KR20050014620A - Method for supporting mobility of user equipment using service availability information of multimedia broadcast/multicast service - Google Patents

Abstract

PURPOSE: A portability supporting method of a terminal by using SA(Service Availability) information of an MBMS(Multimedia Broadcast/Multicast Service) is provided to previously perceive whether an MBMS is available through an MCCH(Main Control Channel), and to selectively carry out an RRC setup if the MBMS is available, thereby reducing an overhead caused by an unnecessary RRC setup. CONSTITUTION: An RNC(511) receives a session start message(531), and decides whether an MBMS is an NSA(Non Service Area) or an SA(Service Area) or the MBMS cannot be provided(541). The RNC(511) transmits an MBMS call message to UEs(501,502)(551), and performs a counting procedure for available terminal numbers(561). The RNC(511) notifies the UEs(501,502) of RB(Radio Bearer) information(562). If an RB setup procedure is terminated, the UEs(501,502) receive the MBMS(563). The RNC(511) periodically transmits a service availability message through an MCCH(571).

Description

Method for supporting mobility of terminal using service validity information of multimedia broadcasting / multicast service {METHOD FOR SUPPORTING MOBILITY OF USER EQUIPMENT USING SERVICE AVAILABILITY INFORMATION OF MULTIMEDIA BROADCAST / MULTICAST SERVICE}

The present invention relates to a method for providing a multimedia broadcast / multicast service (hereinafter referred to as MBMS service) in a mobile communication system, and in particular, a service availability for an MBMS service (hereinafter referred to as SA). It relates to a method for transmitting and receiving information.

Due to the development of communication technology and increasing user demands, mobile communication systems using Code Division Multiple Access (CDMA) technology are not only used for voice services but also for circuit communication and packet communication. It is evolving to support multimedia multicasting services that transmit data. In order to support multimedia multicasting communication, third generation standardization organizations provide a multimedia broadcast / multicast (MBMS) service that provides the same data from one data source to a plurality of user equipments (hereinafter referred to as UEs). Various criteria are provided to provide.

1 is a block diagram of a mobile communication system for a typical MBMS service. Here, a configuration example in which MBMS service is applied to 3GPP (3rd Generation Project Partnership) system, which is a standard of 3G asynchronous mobile communication based on Global System for Mobile Communications (GSM) and General Packet Radio Services (GPRS), is illustrated.

Referring to FIG. 1, UEs 101, 102, 103, 104, 105, 106, 107, and 108 refer to terminal devices capable of receiving MBMS data, and cells 111, 112, and 113. ) Denotes a cell area of the base station where the UEs 101 to 108 are located. Node B 121 is a base station for exchanging radio signals and wired signals according to the 3GPP standard, and provides MBMS to UEs 101 to 108 belonging to cells 111, 112, and 113.

A radio network controller (hereinafter referred to as RNC) 131 is a radio network controller for controlling a plurality of Node Bs. The Node B 121 and a plurality of Node Bs supporting MBMS (MBMS multimedia data) are supported. Control wireless channels established between the Node Bs and the UEs. The RNC 131 and the Node B 121 controlled by the RNC 131 constitute a UMTS Terrestrial Radio Access Network (hereinafter referred to as UTRAN), and the UTRAN forms UEs 101 to 108. It is responsible for connecting to the core network (hereinafter referred to as CN).

The Serving GPRS Support Node (SGSN) 141 controls the services of each of the MBMS subscribers. As a representative example, it manages service billing data of each subscriber and selectively provides multimedia data to a specific RNC. A Home Location Register (HLR) 151 is connected to the SGSN 141 to authenticate subscribers. The Gateway GPRS Support Node (GGSN) 161 provides MBMS data to be supplied to the UEs 101 to 108 through a broadcast / multicast service center (BM-SC) 181 and a border gateway (BG) 171. (Contents Provider) 191 and the Multicast Broadcast Sources (Multicast Broadcast Sources) (192, 193) is provided and transmitted to the SGSN 141, the management of the mobile situation of the UEs (101 to 108) and UEs (101 to 108) manages the quality of service for the MBMS serviced. The content provider 191 and the multimedia broadcast sources 192 and 193 indicate the source of MBMS data transmission.

The BG 171 receives MBMS data from the multicast broadcast source 192 in the network not currently managed by the service provider, and delivers the MBMS data to the GGSN 161. The BM-SC 181 receives the MBMS data from the content provider 191 and delivers it to the GGSN 161, and the authentication of the content provider 191, determination of the quality of service of the MBMS, error correction function for the loss of MBMS data, It informs the charging for the content provider 191 and the MBMS service currently being served for the UEs 101 to 108.

The MBMS data stream passes through the BM-SC 181 from the content provider 191, through the BG 171 from the multicast broadcast source 192 of the external network, or directly from the multicast broadcast source 193. It is transmitted to the GGSN 161 and is communicated to the UEs 101 to 108 in the cells 111, 112, and 113 through the Node B 121 under the control of the SGSN 141 and the RNC 131.

Although not shown, there may be multiple SGSNs and multiple RNCs connected to each SGSN for one MBMS service. The SGSN and the RNC perform selective data transmission to the RNC and the Node B, respectively, and store a list of nodes (List of RNC in SGSN, Node B in RNC) for data transfer.

FIG. 2 is a message flow diagram illustrating a typical multimedia broadcasting / multicast service procedure, in which a terminal 201 receiving an MBMS service and an RNC 211 for an MBMS service are described to explain a procedure in which an MBMS service is provided in a specific cell. ) And only the signal flow between SGSN 221 for MBMS service.

Referring to FIG. 2, in step 231, the SGSN 221 transmits basic information about a specific MBMS service to the terminal 201 through the RNC 211, for example, the specific MBMS service identifier and the like of the MBMS service. Announcement is available. If there is a service to be received from among the MBMS services recognized through the announcement process 231, the terminal informs SGSN that the UE joins the MBMS service through the RNC. The join process 241 is performed by the terminal notifying the SGSN of the identifier of the MBMS service to be received by the terminal and notifying the terminal whether the MBMS service can be received after the SGSN performs authentication or the like. . The SGSN stores a list and locations of terminals to receive a specific MBMS service through the join process 241.

In the future, when the BM-SC notifies the start of the MBMS service, in step 251, the SGSN transmits a session start message to the RNC in which the terminal that performed the join process 241 is located. In step 252, the RNC sends an MBMS call message to call the terminal to receive the MBMS service. In order to transmit the MBMS paging message, a plurality of terminals joined to the corresponding MBMS service must be paging, and thus the process 252 is called group paging in a meaning that is different from the existing paging procedure.

In step 261, the terminal transmits a notification response to the call. Through the transmission process 261 of the response message, the RNC determines the number of terminals to receive the MBMS service for each cell and determines the type of radio channel of the corresponding cell. If the number of terminals to receive the MBMS service is not smaller than a predetermined predetermined threshold value, the MBMS service is provided through a common channel by a point-to-multipoint (hereinafter referred to as PtM) method. Point, PtP (hereinafter referred to as PtP) method to establish the RRC (Radio Resource Control) connection for each terminal and configure the dedicated channel to provide the MBMS service.

In step 271, the RNC transmits MBMS RB (Radio Bearer) information to the terminal. The MBMS RB information includes radio channel information to be provided with MBMS service, for example, Orthogonal Variable Spreading Factor (OVSF) code information, transport format information, radio link control (RFC) information, Packet data collision control (PDCP) information and the like. In step 281, the terminal receives an MBMS service provided according to the MBMS RB information.

MBMS RB information to be used when providing a specific MBMS service in a specific cell becomes valid for all UEs that want to receive the MBMS service in the cell. Therefore, it is efficient that control signals related to MBMS are transmitted through a common control channel configured in a cell. In 3GPP, the MBMS control signal is periodically transmitted through a logical channel called an MBMS Control Channel (hereinafter referred to as MCCH).

3A and 3B illustrate MBMS control messages periodically transmitted through the MCCH for MBMS service. The following MBMS control messages are for MBMS service of a terminal in PMM (ID) mode and PMM CONNECTED mode.

3A illustrates the transmission of the MBMS service validity message 301, which is used to notify the terminal from the radio network controller of the validity information of the MBMS service during the MBMS service.

3B illustrates the transmission of the MBMS RADIO BEARER INFORMATION message 302. The message 302 is an MBMS Traffic Channel (MBMS Traffic Channel: MTCH) in which MBMS data is transmitted to a terminal by a wireless network controller. Radio bearer (hereinafter, referred to as RB) information. When the MBMS service is serviced by PtP, it is not meaningful to inform the RB information through the MCCH since the RB is set for each terminal. Therefore, the RB information of the MBMS radio bearer information message 302 is valid only for an MBMS service serviced by PtM. The MBMS radio bearer information message further includes information about an MBMS service ID, a logical channel, a transport channel, and a physical channel.

4 shows an example of a mobile terminal receiving a multimedia broadcasting / multicast service, wherein reference numerals 401 and 402 denote cells for MBMS services, 411 denote terminals for receiving MBMS services, and 411 denote MBMS C services. It indicates that the receiving terminal moves from cell 1 401 to cell 2 402.

Referring to FIG. 4, cell 1 401 and cell 2 402 indicate a cell for MBMS service, and terminal 411 indicates a terminal receiving MBMS service, and the terminal indicates cell 2 in cell 1 401. Move to 402. Cell 2 becomes the destination cell of the terminal 411. If the terminal of the terminal 411 is currently receiving only one MBMS service, the state of the MBMS service in the mobile destination cell may be defined as three as follows. The first may be an area in which the destination cell does not support the service (hereinafter referred to as NSA). The second is an area in which the target cell supports the service, but currently does not support the service temporarily (Out of Service Area: hereinafter referred to as OSA). A specific example of the second case may be due to lack of resources in a cell. The third indicates an area where the service can be serviced in the destination cell (hereinafter, referred to as SA). Third, the current service is serving in ptp / ptm in cell 2, the destination cell, or in the absence of the terminal requesting the service in the cell, but the MBMS session is started. Means local.

When the terminal 411 moves to cell 2, it establishes an RRC connection and requests a service currently received by the terminal. However, in cell 2, if the service is in the scenario first (NSA) or second state (OSA), even if the service is requested by establishing an RRC connection, the service is not received. In other words, it causes an overhead of useless RRC connection establishment, and also moves from cell 1 to cell 2 only when the RRC connection establishment is established that the service is NSA or OSA, and a response to the service request from the RNC comes. In this case, the terminal may perform an operation such as relocation to a cell in which the service is available. A terminal receiving a service belonging to an NSA or OSA has a problem of increasing the overhead and service delay time for establishing the RRC connection described above by performing a procedure for requesting a service by setting an unnecessary RRC connection.

Accordingly, the present invention, which was devised to solve the problems of the prior art operating as described above, provides information on the validity of MBMS service in each cell to a mobile station in a mobile communication system providing a multimedia broadcasting / multicast (MBMS) service. Provide a way to notify.

According to the present invention, a mobile communication system providing a multimedia broadcasting / multicast (MBMS) service requests a MBMS service or selects another cell after recognizing that a terminal enters a cell (NSA, OSA) that is not capable of MBMS service. Provide a way to.

The present invention indicates whether the MBMS service is NSA or NSA in each cell in a mobile communication system providing a multimedia broadcasting / multicast (MBMS) service. It provides a method of notifying information to a terminal.

According to the present invention, in a mobile communication system providing a multimedia broadcasting / multicasting (MBMS) service, a terminal provides information indicating whether an MBMS service is NSA in each cell or an SA, but does not provide current service due to lack of resources (OSA). Provides a way to notify.

The present invention provides a method of transmitting validity information of an MBMS service by using a service availability message transmitted through an MCCH .

A preferred embodiment of the present invention, which is invented to achieve the above object, comprises a wireless network controller and a plurality of base stations connected to the wireless network controller and serving terminals located in at least one cell. In the system, Method for transmitting service validity information for multimedia broadcasting / multicast service by the wireless network controller,

Determining whether the multimedia broadcasting / multicast service is valid and generating a service validity message including validity information of the multimedia broadcasting / multicast service;

And transmitting the multimedia broadcast / multicast service to terminals to be received.

Another embodiment of the present invention, in a mobile communication system including a wireless network controller and a plurality of base stations connected to the wireless network controller to service terminals located in at least one cell, multimedia broadcasting by each of the terminals A method for receiving service validity information for a multicast / multicast service,

Receiving a service validity message including validity information on the multimedia broadcasting / multicast service from the wireless network controller;

And determining whether the multimedia broadcasting / multicast service to be received is valid according to the validity information.

1 is a block diagram of a mobile communication system for a conventional multimedia broadcasting / multicast service (MBMS).

2 is a message flow diagram illustrating a typical multimedia broadcast / multicast service procedure.

3A and 3B illustrate control messages transmitted over a Multimedia Broadcast / Multicast Service Control Channel (MCCH).

4 is a diagram illustrating a movement of a terminal provided with a multimedia broadcasting / multicast service.

5 is a diagram illustrating a method for transmitting information on the validity of a multimedia broadcast / multicast service through a control channel (MCCH) according to an embodiment of the present invention.

6 is a format form of a service validity message transmitted through MCCH

7 is a flow diagram illustrating operation of a radio network controller (RNC) initially transmitting an MBMS call message in accordance with a preferred embodiment of the present invention.

8 is a flowchart illustrating an operation of a radio network controller (RNC) for transmitting a service validity message following the transmission of the initial MBMS call message of FIG. 7 according to a preferred embodiment of the present invention.

9 and 10 are flowcharts illustrating operations of a terminal (UE) for determining whether a service is valid according to an exemplary embodiment of the present invention.

11 is a flowchart illustrating an operation of a radio network controller (RNC) for periodically transmitting a service validity message according to a preferred embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail the operating principle of the preferred embodiment of the present invention. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

The present invention described below is MBMS periodically transmitted through the MCCH to transmit information on the service validity from the radio network controller (RNC) to the terminal (UE) in a mobile communication system providing a multimedia broadcasting / multicast (MBMS) service Use control messages.

There are three states for the MBMS service in the destination cell to which the terminal moves. In the first case, the target cell is a region that does not support MBMS service, that is, a non-service area (NSA). In the second case, the target cell supports the MBMS service, but at the time when the terminal moves, due to lack of resources in the cell, the temporary This is the case where the service cannot be provided, that is, an out of service area (OSA), and the third case is the case where the target cell can provide the MBMS service, that is, an SA (service area).

If the target cell is NSA or OSA, the terminal determines that it cannot be provided even if it requests the MBMS service by setting up the RRC connection and does not perform the RRC connection setup. If the target cell is an NSA, no procedure for calling the MBMS is necessary because it does not provide MBMS service.However, if the target cell is an OSA, the procedure for MBMS call is needed because the MBMS service must be provided when resources are available. . The target cell, which is an SA, is providing the MBMS service to PtP or PtM or is not currently providing the service due to the absence of the terminal requesting the MBMS service, but since the MBSM session is started, it can start as soon as the terminal requests the MBMS service.

5 is a message flow diagram illustrating an operation of notifying a terminal through MCCH of information on the validity of an MBMS service according to an exemplary embodiment of the present invention. Here, reference numerals 501 and 502 denote terminals receiving MBMS services, 511 denotes RNCs for MBMS services, and 521 denotes SGSN.

Referring to FIG. 5, in step 531, the RNC 511 receives a session start message from the SGSN 521. Since the session start message includes parameters such as an MBMS service ID and a quality of service (QoS), the RNC refers to the parameters in step 541 so that the MBMS service is located in a certain region (i.e., cell). NSA or SA, or whether the MBMS service cannot be provided because the current resource is insufficient in a specific cell (OSA). The shortage of resources for a particular MBMS service can be determined by checking whether an OVSF code that can satisfy the QoS of the session start message is currently available.

In step 551, the RNC transmits an MBMS call message to the terminals 501 and 502 for the MBMS service. The MBMS call message is also referred to as a notification. The MBMS call message indicates that an event for the MBMS service has occurred, and includes an MBMS service ID, a cause value, an NSA / SA indicator, a resource availability indicator, and parameters required for effective terminal counting. . The coarse value is a value indicating that 551 has occurred due to the thin line start message generated in 531. In addition, an optional value (hereinafter referred to as OP) or a conditional value (CV) may further include a resource availability identifier and parameters required for terminal counting. The values of the NSA / SA indicator and the resource availability indicator are set according to the resource and service state of the cell in which the corresponding MBMS call message is actually transmitted.

That is, the MBMS paging message can be transmitted even while the MBMS service is in progress, and has corresponding parameters according to which service event has occurred and which MBMS control message should be received.

If it is determined that a particular MBMS service is an NSA, the MBMS call message includes only the corresponding service ID and cause value (Cause value and NSA / SA indicator), that is, resource availability indicator and parameters necessary for effective terminal counting are conditional. On the other hand, if the specific MBMS service is OSA, the MBMS call message includes only the corresponding service ID, Cause value, NSA / SA indicator, and resource availability indicator. If the MBMS service is an SA, all parameters must be included.

When each of the terminals 501 and 502 receives the MBMS call message, each of the terminals 501 and 502 performs a corresponding operation when the desired MBMS service is NSA, OSA or SA according to a parameter included in the MBMS call message. If the desired MBMS service is NSA and cell reselection is possible, the terminal reselects and moves another cell capable of the desired MBMS service, and if the cell reselection is not possible and there is no other desired MBMS service in the cell, Abandon the reception of MBMS service.

In addition, if the desired MBMS service is OSA and cell reselection is possible, the terminal reselects and moves to another cell capable of the MBMS service, and if the cell reselection is not possible, when resources are available while monitoring the MCCH in the cell. If the user waits until there is a request from the user, the MBMS service is abandoned in the corresponding cell. The terminal may know whether the resource is available again, that is, whether the corresponding cell has become an SA by receiving the MBMS call message or additionally receiving the MBMS service validity message transmitted through the MCCH according to the scheduling for the MCCH.

As described above, the present invention includes the NSA / SA indicator and the resource availability indicator in the MBMS call message to provide the terminal with information on whether the MBMS service is available in the cell, so that the terminal can take an appropriate operation based on the information. do.

On the other hand, if the desired MBMS service is SA, the terminal performs the following processes as described in the prior art of FIG. That is, the processes 561, 562, and 563 represent an operation flow when the MBMS service is an SA. The RNC 511 performs a counting procedure in step 561 if the counting of the number of valid terminals is necessary, and informs the terminals 501 and 502 of the determined RB information in step 562. If the number of terminals in the RRC connected state (that is, valid) maintained by the RNC 511 is large enough to receive PtM service, the RNC does not perform the counting of step 561 and immediately RB information of the PtM service mode. Is determined and transmitted in step 562. When the RB setting procedure is finished, the terminal can receive the MBMS service in step 563.

After the MBMS service is started, in step 571, the RNC 511 periodically transmits information on NSA, OSA, and SA of the MBMS services in a service validity message through the MCCH to support mobility of the terminal. The service validity message transmitted through the MCCH includes MBMS service identification information, resource availability indication information, current service mode information, and mapping information with an MBMS Radio Network Temporary Identifier (mRNTI).

The MBMS service identification information represents all MBMS services that are OSA and SA. That is, the fact that the specific MBMS service ID cannot be found in the service validity message means that the corresponding MBMS service is not available in the current cell (NSA). Upon receiving the service validity message, the terminal may read the resource availability indication information and determine whether the MBMS service is OSA or SA. If a specific MBMS service is an SA, information on the current service type is included. The information on the service type indicates whether the corresponding MBMS service is served in PtP type, PtM type in the current cell, or whether the MBMS service session is started but the terminal requesting the service does not exist in the cell (no UE). .

If the PtM type, the terminal finds the RB information from the radio bearer information message transmitted through the MCCH, and receives the corresponding MTCH to receive the MBMS service. If the PtP type, the RRC connection is established to request the MBMS service. On the other hand, if there is no UE, this indicates that there is no terminal requesting the MBMS service in the current cell, and thus establishes an RRC connection to request the MBMS service or perform another designated operation. Here, if the operation performed by the terminal is the same for the case of the PtP type and the case of the no UE, the amount of information transmitted may be reduced by removing the no UE parameter and substituting the PtP parameter.

As described above, the terminal moving to another cell may know whether the MBMS service to be received is NSA, OSA, or SA based on the service validity information. In the case of SA, the terminal currently requests the service. It is possible to know whether it is being serviced by PtP type or PtM type due to the absence of. If it is an NSA, it reselects another cell capable of the MBMS service or abandons MBMS reception in the current cell. If it is OSA, it checks the resource availability by reselecting another cell capable of the MBMS service or periodically receiving the MCCH until the resource becomes available in the current cell. If SA, no appropriate action is taken based on no UE, PtP, and PtM information.

6 illustrates a format of a service validity message transmitted through MCCH according to a preferred embodiment of the present invention. As shown, the service validity information includes a message type and message information elements.

Each of the message information elements includes MBMS service identifier, resource availability indication information, current service type, and mapping information. The service type may indicate no UE, PtP, and PtM. The current service type is a conditional value (CV) included only when a resource is available, and the mapping information is a conditional value (CV) included only when the current service type is PtP or PtM. The resource availability information may be an information bit depending on whether or not there is a resource available, or it may be about resource availability. Detailed description of the resource availability information will be described later.

7 and 8 are flowcharts illustrating an operation of a radio network controller (RNC) for initially transmitting an MBMS call message and a service validity message according to a preferred embodiment of the present invention.

Referring to FIG. 7, when a session start message for MBMS service is received from SGSN in step 601, the RNC determines whether the MBMS service is an SA from parameters included in the session start message in step 611. do.

If the MBMS service is not an SA, the RNC proceeds to step 612 to set the MBMS identifier of the MBMS paging message as the current service ID and to set a 'Cause value' indicating that the session is started and validity. After setting the indicating NSA / SA indicator to the NSA, the MBMS call message is transmitted in step 624. If the MBMS service is an SA, the process 621 checks whether there are enough resources for the MBMS service.

If there are not enough resources to provide the service corresponding to the QoS of the MBMS service, the process proceeds to step 622, where the MBMS identifier of the MBMS call message is set to the service ID and a couse value indicating that the session is started. Set the NSA / SA indicator to OSA and the resource availability indicator to false. The MBMS id, mRNTI, and resource availability of the MBMS service validity message are set to false.

On the other hand, if there are enough resources to satisfy the QoS of the MBMS service, the process proceeds to step 623, where the MBMS identifier of the MBMS call message is set to the service ID, the NSA / SA indicator is SA, and the resource availability indicator is true. true). If it is determined that the number of terminals requesting the MBMS service needs to be counted, parameter values for counting the number of terminals receiving the MBMS service are set to determine the RB type of the MBMS service. In step 624, the MBMS call message is transmitted.

Referring to FIG. 8, FIG. 8 shows a process of setting a service validity message 'initially transmitted following the MBMS call message of FIG. 7. In step 631, the RNC determines whether the MBMS service is the NSA in the cell in which the UE is currently located, and if so, terminates the operation and does not transmit any message related to the MBMS service. On the other hand, if it is not the NSA, the process proceeds to step 632 to determine whether there is a resource that can satisfy the QoS. If the resource is not available, go to Step 671.

In step 632, if there is a resource that can satisfy the QoS, in step 633, the RNC determines whether the number of terminals in the connected mode is large enough to determine the RB type. This is determined by checking whether the number of terminals in the RRC connected mode is smaller than a predetermined threshold value according to the number of terminals counted in the service initialization process. If the number of terminals in the RRC connected mode is not smaller than the threshold, the process proceeds to step 661, where the RB type for the MBMS service is set to PtM and the RB is set. At this time, the service type value of the service validity message is set to PtM.

If the number of terminals in the RRC connected mode is smaller than the threshold in step 633, the process proceeds to step 634 to count the number of terminals currently in service. In step 641, the counting result determines whether the number of terminals to receive the MBMS service is zero. If 0, the process proceeds to step 642 to set the MBMS identifier, mRNTI, resource availability, and service mode value of the service validity message. At this time, the service type is set to no UE.

If the number of terminals to receive the MBMS service is not 0, it is determined in step 651 whether the number of terminals is smaller than a threshold for MBMS service with PtM. The threshold value used herein may be the same as or different from the threshold value in step 633. If it is smaller than the threshold, the process proceeds to step 652 to determine the RB type for the service as PtP and to set the RB information. At this time, the service type value of the service validity message is set to PtP. If the number of terminals is not smaller than the threshold, the process proceeds to step 661, where the RB type for the MBMS service is set to PtM and MBMS RB information is set. At this time, the service type value of the service validity message is set to PtM.

The service validity message set in the processes 630, 642, 652, and 661 is transmitted through the MCCH in step 671, and the MBMS RB information is scheduled and transmitted through the MCCH. It is repeatedly performed for each transmission period of a predetermined service validity message.

9 is a flowchart illustrating the operation of a terminal for receiving a service validity message according to a preferred embodiment of the present invention. Here, an operation flow performed when the mobile terminal reselects a cell is illustrated. That is, the operation shown in FIG. 9 is performed every time the cell is reselected regardless of the start of the session.

Referring to FIG. 9, in step 701, a mobile terminal reads system information through a broadcasting control channel (BCCH). In step 711, the terminal determines whether the information about the MCCH configuration is included in the system information. If the information on the MCCH configuration is not included in the system information, in step 715, the terminal determines that the current cell does not support the MBMS service itself (Non MBMS service Area: NMA). Therefore, another cell supported by the service is searched for and reselected, or the reception of the MBMS service is abandoned. In this case, in order to prevent unnecessary power consumption, the terminal does not monitor the call indication channel by establishing an RRC connection to request a desired MBMS service or by waking up every MBMS discontinuous period.

On the other hand, if the MCCH configuration information is found through the system information, in step 712, the terminal receives the MBMS radio bearer information and the service validity message through the MCCH using the MCCH configuration information. In step 713, the terminal checks whether the MBMS radio bearer information includes the identifier of the MBMS service that the terminal intends to receive. If the identifier of the MBMS service is included, the process proceeds to step 714 where the terminal receives the data of the MBMS service through the MTCH.

If the MBMS radio bearer information does not include the identifier of the MBMS service, in step 721, the terminal checks whether the service validity message includes the identifier of the MBMS service to be received by the terminal. If the desired MBMS identifier is not included, the process proceeds to step 722 to perform a Routing Area (RA) update as necessary. A detailed description of the process 722 will be described later.

On the other hand, if the desired MBMS identifier is included, in step 731, the terminal checks whether resource availability information for the service included in the service validity message is true or false. If the resource availability information is false, in step 732 the terminal determines that the service is an OSA in the current cell. Then, the terminal stays in the current cell while reselecting another cell capable of the MBMS service or by waking up every MBMS discontinuous reception period to monitor the call indication channel. On the other hand, if the resource availability information is true, it is determined in step 741 whether the service type for the service is no UE.

If no UE, in step 742, establishes an RRC connection and requests the service. Referring to step 742 in more detail, the idle mode terminal performs the RRC connection setup procedure. The terminal in the CELL_FACH or CELL_PCH state, which monitors a forward access channel (FACH) or a paging channel (PCH), may transmit a PtP radio bearer by using a cell update confirmation message or a radio bearer setup message. Receive information. The terminal in the URA_PCH state performs a cell update procedure and receives PtP radio bearer information by a cell update confirmation message or a radio bearer setup message. Finally, the terminal in the CELL_DCH state, which is a state for monitoring a dedicated channel (DCH), receives PtP radio bearer information by handover.

On the other hand, if no UE in step 741, it is determined whether the service type is PtP in step 751. If it is PtP, the process proceeds to step 752 to establish an RRC connection and request the service. Referring to step 752 in more detail, the idle mode terminal performs the RRC connection establishment procedure. The terminal in the CELL_FACH or CELL_PCH state receives the PtP radio bearer information by the cell update confirmation message or the radio bearer setup message. The terminal in the URA_PCH state performs a cell update procedure and receives PtP radio bearer information by a cell update confirmation message or a radio bearer setup message. Finally, the terminal in the CELL_DCH state receives PtP radio bearer information by handover.

In step 753, the terminal receives data of a desired MBMS service through DTCH using the received PtP radio bearer information.

If not PtP, in step 761, it is determined whether the service type is PtM. If neither PtM is determined to be an error, the process ends. If the service type is PtM, a radio bearer information message is received through an MCCH in operation 762, and data of a desired MBMS service is received through an MTCH activated by the radio bearer information in operation 763. .

10 is a flowchart illustrating a case where an RA update is performed after receiving a service validity message of an MBMS service from a terminal.

Referring to FIG. 10, if the MBMS service to be received by the terminal is not valid, the process proceeds to step 771 to determine whether a routing area (RA) update is necessary. If the RA update is not required or the RA update has already been performed, in step 773, the terminal determines that the service is the NSA in the current cell, finds and reselects another cell supported by the service, or abandons reception of the MBMS service. do. In this case, the terminal does not monitor the call indication channel by waking up every MBMS discontinuous reception period.

On the other hand, if the RA update is required, in step 772, the terminal sends a message requesting the RA update to the RNC and waits for the RA update confirmation message. In step 781, the terminal checks whether the MBMS service information is included in the RA update confirmation message received from the RNC.

If the RA update confirmation message includes the MBMS service information, in step 782, the terminal operates according to the service validity information read from the RA update confirmation message. That is, if the service is an NSA or OSA, it determines whether it is NSA or OSA by the RA update confirmation message and then performs a corresponding operation. If the service is an SA, the PtP RB is set according to the PtP RB information obtained by the RA update confirmation message for the service.

On the other hand, if the MBMS service information is not included, it operates according to the service validity information read from the first service validity message received after the RA update confirmation message in step 783. That is, if the service is an NSA or OSA, the MBMS service validity message determines whether the service is NSA or OSA, and then performs a corresponding operation. If the service is an SA, PtP RB information is received by the RB configuration message or the MBMS service is requested.

Here, if the desired MBMS identifier is not included in the received service validity message after performing the routing area update of FIG. 10, and the process proceeds to step 771, the terminal determines that the routing area update is not necessary. . This is to prevent unnecessary routing area updates from being repeatedly performed.

11 is a flowchart illustrating an operation of a radio network controller (RNC) for periodically transmitting a service validity message during a service according to a preferred embodiment of the present invention.

In 801, it is checked whether the MBMS service is in the NSA region. If at 801 the service is an NSA region, go to 851. This means that if the service is an NSA region, it does not include the service ID in the service validity message. If the service is not in the NSA region at 801, then check in 811 if there are enough resources for the service. If the resource for the service is not sufficient at 811, the information included in the service validity message is set at 812. The mapping information between the service ID and the mRNTI value will be included, and the resource availability indicator is set to false. If it is determined at 811 that the resources for the service are sufficient, it is checked at 821 whether the service type is no UE. 821, if the service type is no UE, the service validity message will include mapping information between the service ID and the mRNTI value at 822. The resource availability indicator is set to true, and the service type is set to no UE. If the service type is no UE at 821, it is checked at 831 whether the service type is ptp. If the service type is ptp at 831, the service validity message will include mapping information between the service ID and the mRNTI value at 832. The resource availability indicator is set to true, and the service type is set to ptp. If the service type is not ptp at 831, this means that the service type is ptm. At 841, the service validity message will contain mapping information between the service ID and the mRNTI value. The resource availability indicator is true and the service type is set to ptm. do. If the information of the service validity message is set according to the case of no UE, ptp, ptm of OSA, SA at 812, 822, 832, and 841, it is changed to 801 until the information of all available services in the cell is set through 851. Go ahead and repeat. This is because the service validity message is not a message for one specific service, but includes information about multiple services as many as the number of available services in a cell. In step 851, if the step of setting the information of the service validity message for all available services in the cell is finished, the service validity message is transmitted at 861.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by those equivalent to the scope of the claims.

In the present invention operating as described in detail above, the effects obtained by the representative ones of the disclosed inventions will be briefly described as follows.

According to the present invention, in a mobile communication system providing a multimedia broadcasting / multicast service, a terminal can know whether MBMS service is available in advance and can be provided later through MCCH, and selectively performs RRC configuration only when MBMS service is available. Therefore, the overhead of unnecessary RRC connection establishment can be reduced.

Claims (21)

In the mobile communication system including a wireless network controller and a plurality of base stations connected to the wireless network controller and serving terminals located in at least one cell, service validity for the multimedia broadcasting / multicast service by the wireless network controller. In the method for transmitting information, Determining whether the multimedia broadcasting / multicast service is valid and generating validity information for the multimedia broadcasting / multicast service; And transmitting the service validity information to terminals that want to receive the multimedia broadcast / multicast service. The method of claim 1, wherein the service validity information, And a service identifier, resource availability indication information, and service type information, wherein the service type information is a conditional value included only when a resource for the multimedia broadcasting / multicast service is available. The method of claim 1, wherein the service validity information, And a value indicating whether the wireless network controller is the multimedia broadcasting / multicast service available area or service unavailable area or whether service is available but service is not available. The method as claimed in claim 2, wherein the service type information indicates one of point-to-point mode (PtP) transmission, point-to-multimode (PtM) transmission, and no UE. The method of claim 1, wherein the transmitting of the service validity information comprises: And if a session start for the multimedia broadcast / multicast service is requested, generating and transmitting a service validity message including the service validity information. The method of claim 1, wherein the transmitting of the service validity information comprises: And periodically generating and transmitting a service validity message including the service validity information during the multimedia broadcasting / multicast service. The method of claim 1, wherein the transmitting of the service validity information comprises: And when a session start for the multimedia broadcast / multicast service is requested, transmitting a call message including the service validity information to terminals to receive the multimedia broadcast / multicast service. The method of claim 1, wherein the transmitting of the service validity information comprises: And detecting a movement between the terminals receiving the multimedia broadcast / multicast service, and transmitting a call message including validity information of the multimedia broadcast / multicast service to the mobile terminals. The method as claimed in claim 7 or 8, wherein when the multimedia broadcast / multicast service is invalid, the call message includes the multimedia broadcast / multicast service identifier and the service validity indication information. . The method according to claim 7 or 8, wherein when the multimedia broadcast / multicast service is temporarily invalid, the paging message includes the multimedia broadcast / multicast service identifier, the service validity indication information, and the resource availability indication information. Said method comprising a. The method as claimed in claim 7 or 8, wherein when the multimedia broadcast / multicast service is valid, the paging message includes the multimedia broadcast / multicast service identifier and the service validity indication information. In a mobile communication system including a wireless network controller and a plurality of base stations connected to the wireless network controller to serve terminals located in at least one cell, service validity for a multimedia broadcasting / multicast service by each of the terminals is provided. In a method for receiving information, Receiving service validity information on the multimedia broadcasting / multicast service from the wireless network controller; Determining whether the multimedia broadcasting / multicast service to be received is valid according to the service validity information; And selectively performing a multimedia broadcasting / multicasting service according to the determination result. The method of claim 12, wherein the service validity information, The service identifier, resource availability indication information, and service type information, wherein the service type information is a conditional value included only when a resource is available. The method as claimed in claim 13, wherein the service type information indicates either point-to-point mode (PtP) transmission, point-to-multimode (PtM) transmission, or no UE. The method of claim 14, wherein the determining is performed. Determining whether the service validity information includes a service identifier of the multimedia broadcasting / multicast service to be received, and if so, confirming the resource availability indication information; If a resource for the multimedia broadcast / multicast service to be received is not available, another cell capable of providing the multimedia broadcast / multicast service to be received is reselected or the multimedia broadcast / multicast service to be received is Waiting until valid, Checking the service type information if the resource for the multimedia broadcasting / multicast service to be received is available; If the service type information is no UE or point-to-point (PtP), establishing an RRC connection and requesting the multimedia broadcast / multicast service to be received; And if the service type information is point to point (PtM), acquiring radio bearer information through a broadcast control channel and establishing a broadcast traffic channel. The method of claim 12, wherein the receiving of the service validity information comprises: Receiving system information through a broadcast channel and determining whether the system information includes configuration information of a broadcast control channel; If the configuration information of the broadcast control channel is included, the radio bearer information is received through the broadcast control channel using the configuration information, and if the radio bearer information includes the identifier of the multimedia broadcast / multicast service. Judging, Setting up a radio bearer connection for the multimedia broadcast / multicast service using the radio bearer information if the radio bearer information includes an identifier of the multimedia broadcast / multicast service; And if the radio bearer information does not include the identifier of the multimedia broadcast / multicast service, receiving a service validity message including the service validity information through the broadcast control channel. The method of claim 12, wherein the determining comprises: And analyzing the service validity information if the service validity information includes the identifier of the multimedia broadcasting / multicast service to be received. The method of claim 12, wherein the performing of the multimedia broadcast / multicast service comprises: If the multimedia broadcast / multicast service is invalid, reselect another cell capable of the multimedia broadcast / multicast service, or abandon reception of the multimedia broadcast / multicast service, If the multimedia broadcast / multicast service is temporarily invalid, reselect another cell capable of the multimedia broadcast / multicast service, or wait until resources are available, And if the multimedia broadcast / multicast service is valid, establish a point-to-point radio bearer connection for the multimedia broadcast / multicast service. The method as claimed in claim 12, further comprising the step of performing a routing area update if the service validity information does not include the identifier of the multimedia broadcast / multicast service to be received. The method of claim 19, wherein the performing of the routing area update comprises: If it is determined that the routing area update is not necessary, reselecting another cell capable of providing the multimedia broadcast / multicast service or abandoning the reception of the multimedia broadcast / multicast service; If it is determined that the routing area update is necessary, requesting a routing area update from the wireless network controller and receiving a routing area update confirmation message; Determining whether the MBMS multimedia broadcast / multicast service is valid according to the routing area update confirmation message. The method as claimed in claim 12, wherein the terminal receives signals transmitted through a service control channel every time the cell changes.