KR20100061333A - Method of determining an access mode of cell in a wireless communication system - Google Patents

Abstract

PURPOSE: A method of determining an access mode of cell in a wireless communication system is provided to connect to a terminal as a member when the terminal is the member of a CSG in a hybrid cell. CONSTITUTION: A terminal confirms a CSG(Closed Subscriber Group) indicator in the system information of a target cell in order to confirm the type of the target cell. When the CSG indicator indicates the target cell as the CSG cell, the terminal recognizes the target cell as the CSG cell. The terminal confirms the CSG identifier in the system information in order to confirm the CGS member of the target cell.

Description

METHOOD OF DETERMINING AN ACCESS MODE OF CELL IN A WIRELESS COMMUNICATION SYSTEM}

The present invention relates to a wireless communication system and a terminal for providing a wireless communication service. The present invention relates to a base station in an Evolved Universal Mobile Telecommunications System (E-UMTS) or a Long Term Evolution System (LTE), which is evolved from a Universal Mobile Telecommunications System (UMTS). The present invention relates to a method of determining an operation mode of a base station, that is, a cell access mode (or access mode), which is classified according to which UE is allowed to access. If it is determined that the access mode is not allowed, the present invention relates to a method of determining the access mode of a cell by checking the existence of a subscriber group identity.

1 is a diagram illustrating a network structure of an E-UTRAN (Evolved Universal Terrestrial Radio Access Network) which is a mobile communication system to which the present invention and the present invention are applied. The E-UTRAN system is an evolution from the existing UTRAN system and is currently undergoing basic standardization work in 3GPP. The E-UTRAN system is also called a Long Term Evolution (LTE) system.

The E-UTRAN is composed of eNBs (e-NodeBs, hereinafter referred to as base stations), and are connected between eNBs through an X2 interface. The eNB is connected to a user equipment (hereinafter abbreviated terminal) through a wireless interface and is connected to an Evolved Packet Core (EPC) through an S1 interface.

The EPC includes a mobility management entity (MME), a serving-gateway (S-GW), and a packet data network-gateway (PDN-GW). The MME has information about the access information of the terminal or the capability of the terminal, and this information is mainly used for mobility management of the terminal. S-GW is a gateway having an E-UTRAN as an endpoint, and PDN-GW is a gateway having a PDN as an endpoint.

Layers of the radio interface protocol between the terminal and the network are based on the lower three layers of the Open System Interconnection (OSI) reference model, which is widely known in communication systems. (Second layer) and L3 (third layer), wherein a physical layer belonging to the first layer provides an information transfer service using a physical channel, and a third layer. The radio resource control layer (hereinafter referred to as RRC) layer located in the layer plays a role of controlling radio resources between the terminal and the network. To this end, the RRC layer exchanges an RRC message between the terminal and the base station.

2 and 3 illustrate a structure of a radio interface protocol between a UE and an E-UTRAN based on the 3GPP radio access network standard. The wireless interface protocol consists of a physical layer, a data link layer, and a network layer horizontally, and vertically, a user plane for transmitting data information. -plane) and Control Plane (C-plane) for signal transmission. The protocol layers of FIGS. 2 and 3 are based on the lower three layers of the Open System Interconnection (OSI) reference model, which are well known in communication systems, and include L1 (first layer), L2 (second layer), L3 (third layer) can be divided. These radio protocol layers exist in pairs in the UE and the E-UTRAN, and are responsible for data transmission in the radio section.

Hereinafter, each layer of the wireless protocol control plane of FIG. 2 and the wireless protocol user plane of FIG. 3 will be described.

The physical layer, which is the first layer, provides an information transfer service to an upper layer by using a physical channel. The physical layer is connected to the upper medium access control layer through a transport channel, and data between the medium access control layer and the physical layer moves through the transport channel. Then, data is moved between different physical layers, that is, between physical layers of a transmitting side and a receiving side through physical channels. The physical channel is modulated by an orthogonal frequency division multiplexing (OFDM) scheme and utilizes time and frequency as radio resources.

Medium access control (hereinafter referred to as MAC) of the second layer provides a service to a radio link control layer, which is a higher layer, through a logical channel. The radio link control layer (hereinafter referred to as RLC) layer of the second layer supports reliable data transmission. The functionality of the RLC layer may be implemented as a functional block inside the MAC. In this case, the RLC layer may not exist. The PDCP layer of the second layer is a header compression that reduces the IP packet header size, which is relatively large and contains unnecessary control information, for efficient transmission in a low bandwidth wireless section when transmitting an IP packet such as IPv4 or IPv6. Compression) function.

The radio resource control layer (hereinafter abbreviated as RRC) layer located at the top of the third layer is defined only in the control plane, and the configuration and reset of the radio bearer (abbreviated as RB) are performed. It is responsible for the control of logical channels, transport channels and physical channels in relation to configuration and release. In this case, RB means a service provided by the second layer for data transmission between the terminal and the UTRAN. When there is an RRC connection (RRC Connection) between the RRC of the terminal and the RRC layer of the radio network, the terminal is in the RRC_CONNECTED state, otherwise it is in the RRC idle state (RRC_IDLE).

A downlink transmission channel for transmitting data from a network to a UE includes a broadcast channel (BCH) for transmitting system information and a downlink shared channel (SCH) for transmitting user traffic or control messages. Traffic or control messages of a downlink multicast or broadcast service may be transmitted through a downlink SCH or may be transmitted through a separate downlink multicast channel (MCH). Meanwhile, the uplink transmission channel for transmitting data from the terminal to the network includes a random access channel (RAC) for transmitting an initial control message and an uplink shared channel (SCH) for transmitting user traffic or control messages.

It is located above the transport channel, and the logical channel mapped to the transport channel is a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and a multicast traffic (MTCH). Channel).

The physical channel is composed of several subframes on the time axis and several subcarriers on the frequency axis. Here, one sub-frame consists of a plurality of symbols on the time axis. One subframe consists of a plurality of resource blocks, and one resource block consists of a plurality of symbols and a plurality of sub-carriers. In addition, each subframe may use specific subcarriers of specific symbols (eg, the first symbol) of the corresponding subframe for a physical downlink control channel (PDCCH), that is, an L1 / L2 control channel. One subframe is 0.5 ms, and a transmission time interval (TTI), which is a unit time for transmitting data, is 1 ms corresponding to two subframes.

Hereinafter, the RRC state and the RRC connection method of the UE will be described in detail. The RRC state refers to whether or not the RRC of the UE is in a logical connection with the RRC of the E-UTRAN. If connected, the RRC connected state (RRC_CONNECTED state), and if not connected, the RRC idle state (RRC_IDLE). state). Since the UE of the RRC_CONNECTED state has an RRC connection, the E-UTRAN can grasp the existence of the UE in units of cells, and thus can effectively control the UE. On the other hand, the UE of the RRC_IDLE state cannot be understood by the E-UTRAN, and the core network manages the tracking area unit, which is a larger area unit than the cell. That is, the RRC_IDLE state terminal is identified only in a large area unit, and must move to the RRC_CONNECTED state in order to receive a normal mobile communication service such as voice or data.

When the user first powers on the terminal, the terminal first searches for an appropriate cell and then stays in the RRC Idle state in the cell. When the UE staying in the RRC_IDLE state needs to establish an RRC connection, the UE establishes an RRC connection with the RRC of the E-UTRAN through an RRC connection procedure and transitions to the RRC_CONNECTED state. There are several cases in which the UE in the idle state needs to establish an RRC connection. For example, an uplink data transmission is necessary due to a user's call attempt, or a paging message is received from the E-UTRAN. In one case, the response message may be transmitted.

The NAS (Non-Access Stratum) layer located above the RRC layer performs functions such as session management and mobility management.

In order to manage mobility of the UE in the NAS layer, two states of EMM-REGISTERED (EPS Mobility Management-REGISTERED) and EMM-DEREGISTERED are defined, and these two states are applied to the UE and the MME. The initial terminal is in the EMM-DEREGISTERED state, and the terminal performs a process of registering with the network through an initial attach procedure to access the network. If the attach procedure is successfully performed, the UE and the MME are in an EMM REGISTERED state.

In order to manage a signaling connection between the UE and the EPC, two states are defined, ECM-IDLE (EPS Connection Management) and ECM_CONNECTED, and these two states are applied to the UE and the MME. When the UE in the ECM-IDLE state establishes the RRC connection with the E-UTRAN, the UE enters the ECM-CONNECTED state. The MME in the ECM-IDLE state becomes the ECM-CONNECTED state when it establishes an S1 connection with the E-UTRAN. When the terminal is in the ECM-IDLE state, the E-UTRAN does not have context information of the terminal. Accordingly, the UE in the ECM-IDLE state performs a UE-based mobility related procedure such as cell selection or reselection without receiving a command from the network. On the other hand, when the terminal is in ECM-CONNECTED, the mobility of the terminal is managed by the command of the network. In the ECM-IDLE state, if the position of the terminal is different from the position known by the network, the terminal informs the network of the corresponding position of the terminal through a tracking area update procedure.

The following is a description of system information. The system information includes essential information that the terminal needs to know in order to access the base station. Therefore, the terminal must receive all system information before accessing the base station, and must always have the latest system information. In addition, since the system information is information that all terminals in a cell should know, the base station periodically transmits the system information.

The system information is divided into MIB, SB, and SIB. The master information block (MIB) allows the terminal to know the physical configuration of the cell, for example, bandwidth. SB (Scheduling Block) informs the transmission information of the SIBs, for example, the transmission period. SIB (System Information Block) is a collection of system information related to each other. For example, some SIBs contain only information of neighboring cells, and some SIBs contain only information of uplink radio channels used by the terminal.

In the related art, an operation mode of a base station is divided into several access modes according to which terminal the base station allows to access. At this time, the base station configures a specific subscriber group (Closed Subscriber Group), it can provide a higher quality of service to the group subscribers. The base station operates in a connection mode (CSG cell) that allows only a terminal belonging to a specific subscriber group or access information (common cell) that does not have to belong to a specific group. A group indicator (CSG Indicator) was passed.

However, in addition to the two access modes (CSG cell, general cell), the base station may use a mixture of the two access modes. When the base station operates in such a hybrid access mode, the three access modes cannot be appropriately distinguished by a method of distinguishing the access modes using only the CSG indicator. In this case, although the terminal is a CSG member, there is a problem that the CSG service is not provided from the base station.

Accordingly, the present invention seeks to determine the access mode of a cell in a wireless communication system more effectively than in the prior art.

In order to solve the above problems of the present invention, a method of determining an access mode of a cell in a wireless communication system, the method of determining whether the access mode of the cell is the first mode, In the first mode, only one or more terminals are allowed to access a specific subscriber group. If the access mode of the cell is determined to be an access mode other than the first mode, the subscriber group identity is determined. Confirming the presence; And considering the access mode of the cell as the second mode if the subscriber group identifier exists, in the second mode, one or more terminals or all terminals of the cell are selectively included in the specific subscriber group. Characterized in that the connection is allowed.

Preferably, the cell of the first mode is a CSG (Closed Subscriber Group) cell and the cell of the second mode is characterized in that the hybrid (Hybrid) cell.

Preferably, a cell type indicator is used to determine whether the connection mode of the cell is the first mode or not.

Preferably, the cell type indicator is a Closed Subscriber Group (CSG) indicator and the subscriber group identifier is characterized in that the CSG identifier.

Preferably, the hybrid cell is characterized in that the CSG indicator is set to 'FALSE' and broadcast the CSG identifier.

In addition, in order to solve the above problems of the present invention, a method of determining the access mode (cell) of the cell (access mode) in a wireless communication system, in the step of determining whether the terminal supports a specific access mode of the cell In the specific access mode, one or more terminals or all terminals of the cell are selectively allowed to access a specific subscriber group, and if it is determined that the terminal supports the specific access mode, a subscriber group identifier (subscriber group) identifying an identity; And if it is determined that the terminal does not support the specific access mode, checking a subscriber group indicator to determine the access mode of the cell.

Preferably, the cell in the specific connection mode is characterized in that the hybrid (Hybrid) cell.

Preferably, the accessor group identifier is characterized in that the CSG (Closed Subscriber Group) identifier.

Preferably, the accessor group indicator is characterized in that the CSG (Closed Subscriber Group) indicator.

In addition, to solve the problems of the present invention as described above, a method of determining the access mode (cell) of the cell (access mode) in a wireless communication system, to determine the access mode of the cell information and subscriber group identifier to the terminal In the providing step, the information indicates that the terminal is not a specific access mode, the specific access mode is characterized in that it includes allowing only one or more terminals to be connected in a specific subscriber group.

Preferably, the specific access mode cell is characterized in that the CSG (Closed Subscriber Group) cell.

Preferably, the information indicating that the terminal is not the specific access mode is characterized in that it is provided to the terminal by sending a subscriber group indicator (subscriber group indicator).

Preferably, the accessor group indicator is set to 'FALSE'.

Preferably, the information indicating that the terminal is not in the specific access mode is provided to the terminal by not sending a subscriber group indicator.

The present invention enables the terminal to identify the presence of the CSG identifier in addition to the CSG indicator in order to recognize the type of the cell so that the terminal can distinguish the hybrid cell from other types of cells. In addition, when the terminal confirms that the terminal is a hybrid cell, the terminal supporting the CSG additionally checks the CSG so that the CSG member can recognize the cell as the CSG cell. Through this, the present invention enables the terminal to access the CSG member when the terminal is a member of the CSG in the hybrid cell.

According to the present invention, when a UE recognizes a hybrid cell as a CSG cell to which it finally belongs, the UE may inform the network that it is a member of a target cell when attempting to access the cell or transmitting a handover request to the network. have. Then, the network including the target cell may regard the CSG member as having higher priority in the connection or handover process according to the operation policy. For example, when multiple UEs attempt to access or hand over a hybrid cell and contention occurs, the network may provide a higher quality service to the CSG member by providing a priority to the CSG member.

The present invention is applied to 3GPP communication technology, in particular, a Universal Mobile Telecommunications System (UMTS) system or a Long Term Evolution (LTE) system, a communication device, and a communication method. However, the present invention is not limited thereto and may be applied to all wired and wireless communication to which the technical spirit of the present invention can be applied.

The basic concept of the present invention is a method of determining an access mode of a cell in a wireless communication system, and in determining whether the access mode of the cell is a first mode, in the first mode, Only one or more terminals in the subscriber group are allowed access, and if it is determined that the access mode of the cell is a connection mode other than the first mode, confirming the existence of a subscriber group identity. Wow; And considering the access mode of the cell as the second mode if the subscriber group identifier exists, in the second mode, one or more terminals or all terminals of the cell are selectively included in the specific subscriber group. A method for determining a connection mode of a cell in a wireless communication system, characterized in that the connection is allowed, and a wireless mobile communication terminal capable of performing the method are proposed.

The present invention also provides a method of determining an access mode of a cell in a wireless communication system, the method for determining whether a terminal supports a specific access mode of the cell, wherein the specific access mode is specified. One or more terminals in the subscriber group or all terminals in the cell are selectively allowed to access, and if it is determined that the terminal supports the specific access mode, identifying a subscriber group identity; ; And if it is determined that the terminal does not support the specific access mode, checking a subscriber group indicator to determine the access mode of the cell. A method for determining a connection mode is proposed and a wireless mobile communication terminal capable of performing the method is proposed.

The present invention also provides a method of determining an access mode of a cell in a wireless communication system.

Providing information and a subscriber group identifier to a terminal to determine an access mode of the cell, wherein the information indicates that the terminal is not a specific access mode, and the specific access mode is one or more in a specific subscriber group. The present invention proposes a method for determining a connection mode of a cell in a wireless communication system comprising allowing only terminals to be connected and a network capable of performing such a method.

Hereinafter, the configuration and operation of the embodiments according to the present invention will be described with reference to the accompanying drawings.

In general, services provided by a network to a terminal can be classified into three types as follows. In addition, the terminal also recognizes the cell type differently according to which service can be provided. The following describes the service type first, followed by the cell type.

1) Limited service This service provides Emergency Call and Tsunami Warning System (ETWS), which can be provided by an acceptable cell.

2) Normal service This service means a general use for general use, and can be provided in a suitable or normal cell.

3) Operator service This service means service for network operator. This cell can be used only by network operator and not by general users.

In relation to the service type provided by the cell, the cell types may be classified as follows.

1) Acceptable cell A cell in which the terminal can receive limited service. This cell is a cell that is not barred from the viewpoint of the terminal and satisfies the cell selection criteria of the terminal.

2) Suitable cell A cell where the terminal can receive normal service. This cell satisfies the conditions of an acceptable cell and at the same time satisfies additional conditions. As an additional condition, this cell must belong to a PLMN to which the terminal can access and must be a cell which is not prohibited from performing a tracking area update procedure of the terminal. If the cell is a CSG cell, the terminal should be a cell that can be connected to the cell as a CSG member.

3) Barred cell A cell that broadcasts information indicating that the cell is a barred cell through system information.

4) Reserved cell A cell that broadcasts information indicating that a cell is a reserved cell through system information.

4 is an exemplary diagram illustrating a procedure for UE operation of selecting a cell in an idle mode.

In the first step, the terminal selects a radio access technology (hereinafter, abbreviated as RAT) for communicating with a network (public land mobile network; hereinafter abbreviated as PLMN) that it wants to receive. The PLMN and RAT information may be selected by the user of the terminal, or may be stored in the USIM.

In a second step, the terminal selects a cell having the largest value among the measured base station and a cell whose signal strength or quality is greater than a specific value (Cell Selection). Then, the base station periodically receives the SI. The above specific value refers to a value defined in the system in order to ensure the quality of the physical signal in data transmission / reception. Therefore, the value may vary depending on the RAT applied.

In a third step, the terminal registers its information (eg IMSI) to receive a service (eg paging) from the network. In this case, the terminal does not register with the accessing network every time the cell is selected, and information of the network (eg, Tracking Area Identity (TAI)) received from the SI and information of the network known to the UE are not registered. In other cases, register on the network.

In a fourth step, the terminal may have better signal characteristics than the cell of the base station to which the terminal is connected if the strength or quality of the signal measured from the base station being service is lower than the value measured from the base station of the adjacent cell. Select one of the other cells providing. This process is called cell re-selection, which is distinguished from initial cell selection of the second step. In this case, in order to prevent the cell from being frequently reselected according to the change of the signal characteristic, a time constraint may be provided.

Next, a procedure of selecting a cell by the terminal will be described in detail. When the terminal is powered on, the terminal should perform a preparation procedure for receiving a service by selecting a cell of a suitable quality.

A UE in an RRC idle (RRC_IDLE) state should always be prepared to select a cell of appropriate quality and to receive service through this cell. For example, a terminal that has just been powered on must select a cell of appropriate quality to register with the network. When the UE in the RRC_CONNECTED state enters RRC_IDLE, the UE should select a cell to stay in RRC_IDLE. As such, the process of selecting a cell that satisfies a certain condition in order for the terminal to stay in a service standby state such as an RRC_IDLE state is called cell selection. Importantly, since the cell selection is performed in a state in which the UE does not currently determine a cell to stay in the RRC_IDLE state, it is most important to select a cell as soon as possible. Therefore, if the cell provides a radio signal quality of a predetermined criterion or more, even if this cell is not the cell providing the best radio signal quality to the terminal, it may be selected during the cell selection process of the terminal.

Hereinafter, a method and procedure for selecting a cell by an LTE terminal will be described in detail. When the terminal is initially powered on, the terminal searches for an available PLMN and selects an appropriate PLMN for receiving a service. Subsequently, the UE selects a cell having a signal quality and characteristics capable of receiving an appropriate service from among cells provided by the selected PLMN. Here, the cell selection process is largely divided into two types. First, an initial cell selection process, in which the terminal does not have prior information on the radio channel. Accordingly, the terminal searches all radio channels to find an appropriate cell. The terminal finds the strongest cell in each channel. Thereafter, the terminal selects a corresponding cell if it finds a suitable cell that satisfies the cell selection criteria. The following is a cell selection process using stored information. In this process, cell selection is performed by using information stored in the terminal for a radio channel or by using information broadcast in a cell. Therefore, the cell selection may be faster than the initial cell selection process. If the terminal only finds a cell that satisfies a cell selection criterion, the terminal selects the cell. If a suitable cell that satisfies the cell selection criteria is not found through this process, the UE performs an initial cell selection process.

The cell selection criteria used by the terminal in the cell selection process may be as shown in the formula in Table 1 below.

The factors used in the above cell selection criteria are as follows.

Q _rxlevmeas reception level (RSRP) of the measured cell.

-Q _rxlevmin Minimum Required Receive Level in Cell (dBm)

Q _{rxlevminoffset} offset for Q _rxlevmin

-Pcompensation max (P _EMAX -P _UMAX , 0) (dB)

-Maximum transmit power (dBm) that PEMAX terminal can transmit in corresponding cell

-Maximum transmit power (dBm) of the terminal radio transmitter (RF) according to the performance of the PUMAX terminal

In Table 1, the UE can know that the measured strength and quality of the signal selects a cell larger than a specific value determined by the cell providing the service. In addition, the parameters used in Table 1 are broadcast through system information, and the terminal receives these parameter values and uses them in cell selection criteria.

When the terminal selects a cell that satisfies a cell selection criterion, the terminal receives information necessary for the RRC_IDLE mode operation of the terminal in the cell from the system information of the cell. After the UE receives all the information necessary for the RRC_IDLE mode operation, the UE waits in the idle mode to request a service (eg, an originating call) or to receive a service (eg, a terminating call) from the network.

After the terminal selects a cell through a cell selection process, the strength or quality of a signal between the terminal and the base station may change due to a change in mobility or a wireless environment of the terminal. Therefore, if the quality of the selected cell is degraded, the terminal may select another cell that provides better quality. When reselecting a cell in this way, a cell that generally provides better signal quality than the currently selected cell is selected. This process is called cell reselection. The cell reselection process has a basic purpose in selecting a cell that generally provides the best quality to a terminal in view of the quality of a radio signal. In addition to the quality of the wireless signal, the network may determine the priority for each frequency and notify the terminal. Upon receiving this priority, the UE considers this priority prior to the radio signal quality criteria in the cell reselection process.

As described above, there is a method of selecting or reselecting a cell according to a signal characteristic of a wireless environment, and in selecting a cell for reselection when the cell is reselected, the radio access technology of the cell (hereinafter abbreviated as RAT). There may be the following cell reselection method according to the and frequency characteristics.

Intra-frequency cell reselection Reselects a cell having the same center-frequency as the radio technology (RAT) same as the cell being used by the UE.

Inter-frequency cell reselection Reselects a cell having a center-frequency different from a radio technology (RAT) such as a cell being used by the UE

Inter-RAT cell reselection Reselects a cell using a radio technology (RAT) different from the radio technology being used by the terminal

Meanwhile, 3G or EPS (Evolved Packet System) service may be provided through a base station owned by an individual or a specific operator or a group other than a mobile communication network operator. Such a base station is called a Home Node B (HNB) or a (Home eNB; HeNB). Hereinafter, both the HNB and the HeNB are collectively referred to as H (e) NB. The H (e) NB basically aims to provide a specialized service only to a specific user group (Closed Subscriber Group, CSG). However, the service may be provided to other users in addition to the CSG according to the operation mode setting of the H (e) NB.

5 is an exemplary diagram illustrating a network structure of an E-UTRAN operating an H (e) NB using an H (e) NB gateway (GW).

As shown in FIG. 5, the HeNBs are connected to the EPC or directly to the EPC via the HeNB GW. Here, the HeNB GW looks like a normal eNB to the MME. The HeNB GW also looks like the MME to the HeNB. Therefore, the HeNB GW and the EPC are connected through the S1 interface between the HeNB and the HeNB GW. In addition, when the HeNB and the EPC are directly connected, they are connected to the S1 interface. The function of HeNB is mostly the same as that of general eNB.

In general, the H (e) NB has a lower radio transmission power than the (e) NB owned by the mobile network operator. Therefore, the coverage provided by the H (e) NB is generally smaller than the coverage provided by the (e) NB. Due to this characteristic, a cell provided by an H (e) NB is often classified as a femto cell in comparison with a macro cell provided by (e) NB from a service area perspective. On the other hand, in terms of the service provided, when the H (e) NB provides a service only to the CSG group, the cell provided by the H (e) NB is called a CSG cell.

Each CSG has its own unique identification number, which is called a CSG identity (CSG identity). The terminal may have a list of CSGs belonging to the member, and the CSG list may be changed by a request of the terminal or a command of the network. In general, one H (e) NB may support one CSG.

H (e) The NB transmits the CSG ID of the CSG supported by itself to the member terminal of the corresponding CSG through the system information. When the UE finds a CSG cell, it can check which CSG the CSG cell supports by reading the CSG ID included in the system information. The terminal reading the CSG ID is regarded as a cell to which the cell can be accessed only when the UE is a member of the CSG cell.

H (e) NB does not always need to allow access to the CSG terminal. Depending on the configuration of the H (e) NB, it is also possible to allow connection of a terminal other than the CSG member. Which terminal is allowed to access is changed according to the configuration of H (e) NB, where the configuration setting means the setting of the operation mode of H (e) NB. The operation mode of the H (e) NB is divided into three types according to which UE provides a service.

1) Closed access mode A mode that provides services only to specific CSG members. H (e) NB provides the CSG cell.

2) Open access mode General (e) Mode that provides service without restriction of specific CSG member like NB. H (e) NB provides a general cell that is not a CSG cell.

3) Hybrid access mode It is possible to provide CSG service to specific CSG members and to provide services like non-CSG members to non-CSG members. CSG member UEs are recognized as CSG cells, and non-CSG member UEs are recognized as normal cells. These cells are called hybrid cells.

The H (e) NB informs the UE whether the cell it serves is a general cell, which is a CSG cell, so as to know whether the UE can access the cell. The H (e) NB operating in the closed access mode broadcasts that it is a CSG cell through system information. The H (e) NB operating in the open access mode broadcasts that it is not a CSG cell through the system information. As such, the H (e) NB includes a 1-bit CSG indicator in the system information indicating whether or not the cell it serves is a CSG cell. For example, the CSG cell broadcasts by setting the CSG indicator to TRUE. If the serving cell is not a CSG cell, the CSG indicator may be set to FALSE or a method of omitting CSG indicator transmission may be used. Since the UE should be able to distinguish the general cell provided by the (e) NB from the CSG cell, the general (e) NB also sends a CSG indicator (eg, FALSE) so that the UE knows that the cell type provided by the UE is the general cell. can do. In addition, the general (e) NB may not let the UE know that the cell type provided by the UE is a general cell by not transmitting the CSG indicator. Table 2 shows CSG related parameters transmitted by a corresponding cell for each cell type. Table 3 shows the types of terminals that allow connection by cell type.

6 is a first exemplary diagram illustrating a method of confirming an access mode of a base station by a terminal according to the present invention.

In a first step, the terminal first checks the CSG indicator in the system information of the target cell to determine what type of cell the target cell is. After confirming the CSG indicator, in a second step, if the CSG indicator indicates that the target cell is a CSG cell, the UE recognizes the cell as a CSG cell. Thereafter, the terminal checks the CSG identity (CSG identity or CSG identifier) in the system information to determine whether the UE is a CSG member of the target cell. When the terminal determines that the UE is a CSG member of the target cell from the CSG identifier, the terminal recognizes the cell as an accessible CSG cell.

If the terminal confirms that it is not a CSG member of the target cell from the CSG identifier, the terminal regards the cell as a cell that is not accessible. In the first step, if the CSG indicator indicates that the target cell is not a CSG cell, the terminal recognizes the target cell as a general cell. In addition, if the CSG indicator is not transmitted in the first step, the terminal recognizes the target cell as a general cell.

In general, a CSG cell and a macro cell may be operated simultaneously at a specific frequency. This frequency is called the mixed carrier frequency. The network may reserve specific physical layer cell identifiers for the CSG cell separately at the mixed carrier frequency. The physical layer cell identifier is called PCI (Physical Cell Identity) in the E-UTRAN system, and PSC (Physical Scrambling Code) in the UTRAN. For convenience of description, the physical layer identifier is expressed in PCI. At the mixed carrier frequency, the CSG cell informs the system information about the PCIs reserved for CSG at the current frequency. Upon receiving this information, the UE can determine whether a cell is a CSG cell or not a CSG cell from PCI of this cell when it discovers a cell at a corresponding frequency. The following describes how two terminals use this information.

First, in case of a UE that does not support CSG-related functions or does not have a CSG list as a member thereof, the UE does not need to consider the CSG cell as a selectable cell during cell selection / reselection. In this case, the terminal checks only the PCI of the cell, and if the PCI is a PCI reserved by the CSG, the cell can be immediately excluded from the cell selection / reselection process. In general, the PCI of a cell can be known immediately at the terminal when the physical layer confirms the existence of the cell.

Second, in case of a UE having a CSG list of which the UE is a member, when the UE wants to know a list of neighboring CSG cells at the mixed carrier frequency, the CSG identifier of the system information of all cells found in the entire PCI range. Instead of verifying, we only find a cell with a PCI reserved for CSG and we know that the cell is a CSG cell.

As described above, when the H (e) NB operates in either of the open access mode or the closed access mode, it is sufficient for the H (e) NB to broadcast a 1-bit CSG indicator to distinguish between the two modes. It was. In general (e) NB, the UE also distinguishes whether a corresponding cell is a CSG cell or a general cell through a CSG indicator transmitted by a base station.

However, the H (e) NB may be operated in a hybrid access mode in addition to the open access mode or the closed access mode. If the H (e) NB is operated in a hybrid access mode, the cell provided by the H (e) NB should be seen as a CSG cell to the member terminal and a general cell to a terminal which is not a member terminal. However, when the H (e) NB is operated in the hybrid access mode, it is a matter of what value the CSG indicator should be set. The UE looks at how the cell recognition changes according to the setting of the CSG indicator.

If this H (e) NB sets the CSG indicator as a CSG cell, the UE which does not support CSG or does not have an accessible CSG list recognizes this Hybrid cell as a CSG cell through this indicator and does not attempt to access it. Therefore, the UE which is not a member of the corresponding CSG is blocked in the hybrid cell. In this case, the cell is no longer a hybrid cell, and operates as if it is a CSG cell allowing access to only CSG member terminals.

Therefore, since the hybrid cell should be viewed as a general cell to a terminal that is not a CSG member and a terminal that does not support CSG, the CSG identifier of the hybrid cell is set to not the CSG cell. However, when the H (e) NB sets the CSG indicator to not the CSG cell, the UE recognizes the hybrid cell as a general cell and attempts to access the CSG indicator. At this time, since the UE does not consider whether it is a CSG member of the cell or not, the network cannot know whether the UE attempting to access is a CSG member of the cell or a UE that is not. Therefore, the H (e) NB cannot provide a better quality service to the CSG member terminal than the non-CSG member terminal in the access process. The access attempt may also include a handover process. For example, a situation in which a UE, which is a CSG member of a hybrid cell, informs a hybrid cell of a target cell of handover to a base station currently receiving a service for handover to the hybrid cell may be considered. At this time, if the UE indicates that the CSG indicator is not a CSG cell despite being a CSG member of the hybrid cell, the UE determines that the cell is a general cell and does not inform that it is a CSG member of the target cell. As such, even if a UE, which is a CSG member of a hybrid cell, performs a handover to this hybrid cell, the network does not know that the UE is a CSG member of the corresponding hybrid cell, and thus differentiates the terminal from other non-member terminals in the handover process. Cannot provide services. That is, in the conventional method of determining the cell type using only the CSG indicator, the CSG service may not be provided to a specific CSG member and a hybrid access mode-specific service may be provided to a non-CSG member as a normal cell.

Accordingly, the present invention provides a method for a UE to check whether the H (e) NB is currently operated in the open / closed / hybrid access mode through the CSG indicator and the CSG identifier. In addition, in the present invention, if the UE confirms that the H (e) NB is operated in the hybrid access mode during the H (e) NB access process using the above method, whether the corresponding hybrid cell should be regarded as a CSG cell or should be regarded as a general cell. It provides a way to check.

In the present invention, the H (e) NB operating in the hybrid access mode sets the CSG indicator of the hybrid cell to the non-CSG cell and transmits the hybrid cell to the UE which does not support the CSG. Make it visible as a cell. However, since the hybrid cell can provide CSG service to the CSG member terminal, the hybrid cell transmits the CSG ID. Therefore, CSG-related parameter values for each cell type are shown in Table 4 below.

Table 5 shows a terminal type that allows connection by cell type and a connection type that allows.

7 is a second exemplary diagram illustrating a method of confirming an access mode of a base station by a terminal according to the present invention. In FIG. 7, the UE additionally recognizes the hybrid cell and, if the hybrid cell is present, confirms whether or not it is a CSG member of the corresponding cell, and expresses a procedure of concretely determining the cell type. This is described in detail below.

In a first step, the terminal first checks the CSG indicator in the system information of the target cell to determine what type of cell the target cell is. After confirming the CSG indicator, in a second step, if the CSG indicator indicates that the target cell is a CSG cell, the UE recognizes the cell as a CSG cell. Thereafter, the terminal checks the CSG identifier in the system information to confirm that the UE is a CSG member of the target cell. If the terminal confirms that the terminal is a CSG member of the target cell from the CSG identifier, the terminal recognizes the corresponding cell as an accessible CSG cell, and if the terminal identifies that the terminal is not a CSG member of the target cell from the CSG identifier. If so, the cell is regarded as a cell that is not accessible.

If in the first step, the CSG indicator indicates that the target cell is not a CSG cell, the terminal checks whether the target cell is transmitting a CSG identity (CSG identity). Subsequently, if it is determined that the CSG identifier is being transmitted, the terminal recognizes the target cell as a hybrid cell, checks the CSG identifier of the cell, and confirms that the terminal is a CSG member of the target cell. If it is confirmed that the CSG member, the terminal may recognize the cell as an accessible CSG cell and then notify the network. However, if it is confirmed that the UE is not a CSG member of the target cell, the UE may inform the network after recognizing the cell as a general cell. If the CSG identifier is not transmitted in the process of checking whether the CSG identifier exists, the terminal recognizes the target cell as a general cell.

8 is an exemplary diagram illustrating a base station access process of a CSG subscribed member terminal on a closed subscriber group (CSG) cell.

In a first step, the terminal receives system information including a CSG indicator and a CSG identifier from the base station. In this case, the system information may be received through various control channels such as a broadcast control channel (BCCH). After receiving the CSG indicator and the CSG identifier, the terminal first checks the received CSG indicator to determine whether the access target cell is a CSG cell, and after confirming that the access target cell is a CSG cell, the received CSG identifier After confirming that the terminal itself is a CSG member of the target cell, and starts as a CSG member. That is, an initial access process between the terminal and the base station is performed. (Eg RACH procedure)

FIG. 9 is an exemplary diagram illustrating a process of accessing a base station by a terminal having a CSG list accessible on a closed subscriber group (CSG) cell but not a member of the corresponding cell.

First, the terminal receives system information including the CSG indicator and the CSG identifier from the base station. Thereafter, the terminal first checks the received CSG indicator to confirm whether the access target cell is a CSG cell, and after confirming that the access target cell is a CSG cell, the terminal itself checks the received CSG identifier and the target cell itself. Verify that you are a member of CSG. However, as a result of checking the CSG identifier, since the terminal itself is not a CSG member of the target cell, the terminal regards the target cell as an access restricted cell and does not perform an initial access procedure between the terminal and the base station.

 FIG. 10 is an exemplary diagram illustrating a process of accessing a base station by a terminal that does not have a list of accessible CSGs in a cell on a closed subscriber group (CSG) cell.

First, the terminal receives system information including the CSG indicator and the CSG identifier from the base station. Thereafter, the terminal first checks the received CSG indicator to determine whether the access target cell is a CSG cell. However, since the terminal does not have a list of CSG accessible to the cell, the terminal regards the target cell as an access restricted cell and does not perform an initial access procedure between the terminal and the base station.

 11 is an exemplary diagram illustrating a process of accessing a base station of all terminals on a non-CSG (Closed Subscriber Group) cell.

First, the terminal receives system information including the CSG indicator from the base station. Thereafter, the terminal checks the received CSG indicator to determine whether the access target cell is a CSG cell. After the confirmation procedure, since the access target cell is identified as a normal cell, the terminal regards the access target cell as a normal cell and performs an initial access procedure between the terminal and the base station. Here, the confirmation that the target cell is a normal cell may inform that the base station does not send the CSG indicator in the system information. That is, if it is confirmed that there is no information on the CSG indicator in the system information received from the base station, the terminal regards the target cell as a normal cell and performs an initial access procedure with the base station.

12 is an exemplary diagram illustrating a process of accessing a base station of a CSG subscriber member terminal on a hybrid cell.

First, the terminal receives system information including the CSG indicator and the CSG identifier from the base station. Thereafter, the terminal determines whether the access target cell is a hybrid cell based on the received CSG indicator and the CSG identifier. Thereafter, the terminal sees the received CSG identifier and confirms that the UE is a CSG member of the target cell. If so, the terminal performs an initial access procedure with the base station as a CSG member. Here, if the CSG indicator is not included in the received system information, the terminal regards the target cell as a normal cell and performs an initial access procedure with the base station.

13 is an exemplary diagram illustrating a process of accessing a base station by a non-CSG subscriber member on a hybrid cell.

First, the terminal receives system information including the CSG indicator and the CSG identifier from the base station. Thereafter, the terminal determines whether the access target cell is a hybrid cell based on the received CSG indicator and the CSG identifier. Thereafter, the terminal sees the received CSG identifier and confirms that the UE is a CSG member of the target cell. If not, the terminal regards the target cell as a normal cell and performs an initial access procedure with the base station. In this case, if the CSG indicator is not included in the received system information, the terminal regards the target cell as a normal cell and performs an initial access procedure with the base station.

Hereinafter, a terminal according to the present invention will be described.

The terminal according to the present invention includes all types of terminals that can use a service that can exchange data with each other over the air. That is, the terminal according to the present invention is a mobile communication terminal capable of using a wireless communication service (for example, user equipment (UE), mobile phone, cellular phone, DMB phone, DVB-H phone, PDA phone, and PTT phone, etc.) It is a comprehensive meaning including laptops, laptops, laptops, digital TVs, GPS navigation, handheld game consoles, MP3s, and other consumer electronics.

The terminal according to the present invention may include a basic hardware configuration (transmitter / receiver, processor or controller, storage, etc.) required to perform functions and operations for efficient system information reception illustrated in the present invention.

The method according to the invention described thus far can be implemented in software, hardware, or a combination thereof. For example, the method according to the present invention may be stored in a storage medium (eg, internal memory of a mobile terminal or base station, flash memory, hard disk, etc.), and may be stored in a processor (eg, mobile terminal or base station). Code or instructions within a software program that can be executed by an internal microprocessor).

In the above, the present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary and will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible. . Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a network structure of E-UTRAN, which is a mobile communication system to which the present invention and the present invention are applied.

Figure 2 is an exemplary view showing a control plane structure of a radio interface protocol between the terminal and the E-UTRAN in the prior art.

3 is an exemplary diagram illustrating a user plane structure of a radio interface protocol between a terminal and an E-UTRAN in the prior art.

4 is an exemplary diagram illustrating a procedure for UE operation of selecting a cell in an idle mode.

 5 is an exemplary diagram illustrating a network structure of an E-UTRAN operating an H (e) NB using an H (e) NB gateway (GW).

6 is a first exemplary diagram illustrating a method of confirming an access mode of a base station by a terminal according to the present invention.

7 is a second exemplary diagram illustrating a method of confirming an access mode of a base station by a terminal according to the present invention.

8 is an exemplary diagram illustrating a base station access process of a CSG subscribed member terminal on a closed subscriber group (CSG) cell.

FIG. 9 is an exemplary diagram illustrating a process of accessing a base station by a terminal having a CSG list accessible on a closed subscriber group (CSG) cell but not a member of the corresponding cell.

 FIG. 10 is an exemplary diagram illustrating a process of accessing a base station by a terminal that does not have a list of accessible CSGs in a cell on a closed subscriber group (CSG) cell.

 11 is an exemplary diagram illustrating a process of accessing a base station of all terminals on a non-CSG (Closed Subscriber Group) cell.

12 is an exemplary diagram illustrating a process of accessing a base station of a CSG subscriber member terminal on a hybrid cell.

13 is an exemplary diagram illustrating a process of accessing a base station by a non-CSG subscriber member on a hybrid cell.

Claims (14)

A method of determining an access mode of a cell in a wireless communication system, In determining whether the access mode of the cell is the first mode, in the first mode, only one or more terminals in a specific subscriber group are allowed to access. If the access mode of the cell is determined to be an access mode other than the first mode, confirming the existence of a subscriber group identity; And If the subscriber group identifier is present, in the step of considering the access mode of the cell as the second mode, in the second mode, one or more terminals or all terminals of the cell are selectively connected in the specific subscriber group. Method for determining the connection mode of a cell on a wireless communication system, characterized in that it is permitted. 2. The method of claim 1, wherein the cell in the first mode is a Closed Subscriber Group (CSG) cell and the cell in the second mode is a hybrid cell. 3. The method of claim 2, wherein a cell type indicator is used to determine whether the cell's connection mode is the first mode or not. 4. The method of claim 3, wherein the cell type indicator is a Closed Subscriber Group (CSG) indicator and the subscriber group identifier is a CSG identifier. 5. The method of claim 4, wherein the hybrid cell comprises the CSG indicator set to 'FALSE' and broadcasts the CSG identifier. A method of determining an access mode of a cell in a wireless communication system, In the determining of whether the terminal supports a specific access mode of the cell, in the specific access mode, one or more terminals or all terminals of the cell are selectively allowed to access a specific subscriber group. If it is determined that the terminal supports the specific access mode, checking a subscriber group identity; And If it is determined that the terminal does not support the specific access mode, the step of identifying a subscriber group indicator to determine the access mode of the cell characterized in that it comprises the step of a cell in a wireless communication system How to determine the connection mode. 7. The method of claim 6, wherein the cell of the particular access mode is a hybrid cell. 7. The method of claim 6, wherein the accessor group identifier is a Closed Subscriber Group (CSG) identifier. 7. The method of claim 6, wherein the accessor group indicator is a closed subscriber group (CSG) indicator. A method of determining an access mode of a cell in a wireless communication system, Providing information and a subscriber group identifier to a terminal to determine an access mode of the cell, wherein the information indicates that the terminal is not a specific access mode, and the specific access mode is one or more in a specific subscriber group. A method of determining a cell's connection mode on a wireless communication system, comprising allowing terminals to be connected only. 12. The method of claim 10, wherein the cell in the particular access mode is a Closed Subscriber Group (CSG) cell. 11. The cell access mode of claim 10, wherein the information indicating that the terminal is not in the specific access mode is provided to the terminal by transmitting a subscriber group indicator. How to judge. 13. The method of claim 12, wherein the accessor group indicator is set to 'FALSE'. 12. The cell connection of claim 10, wherein the information indicating that the terminal is not the specific connection mode is provided to the terminal by not sending a subscriber group indicator. How to determine the mode.

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