WO2011012082A1 - Method, system and device for user equipment (ue) to read multicast control channel (mcch) - Google Patents

Abstract

Provided are a method for a base station to notify a User Equipment (UE) to read a Multicast Control Channel (MCCH), the base station, a method for the UE to read the MCCH, and the UE, which are used for ensuring that the UE receives notification information correctly, thereby the UE can read the MCCH and acquire the Multimedia Broadcast Multicast Service (MBMS) in time, the robustness of the UE receiving the MEMS is improved and the probability of the UE losing the MBMS is reduced. The provided method for the UE to read the MCCH comprises: the base station determines a new MBMS session start exists currently; the base station sends notification information for notifying the UE to read MCCH information to the UE for several times in one MCCH modification period; the UE monitors the notification information sent from the base station for several times in one MCCH modification period, and reads the MCCH information according to the monitored notification information.

Description

 Method, system and device for reading MCCH by UE This application claims to be submitted to the Chinese Patent Office on July 31, 2009, and the application number is 200910090200.X, the invention is entitled "A method, system and device for reading MCCH by UE" Priority of the Chinese Patent Application, the entire contents of which is incorporated herein by reference. Technical field

 The present invention relates to the field of communications technologies, and in particular, to a technology for a user equipment (UE, User Equipment) to obtain a multicast control channel (MCCH). Background technique

 The Multimedia Broadcast Multicast Service (MBMS) in the Long Term Evolution (LTE) system is also known as the evolved MBMS (eMBMS, evolved MBMS). The main function is to implement broadcast and LTE in the LTE system. Broadcast business. Currently, MBMS of Release 9 (R9) is mainly implemented by a hybrid cell, that is, a cell that transmits MBMS services, and also transmits a unicast service.

 The logical channels related to eMBMS include:

 (1) Broadcast Control Channel (BCCH), used for the network to broadcast system information to the terminal (UE), that is, system information is transmitted through the BCCH.

 (2) The Multicast Control Channel (MCCH) is a point-to-multipoint downlink channel used by the network to transmit MBMS-related control information to the UE. The channel can only receive MBMS. The UE of the service can be used.

 (3) Multicast Traffic Channel (MTCH) is a point-to-multipoint downlink channel used by the network to transmit MBMS service data to the UE. The channel can only be used by UEs that can receive MBMS services.

One MCCH may correspond to one or more MTCHs. The information of the MTCH is indicated by its corresponding MCCH. The network indicates the MCCH to the UE by using the BCCH, and then uses the MCCH to indicate the MTCH to the UE, so that the UE correctly receives the MBMS service carried on the MTCH.

 In the MCCH transmission mode specified in the 3G system, as shown in FIG. 1 , each small square represents information carried by the MCCH, and the information carried by the MCCH is transmitted in a manner of a modification period of the MCCH and a repetition period of the MCCH. The information carried by the MCCH is unchanged during the modification period of the MCCH, and in order to ensure reliable reception of the MCCH, the UE retransmits in the repetition period of the MCCH, and the UE can receive multiple identical information in the MCCH modification period, as long as the correct reception is performed once. The information carried by the MCCH can be correctly interpreted. The information carried by the MCCH may be different between the different modification periods of the MCCH, but may be the same. That is, when the modification period of each MCCH arrives, the network may modify the information carried by the MCCH, or may not modify the information carried by the MCCH.

 The current LTE protocol specifies a paging pattern for Frequency Division Duplex (FDD) and Time Division Duplex (TDD). Table 1 below shows the paging format of FDD, and Table 2 shows the paging of TDD. Format:

 Table 2

The paging opportunity (PO, Paging occasion) is a subframe in which a user paging may occur, and thus may also be referred to as a paging subframe. As can be seen from the two tables above, for FDD systems, all User paging can only occur in subframes #0, #4, #5, and #9. For TDD systems, paging for all users may only occur in subframes #0, #1, #5, and #6.

 The MBMS Notification (MBMS Notification) mechanism is introduced in the LTE R9, and specifically includes: as shown in FIG. 2, when there is a Session Start of the MBMS, the network sends a notification information to the UE, that is, through the Notification sub- The frame informs the UE that a new MBMS session has started. The UE reads the MCCH in the modification period of the next MCCH that receives the Notification information, and obtains the specific information of the session (Session) from the MBSFN subframe. If the UE is interested in the MBMS service, Then, according to the content of the MCCH, the corresponding MTCH is read to receive the MBMS service.

 An MBMS Radio Network Temporary Identity (M-RNTI) is defined in a Physical Downlink Control Channel (PDCCH) of the physical layer for transmitting Notification information, that is, if there is a Session Start, the network will be in FIG. The PDCCH in the Notification subframe sets the M-RNTI to notify the UE that a new MBMS service session has started. For a UE that does not currently receive the MBMS service, after receiving the notification information, the MCCH will be read in the next modification period. If the UE does not receive the notification information, it will continue to monitor the Notification subframe without reading the MCCH. For the UE that is receiving the MBMS service, the MCCH information needs to be read in each MCCH modification period, and the Notification subframe does not need to be monitored.

 However, if the UE only listens to the notification information once in an MCCH modification period, if the information is lost, the UE does not read the MCCH in the next modification period, thereby causing the UE to lose the MBMS service. Therefore, only after the UE correctly receives the notification information, it will receive the MCCH normally and know the information of the MBMS service change in time. Otherwise, the UE will lose the MBMS service. At present, how to ensure the UE's reliable reception (ie, robustness) of the notification information, thereby avoiding the UE losing the MBMS service, has not yet given a specific solution. Summary of the invention

The embodiment of the present invention provides a method for a base station to notify a user equipment to read MCCH information of a multicast control channel, a base station, and a method for the UE to read the MCCH and a user equipment, to ensure that the UE is The correct reception of the notification information enables the UE to read the MCCH and obtain the MBMS in time, improve the robustness of the UE to receive the MBMS, and reduce the probability of the UE losing the MBMS service.

 The method for the base station to notify the user equipment to read the MCCH information of the multicast control channel, which is provided by the embodiment of the present invention, includes:

 The base station determines that there is a new multimedia broadcast multicast service MBMS session start Session Start;

 The base station sends, in an MCCH modification period, N times to notify the user equipment UE to read the notification information of the MCCH information to the UE, where N>1.

 A communication system according to an embodiment of the present invention includes: a base station and at least one user equipment UE; and a base station, configured to: when determining a session start Session Start of a new multimedia broadcast multicast service MBMS, in a multicast control channel MCCH Sending notification notification information to the UE for informing the UE to read the MCCH information in the modification period, where N>1;

 The UE is configured to listen to the notification information sent by the base station M times in an MCCH modification period, and read the MCCH information according to the monitored notification information, where 1<M<=N.

 A method for a user equipment to read a MCCH information of a multicast control channel according to an embodiment of the present invention includes:

 The user equipment UE listens to the notification notification information sent by the M base station in an MCCH ^i change period, where the notification information is that the base station determines that the session of the new multimedia broadcast multicast service MBMS currently exists, the Session Start, tampering in an MCCH 4 Sending N times in the period, informing the user equipment that the UE reads the MCCH information, where N>1, 1<M<=N;

 The UE reads the MCCH information according to the monitored notification information.

 A base station provided by an embodiment of the present invention includes:

 Determining a session start unit, configured to trigger sending a notification information unit when determining that a session start session Start is currently existing in the new multimedia broadcast multicast service MBMS;

The sending notification information unit is configured to, when receiving the trigger for determining the session start unit, send, in a multicast control channel MCCH modification period, N notification information for notifying the user equipment UE to read the MCCH information. UE, where N>1. A user equipment provided by the embodiment of the present invention includes:

 The notification information unit is configured to listen to the notification notification information sent by the base station in the MCCH modification period, where the notification information is that the base station determines that the session of the new multimedia broadcast multicast service MBMS currently exists, the Session Start, in an MCCH modification. The system sends the N times to notify the user equipment that the UE reads the MCCH information, where N>1, 1<M<=N; and passively reads the MCCH information unit, and is configured to read the MCCH information according to the monitored Notification information.

 In the embodiment of the present invention, when determining that there is a new Session Start of the MBMS, the base station sends the notification information for informing the UE to read the MCCH information to the UE multiple times in one MCCH modification period; the UE is multiple times in one MCCH modification period. Listening to the Notification information sent by the base station, and reading the MCCH information according to the notified Notification information, so as to ensure that the UE can correctly receive the Notification information, thereby ensuring that the UE can read the MCCH information and receive the MBMS service in time, thereby improving the UE. Receiving the robustness of the MBMS reduces the probability of the UE losing the MBMS service. DRAWINGS

 1 is a schematic diagram of a relationship between a modification period and a repetition period of a MCCH in the prior art; FIG. 2 is a schematic diagram of sending a notification information in the prior art;

 FIG. 3 is a schematic flowchart of a method for a UE to read an MCCH according to an embodiment of the present invention; FIG. 4 is a schematic diagram of sending Notification information by using a paging subframe according to an embodiment of the present invention; FIG. 6 is a schematic structural diagram of a communication system according to an embodiment of the present invention, which includes a schematic structural diagram of a base station and a user equipment according to an embodiment of the present invention. detailed description

The embodiment of the invention provides a method, a system and a device for a UE to read an MCCH, so as to ensure that the UE correctly receives the notification information, so that the UE can read the MCCH in time and obtain The MBMS improves the robustness of the UE receiving the MBMS and reduces the probability that the UE loses the MBMS service. The technical solutions provided by the embodiments of the present invention are described below with reference to the accompanying drawings.

 Referring to FIG. 3, a method for a UE to read MCCH information according to an embodiment of the present invention includes the following steps: Step S101: A base station determines that a new MBMS session is currently present.

 5102. The base station sends, in an MCCH modification period, multiple pieces of notification information used to notify the UE to read the MCCH information to the UE.

 5103. The UE monitors the notification information sent by the base station multiple times in an MCCH modification period, and reads the MCCH information according to the monitored notification information.

 In the embodiment of the present invention, the subframe carrying the notification information is called a Notification subframe.

Notification Sub-frame, ■ Each Notification sub-I" carries a Notification message, and the Notification information can be M-RNTI.

 The specific subframes in the embodiment of the present invention may be preset by the base station, and may be notified to the UE through system information broadcast, or may be pre-agreed by the base station and the UE.

 Preferably, when there is a MBMS Session Start, the base station sends N (N>1) notification information in the current or next MCCH modification period. If there is no MBMS Session Start, the base station does not send the notification information.

 Preferably, the UE may monitor the Notification subframe M times in any one of the MCCH modification periods, where 1<M<=N, that is, the number of times the UE listens to the notification information may be less than or equal to the number of times the base station sends the notification information. The value of M may be preset by the UE itself, or set by the base station, and notified to the UE by using system information broadcast.

 If the base station transmits the notification information by using the paging subframe of all users, the UE listens for the M paging subframes within one MCCH period.

 If the base station transmits the notification information by using a certain N specific subframes, the UE listens to the N subframes M times in one MCCH period.

If the UE detects the Notification information in the monitored Notification subframe, the The UE will read the MCCH information in the next MCCH cycle; if the UE does not detect the Notification information, the UE will continue to listen to the Notification subframe in the next MCCH cycle without reading the MCCH information.

 Preferably, if the UE has not monitored the notification information within the preset waiting notification time, the MCCH is actively read once in the next MCCH modification period.

 The preset waiting for notification time may be configured according to service attributes, and different services may correspond to different waiting notification times. The correspondence between different services and different waiting notification times may be notified to the UE by the base station through system information broadcast, or may be determined by the UE according to the pre-stored setting information.

 Three specific embodiments are given below:

 Embodiment 1: The base station transmits Notification information in the paging subframe of all users.

 As shown in FIG. 4, it is assumed that one MCCH^ tampering period in the MBSFN area is 2.56 seconds (s), and one MCCH repetition period is 640 milliseconds (ms), and the default paging cycle of a certain cell is also 640ms (The length of the default paging cycle and the repetition period may also be different), the base station of the cell will notify the UE in the cell of the modification period, the repetition period, and the default paging cycle of the MCCH through system broadcast.

 Assume that there are two types of services in the current MBSFN area. The duration of the first type of service is shorter, 5 minutes, and the corresponding "waiting for notification time" is 10 seconds, that is, if the UE does not receive the first type of service within 10 seconds. Notification information, the MCCH is actively read in the next MCCH change cycle; the second service has a longer duration of 2 hours, and the corresponding "waiting for notification time" is 5 minutes, that is, if the UE is within 5 minutes If the notification information of the second service is not received, the MCCH is actively read in the next MCCH modification period. The base station broadcasts the "waiting for notification time" corresponding to the two services to the UE through the system information.

For cells in the FDD system (same as the TDD system), paging for all users may only occur in subframes #0, #4, #5, and #9, that is, subframes #0, #4, # of each radio frame. 5 and #9 are paging subframes. If a new MBMS service session starts in the current MCCH modification period, the base station of the cell will send Notification information in all paging subframes in the next MCCH modification period. Specifically, That is, the base station of the cell will send Notification information in subframes #0, #4, #5, and #9 of all radio frames in each of the 640 ms default paging periods in the next 2.56s MCCH modification period, The number of transmissions is: N = 4 X 2.56/0.64 = 16. The Notification information exists in the PDCCH of these subframes in the form of M-RNTI. The base station will then send a new MCCH in the next MCCH 4 change cycle after sending the Notification message.

 A UE that has the MBMS service receiving capability but does not currently receive the MBMS service will listen to the Notification information in its own paging occasion, that is, each paging subframe, assuming that the paging period of the UE is 640 ms, then in an MCCH During the modification period, the total number of times the UE needs to listen for Notification information is: M = 2.56/0.64 = 4. If the UE correctly receives the notification information in a paging subframe, it does not need to continue to monitor whether there is a notification information in the subsequent paging subframe, and only needs to receive a new MCCH in the next MCCH modification period.

 Assuming that the type of the MBMS service that the UE needs to receive is the second type of service, if the UE does not receive the notification information of the second service within 5 minutes, for example, the notification information is lost due to the poor channel quality, the UE may actively The MCCH is actively read once in the next MCCH modification period.

 In the first embodiment, the UE can monitor the notification information four times in an MCCH modification period, so that the notification information can be received more reliably, and the robustness of the notification information is ensured, so that the UE can receive the new MCCH in time and obtain the MBMS service session. Start message. In addition, if the UE does not receive the notification information within a period of time (such as 5 minutes corresponding to the second service), the UE will actively read the MCCH information again, so that the UE can be timely even if the notification information does not reach the UE. The MCCH information is read to further avoid the situation in which the UE loses the MBMS service.

 Embodiment 2: A base station transmits Notification information in a specific subframe.

As shown in FIG. 5, it is assumed that one MCCH modification period in the MBSFN area is 2.56s, the repetition period is 640ms, and the default paging cycle of a certain cell is 640ms, and the base station of the cell broadcasts the MCCH through the system broadcast. The modification period, the repetition period, and the default paging period notify the UEs in the cell. Assume that there are two types of services in the current MBSFN area. The duration of the first type of service is shorter, 5 minutes, and the corresponding "waiting for notification time" is 10 seconds, that is, if the UE does not receive the first type of service within 10 seconds. Notification information, the MCCH is actively read in the next MCCH modification period; the second service has a longer duration of 2 hours, and the corresponding "waiting for notification time" is 5 minutes, that is, if the UE is within 5 minutes If the notification information of the second service is not received, the MCCH is actively read in the next MCCH modification period. The base station broadcasts the "waiting for notification time" corresponding to the two services to the UE through the system information.

 For the cell of the FDD system (the same TDD system), it is assumed that the base station has previously agreed with the UE or the base station notifies the Notification information through the system broadcast that it will only appear in the last N unicast subframes of the MCCH modification period, assuming N=5, if When a new MBMS service session begins, the base station of the cell will send Notification information in the last 5 unicast subframes in the next (or current) MCCH modification period. The Notification information exists in the PDCCH of these subframes in the form of M-RNTI. The base station will then send a new MCCH in the next MCCH modification cycle after the Notification message is sent.

 A UE that has the MBMS service receiving capability but does not currently receive the MBMS service will listen to M notification information in the last five unicast subframes of each MCCH modification period, assuming that M = 4 is set in advance. If the UE successfully receives the notification information in any one of the M unicast subframes, it does not need to continue to monitor whether there is any notification information in the subsequent subframe, and only needs to receive a new MCCH in the next MCCH modification period. .

 It is assumed that the type of the MBMS service that the UE needs to receive is the second type of service. If the UE does not receive the notification information of the second service within 5 minutes, for example, the notification information is lost due to the channel shield difference, the UE can take the initiative. The MCCH is actively read once in the next MCCH 4 change cycle.

In the embodiment 2, the UE can monitor the notification information four times in an MCCH modification period, so that the notification information can be received more reliably, and the robustness of the notification information is ensured, so that the UE can receive the new MCCH in time and obtain the MBMS service session. Start message. In addition, if the UE does not receive Notification within a certain period of time (such as 5 minutes corresponding to the second service) The information also actively reads the MCCH information once, so that even if the notification information does not reach the UE, the UE can read the MCCH information in time, further avoiding the situation in which the UE loses the MBMS service.

 Embodiment 3: A base station sends notification information in a paging subframe and a specific subframe of all users. The technical solution of Embodiment 3, that is, the combination of the technical solutions of Embodiment 1 and Embodiment 2, that is, Embodiment 3 further increases the number of times Notification information is transmitted on the basis of Embodiment 1 and Embodiment 2, and the base station is Notification information is sent by the paging subframe and the specific subframe of all users.

 The UE can independently select which subframes to listen to Notification information, for example, to listen to Notification information in a paging subframe or a specific subframe, or to listen to Notification information several times in a paging subframe, and to monitor Notification in a certain subframe several times. information. If the total number of monitoring times is M, the technical solution can increase the flexibility of the UE to monitor the notification information; if the total number of monitoring times is greater than M times, the robustness of the notification information can be further improved.

 Referring to FIG. 6, a communication system according to an embodiment of the present invention includes: a base station 11 and at least one user equipment UE 12.

 The base station 11 is configured to send, during a multicast control channel MCCH modification period, N notification notification information for notifying the UE 12 to read the MCCH information to the UE 12 when determining that there is currently a new MBMS session start (Session Start). , where N>1.

 The UE 12 is configured to listen to the notification information sent by the base station 11 in an MCCH modification period, and read the MCCH information according to the monitored notification information, where 1<M<=N.

 Preferably, the base station 11 comprises:

 The determining session start unit 111 is configured to trigger the sending of the notification information unit 112 when it is determined that there is currently a new Session Start of the MBMS.

 The sending notification information unit 112 is configured to, when receiving the trigger of the determining session start unit 111, transmit N notification notification information for notifying the UE 12 to read the MCCH information to the UE 12 in one MCCH modification period.

Preferably, the sending Notification information unit 112, when receiving the trigger of the determining session starting unit 111, sends in the current MCCH modification period or the next MCCH modification period. Send N notifications.

 Preferably, the sending Notification information unit 112, when receiving the trigger of the determining session starting unit 111, passes the paging subframe and/or the specific subframe in the current MCCH modification period or the next MCCH modification period. , Send N notification information.

 Preferably, the UE 12 includes:

 The monitoring notification information unit 121 is configured to listen to the notification notification information sent by the M base station in an MCCH modification period, where the notification information is that the base station determines that the session of the new multimedia broadcast multicast service MBMS currently exists, the Session Start, in an MCCH. Sending N times in the modification period, for notifying the user equipment UE to read the MCCH information, where N>1, 1<M<=N;

 The passive read MCCH information unit 122 is configured to read the MCCH information according to the monitored notification information.

 Preferably, the monitoring notification information unit 121 obtains the notification information sent by the base station 11 by monitoring the M paging sub-frames and/or the specific sub-frames in one MCCH modification period. The passive read MCCH information unit 122 reads the MCCH information in the most recent next MCCH modification period based on the notification information transmitted by the base station 11.

 Preferably, the UE 12 further includes:

 The MCCH information unit 123 is configured to actively read the MCCH information when the monitoring notification information unit 121 does not obtain the notification information sent by the base station 11 within a preset waiting notification time.

In summary, in the embodiment of the present invention, when the base station determines that there is a new Session Start of the MBMS, the base station sends the Notification information for informing the UE to read the MCCH information to the UE multiple times in one MCCH modification period; the UE is in an MCCH. During the modification period, the notification information sent by the base station is monitored multiple times, and the MCCH information is read according to the notified Notification information, so as to ensure that the UE can correctly receive the notification information, thereby ensuring that the UE can read the MCCH information and receive the MBMS in time. The service improves the robustness of the UE receiving the MBMS and reduces the probability that the UE loses the MBMS service. The spirit and scope of the Ming. Thus, it is intended that the present invention cover the modifications and the modifications of the invention

Claims

Rights request A method for a base station to notify a user equipment to read a MCCH information of a multicast control channel, which is characterized in that:  The base station determines that there is a new multimedia broadcast multicast service MBMS session start Session Start;  The base station sends, in an MCCH modification period, N times to notify the user equipment UE to read the notification information of the MCCH information to the UE, where N>1.  2. The method according to claim 1, wherein the step of the base station transmitting N times of notification information in an MCCH modification period comprises:  The base station sends N times of notification information through a paging subframe and/or a specific subframe within one MCCH modification period.  The method according to claim 1 or 2, wherein the MCCH modification period comprises: a current MCCH modification period or a next MCCH modification period.  A method for a user equipment to read a multicast control channel MCCH information, which is characterized by:  The user equipment UE listens to the notification notification information sent by the M base station in an MCCH modification period, where the notification information is that the base station determines that the session start Session Start of the new multimedia broadcast multicast service MBMS exists, and sends a N in an MCCH modification period. And instructing the user equipment UE to read the MCCH information, where N>1, 1<M<=N;  The UE reads the MCCH information according to the monitored notification information.  The method according to claim 4, wherein the UE monitors the notification information sent by the base station M times in an MCCH modification period, which specifically includes:  The UE obtains the notification information sent by the base station by listening to the paging subframe and/or the specific subframe of the M times in an MCCH modification period; The step of the UE reading the MCCH information according to the notified Notification information includes: The UE reads the MCCH information in the latest next MCCH modification period according to the monitored Notification information.  The method according to claim 5, wherein the specific subframe is notified to the UE by the base station through system information broadcast, or is pre-agreed by the base station and the UE. .  The method according to claim 5 or 6, wherein the UE obtains the notification information sent by the base station by listening to the paging subframe and/or the specific subframe of the M times in an MCCH modification period. The steps include:  The UE obtains the notification information sent by the base station by listening to the paging subframe and/or the specific subframe of the M times in an MCCH modification period according to the value of the M that is preset in the system or broadcasted by the system information.  8. The method according to claim 4, 5 or 6, further comprising:  If the UE does not receive the notification information sent by the base station within a preset waiting notification time, the UE actively reads the MCCH information.  The method according to claim 8, wherein the waiting for notification time is notified by the base station to the UE through system information broadcast, or is determined by the UE according to the setting information.  10. A communication system, the system comprising: a base station and at least one user equipment UE;  a base station, configured to send, during a multicast control channel MCCH modification period, N notification notification information for notifying the UE to read the MCCH information to the UE, when determining that a session start session of the new multimedia broadcast multicast service MBMS is currently present. , where N>1;  The UE is configured to listen to the notification information sent by the base station M times in an MCCH modification period, and read the MCCH information according to the monitored notification information, where 1<M<=N.  A base station, the base station comprising: Determining a session start unit, configured to trigger sending a Notification information element when it is determined that a session start Session Start of a new multimedia broadcast multicast service MBMS exists; And sending a notification information unit, configured to send, when a trigger of the determining session start unit is received, a notification notification information for notifying the user equipment UE to read the MCCH information to the UE in a multicast control channel MCCH modification period, Where N>1.  The base station according to claim 11, wherein the sending notification information unit, when receiving the trigger for determining the session start unit, searching through the current MCCH modification period or the next MCCH modification period The subframe information and/or the specific subframe are sent N times Notification information.  13. A user equipment, comprising:  The notification information unit is configured to listen to the notification notification information sent by the base station in the MCCH modification period, where the notification information is that the base station determines that the session of the new multimedia broadcast multicast service MBMS currently exists, the Session Start, in an MCCH modification. The system sends the N times to notify the user equipment that the UE reads the MCCH information, where N>1, 1<M<=N; and passively reads the MCCH information unit, and is configured to read the MCCH information according to the monitored Notification information.  14. Apparatus according to claim 13 wherein:  The monitoring notification information unit is specifically configured to obtain the notification information sent by the base station by listening to the paging subframe and/or the specific subframe of the M times in an MCCH modification period; and the passively reading the MCCH information unit, Specifically, the MCCH information is read in the latest MCCH modification period according to the Notification information sent by the base station.  The device according to claim 13 or 14, wherein the UE further comprises: an active reading MCCH information unit, configured to: when the monitoring notification information unit does not get in the preset waiting for notification time When the notification information sent by the base station is described, the MCCH information is actively read.