the frequency band corresponding to the identified QCI value Connection adjustment method.
The method according to claim 6,
Further comprising: after the terminal receives the frequency transition message, requesting a connection through a frequency band corresponding to the QCI value.
The method according to claim 6,
The terminals may be connected through any one of a plurality of frequency bands having different bandwidths,
Wherein the QCI policy is set to connect to a frequency band having a wide bandwidth among the plurality of frequency bands, with respect to a QCI value corresponding to a specific service category requiring a transmission rate higher than a preset value in the service category Adjustment method.

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