CN101507303A - Core network device, wireless communication base station device, and wireless communication method - Google Patents

Abstract

It is possible to provide a core network device, a radio communication base station device, and a radio communication method which can improve the radio resource use efficiency of the entire network without increasing UE battery consumption. According to the devices and the method, a user quantity counting unit (163) of UPE (160) counts the number of UE which have performed a position registration in each position registration area containing a plurality of cells. A user quantity comparing unit (164) selects MCT if the counted UE quantity is not smaller than a predetermined threshold value and SCT if the counted UE quantity is smaller than the predetermined threshold value, thereby appropriately performing switching between SCT and MCT in accordance with the UE quantity. Only when the SCT is selected by the UPE (160), eNB counts the number of users in the cell managed by the local device.

Description

Core network device, wireless communication base station device, and wireless communication method

technical field

The present invention relates to a core network device, a wireless communication base station device and a wireless communication method for providing multimedia broadcast/multicast service (Multimedia Broadcast/Multicast Service: MBMS).

technical field

UMTS (Universal Mobile Telecommunications System: Universal Mobile Communications System) is a third-generation mobile communication system evolved from the European standard GSM (Global System for Mobile Communications: Global System for Mobile Communications). It is based on the GSM core network (CoreNetwork: CN) and WCDMA (Wideband Code Division Multiple Access: Wideband Code Division Multiple Access) wireless connection technology as the basis, will provide further improved mobile communication services as the goal.

UMTS provides MBMS. MBMS is a further expanded service for not only broadcasting multimedia data but also multicasting multimedia data to subscribers of the service. For example, MBMS provides news channels, music channels, movie channels, and the like.

Non-Patent Documents 1, 2 and 3 describe the basic structure and processing steps related to MBMS.

FIG. 1 is a diagram showing a reference architecture (reference architecture) supporting MBMS in a 3GPP UMTS network. As shown in FIG. 1 , UMTS is composed of a terminal (User Equipment: UE) 10, a UTRAN (Radio Access Network) 20, and a core network (Core Network: CN) 30.

UTRAN 20 consists of more than one radio network subsystem (Radio Network Sub-systems: RNS), and the RNS consists of a radio network controller (Radio Network Controller: RNC) 23 and more than one Node B (base station) managed by the RNC 23 21 constitute.

The RNC 23 is responsible for the allocation and management of radio resources, and assumes the role of the access point (Access Point) of the CN 30.

The Node B 21 receives the information forwarded from the physical layer of the UE 10 through the uplink, and forwards the data to the UE 10 through the downlink. Node B 21 acts as an access point between UE 10 and UTRAN.

The UTRAN 20 forms and maintains a radio access bearer (Radio Access Bearer: RAB) for the call between the UE 10 and the CN 30.

The CN 30 requires end-to-end Quality of Service (QoS) requirements for the RAB, and the RAB supports the QoS requirements set by the CN 30. Therefore, the UTRAN 20 can satisfy inter-terminal QoS requirements by configuring and maintaining the RAB.

MBMS is provided through packet switched services. When providing packet switching service, RNC 23 is connected to SGSN (Serving GPRS Support Node: Serving GPRS Support Node) 35 and GGSN (Gateway GPRS Support Node: Gateway GPRS Support Node) 37 of CN 30. The SGSN 35 supports communication with the RNC 23, and the GGSN 37 manages connections with other packet-switched networks like the Internet.

MBMS is a downlink dedicated service that provides a streaming (Streaming) or background (Background) service to multiple UEs 10 using a common or dedicated downlink (downward) channel.

MBMS is divided into a broadcast mode and a multicast mode. In the MBMS broadcast mode, it is easy to forward multimedia data to all users located in the broadcast area (Broadcast Area). In contrast, in the MBMS multicast mode, it is easy to forward multimedia data to a specific user group located in a multicast area (Multicast Area). Here, the broadcast area is an area where broadcast services can be performed, and the multicast area is an area where multicast services can be performed.

A user who wants to receive MBMS receives a service announcement (ServiceAnnouncement) provided by the network. Here, service notification refers to notifying the UE of a list of services to be provided in the future and related information. In addition, the user receives the service notification (Service Notification) provided by the network. Here, the service notification refers to notifying the UE of the information about the forwarded broadcast data.

In addition, users who expect to receive MBMS in multicast mode need to specifically join a multicast subscription group (Multicast Subscription Group). A multicast joining group is a group of users who have gone through the joining procedure.

In order to receive a specific multicast service, users who have joined the multicast joining group may join (Joining) a multicast group, that is, a group of users receiving a specific multicast service. A multicast group is a group of users receiving a specific multicast service. Participation, also known as MBMS multicast activation (Multicast Activation), merges into the multicast group assembled for receiving specific multicast services. Therefore, a user can receive specific multicast data by activating (or participating in) MBMS multicast.

The RNC 23 forwards the MBMS user data to the UE 10 through the Node B 21 via the user plane (user plane) of the UTRAN protocol. UTRAN 20 forms and maintains radio bearers for calls between UE 10 and CN 30 to forward MBMS user data. MBMS radio bearers are only forwarded by the downlink.

The MBMS radio bearer plays the role of forwarding user data of a specific MBMS forwarded from the CN 30 to the UTRAN 20 only for a specific UE.

In addition, in the case of multicast mode, in order to broadcast MBMS user data only to Node B 21 where users exist, UTRAN 20 needs to confirm the existence of UE in the entire service area. Therefore, the UTRAN 20 counts (Counting) the number of UEs. The UTRAN 20 notifies the UE 10 that the counting is being performed when providing MBMS-related information using the MBMS common control channel or when paging a specific MBMS group.

After receiving the information of counting the service from the service notification related to MBMS, in order to notify the UTRAN 20 of the fact that it wants to receive the MBMS, the UE 10 forwards the RRC connection to the UTRAN through the uplink (uplink) common channel Request (Connection Request), set the RRC connection (the connection between the RRC entity of UE 10 and the RRC entity of UTRAN 20). Here, the fact that the UE 10 desires to receive the MBMS is notified to the UTRAN 20 by using the RRC connection request message.

Therefore, the UTRAM 20 recognizes that there is a user requesting a specific MBMS in the cell by identifying the UE 10 that forwarded the RRC connection request message, and sets the MBMS radio bearer even if there is only one user.

However, currently, in 3GPP, the next-generation core network and the radio access network are studied, and correspondingly, the following two transfer methods are also studied as candidates for the specification regarding the MBMS transfer method.

Fig. 2 shows schematic diagrams of two forwarding methods. The first method is called Single Cell Transmission (SCT). As shown on the right side of Figure 2, counting is performed to check the presence of users, and data is transmitted only to cells where users exist. Moreover, when the quality deteriorates at the cell edge, etc., retransmission is provided or the modulation method is changed, thereby improving the user's receiving quality.

The second method is called multi-cell transmission (Multi Cell Transmission: MCT). As shown on the left side of Figure 2, it has nothing to do with whether there are users or not. Multiple cells belonging to the same frequency area (Single Frequency Network: SFN, single carrier network) The base stations transmit data synchronously, and the user's receiving quality is improved through diversity combination among cells.

[Non-Patent Document 1] 3GPP TS 23.246 "3rd Generation Partnership Project; Technical Specification Group Services and System Aspects, MultimediaBroadcast/Multicast Service (MBMS), Architecture and functional description", 2006-06

[Non-Patent Document 2] 3GPP TS 25.346 "3rd Generation Partnership Project, Technical Specification Group Radio Access Network, Introduction of the Multimedia Broadcast Multicast Service (MBMS) in the Radio Access Network (RAN), Stage 2", 2006-06

[Non-Patent Document 3] 3GPP TS 25.331 "3rd Generation Partnership Project, Technical Specification Group Radio Access Network, Radio Resource Control (RRC), Protocol Specification", 2006-06

Contents of the invention

The problem to be solved by the invention

However, in the above method of providing MBMS, MCT or SCT is selected according to the service, so there are the following problems.

In MCT, since multimedia data is only forwarded to the SFN area, when the number of users in the SFN area is small, the amount of data broadcast to cells without users increases, which may reduce the wireless resources of the entire network. Utilization efficiency is reduced.

In addition, in the SCT, counting is performed to forward data only to a specific user group, but the user needs to establish an RRC connection with the Node B for this counting, which consumes battery. Therefore, when the number of users located in a certain area is large, there are users in most of the cells in the area, and the number of UEs that perform unnecessary counting may increase compared with MCT. battery consumption.

The object of the present invention is to provide a core network device, a wireless communication base station device and a wireless communication method, which can improve the utilization efficiency of wireless resources of the entire network without increasing battery consumption of UEs.

Solution to the problem

The structure adopted by the core network device of the present invention includes: a user number counting unit, which counts the number of users participating in the multimedia broadcast/multicast service (MBMS) in units of location registration areas; a user number comparison unit, which counts the number of users The number is compared with the specified threshold. When the number of users is above the threshold, multi-cell forwarding is selected, and when the number of users is less than the threshold, single-cell forwarding is selected. The multi-cell forwarding is, belonging to A plurality of wireless communication base station devices in the same frequency area synchronously forward the forwarding of the MBMS data, and the forwarding of the single cell is that a single wireless communication base station device including users participating in the MBMS forwards the forwarding of the MBMS data in the cell; and The notification unit notifies the selected multi-cell forwarding or single-cell forwarding to the subordinate wireless communication base station apparatus.

The structure adopted by the wireless communication base station device of the present invention includes: an acquisition unit, which acquires an indication of multi-cell forwarding or a single-cell forwarding indication from the core network device, and the multi-cell forwarding is a plurality of wireless communication base station devices belonging to the same frequency region Synchronously forward the forwarding of Multimedia Broadcast/Multicast Service (MBMS) data, the forwarding of the single cell is, the forwarding of the MBMS data is forwarded by a single wireless communication base station device including users participating in MBMS in the community; the counting unit is only in When the instruction of single-cell forwarding is obtained, counting is performed in the cells managed by the device; and the forwarding unit forwards the MBMS data in the cells where the user exists as a result of the counting.

The wireless communication method of the present invention includes: the step of counting the number of users, the core network device counts the number of users participating in the multimedia broadcast/multicast service (MBMS) in units of location registration areas; the step of comparing the number of users counts the counted users The number is compared with the specified threshold. When the number of users is above the threshold, multi-cell forwarding is selected, and when the number of users is less than the threshold, single-cell forwarding is selected. The multi-cell forwarding is, belonging to A plurality of wireless communication base station devices in the same frequency area synchronously forward MBMS data forwarding, and the single cell forwarding means that a single wireless communication base station device including users participating in the MBMS forwards MBMS data forwarding in the cell; notify step, notifying the selected multi-cell forwarding or single-cell forwarding to the wireless communication base station device under the core network device; obtaining step, the wireless communication base station device acquires the indication of the multi-cell forwarding or the An indication of single-cell forwarding; a counting step, counting in the cell managed by the wireless communication base station device only when the single-cell forwarding indication is obtained; and a forwarding step, the result of the counting is counted in the cell where the user exists forward MBMS data.

The effect of the invention

According to the present invention, it is possible to improve the utilization efficiency of radio resources of the entire network without increasing the battery consumption of the UE.

Description of drawings

FIG. 1 is a diagram showing a reference configuration supporting MBMS in a 3GPP UMTS network.

FIG. 2 is a diagram showing the concepts of multi-cell forwarding and single-cell forwarding.

FIG. 3 is a diagram showing the configuration of a network according to Embodiment 1 of the present invention.

FIG. 4 is a block diagram showing the configuration of the MME shown in FIG. 3 .

FIG. 5 is a block diagram showing the configuration of the UPE shown in FIG. 3 .

Fig. 6 is a sequence diagram showing a procedure for joining a multicast joining group.

Fig. 7 is a sequence diagram showing a procedure for starting a session.

Fig. 8 is a sequence diagram showing the mode switching procedure from SCT to MCT.

FIG. 9 is a block diagram showing the configuration of an eNB according to Embodiment 1 of the present invention.

FIG. 10 is a flowchart showing a recounting procedure in the eNB according to Embodiment 2 of the present invention.

FIG. 11 is a block diagram showing the configuration of an eNB according to Embodiment 2 of the present invention.

FIG. 12 is a block diagram showing the configuration of a UPE according to Embodiment 3 of the present invention.

Fig. 13 is a sequence diagram showing a session start procedure according to Embodiment 3 of the present invention.

14 is a sequence diagram showing an inquiry of the MBMS provision status between eNBs according to Embodiment 4 of the present invention.

FIG.15 is a block diagram showing the configuration of a UE according to Embodiments 5 and 6 of the present invention.

FIG. 16 is a block diagram showing the configuration of an eNB according to Embodiments 5 and 6 of the present invention.

Detailed ways

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)

FIG. 3 is a diagram showing the configuration of a network according to Embodiment 1 of the present invention. The structure of the network shown in FIG. 3 includes a terminal (User Equipment: UE) 100, a wireless base station device (Evolved NodeB: eNB) 120, a mobility management device (Mobility Management Entity: MME) 140, and a user plane device (UserPlane Entity: UPE). 160, Broadcast/Multicast Service Center (Broadcast Multicast Service Center: BM-SC) 180, eNB 120, MME 140 and UPE 160 are respectively connected through IP network.

The eNB 120 is responsible for allocation and management of radio resources, receives information forwarded from the physical layer of the UE 100 through the uplink, and forwards data to the UE 100 through the downlink. The eNB 120 acts as an access point between the UE 100 and the radio access network.

The MME 140 manages the location of the UE 100 in units of a location registration area (Tracking Area: TA), and performs signaling related to RAB setting, correction, and release with the UE 100. The MME 140 holds the context (context) related to the MBMS of the UE 100 allocated in the network connection procedure of the UE 100. There are multiple MMEs 140 in a certain MBMS area, and each user is connected to a different MME.

UPE 160 functions as a gateway with an external network, forwards downlink packets to the eNB connected to UE 100 according to RAB settings, and forwards uplink packets to an appropriate external network according to the destination address of the packets. Only one UPE 160 exists for one MBMS in a certain MBMS area, and holds the context related to the MBMS.

The BM-SC 180 is located between the MBMS content server and the UPE 160, and forwards information about session types, start and end of services or MBMS data to the UPE 160.

FIG. 4 is a block diagram showing the structure of the MME 140 shown in FIG. 3 . In FIG. 4, the input unit 141 notifies the user information management unit 142 of signals input from the BM-SC 180, the UPE 160, and the eNB 120.

The user information management unit 142 compares the MBMS receiving capability of the UE 100 with the capability of the UE 100 required by the service included in the MBMS registration response notified from the BM-SC 180. As a result of this comparison, if the MBMS reception performance of the UE 100 is higher than the performance of the UE 100 required by the service, the user number counting unit 143 is notified of the service and the identifier of the location registration area to which the UE 100 belongs. In addition, if the MBMS reception performance of UE 100 is lower than the performance of UE 100 required by the service, BM-SC 180 and UE 100 are notified of the suspension of processing.

The number of users counting unit 143 counts the number of users participating in each service in units of location registration areas, and updates the number of users based on the services and location registration area identifiers notified from the user information management unit 142 . The updated number of users is output to the output unit 144 . In this way, the MME 140 can utilize the UE's location registration to count the number of users.

The output unit 144 includes the number of users output from the number of users counting unit 143 in the MBMS registration update, and transmits the MBMS registration update to the UPE 160.

FIG. 5 is a block diagram showing the structure of the UPE 160 shown in FIG. 3. In FIG. 5, input unit 161 notifies signal input from BM-SC 180, MME 140, and eNB 120 to parameter unit 162 and user count unit 163. Specifically, the input unit 161 notifies the user number counting unit 163 of the number of MBMS users of each service in the location registration area unit included in the MBMS registration update.

The parameter unit 162 manages various parameters about the data path, and outputs the business data input from the BM-SC 180 from the output unit 165 according to the setting of the parameters.

The number of users counting unit 163 counts the number of users participating in each service in units of location registration areas. Since a plurality of MMEs 140 exist in the MBMS area, the number of users managed by the UPE 160 is the total value of the number of users notified from each MME. Therefore, UPE 160 can grasp the number of users participating in the service existing in the MBMS area in units of location registration areas. The user number counting unit 163 that receives the MBMS registration update updates the number of users participating in the service, and outputs the updated number of users to the user number comparing unit 164 .

User number comparing section 164 compares the number of users output from user number counting section 163 with a preset threshold value for each location registration area. As a result of the comparison, when the number of users is greater than the threshold, MCT is selected as the forwarding mode of the location registration area, and when it is less than the threshold, SCT is selected. The identifier indicating the selected MCT or SCT is output to output unit 165 .

The output unit 165 serving as a notification means outputs the traffic data output from the parameter unit 162 and the identifier indicating the MCT or SCT output from the user number comparison unit 164 to the eNB 120.

In the following, the procedure for a user to join a multicast join group will be described. Fig. 6 is a sequence diagram showing a procedure for joining a multicast joining group.

In step (hereinafter abbreviated as "ST") 201, the UE 100 that has received the service notification transmits a multicast join request to the MME 140. The multicast join request includes the identifier of the multicast group to be joined.

In ST202, the user approval procedure is performed between MME 140 and BM-SC 180 that have received the multicast join request. This verification step is performed based on the user's joining contract information, and it is judged whether the user can really accept the service.

When the approval procedure is successfully completed, MME 140 transmits an MBMS context activation request to UE 100 in ST203.

In ST204, the UE 100 that has received the MBMS context activation request transmits the MBMS context activation request to the MME 140. The MBMS context activation requirements include UE 100's own capabilities for receiving MBMS, and the like.

The MME 140 that has received the MBMS context activation request transmits the MBMS registration request to the BM-SC 180 in ST205 when the UE 100 is the first participant of the multicast group of the service. When the UE 100 is not the first participant of the multicast group of the service, the processing of ST205 and ST206 is not performed. The identifier of the UPE 160 used to broadcast MBMS data is included in the MBMS registration request.

In ST206, the BM-SC 180 that has received the MBMS registration request sends the MBMS registration response including the UE 100's capabilities required by the service to the MME 140.

In ST207, the MME 140 counts the number of users participating in each service in units of location registration areas, and updates the number of MME users. In ST208, the MME 140 transmits the MBMS Registration Update to the UPE 160. The MBMS registration update includes the updated number of MBMS users with the location registration area as a unit.

In ST209, UPE 160 counts the number of users participating in the service existing in the MBMS area in units of location registration areas, and updates the number of UPE users. In ST210, MME 140 notifies UE that MBMS context activation is accepted.

Through the above processing, the joining step of the user joining the multicast joining group is completed. In addition, the update of the number of MME users is also updated when the user leaves the multicast group and when the location registration area of UE 100 is updated, and the update result is notified to UPE 160, and the UPE user number is also updated in UPE 160 .

Next, the session start procedure will be described using FIG. 7 . After detecting the start of a certain MBMS service, in ST301, the BM-SC 180 transmits a session start request to the UPE 160.

In ST302, the user number comparison unit 164 of the UPE 160 that has received the session start request compares the number of users participating in the service existing in the MBMS area with a preset threshold for each location registration area. When the number of participating users is greater than or equal to the threshold, MCT is selected as the forwarding mode of the location registration area, and when it is less than the threshold, SCT is selected.

When MCT is selected, that is, when there are many users in each location registration area, in ST303 and ST304, through the output unit 165, the service notification is notified to eNB 120 and UE100, and any UE 100 in the location registration area All locations are able to accept business, and no follow-up processing is required.

On the other hand, when SCT is selected in user number comparing section 164, that is, when there are only a few users in each location registration area, in order to broadcast MBMS data only to eNB 120 where users exist, in ST303 and ST304, perform The step of confirming the existence of the UE in the whole location registration area, that is, counting.

In addition, the session start request in ST303 includes an identifier indicating MCT or SCT, and the eNB 120 receiving the session start request determines whether to perform service notification or count based on this. In addition, the Notification/Counting notification in ST304 also includes information indicating whether to perform counting, and UE 100 judges whether to respond to counting based on this.

After UE 100 receives the information of counting the service from the service notification related to MBMS, in order to notify eNB 120 that it wants to receive the MBMS, UE 100 sets up an RRC connection to eNB 120 in ST305. Here, the fact that UE 100 desires to receive the MBMS is notified to eNB 120 by using the RRC connection request message.

By identifying the UE that forwarded the RRC connection request message, eNB 120 recognizes that there is a user requesting a specific MBMS in the cell, and establishes an MBMS radio bearer in ST306 even if there is only one user.

In ST307, eNB 120 transmits a request to join a multicast group to UPE 160 in order to form an IP multicast tree on the IP network between eNB 120 and UPE 160.

Each IP router and UPE 160 that receives the multicast group participation request stores the output interface where the user participating in the service is located, and only forwards the MBMS data to the required output interface later.

Through the above processing, a series of session initiation steps are completed, and the MBMS data output from BM-SC 180 is transmitted to UPE 160, and from UPE 160 is transmitted only to eNB 120 of MBMS existing users, and finally transmitted to UEs participating in the multicast group 100.

Next, maintenance of the distribution route of MBMS data set in the above-mentioned session start procedure will be described. The RRC connection between UE 100 and eNB 120 established in ST305 of the session start step is limited to a control plane that only transmits and receives control signals.

Limiting the RRC connection to the control plane means that only the control plane is active, that is, it only has radio link control (Radio Link Control: RLC) and media access control (Media Access Control) for sending and receiving RRC messages. : MAC)-related entities, and does not perform the state of channel quality reporting (CQI reporting) required for transmission and reception of user plane data by UE 100 and monitoring of downlink common control channels at all.

Therefore, as long as the UE 100 does not move, the UE 100 does not transmit or receive signals at all except for receiving MBMS-related control signals and service data, so that battery consumption can be kept low. Furthermore, by discontinuously receiving (DRX) MBMS data at intervals suitable for the MBMS, it is possible to keep battery consumption even lower.

In addition, only the state where the control plane is active is limited between the eNB 120 and the UE 100, and no information is provided to the MME 140 that manages the location of the UE 100, so the MME 140 continues to manage the location of the UE 100 in units of location registration areas .

Since the eNB 120 maintains the RRC connection with the UE 100, it can manage the location of the UE 100 in units of cells. Therefore, when UE 100 moves to another adjacent eNB, a normal handover procedure is performed to transfer the RRC connection with UE 100 to the eNB of the moving destination. As a result, the destination eNB detects that the MBMS user has moved to its subordinate, and if the service is not provided, it outputs a multicast group participation request to provide a new service. Also, if there are no other UEs 100 participating in the multicast group, the source eNB notifies the UE 160 of leaving the multicast group.

Generally speaking, the UE 100 in the active state measures the reception quality of neighboring cells, and notifies the eNB 120 of the result periodically or every event.

Here, it is assumed that UE 100 is located near the border of adjacent cells. The eNB 120, having received the measurement result of the reception quality of the neighboring cell reported from the UE 100, detects that the UE 100 is located near the boundary of a certain neighboring cell.

In general, in SCT, the reception quality of users located at the edge of a cell deteriorates. Therefore, when the user is located at the edge of the cell, the mode is switched from SCT to MCT to perform inter-cell diversity integration.

FIG. 8 is a sequence diagram showing a mode switching procedure from SCT to MCT, and FIG. 9 is a block diagram showing the configuration of eNB 120 according to Embodiment 1 of the present invention. In FIG. 8 , in ST401, UE 100 measures the reception quality of surrounding cells according to preset conditions, and notifies the measurement result to the s-eNB (eNB of the moving source).

In ST402, the s-eNB having received the measurement result detects that UE 100 exists on the border with a certain neighboring cell based on the measurement result, and in ST403, transmits a request to join the multicast group to the t-eNB (moving destination local eNB).

In ST404, the t-eNB that has received the multicast group participation request transmits the multicast group participation request to the UPE 160 through the output unit 125 when it has resources to participate in the MBMS. The identifier of the s-eNB and information indicating switching to the MCT are included in the multicast group participation request.

In ST405, the UPE 160 that receives the multicast group participation request switches the forwarding mode from SCT to MCT, and in ST406, performs scheduling so that s-eNB and t-eNB can output data synchronously, and the scheduling results are respectively Notify s-eNB and t-eNB.

The parameter unit 122 of the s-eNB and t-eNB that received the scheduling result stores the notified scheduling information and notifies it to the output unit 125 . The output units 125 of the s-eNB and t-eNB transmit MBMS data at predetermined timings, and the UE 100 receives the combined signals from multiple cells, thereby improving the reception quality.

Here, the configuration of the eNB 120 described above will be described. In FIG. 9, the input unit 121 notifies the parameter unit 122, the cell edge detection unit 123, and the multicast processing unit 124 of signals input from the UE 100, the MME 140, the UPE 160, and the eNB 120.

The parameter unit 122 manages various parameters set by signaling with the UE 100, MME 140, UPE 160, and eNB 120, and outputs MBMS data from the output unit 125 as a forwarding part according to the parameters specified by the parameter unit 122.

The cell edge detection unit 123 of the s-eNB that has received the measurement result detects that the UE 100 is located at the boundary of a certain adjacent cell, and outputs the identifier of the adjacent cell to the multicast processing unit 124.

The multicast processing unit 124, when the device is an s-eNB, based on the identifier of the adjacent cell output from the cell edge detection unit 123, sends the request for joining the multicast group to the management of the adjacent cell through the output unit 125. t-eNB.

In addition, the multicast processing unit 124 receives a multicast group participation request when the device is a t-eNB, and transmits the multicast group participation request to the UPE 160 through the output unit 125 if there are resources to participate in the MBMS.

In this way, according to Embodiment 1, the number of UEs that have performed location registration is counted for each location registration area including a plurality of cells, and if the counted number of UEs is greater than or equal to a predetermined threshold, MCT is selected, and if the counted number of UEs is less than If the predetermined threshold is set, SCT is selected, so that SCT and MCT can be appropriately switched according to the number of UEs, so it is possible to reduce redundant data broadcasting caused by MCT, and reduce redundant counting caused by SCT, thereby reducing battery consumption .

In addition, in this embodiment, the UPE 160 compares the number of users participating in the service existing in the MBMS area with a preset threshold for each location registration area. In the same way, the number of users is compared by a specific selected MME.

In addition, in this embodiment, it is detected from the reception quality measurement result from UE 100 that UE 100 is located at the boundary of a certain neighboring cell, but NACK may also be used, and eNB 120 requests the neighboring cell to participate in the multicast when receiving NACK. The NACK is used to urge the eNB 120 to retransmit the transmitted incomplete data when the reception quality of the UE 100 is degraded.

In addition, in this embodiment, the user number comparison process in ST302 shown in FIG. 7 is performed using the number of UEs in units of location registration areas, but the comparison may be performed in units of multiple location registration areas.

(Embodiment 2)

In Embodiment 2 of the present invention, a case will be described in which UE 100 transitions to the idle state again after selecting the SCT and counting.

Since the movement of the UE 100 in the idle state cannot be determined on the network, recounting (recounting: equivalent to counting) is performed periodically, and it is judged whether to maintain or delete the MBMS radio bearer in units of cells.

In general, when counting, the response messages of the MBMS UE are required to be concentrated on the uplink channel at the same time, which increases the interference and load on the uplink, so the response probability (Probability Factor: PF) is set. Only UEs that have generated random numbers equal to or less than the PF value transmit RRC response messages, thereby avoiding simultaneous responses.

FIG. 10 is a flowchart showing the recounting procedure in eNB 130 according to Embodiment 2 of the present invention. Furthermore, FIG. 11 is a block diagram showing the configuration of eNB 130 according to Embodiment 2 of the present invention. Hereinafter, the recounting procedure will be described using these figures.

The eNB 130 notifies the cumulative count comparison unit 131 of the input signal from the UE 100 through the input unit 121 as an acquisition means.

In ST501, the parameter selection unit 132 sets the initial PF value (parameter) when starting the recounting step, and in ST502, the selected initial PF value is sent to the UE through the output unit 125 through Notification/Counting notification 100. In addition, the UE 100 that has received the PF value compares the random number generated by itself with the received PF value, sends a response message when the random number is below the PF value, and waits until the random number is greater than the PF value. Until the next PF value is received.

In ST503, the input unit 121 of the eNB 130 receives the response message from the UE 100, and notifies the accumulated count comparison unit 131 of the received response message.

In ST504, the accumulative count comparison unit 131 as a counting means cumulatively counts the number of received response messages, and in ST505, compares whether the accumulated count value is equal to or greater than a preset threshold. When the accumulated count value is equal to or greater than the threshold ("YES"), the process goes to ST508, and when the accumulated count value is smaller than the threshold ("No"), the process moves to ST506.

In ST506, it is judged by the accumulative count comparing means 131 whether or not the number of trials in ST502 to ST505 has reached a preset number (predetermined value). When the number of trials reaches the predetermined value ("YES"), the process moves to ST509, and when the number of trials does not reach the predetermined value ("No"), the process moves to ST507.

In ST507, since the number of trials has not reached the predetermined value, a PF value whose value is greater than the PF value used this time is selected by the parameter selection unit 132 . Since a larger PF value than this time is selected in the next trial, it is expected that the number of UEs 100 that transmit the response message will be large. After several trials, when the cumulative count value is greater than or equal to the threshold value in the determination of ST505, the cumulative count comparison unit 131 notifies the recount period selection unit 133 to select the recount period, and notifies the parameter selection unit 132 to select the next initial PF value. .

In ST508, since the eNB 130 grasps that there are a large number of MBMS users in the subordinate cells, in a cell with a large number of users, the probability that a certain user will continue to stay in the cell is high, so the recounting cycle selection unit 133 Set the recount period longer. Thereby, the battery consumption of UE 100 can be reduced. In addition, for the next recount, the initial PF value is set smaller by parameter selection section 132 . Thereby, uplink congestion can be avoided.

When it is determined in ST506 that the number of trials has reached the predetermined value, in ST509 cumulative count comparison section 131 notifies recount period selection section 133 to select a recount period, and notifies parameter selection section 132 to select the next first PF value. Since the eNB 130 grasps that there are only a small number of MBMS users in its subordinate cells, all users may leave the cell in a cell with a small number of users, so the recounting period selection unit 133 sets a shorter recounting period period (the default). In this way, it is possible to quickly detect that the number of users in the cell becomes zero, and by stopping broadcasting of MBMS data to the cell, the utilization efficiency of radio resources of the entire network can be improved. In addition, parameter selection section 132 sets a larger initial PF value because the probability of uplink congestion in the next recount is low. Thereby, the time required for recounting to be completed can be reduced.

As described above, according to Embodiment 2, when it is determined that the number of users in the cell is large based on the recounting performed by the SCT, the battery consumption of the UE is reduced by setting the recounting period longer, and by setting the initial PF The value is set smaller to reduce the interference and load on the uplink caused by simultaneous response. On the other hand, when it is judged that the number of users in the cell is small, the situation that the number of users in the cell becomes zero is quickly detected by setting the recounting period short, and if the broadcasting of MBMS data to the cell is stopped, the improvement can be improved. The utilization efficiency of the radio resources of the entire network can be reduced by setting the initial PF value large to reduce the time required for recounting to be completed.

In addition, in this embodiment, the number of users in the cell is divided into two cases, which are more or less. However, the present invention is not limited thereto. Recount period and PF value.

(Embodiment 3)

In Embodiment 3 of the present invention, a case will be described in which the forwarding mode is selected again according to the distribution of eNB 120 where MBMS users exist after the SCT is selected and counted.

FIG. 12 is a block diagram showing the structure of UPE 170 according to Embodiment 3 of the present invention. However, parts in FIG. 12 that are common to those in FIG. 5 are assigned the same reference numerals as in FIG. 5 , and detailed description thereof will be omitted.

In FIG. 12, input unit 171 notifies signal input from BM-SC 180, MME 140 and eNB 120 to parameter unit 162, user count unit 163 and eNB distribution determination unit 172. Specifically, the input unit 171 notifies the user number counting unit 163 of the number of MBMS users of each service in the location registration area unit included in the MBMS registration update. Furthermore, the eNB distribution determination unit 172 is notified of the eNB identifier of the eNB 120 indicating that the MBMS user exists included in the multicast group participation request.

The eNB distribution determination unit 172 determines the distribution of eNBs 120 where MBMS users exist, that is, the distribution to the entire location registration area, based on the eNB identifier output from the input unit 171. As a result of the determination, when the distribution of eNB 120 with MBMS users satisfies the preset condition, MCT is selected as the forwarding mode in the location registration area, and when the condition is not satisfied, SCT is continued to be selected. The identifier indicating the selected MCT or SCT is output to output unit 173 .

The output unit 173 serving as a notification means outputs the traffic data output from the parameter unit 162, the identifier indicating the MCT or SCT output from the user number comparing unit 164, and the identifier indicating the MCT or SCT output from the eNB distribution determining unit 172. to eNB 120.

Next, the procedure for starting a session according to Embodiment 3 of the present invention will be described using FIG. 13 . However, parts in FIG. 13 that are common to those in FIG. 7 are assigned the same reference numerals as in FIG. 7, and detailed description thereof will be omitted.

In FIG. 13 , in ST601, eNB 120 transmits a request to join a multicast group to UPE 170 in order to form an IP multicast tree on the IP network between eNB 120 and UPE 170. In this case, the eNB 120 includes an identifier indicating itself as the eNB identifier in the multicast group joining request.

Each IP router that has received the multicast group participation request stores the output interface where the user participating in the service is located.

In ST602, the UPE 170 that has received the multicast group participation request temporarily stores the eNB identifier included in the multicast group participation request in the eNB distribution determination unit 172, and by this count, the number of existing MBMS users All eNBs 120 obtain the multicast group participation requirement. Here, eNB distribution determination unit 172 calculates the ratio of the number of eNBs in which MBMS users exist to the total number of eNBs in the entire location registration area. When the ratio is equal to or greater than a predetermined threshold, MCT is selected as the forwarding mode in the location registration area, and when it is smaller than the threshold, SCT is selected.

When MCT is selected, transfer to ST603, and when SCT is selected, UPE 170 stores the output interface where the user participating in the service is located. When SCT continues to be selected, through the above processing, a series of session start steps are completed, and the MBMS data output from BM-SC 180 is transmitted to UPE 170, and from UPE 170 is only transmitted to eNB 120 where MBMS users exist, and finally sent to to the UE 100 participating in the multicast group.

The UPE 170 has notified the eNB 120 of the fact that the SCT is selected in ST303. Then, in ST603, UPE 170 transmits a forwarding mode change notification indicating switching from SCT to MCT to all eNBs 120 within the location registration area.

In addition, the forwarding mode change notification in ST603 also includes the identifier indicating the MCT or SCT and information indicating whether to count, and the eNB 120 receiving the forwarding mode change notification judges whether to change the forwarding mode based on this, and judges whether the Counting is performed periodically after reception.

Through the above processing, a series of session start steps are completed. In each location registration area, there are only a small number of users, but a small number of MBMS users are distributed in the location registration area without omission. Since the MCT is finally selected, the UE 100 Any location within the registered area of the location is able to accept business.

In addition, as described in Embodiment 1, when the number of users per location registration area is equal to or greater than the threshold and MCT is selected, no counting is required, but if the number of users per location registration area is less than the threshold and is small When MBMS users are distributed in the location registration area without exception and MCT is selected, the ratio of the number of eNBs with MBMS users to the total number of eNBs in the entire location registration area changes due to the movement of UE 100. to count. That is, the processing from ST304 to ST601 shown in FIG. 13 is performed periodically. Thus, the UPE 170 performs the eNB distribution determination process of ST608 every time it counts, and selects the forwarding mode based on the result.

In this way, according to Embodiment 3, when the number of users per location registration area is smaller than the threshold but a small number of MBMS users are distributed in the location registration area without exception, by switching the forwarding mode from SCT to MCT, it is possible to reduce the number of MBMS users associated with each location registration area. The amount of signaling between the eNBs and between the eNB and the core network device involved in switching the forwarding mode from the SCT to the MCT, without reducing the utilization efficiency of radio resources.

In addition, in this embodiment, the eNB distribution determination unit 172 switches the forwarding mode based on the ratio of the number of eNBs with MBMS users to the total number of eNBs in the entire location registration area. According to the configuration information of the eNB 120, the distribution status of the eNB 120 that actually has MBMS users is judged from the notified eNB identifier, so as to switch the forwarding mode.

In addition, in this embodiment, the eNB distribution determination unit 172 switches the forwarding mode based on the distribution of eNBs 120 with MBMS users at the time of counting. distribution to switch forwarding modes.

(Embodiment 4)

In Embodiment 4 of the present invention, an operation performed at the cell edge of a cell located at the boundary of the location registration area in which the MCT is selected will be described.

At the cell edge of a cell located at the boundary of the location registration area where the MCT is selected, eNB 120 located at the boundary of the adjacent location registration area (e.g., eNB3 and eNB5 in the case of FIG. 3 ) does not provide services. In this case, inter-cell diversity integration cannot be performed, and service reception quality may be degraded. Therefore, in this embodiment, the eNB 120 located at the boundary of the location registration area regularly inquires about the MBMS provision status to the N-eNB1 to n located at the boundary of the adjacent location registration area.

FIG. 14 is a sequence diagram of querying the MBMS provision status between eNBs 120 located at the boundaries of different location registration areas. In the multicast processing unit 124 of the eNB 120 located at the boundary of the location registration area, the fact that it is located at the boundary of the location registration area is preset.

In FIG. 14, in ST701, in the case of providing MBMS in the MCT mode, the multicast processing unit 124 of the eNB 120 outputs a service query through the output unit 125, so as to send to the N-eNB1 located at the border of the adjacent location registration area ~n Query the status of MBMS provision. In addition, a service identifier indicating the MBMS is included in the service query.

In ST702, the input unit 121 of the N-eNB 1-n that has received the service query outputs the service identifier to the multicast processing unit 124. The multicast processing unit 124 judges the provision status of the service indicated by the service identifier, includes the result in the service response, and outputs it to the eNB 120 that has performed the service query through the output unit 125.

In ST703, the input unit 121 of the eNB 120 that has received the service response outputs the MBMS provision status of N-eNB 1 to n included in the service response to the multicast processing unit 124. The multicast processing unit 124 determines the N-eNBs 1-n that need to participate in the MBMS according to the MBMS provision status of the N-eNBs 1-n. Here, the N-eNBs 1 to n that need to participate in the MBMS refer to the N-eNBs 1 to n that do not provide the MBMS and are adjacent to a cell in which a user requesting the MBMS exists in an adjacent location registration area.

The N-eNBs 1 to n that need to participate in the MBMS and the eNB 120 that specifies the N-eNBs 1 to n complete the participation in the MBMS by performing the processes after ST403 shown in FIG. 8 .

In this way, according to Embodiment 4, eNB 120 located at the boundary of a location registration area periodically inquires about the MBMS provision status to N-eNBs 1~n located at the boundary of adjacent location registration areas, and makes N-eNBs that do not provide the MBMS 1 to n participate in the multicast group, thereby reducing the degradation of service reception quality at the cell edge of the cell located at the boundary of the location registration area where the MCT is selected.

In addition, in this embodiment, the necessity of participating in the MBMS of N-eNB 1 to n is judged by regularly inquiring about the MBMS provision status to N-eNB 1 to n located at the boundary of adjacent location registration areas, but it is also possible to All the MBMS users located in the cell at the border of the location registration area where the MCT is selected are switched to the active state, and cell edge detection is performed in the same manner as in Embodiment 2, so that N-eNBs 1 to n participate in the MBMS.

(Embodiment 5)

In Embodiment 5 of the present invention, the timing at which UE 100 in an active state transmits a measurement report (Measurement Report) in a cell in which an SCT is selected will be described.

The UE 100 in the active state in the cell for which the SCT is selected measures the reception quality of the neighboring cell, and notifies the eNB 200 of the measurement result periodically or every event. Hereinafter, the notification of the reception quality measurement result is referred to as "Measurement Report". Thus, the eNB 200 judges which edge of the cell the UE 100 is located in, and requests the corresponding neighboring cell to participate in the MCT mode.

Here, regardless of the reception result of the MBMS data, that is, whether the MBMS data is received normally, the measurement report is transmitted periodically or every event. Therefore, although the MBMS data can be received normally, the UE 100 may still transmit unnecessary measurement reports, thereby wasting battery. Conversely, although a defect in MBMS data is detected, it may take some time until the transmission timing of the measurement report, and the reception quality may continue to be poor.

Therefore, in this embodiment, when the UE 100 existing at the edge of the cell detects a data defect in MBMS, the UE 100 sends the measurement report of the neighboring cell to the eNB 200 at the opportunity of sending a NACK requesting retransmission of the defective data. .

FIG. 15 is a block diagram showing the configuration of UE 100 according to Embodiment 5 of the present invention. In FIG. 15 , input unit 101 inputs MBMS data packets received from eNB 200 to received data determination unit 102, and outputs reference signals received from adjacent cells to received power measurement unit 103.

Received data judging section 102 judges whether or not the MBMS data packet output from input section 101 has been received normally. When it can be received normally, the received packet is forwarded to the upper layer. When it cannot be received normally, that is, when a defect of the received data packet is detected, a NACK message for requesting retransmission of the defective data is generated, and the generated NACK message is sent to the eNB 200 through the output unit 104, and the received power is requested. The measurement unit 103 transmits a measurement report.

The received power measuring section 103 measures the received power of each adjacent cell using the reference signal output from the input section 101, and based on the request from the received data determining section 102, combines the identifier of the adjacent cell and the result of the measurement including the received power. The measurement report is sent to eNB200 through output unit 104 .

FIG. 16 is a block diagram showing the configuration of eNB 200 according to Embodiment 5 of the present invention. However, the parts in FIG. 16 that are common to those in FIG. 9 are given the same reference numerals as those in FIG. 9, and detailed description thereof will be omitted.

In FIG. 16 , input unit 201 stores MBMS data packets received from UPE 160 in buffer unit 202. Also, upon receiving NACK requesting retransmission of the defective MBMS data and a measurement report from UE 100 , the measurement report is output to cell edge detection section 203 . When the retransmission of the missing MBMS data packet is requested by the cumulative count comparison unit 204, the MBMS data packet stored in the buffer unit 202 is retransmitted to the UE 100 through the output unit 125.

Based on the measurement report input from the input unit 201, the cell edge detection unit 203 detects which adjacent cell the UE 100 that has transmitted the measurement report is located at the edge of, and notifies the identifier of the detected adjacent cell to the cumulative count comparison Unit 204.

Cumulative count comparison section 204 compares the number of all users located at the cell edge with a preset threshold for each adjacent cell notified from cell edge detection section 203 . As a result of the comparison, if the number of users is above the threshold, the identifier of the adjacent cell is notified to the multicast processing unit 124, and if it is lower than the threshold, the input unit 201 is requested to retransmit the stored data in the buffer unit 202. The MBMS data packet corresponding to the NACK among the MBMS data packets.

In addition, the operation after cumulative count comparison section 204 notifies multicast processing section 124 of the identifier of the adjacent cell is the same as the operation after ST403 in FIG. 8 , and thus description thereof will be omitted.

As described above, according to Embodiment 5, when the UE 100 located at the edge of the cell detects a defect in the MBMS data packet, the UE 100 sends a measurement report of the neighboring cell by sending a NACK requesting retransmission of the defective data as an opportunity. This transmits the measurement report to the NB 200 only when necessary, so that the battery consumption of the UE 100 can be kept low. In addition, when there are many users near the edge of the cell, by switching from the SCT to the MCT, it is possible to efficiently improve the user's received service quality.

Also, in this embodiment, a case has been described in which NACK and measurement report for requesting retransmission of the defective MBMS data packet are transmitted separately, but NACK and measurement report may be transmitted as one message.

(Embodiment 6)

In Embodiment 6 of the present invention, a method for efficiently counting the number of users located near the cell edge of a specific adjacent cell will be described.

In Embodiment 5, the number of all users located near the cell edge is compared with a preset threshold for each adjacent cell, and if the number of users exceeds the threshold, a handover to MCT is requested for the adjacent cell. However, since there are cell edges corresponding to the number of adjacent cells, it takes time until the number of users located near the cell edge of a specific adjacent cell reaches a threshold from all users located near the cell edges. , so that inefficient retransmissions may be repeatedly performed. Therefore, in this embodiment, transmission of measurement reports is limited to users located near the cell edge of a specific neighboring cell.

Hereinafter, the transmission method of the measurement report in this embodiment is demonstrated using FIG.15 and FIG.16.

In the eNB 200 shown in FIG. 16 , the parameter selection unit 132 selects a cell identifier of a neighboring cell at each preset period, and sends the selected cell identifier to the UE 100 through the output unit 125. The cell identifier is used to designate a UE that transmits a measurement report among UEs that are located near the edge of the cell and detect a defect in the MBMS data packet.

In UE 100 shown in FIG. 15 , input section 101 notifies received power measurement section 103 of the cell identifier received from eNB 200. The received data judging section 102 having detected a defect in the MBMS data packet requests the received power measuring section 103 to transmit a measurement report.

Received power measurement section 103 determines whether or not the transmitted measurement report includes information on the neighboring cell corresponding to the cell identifier notified from input section 101 . When the information of the neighboring cell is included, the measurement report is transmitted to the eNB 200, and when the information of the neighboring cell is not included, the transmission of the measurement report is stopped. Since the subsequent threshold determination and switching to MCT operations in the eNB 200 are the same as those in Embodiment 5, detailed description thereof will be omitted.

In this way, according to Embodiment 6, among the UEs located near the cell edge and detecting the defect of MBMS data packets, only UEs located near the cell edge of a specific neighboring cell are allowed to transmit measurement reports, thereby efficiently counting the UEs located near the cell edge of a specific adjacent cell. The number of users at the cell edge of the adjacent cell can be quickly switched from SCT to MCT for the adjacent cell.

In addition, in the present embodiment, parameter selection section 132 selects the cell identifiers of neighboring cells every predetermined period, but may continuously select only the cell identifiers adjacent to the edge of a cell estimated in advance to have poor reception quality. The identifier of the cell.

In addition, in this embodiment, only users located near the cell edge of a specific neighboring cell are allowed to transmit measurement reports among users who have detected MBMS data packet defects, but it is also possible to combine the PF to control, so as not to send a large number of measurement reports at the same time.

In addition, in the above-mentioned embodiments, the case where the present invention is configured by hardware has been described as an example, but the present invention can be realized by software.

In addition, each functional block used in the description of each of the above-mentioned embodiments is typically realized as an LSI of an integrated circuit. These blocks may be individually integrated into one chip, or part or all of them may be integrated into one chip. Although it is called LSI here, it can also be called IC, system LSI, super LSI (Super LSI), or ultra LSI (Ultra LSI) depending on the degree of integration.

In addition, the technique of circuit integration is not limited to LSI, and it can also be implemented using a dedicated circuit or a general-purpose processor. It is also possible to use a programmable FPGA (Field Programmable Gate Array: Field Programmable Gate Array) after the LSI is manufactured, or a reconfigurable processor that can reconfigure the connection and settings of the circuit cells inside the LSI.

Furthermore, if there is an integrated circuit technology that replaces LSI with the advancement of semiconductor technology or the derivation of other technologies, of course this technology can also be used to realize the integration of functional blocks. There is also the possibility of applying biotechnology and the like.

Japanese Patent Application No. 2006-229811 filed on August 25, 2006, Japanese Patent Application No. 2006-274080 filed on October 5, 2006, and Japanese Patent Application No. 2006-2006 filed on November 16, 2006 The disclosures of the specification, drawings and abstract contained in 310271 are hereby incorporated by reference in this application.

Industrial Applicability

The core network device, wireless communication base station device and wireless communication method of the present invention can improve the utilization efficiency of wireless resources of the entire network without increasing battery consumption of the UE, and can be applied to a transmission control system providing MBMS.

Claims (13)

1. Core network devices, including: The number of users counting unit, taking the location registration area as a unit, counts the number of users participating in the multimedia broadcast/multicast service (MBMS); The user number comparison unit compares the counted number of users with a predetermined threshold, selects multi-cell forwarding when the number of users is greater than the threshold, and selects multi-cell forwarding when the number of users is smaller than the threshold single-cell forwarding, the multi-cell forwarding is a forwarding in which a plurality of wireless communication base station apparatuses belonging to the same frequency area synchronously forward MBMS data, and the single-cell forwarding is a single cell including users participating in the MBMS The forwarding of the wireless communication base station device forwarding the MBMS data; and The notification unit notifies the selected multi-cell forwarding or single-cell forwarding to the subordinate wireless communication base station apparatus. 2. The core network device according to claim 1, further comprising: a distribution determination unit, when the user number comparison unit selects single-cell forwarding, based on the distribution status of the wireless communication base station devices that are the target of single-cell forwarding, Select the forwarding mode. 3. The core network device according to claim 2, wherein when the ratio of the number of wireless communication base station devices to be forwarded by a single cell to the total number of wireless communication base station devices per location registration area is equal to or greater than a predetermined threshold, said The distribution determination unit selects multi-cell forwarding. 4. Wireless communication base station devices, including: The acquiring unit is configured to acquire, from the core network device, an indication of multi-cell forwarding or a single-cell forwarding indication, the multi-cell forwarding is that multiple wireless communication base station devices belonging to the same frequency area synchronously forward multimedia broadcast/multicast services (MBMS) The forwarding of data, the forwarding of the single cell is the forwarding of MBMS data forwarded by a single wireless communication base station device including users who have participated in MBMS in the cell; A counting unit, which counts in the cells managed by the device only when the instruction forwarded by a single cell is obtained; and The forwarding unit forwards the MBMS data in the cell where the user exists as a result of the counting. 5. The wireless communication base station device according to claim 4, when the instruction of single-cell forwarding is obtained, the counting unit makes the wireless communication terminal devices in the cell managed by the device only transfer the control channel to the active mode, so as to Cell counts the number of users in units. 6. The wireless communication base station device according to claim 4, further comprising: a detection unit that acquires a reception quality measurement result of surrounding cells measured by the wireless communication terminal device, and detects a wireless communication terminal device existing on the edge of the cell based on the obtained reception quality measurement result; and The multicast processing unit, when detecting a wireless communication terminal device on a cell edge, issues an MBMS join request to an adjacent cell forming the cell edge. 7. The wireless communication base station device according to claim 4, further comprising: A recounting period selection unit selects the interval until the next count, that is, the recounting period; and A parameter selection unit selects a response probability as a condition for requesting a wireless communication terminal device of MBMS to transmit a response message, When the instruction of single-cell forwarding is obtained, the counting unit controls the recounting period selection unit and the parameter selection unit so that when the number of users in the cell is above a predetermined threshold, the recounting period is extended and the response is reduced. probability, and when the number of users in the cell is less than the specified threshold, the recounting period is shortened and the response probability is increased. 8. The wireless communication base station device according to claim 4, further comprising: a multicast processing unit that inquires about the MBMS provision status of other wireless communication base station devices located at the border of adjacent location registration areas, and sends MBMS provision status to all wireless communication base station devices that do not provide MBMS The above-mentioned other wireless communication base station device makes an MBMS join request. 9. The wireless communication base station device according to claim 4, further comprising: The detection unit is configured to detect a wireless network existing on the edge of the cell based on the obtained reception quality measurement result when NACK of the MBMS data requiring retransmission of the defective MBMS data and the reception quality measurement result of the adjacent cell measured by the wireless communication terminal device are obtained. communication terminal device; a counting unit, counting the number of users existing on the edge of the cell detected by the detection unit for each adjacent cell; The multicast processing unit, when the number of users counted for each neighboring cell is equal to or greater than a predetermined threshold, sends an MBMS join request to the neighboring cell; and The retransmitting unit retransmits the MBMS data requested by the NACK when the number of users counted for each adjacent cell is smaller than a predetermined threshold. 10. The wireless communication base station apparatus according to claim 9, wherein said counting unit counts the number of users existing on a cell edge of a specific adjacent cell. 11. Wireless communication terminal devices, including: The data determination unit determines whether the received MBMS data has a defect, and when it is determined that the MBMS data has a defect, generates a NACK message requesting to resend the defective MBMS data; a received power measuring unit for measuring the received power of each adjacent cell; and The sending unit sends the NACK message and the received power measurement result of each adjacent cell to the wireless communication base station device. 12. The wireless communication terminal device according to claim 11, wherein said received power measuring unit measures received power of a specific adjacent cell. 13. Wireless communication methods, including: In the step of counting the number of users, the core network device counts the number of users participating in the Multimedia Broadcast/Multicast Service (MBMS) with the location registration area as a unit; The step of comparing the number of users is to compare the counted number of users with a predetermined threshold, and when the number of users is above the threshold, select multi-cell forwarding, and when the number of users is less than the threshold, select single-cell forwarding, the multi-cell forwarding is a forwarding in which a plurality of wireless communication base station apparatuses belonging to the same frequency area synchronously forward MBMS data, and the single-cell forwarding is a single cell including users participating in the MBMS The wireless communication base station device forwards the forwarding of MBMS data; Notification step, notifying the selected multi-cell forwarding or single-cell forwarding to the wireless communication base station device under the core network device; In the obtaining step, the wireless communication base station device obtains the multi-cell forwarding indication or the single-cell forwarding indication from the core network device; The counting step is to count in the cells managed by the wireless communication base station device only when the single-cell forwarding instruction is obtained; and In the forwarding step, the result of the counting is to forward the MBMS data in the cell where the user exists.

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