Mobile communication system and mobile terminal

The present invention relates to a mobile communication system capable of notifying emergency information by a broadcast multimedia service, and a base station and a mobile terminal constituting the mobile communication system.

In recent years, in the event of an emergency such as an earthquake or tsunami, there is an increasing social need for a system that can immediately notify a large number of people of the emergency information. On the other hand, the market size of mobile terminals such as mobile phones is increasing year by year, and in Japan, it has exceeded 90 million units, and many people are in a social situation where they have mobile phones. Therefore, information distribution using a mobile terminal via a mobile communication network can be an effective means of notifying emergency information.

For example, J-ALERT (National Instant Alert System) is being considered as a system for notifying emergency information. This system is supposed to use the disaster prevention radio of the local government and notify emergency information mainly through the disaster prevention broadcasting speakers installed indoors and outdoors. However, with voice notification by a speaker, emergency information may not be known to a person or the like living in an area away from the speaker.

Therefore, a system has been proposed in which emergency information is notified by voice or e-mail to a mobile terminal managed by a user registered in the service via an existing mobile communication network. It is also considered to notify an unspecified number of users of emergency information by using terrestrial digital broadcasting.

In a mobile communication system, for example, there is a CBS (Cell Broadcast Short message service) as a service for notifying an unspecified number of users of information (see Non-Patent Document 1). This CBS is a one-to-many service that enables broadcast communication to mobile terminals under the umbrella of a base station that provides services in a mobile communication system. The 3GPP (3rd Generation Partnership Project) defines the Idle state, CELL_DCH state, CELL_FACH state, CELL_PCH state, and URA_PCH state as possible states of the mobile terminal (see Non-Patent Document 2). In the mobile communication system, the mobile terminal operates while shifting these states at any time.

Further, as a conventional emergency information notification system using a mobile communication network, for example, there is one disclosed in Patent Document 1. In this system, the base station uses the notification information transmitted to all the mobile terminals under its umbrella to notify the emergency information, and the notification information includes the channel information for receiving the emergency information and the identifier of the emergency information. Can be assigned as a parameter, and the channel to which emergency information is transmitted can be received based on this parameter.

On the other hand, in a mobile communication system, as a service suitable for transmitting emergency information to an unspecified number of user terminals, a broadcast multimedia service capable of delivering one transmission data to the mobile terminals of a plurality of users at the same time is available. It is being considered. In this broadcast-type multimedia service, as a service of a mobile communication system, multimedia information such as sports broadcasting, weather forecast, and radio is simultaneously distributed to mobile terminals of a plurality of users. This technology is called MBMS (Multimedia Broadcast Multicast Service) in 3GPP (see Non-Patent Document 3).

MBMS assumes multimedia services as described above, and supports high-speed forwarding of videos and the like. Therefore, it is possible to transmit a large amount of information at a higher rate than CBS, and it is suitable for a system for notifying emergency information according to the needs of an unspecified number of users.

As shown in Non-Patent Document 3, three logical channels (MCCH, MTCH, MSCH) are introduced as radio section channels used for MBMS, and MICH (MBMS Indicator CHannel) is introduced as an indicator similar to PICH. Has been done. MCCH (MBMS Control CHannel) is a channel on which MBMS control information is stored, and MTCH (MBMS Traffic CHannel) is a channel on which MBMS data is stored. MICH has the same physical structure as PICH of the R99 (Release 99) standard in 3GPP, and this bit is set in advance when information is posted on MCCH.

The mobile terminal receives the MBMS data on the MTCH according to the MBMS control channel (MCCH). When some information is included in the MCCH, the MICH bit, which is an indicator for MBMS notification, is set, and when the mobile terminal recognizes the bit, the mobile terminal receives the MCCH containing the new control information. In this case, the mobile terminal receives the MTCH containing the MBMS data according to the newly received MCCH.

In addition, the procedure for receiving MCCH does not depend on the possible states of the mobile terminal (Idle state, RRC connected state (RRC_Connected) (CELL_DCH state, CELL_FACH state, CELL_PCH state, URA_PCH state)), and all that support MBMS. It is applied to mobile terminals of (see Non-Patent Document 4). Therefore, the mobile terminal can receive the MBMS data in any of the above-mentioned states.

In 3GPP, as a communication method different from W-CDMA, "Long Term Evolution LTE" for the wireless section and "System Architecture Evolution SAE" for the entire system configuration including the core network. ) Is being studied for a new communication method. The LTE access method uses OFDM (Orthogonal Frequency Division Multiplexing) in the downlink direction and SC-FDMA (Single Career Frequency Division Multiple Access) in the uplink direction. In addition, the bandwidth can be selected for each base station within 1.4 / 3/5/10/15 / 20MHz in LTE, while W-CDMA is 5MHz. In LTE, unlike W-CDMA, circuit switching is not included, and only packet communication is used.

In LTE communication systems, the base station (Base station) that communicates with mobile terminals (UE: User Equipment) is eNB (E-UTRAN Node B), and base station control that exchanges control data and user data with multiple base stations. The device (Radio Network Controller) is called EPC (Evolved Packet Core) (aGW: sometimes called Access Gateway). This LTE communication system provides a Unicast service and an Evolved Multimedia Broadcast Multicast Service. The E-MBMS service is a broadcast multimedia service, and is sometimes referred to simply as MBMS. Large-capacity broadcast content such as news, weather forecasts, and mobile broadcasts are transmitted to multiple mobile terminals. This is also called a point-to-multipoint service.

Non-Patent Document 5 describes the current decisions regarding the overall architecture of LTE systems at 3GPP. The overall architecture will be described with reference to FIG. 11 (see Chapter 4 of Non-Patent Document 5). FIG. 11 is an explanatory diagram showing a configuration of an LTE communication system. In FIG. 11, the control protocol for the mobile terminal 101 (for example, RRC (Radio Resource Management)) and the user plane (for example, PDCP: Packet Data Convergence Protocol, RLC: Radio Link Control, MAC: Medium Access Control, PHY: If the physical layer) is terminated at base station 102, E-UTRAN (Evolved Universal Terrestrial Radio Access) is composed of one or more base stations 102. The base station 102 performs scheduling and transmission of a paging signal (also referred to as a paging signaling or paging message) notified from the MME 103 (Mobility Management Entity). Base stations 102 are connected to each other by an X2 interface. The base station 102 is connected to the EPC (Evolved Packet Core) by the S1 interface, more specifically, is connected to the MME103 (Mobility Management Entity) by the S1_MME interface, and is connected to the S-GW104 (Serving Gateway) by the S1_U interface. Interface. The MME 103 distributes the paging signal to a plurality of or a single base station 102. In addition, MME103 is in standby state (Idle) Performs Mobility control of the State. The S-GW104 sends and receives user data to and from one or more base stations 102.

The current decisions regarding frame configurations in LTE systems at 3GPP are described in Non-Patent Document 5 (Chapter 5). This will be described with reference to FIG. FIG. 12 is an explanatory diagram showing a configuration of a wireless frame used in an LTE communication system. In FIG. 12, one radio frame is 10 ms. The radio frame is divided into 10 equally sized Sub-frames. The subframe is divided into two equally sized slots. Each frame contains the Downlink Synchronization Channel (SCH) in the 1st (# 0) and 6th (# 5) subframes. The synchronization signals include the primary synchronization channel (P-SCH) and the secondary synchronization channel (P-SCH). There is S-SCH). Channels other than MBSFN (Multimedia Broadcast multicast service Single Frequency Network) and channels other than MBSFN are multiplexed in subframe units. Hereinafter, the subframe for MBSFN transmission will be referred to as MBSFN sub-frame. Non-Patent Document 5 describes an example of signaling when an MBSFN subframe is assigned. FIG. 13 is an explanatory diagram showing the configuration of the MBSFN frame. In FIG. 13, MBSFN subframes are assigned to each MBSFN frame. An MBSFN frame cluster is scheduled. A Repetition Period is assigned to the set of MBSFN frames.

Non-Patent Document 5 describes the current decisions regarding channel configuration in LTE systems at 3GPP. The physical channel will be described with reference to FIG. 14 (see Chapter 5 of Non-Patent Document 5). FIG. 14 is an explanatory diagram illustrating a physical channel used in an LTE communication system. In FIG. 14, the physical broadcast channel 401 (PBCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. BCH transport blocks are mapped to 4 subframes at 40ms intervals. There is no explicit signaling for 40ms timing. Physical Control format indicator channel 402 (Physical Control format indicator channel: PCFICH) is transmitted from the base station 102 to the mobile terminal 101. PCFICH notifies the mobile terminal 101 from the base station 102 about the number of OFDM symbols used for PDCCHs. PCFICH is transmitted every subframe. The physical downlink control channel 403 (PDCCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. PDCCH is resource allocation, HARQ information about DL-SCH (downstream shared channel, which is one of the transport channels shown in Figure 15), and paging, which is one of the transport channels shown in Figure 15. Channel) is notified. The PDCCH carries the Uplink Scheduling Grant. The PDCCH carries ACK / Nack, which is a response signal for uplink transmission. Physical downlink shared channel 404 (Physical downlink shared channel: PDSCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. DL-SCH (downlink shared channel), which is a transport channel, is mapped to PDSCH. The physical multicast channel 405 (PMCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. PMCH is mapped to MCH (multicast channel), which is a transport channel.

The physical uplink control channel 406 (PUCCH) is an uplink transmitted from the mobile terminal 101 to the base station 102. PUCCH carries ACK / Nack, which is a response signal for downlink transmission. PUCCH carries a CQI (Channel Quality indicator) report. CQI is quality information indicating the quality of received data or the quality of communication paths. The physical uplink shared channel 407 (PUSCH) is an uplink transmitted from the mobile terminal 101 to the base station 102. PUSCH is mapped to UL-SCH (uplink shared channel, which is one of the transport channels shown in Fig. 15). Physical Hybrid ARQ indicator channel 408 (Physical Hybrid ARQ indicator channel: PHICH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. PHICH carries ACK / Nack, which is the response to uplink transmission. The physical random access channel 409 (PRACH) is an uplink channel transmitted from the mobile terminal 101 to the base station 102. PRACH carries a random access preamble.

The transport channel will be described with reference to FIG. 15 (see Chapter 5 of Non-Patent Document 5). FIG. 15 is an explanatory diagram illustrating a transport channel used in an LTE communication system. Figure 15A shows the mapping between the downlink transport channel and the downlink physical channel. Figure 15B shows the mapping between the uplink transport channel and the uplink physical channel. About the downlink transport channel The broadcast channel (BCH) is broadcast to the entire base station (cell). BCH is mapped to the physical broadcast channel (PBCH). Downlink Shared channel: Retransmission control by HARQ (Hybrid ARQ) is applied to DL-SCH). It is possible to notify the entire base station (cell). Supports dynamic or semi-static resource allocation. Quasi-static resource allocation is also known as Persistent Scheduling. Supports DRX (Discontinuous reception) of mobile terminals to reduce power consumption of mobile terminals. DL-SCH is mapped to a physical downlink shared channel (PDSCH). The Paging channel (PCH) supports DRX on mobile terminals to enable low power consumption on mobile terminals. Notification to the entire base station (cell) is required. It is dynamically mapped to a physical resource such as a physical downlink shared channel (PDSCH) or another control channel such as a physical downlink control channel (PDCCH). Multicast channel: MCH) is used to notify the entire base station (cell). Supports SFN synthesis of MBMS services (MTCH and MCCH) for multi-cell transmission. Supports quasi-static resource allocation. MCH is mapped to PMCH.

Retransmission control by HARQ (Hybrid ARQ) is applied to the uplink shared channel (UL-SCH). Supports dynamic or semi-static resource allocation. UL-SCH is mapped to a physical uplink shared channel (PUSCH). The Random access channel (RACH) shown in Figure 15B is limited to control information. There is a risk of collision. RACH is mapped to a physical random access channel (PRACH).

The logical channel will be described with reference to FIG. 16 (see Chapter 6 of Non-Patent Document 56). FIG. 16 is an explanatory diagram illustrating a logical channel used in an LTE communication system. Figure 16A shows the mapping between the downlink logical channel and the downlink transport channel. Figure 16B shows the mapping between the uplink logical channel and the uplink transport channel. Broadcast control channel (BCCH) is a downlink channel for broadcast system control information. BCCH, which is a logical channel, is mapped to a broadcast channel (BCH), which is a transport channel, or a downlink shared channel (DL-SCH). Paging control channel: PCCH) is a downlink channel for transmitting a paging signal. PCCH is used when the network does not know the cell location of the mobile terminal. The logical channel PCCH is mapped to the transport channel paging channel (PCH). A common control channel (CCCH) is a channel for transmission control information between a mobile terminal and a base station. CCCH is used when the mobile terminal does not have an RRC connection to the network. It has not yet been decided whether CCCH will be provided on the downstream side. In the uplink direction, CCCH is mapped to the transport channel, the uplink shared channel (UL-SCH).

Multicast control channel (MCCH) is a downlink channel for one-to-many transmission. A channel used to transmit MBMS control information for one or several MTCHs from a network to a mobile terminal. MCCH is a channel used only for mobile terminals receiving MBMS. The MCCH is mapped to the transport channel, the downlink shared channel (DL-SCH) or the multicast channel (MCH). Dedicated control channel (DCCH) is a channel that transmits individual control information between a mobile terminal and a network. DCCH is mapped to the uplink shared channel (UL-SCH) on the uplink and to the downlink shared channel (DL-SCH) on the downlink. Dedicated Traffic channel: DTCH) is a one-to-one communication channel to individual mobile terminals for transmitting user information. DTCH exists both up and down. DTCH is mapped to the uplink shared channel (UL-SCH) on the uplink and to the downlink shared channel (DL-SCH) on the downlink. Multicast Traffic channel (MTCH) is a downlink channel for transmitting traffic data from a network to a mobile terminal. MTCH is a channel used only for mobile terminals receiving MBMS. MTCH is mapped to a downlink shared channel (DL-SCH) or a multicast channel (MCH).

The current decisions regarding E-MBMS services at 3GPP are described in Non-Patent Document 5. The definition of terms related to E-MBMS will be explained with reference to FIG. 17 (see Non-Patent Document 5 Chapter 15). FIG. 17 is an explanatory diagram illustrating the relationship between the MBSFN synchronization area and the MBSFN area. In FIG. 17, the MBSFN synchronization area 701 (Multimedia Broadcast multicast service Single Frequency Network Synchronization Area) is a network area in which all base stations are synchronized and MBSFN (Multimedia Broadcast Multicast service Single Frequency Network) transmission can be executed. That is. The MBSFN sync area contains one or more MBSFN Areas 702. In one frequency layer, a base station can belong to only one MBSFN synchronization area. MBSFN Area 702 (MBSFN Area) is composed of a group of base stations (cells) included in the MBSFN synchronization area of the network. Base stations (cells) in the MBSFN synchronization area may form multiple MBSFN areas.

The logical architecture of E-MBMS will be described with reference to FIG. 18 (see Chapter 15 of Non-Patent Document 5). FIG. 18 is an explanatory diagram illustrating the logical architecture of the E-MB MS. In FIG. 18, the Multi-cell / multicast Coordination Entity: MCE) is a logical entity. The MCE801 allocates radio resources to all base stations in the MBSFN area for multi-cell MBMS transmission. In addition to allocating time or / and frequency radio resources, the MCE801 makes decisions about the details of the radio structure (eg, modulation scheme, code, etc.). E-MBMS Gateway 802 (MBMS GW) is a logical entity. The E-MBMS gateway 802 is located between the eBMSC and the base station, and its main function is to transmit / broadcast the MBMS service to each base station using the SYNC protocol. The M3 interface is a control plane interface between MCE801 and E-MBMS gateway 802. The M2 interface is a control interface between MCE801 and eNB102. The M1 interface is a user plane interface between the E-MBMS gateway 802 and the eNB 102.

The architecture of E-MBMS will be described (see Non-Patent Document 5 Chapter 15). FIG. 19 is an explanatory diagram illustrating the architecture of the E-MBMS. There are two possible E-MBMS architectures, as shown in Figures 19A and 19B. The MBMS cell will be described (see Non-Patent Document 5 Chapter 15). In LTE systems, there are MBMS dedicated cells (MBMS-dedicated cells) and MBMS / Unicast -mixed cells that can execute both MBMS and unicast services.

MBMS transmission will be described (see Non-Patent Document 5 Chapter 15). MBMS transmission on LTE systems supports single-cell transmission (SC transmission) and multi-cell transmission (MC transmission). Single cell transmission does not support SFN (Single frequency Network) operations. It also supports SFN operations for multi-cell transmission. MBMS transmissions are synchronized in the MBSFN (Multimedia Broadcast multicast service Single Frequency Network) area. SFN combining of MBMS services (MTCH and MCCH) in multi-cell transmission is supported. MTCH and MCCH are mapped to MCH by one-to-many transmission. Scheduling is done by MCE.

The multicast control channel (MCCH) structure (Structure) will be described (see Non-Patent Document 5 Chapter 15). The downlink logic channel, the broadcast control channel (BCCH), indicates the scheduling of one or two primary multicast control channels (Primary MCCH: P-MCCH). P-MCCH for single cell transmission is mapped to DL-SCH (downlink shared channel). In addition, P-MCCH for multi-cell transmission is mapped to MCH (multicast channel). When a secondary multicast control channel (Secondary MCCH: S-MCCH) is mapped on the MCH, the address of the secondary multicast control channel (S-MCCH) can be indicated using the primary multicast control channel (P-MCCH). The Broadcast Control Channel (BCCH) indicates the resources of the Primary Multicast Control Channel (P-MCCH), but does not indicate the available services.

The current decisions regarding paging at 3GPP are described in Non-Patent Document 5 (Chapter 10). The paging group uses the L1 / L2 signaling channel (PDCCH). The clear identifier (UE-ID) of the mobile terminal can be found on the paging channel (PCH).

<nplcit num="1"><text>3GPP standard TS23.041 V3.5.0</text></nplcit><nplcit num="2"><text>W-CDMA mobile communication system Supervised by Keiji Tachikawa Published 2001.6.25 pp. 162-171</text></nplcit><nplcit num="3"><text>3GPP Standard TS25.346 V7.3.0</text></nplcit><nplcit num="4"><text>3GPP Standard TS25.331 V6.6.0</text></nplcit><nplcit num="5"><text>3GPP standard TS36.300 V8.2.0</text></nplcit><patcit num="1"><text>Japanese Patent No. 3529351</text></patcit>

Since the conventional mobile communication system is configured as described above, it is easily affected by the communication line load and is susceptible to emergency information in order to be used as a system for notifying an unspecified number of users of emergency information. There is a problem that the range that can be transmitted is narrow and the information may not be breaking news.

Specifically, the system that notifies the user's mobile terminal of emergency information by voice or e-mail via the existing mobile communication network is the user's mobile terminal registered in the service and the base that provides the service. Information will be provided by one-to-one communication with the station. For this reason, since the service depends on the communication line capacity between the base station and the mobile terminal, if the number of users who notify emergency information increases, the load on the communication line may increase and the notification may not be possible. However, it is not suitable for notifying an unspecified number of users of emergency information.

In addition, in a system that notifies emergency information by terrestrial digital broadcasting, there are many places where reception characteristics are poor, such as indoors, shadows of buildings, underground malls, etc., compared to mobile communication networks, so terrestrial digital broadcasting provides emergency information. It may not be possible to accurately notify. Further, since it is necessary to add hardware for receiving terrestrial digital broadcasting to the mobile terminal, there is a demerit in reducing the size and price of the mobile terminal.

In CBS, the base station and the mobile terminal have one-to-many communication, which is suitable for notifying an unspecified number of users of emergency information. The mobile terminal in the above cannot receive the transmitted data, and only the mobile terminal in the standby (Idle) state can receive the transmitted data. As described above, the mobile terminal operates while shifting from a plurality of states specified in 3GPP at any time. Therefore, if the mobile terminal is in the standby (Idle) state, the notified emergency information can be received, but the emergency information notified that the mobile terminal is in a state other than the standby state cannot be received, and the emergency information cannot be received. Accurate notification may not be given.

In addition, CBS is premised on the transmission of low-rate short messages of about 80 octets from the base station. Therefore, for example, the amount of short message data specified by CBS is not sufficient to notify emergency information according to the user's need, such as map information or image information.

On the other hand, in the system disclosed in Patent Document 1, emergency information can be notified to all mobile terminals under the umbrella registered in the base station. However, Patent Document 1 does not specify what kind of channel the emergency information is transmitted. Therefore, it is not known whether the channel for transmitting emergency information is an individual channel, a notification channel, or a special channel is used, and at what rate emergency information can be transmitted. I have no idea if the information is commensurate with the user's needs.

Further, in Patent Document 1, since the channel information for receiving the emergency information and the identifier of the emergency information must be added as parameters to the broadcast information, the amount of information to be transmitted as the broadcast information is inevitably increased. In general, the broadcast information must include a lot of system information for the base station to transmit to all of its mobile terminals. Therefore, in the method of adding the parameter for transmitting the emergency information to the notification information, it becomes necessary to limit the data amount of the parameter for transmitting the emergency information depending on the amount of information to be transmitted as the notification information, or the parameter. It is also assumed that the amount of information of the notification information to which is given will be excessive.

On the other hand, with MBMS, information can be received regardless of the state specified by 3GPP, and high-speed transfer of moving images, etc. is possible, so the amount of information that meets the needs of users is urgent. Since the information data can be transmitted and it is not necessary to include additional information in the notification information as in Patent Document 1, it is possible to solve the problems assumed in the system of Patent Document 1 described above.

However, in the conventional mobile communication system that performs MBMS, multimedia information can be simultaneously distributed to mobile terminals of a plurality of users, but the user must receive MTCH containing desired data. There was a problem that the information could not be provided and the emergency information might not be prompt.

The present invention has been made to solve the above-mentioned problems, and uses a broadcast multimedia service having a wide range of transmission as emergency information without imposing an excessive load on the mobile communication network. Moreover, it is an object of the present invention to obtain a mobile communication system capable of notifying emergency information without lacking breaking news, and base stations and mobile terminals constituting the mobile communication system.

The mobile communication system according to the present invention includes a plurality of mobile terminals and base stations, and in a mobile communication system capable of delivering emergency information from a base station to a plurality of mobile terminals, the base station has emergency information. Emergency information indicator,<u style="single">Using the channel that sends individual control information,</u>Paging message to mobile terminal receiving individual data among multiple mobile terminals<u style="single">By</u>Information necessary for a mobile terminal that is sending and receiving individual data to receive emergency information<u style="single">Using the downlink shared channel</u>Emergency information that can be received by the mobile terminal that is receiving individual data according to the information required for the mobile terminal that is transmitting and receiving individual data to receive the emergency information.<u style="single">Using the downlink shared channel</u>Mobile terminals that are delivering and receiving individual data<u style="single">Of the channel that sends individual control information</u>Receives an emergency information indicator indicating that there is emergency information sent from the base station by a paging message,<u style="single">By downlink shared channel</u>The mobile terminal receiving the individual data transmitted from the base station receives the information necessary for receiving the emergency information, and after receiving the emergency information indicator, the mobile terminal receiving the individual data receives the emergency information. From the base station according to the information required to<u style="single">By downlink shared channel</u>It is characterized in that it starts receiving the delivered emergency information.

According to the present invention<u style="single">Send individual control information</u>Since the presence or absence of emergency information is notified to the mobile terminal from the contents of the flag indicating the presence or absence of emergency information provided in the channel.<u style="single">Emergency information can also be notified to mobile terminals that are receiving individual data that is in a state other than standby.</u>In addition, it has the effect of ensuring breaking news and notifying emergency information.

<figref num="1">It is a figure which shows the structure of the mobile communication system by this invention.</figref><figref num="2">It is a figure which shows the channel handled by the mobile communication system by this invention.</figref><figref num="3">It is a figure which shows the structure of the mobile terminal in FIG.</figref><figref num="4">It is a figure which shows the structure of the base station in FIG.</figref><figref num="5">It is a figure which shows the structure of the base station control device in FIG.</figref><figref num="6">It is a flowchart which shows the notification processing of the emergency information by the mobile communication system of Embodiment 1.</figref><figref num="7">It is a flowchart which shows the notification processing of the emergency information by the mobile communication system of Embodiment 2.</figref><figref num="8">It is a flowchart which shows the notification processing of the emergency information by the mobile communication system of Embodiment 3.</figref><figref num="9">It is a flowchart which shows the notification processing of the emergency information by the mobile communication system of Embodiment 4.</figref><figref num="10">It is a flowchart which shows the notification processing of the emergency information by the mobile communication system of Embodiment 5.</figref><figref num="11">It is explanatory drawing which shows the structure of the LTE system communication system. It is explanatory drawing which shows the structure of the LTE system communication system.</figref><figref num="12">It is explanatory drawing which shows the structure of the wireless frame used in the LTE communication system.</figref><figref num="13">It is explanatory drawing which shows the structure of the MBSFN (Multimedia Broadcast multicast service Single Frequency Network) frame.</figref><figref num="14">It is explanatory drawing explaining the physical channel used in the LTE communication system.</figref><figref num="15">It is explanatory drawing explaining the transport channel used in the LTE communication system.</figref><figref num="16">It is explanatory drawing explaining the logical channel used in the LTE communication system.</figref><figref num="17">It is explanatory drawing explaining the relationship between MBSFN synchronization area and MBSFN area.</figref><figref num="18">It is explanatory drawing explaining the logical structure (logical architecture) of E-MBMS.</figref><figref num="19">It is explanatory drawing explaining the architecture (Architecture) of E-MBMS.</figref>

Hereinafter, in order to explain the present invention in more detail, the best mode for carrying out the present invention will be described with reference to the accompanying figures. Embodiment 1. In the first embodiment, an emergency information flag (emergency information indicator) indicating the presence or absence of emergency information is provided in the MCCH, which is an MBMS control channel, so that the mobile terminal can periodically check the presence or absence of emergency information. As a result, even if the mobile terminal is receiving information other than the emergency information in the MBMS, the emergency information flag can recognize the existence of the emergency information and receive the emergency information channel in the MBMS.

FIG. 1 is a diagram showing a configuration of a mobile communication system according to the present invention. In this system, MBMS is used to notify all MBMS-compatible mobile terminals 1 of emergency information. In FIG. 1, the mobile communication system according to the present invention includes a mobile terminal 1, a base station 2, a base station control device 3, SGSN4, GGSN5, and a service center 6. The mobile terminal 1 is a communication device that receives data from one or a plurality of base stations 2. The base station 2 transmits / receives data to / from the mobile terminal 1 in the cell covered by the base station 2. The base station control device 3 connects to a plurality of base stations 2 to control the communication of each base station 2, and also connects to the SGSN 4 to relay the communication between the base station 2 and the SGSN 4.

SGSN (Service GPRS Support Node) 4 is a node in charge of packet communication in mobile communication systems, and authentication, service subscription, routing, mobility management, and management of individual users registered in GPRS (General Packet Radio Service). Handles service restrictions, context storage, billing information, etc.

The GGSN (GPRS Gateway Support Node) 5 is a node that functions as a gateway to an external network (for example, an Internet network), and secures a path for packets transmitted from SGSN4 or received by SGSN4. In addition to the gateway function, the GGSN5 also performs processing such as billing information collection, mobility management, QoS (Quality of Service) negotiation, and policy control for adjusting traffic.

The service center 6 is a communication node that connects to an external network, stores content for providing services, and delivers the content, and transmits data related to the content to the GGSN 5 in accordance with a request from the user. In the W-CDMA system, the mobile terminal 1 may be called UE (User Equipment), the base station 2 may be called Node-B, and the base station controller 3 may be called RNC (Radio Network Controller).

Next, channels used for packet communication such as MBMS will be described. FIG. 2 is a diagram showing channels handled by the mobile communication system according to the present invention, and shows channels used for packet communication such as MBMS. First, the physical channels in the downward direction from the base station 2 to the mobile terminal 1 include CPICH, P-CCPCH, S-CCPCH, PICH, and MICH.

CPICH (Common Pilot CHannel) is a channel used for channel estimation in mobile terminal 1, cell search, and timing reference of all downward physical channels in a cell, and all mobile terminals 1 in a cell. Is sent to.

The P-CCPCH (Primary-Common Control Physical CHannel) is a channel for notifying each mobile terminal 1 in the cell of other notification information. In P-CCPCH, BCH (Broadcast CHannel; broadcast information channel) is transmitted. BCCH (Broadcast Control CHannel) is mapped to BCH.

S-CCPCH (Secondary-Common Control Physical CHannel) is a channel for transmitting signaling and data to each mobile terminal 1 in a cell, and it is allowed to have a plurality of S-CCPCH (Secondary-Common Control Physical CHannel). In S-CCPCH, PCH (Paging CHannel; paging channel) and FACH (Forward Link Access CHannel) are transmitted. PCCH (Paging Control CHannel) is mapped to PCH.

FACH includes BCCH (Broadcast Control CHannel), CCCH (Common Control Channel), CTCH (Common Traffic CHannel), DCCH (Dedicated Control CHannel), and DTCH. (Dedicated Traffic CHannel), MCCH (MBMS point-to-multipoint Control CHannel), MTCH (MBMS point-to-multipoint Traffic CHannel; MBMS traffic channel) are mapped.

PICH (Paging Indicator CHannel) is a transmission channel for a downward paging indicator, and MICH (MBMS Notification Indicator CHannel) is a transmission channel for a downward MBMS notification indicator.

Next, as an uplink common channel from the mobile terminal 1 to the base station 2, there is a RACH (Random Access CHannel), which is a channel used for transferring control information and short packets from the mobile terminal 1. DPCH (Dedicated Physical CHannel) is used as a channel in both directions in the up direction or the down direction, and is individually set for communication between a specific mobile terminal 1 and a base station 2. This DPCH is used for communication of individual data such as voice and data and signaling of higher layers.

The DPCH has a DPDCH (Dedicated Physical Data CHannel) for transmitting data and a DPCCH (Dedicated Physical Control CHannel) for transmitting bits related to control. In DPCH, DCH (Dedicated CHannel) is transmitted. DCCH and DTCH are mapped to DCH. The DPCH is called an individual channel because it is used by each mobile terminal 1, and the other channels are called a common channel because it is commonly used by a plurality of mobile terminals 1.

In the above description, the channel configuration in the radio section between the base station 2 and the mobile terminal 1 in the W-CDMA system has been described, but it can also be applied to other communication systems. Further, as the above-mentioned channel, any channel may be used as long as it is a channel for transmitting similar data. For example, it is also possible to share the above-mentioned plurality of channels with one channel.

Here, the outline of MBMS data distribution by the mobile communication system of the present invention will be described with reference to FIGS. 1 and 2. The service may be requested from the mobile terminal 1, but the case where the data is delivered from the content server will be described as an example. First, the content provider in the external network transmits multimedia data and the like (MBMS data) to the service center 6. The service center 6 stores the multimedia data received from the content provider and transfers the multimedia data to the SGSN4 that manages the mobile terminal 1 that uses the multimedia service via the GGSN5.

The SGSN4 transmits multimedia data to the base station 2 via the base station control device 3, and the base station 2 distributes the multimedia data to the mobile terminal 1 in the cell managed by itself using S-CCPCH. The mobile terminal 1 receives the S-CCPCH data of any one of the base stations 2 and receives the multimedia data from the base station 2. At this time, if the mobile terminal 1 is located at the cell edge or the like and the reception state of the S-CCPCH data transmitted from one base station 2 is not good, the mobile terminal 1 of the S-CCPCH transmitted from the other base station 2 Data is also received and selective synthesis is performed for two or more channels to improve reception quality.

Next, the mobile terminal 1 constituting the mobile communication system according to the present invention will be described. FIG. 3 is a diagram showing a configuration of a mobile terminal in FIG. In FIG. 3, the mobile terminal 1 includes an application processing unit 7, a protocol processing unit 8, an uplink common channel transmission unit 9, an uplink individual channel transmission unit 10, a modulation unit 11, a code generator 12, a D / A converter 13, and a frequency. Conversion unit 14, power amplification unit 15, antenna 16, low noise amplification unit 17, frequency conversion unit 18, A / D converter 19, receiver 20a to 20c, code generator 23, search unit 24, finger assignment control unit 25 , Input memory 26, decoding unit 27, output memory 28, broadcast information receiving unit 29, downlink individual channel receiving unit 30, downlink common channel receiving unit 31, selection unit 32, and control unit 33.

The application processing unit 7 performs man-machine interface processing such as conversion processing of voice codecs and image codecs, key input, and image display on a display device (not shown), and performs uplink common channel transmission unit 9 and uplink individual channel transmission unit. Information such as data to be transmitted and transmission request is supplied to 10. The protocol processing unit 8 executes processing related to communication control such as channel setting, channel release, and handover in response to a request input from the application processing unit 7. For example, in the case of the outgoing call processing of the mobile terminal 1, the application processing unit 7 accepts the input of the telephone number from the user and makes a outgoing call request to the protocol processing unit 8. Further, the protocol processing unit 8 controls the uplink common channel transmission unit 9 and the uplink individual channel transmission unit 10 in order to transmit necessary control information, thereby connecting to the base station 2 according to the protocol defined by the communication standard. Perform processing.

The uplink common channel transmission unit 9 and the uplink individual channel transmission unit 10 perform coding processing such as turbo coding and control of transmission timing on the transmission data, and output the coded data to the modulation unit 11. The modulation unit 11 diffuses and modulates the signals output from the uplink common channel transmission unit 9 and the uplink individual channel transmission unit 10 by using the channelization code and the scrambling code generated by the code generator 12. The modulated signal is converted from digital data to an analog signal by the D / A converter 13, and is converted into an RF (Radio Frequency) signal by the frequency conversion unit 14. The power amplification unit 15 amplifies the converted signal to a desired power and outputs it to the antenna 16. The antenna 16 transmits the amplified signal as a radio signal to the base station 2.

The low noise amplification unit 17 amplifies the power of the weak signal received via the antenna 16. The frequency conversion unit 18 converts the signal amplified by the low noise amplification unit 17 into a baseband signal. The A / D converter 19 converts the analog baseband signal input from the frequency converter 18 into a digital signal. The receiving units 20a to 20c include a plurality of finger units 21 and a synthesizing unit 22 that synthesizes these outputs, and despreads the received signal of each path using the channelization code and scrambling code input from the code generator 23. Then, the signal of the channel assigned to itself is received by rake-synthesizing the result of back-diffusion. A plurality of finger units 21 are provided in each of the receiving units 20a to 20c, receive signals of each path assigned by the finger allocation control unit 25, and execute signal processing such as back diffusion and phase correction. The synthesis unit 22 inputs the signal processed by the finger unit 21 to perform rake synthesis.

The code generator 23 generates a channelization code and a scrambling code used for demodulation processing of the received signal by the receiving units 20a to 20c according to the control by the control unit 33, and outputs them to the receiving units 20a to 20c. The search unit 24 performs cell search and multipath detection from the digital signal converted by the A / D converter 19 under the control of the control unit 33, and outputs the detected results to the respective receiving units 20a to 20c. The finger assignment control unit 25 assigns the path of the channel to which the signal should be received to the finger unit 21.

The input memory 26 stores a signal rake-synthesized by the synthesis unit 22 of the reception units 20a to 20c. The decoding unit 27 performs decoding processing such as CRC check and turbo decoding of the data read from the input memory 26. The output memory 28 stores the data decoded by the decoding unit 27. As the memories 26 and 28, independent memories may be used for each receiving unit, or one large memory may be shared by the receiving units 20a to 20c.

The notification information receiving unit 29 reads necessary notification information from the decrypted data of BCH stored in the output memory 28 and outputs it to the protocol processing unit 8. The downlink individual channel receiving unit 30 and the downlink common channel receiving unit 31 output the decoded application data read from the output memory 28 to the application processing unit 7, and output the decoded control information data to the protocol processing unit 8. .. The selection unit 32 outputs the decoded data read from the output memory 28 to the downlink common channel reception unit 31 under the control of the control unit 33. The control unit 33 controls the processing by the above-described components 7 to 32. That is, in FIG. 3, only a part of the signal line from the control unit 33 to each component unit is shown, but the control unit 33 also controls the processing of the component unit that does not describe the signal line.

Here, a process of receiving data from the base station 2 by the mobile terminal 1 will be described. The weak signal received by the antenna 16 is amplified by the low noise amplification unit 17 and converted into a baseband signal by the frequency conversion unit 14. The A / D converter 19 converts an analog baseband signal into a digital signal and outputs it to the receiving units 20a to 20c and the search unit 24. The search unit 24 identifies the scrambling code of the base station 2 from the input digital signal and notifies the control unit 33 of the scrambling code, detects the path timing from the digital signal, and notifies the detected timings to the receiving units 20a to 20c and the receiving units 20a to 20c. Output to the finger assignment control unit 25. Further, the control unit 33 instructs which channel of which cell the receiving units 20a to 20c receive based on the information of the cell specified by the search unit 24.

The finger assignment control unit 33 selects a path that seems to be valid from a plurality of paths based on the search result by the search unit 24, and assigns the path to the finger unit 21. The code generator 23 generates a scrambling code corresponding to the base station 2 of each cell to receive the signal and a channelization code of the channel to receive the signal according to the control by the control unit 33, and receives the signal. Output to 20a ~ 20c.

The control unit 33 is at least one of the received powers such as the channel quality information (CQI information) of the uplink / downlink channel in the decoding unit 27, the error occurrence rate of CRC (Cyclic Redundancy Check), and the signal power to the interference wave reception power ratio. For example, by comparing these values with a predetermined threshold value, it is determined whether or not selective synthesis is performed. When performing selective synthesis, the control unit 33 controls the code generator 23 so that the reception units 20a to 20c receive the S-CCPCH for MBMS from different base stations 2.

In FIG. 3, the mobile terminal 1 has three systems of receiving units 20a to 20c. For example, the receiving unit 20a receives the S-CCPCH for control information, and the receiving unit 20b receives the S-CCPCH for MBMS. Receive. In addition, the receiving unit 20c receives the S-CCPCH for MBMS from another base station 2 for selective synthesis. The receiving units 20a to 20c can receive the signals of these channels at independent timings.

The finger units 21 of the receiving units 20a to 20c receive signals of each path assigned by the finger allocation control unit 25 based on the code input from the code generator 23, and perform signal processing such as back diffusion and phase correction. Is executed and output to the compositing unit 22. The synthesis unit 22 inputs the signal processed by the finger unit 21, rake synthesizes the signal, and stores the signal in the input memory 26.

The decoding unit 27 reads the received data from the receiving units 20a to 20c from the input memory 26, performs decoding processing such as a code with the CRC or turbo of the data, and writes the decoding result to the output memory 28. In general, one decoder hardware is often used in a time division manner due to the large circuit scale. However, when a plurality of decoders are implemented, it is also possible to assign a decoder to each cell or channel.

After that, necessary processing is performed for each channel, and the notification information receiving unit 29 obtains the necessary notification information from the BCH and passes it to the protocol processing unit 8. If the decoded data is application data, the downlink individual channel receiving unit 30 sends the data to the application processing unit 7, and if it is control information, sends the data to the protocol processing unit 8.

When performing selective synthesis, the selection unit 32 reads the S-CCPCH data for MBMS of different base stations 2 received by the reception units 20b and 20c from the output memory 28, respectively, and based on the CRC result in the decoding unit 27 and the like. The data that seems to be correct is output to the downlink common channel receiver 31, and the other data is discarded.

On the other hand, when selective composition is not performed, the selection unit 32 outputs the data received by the reception units 20b and 20c to the downlink common channel reception unit 31 without discarding the data. Similar to the downlink individual channel receiving unit 30, the downlink common channel receiving unit 31 outputs the received data to the application processing unit 7 if the received data is application data, and to the protocol processing unit 8 if the received data is control information. To do.

As described above, the S-CCPCH received by the receiving units 20a to 20c has S-CCPCH system information (Secondary CCPCH system information) and S-CCPCH information (Secondary CCPCH information), and is based on these information. The mobile terminal 1 can obtain information necessary for demodulation such as the diffusion rate, channelization code, and timing offset related to S-CCPCH. These parameters are received as control information by any of the broadcast information receiving unit 29, the downlink individual channel receiving unit 30, and the downlink common channel receiving unit 31, and are stored and managed in the protocol processing unit 8. The protocol processing unit 8 sets the above-mentioned parameters in the receiving units 20a to 20c, the code generator 23, the search unit 24, and the finger assignment control unit 25.

Mobile terminal 1 does not synthesize signals from different cells in order to receive control information S-CCPCH from only one active cell. At this time, the finger allocation control unit 25 allocates only the multipath component from one cell to the finger unit 21. Further, the control unit 33 observes a signal (radio wave) from the base station 2 in which the receiving units 20a to 20c have received the S-CCPCH signal, and requests transmission power increase / decrease according to the observation result. Information is transmitted to the protocol processing unit 8. The protocol processing unit 8 transmits the transmission power control information input from the control unit 33 to the base station 2 by using the uplink common channel transmission unit 9 or the uplink individual channel transmission unit 10.

Next, a base station (Node-B) constituting the mobile communication system according to the present invention will be described. FIG. 4 is a diagram showing the configuration of the base station in FIG. In FIG. 4, the base station 2 has a configuration of transmitting data to the mobile terminal 1 in addition to the antenna 42, such as a broadcast information transmission unit 34, a downlink individual channel transmission unit 35, a downlink common channel transmission unit 36, a modulation unit 37, and a downlink. It is provided with a code generator 38, a D / A converter 39, a frequency converter 40, and a power amplification unit 41. Further, as a configuration for receiving the signal from the mobile terminal 1, the low noise amplification unit 43, the frequency conversion unit 44, the A / D converter 45, the demodulation unit 46, the uplink code generator 47, the uplink individual channel receiver 48, and the uplink individual channel receiver 48 The uplink common channel receiver 49 is provided.

The notification information transmission unit 34 receives the notification information to be transmitted to the mobile terminal 1 via the base station control device 3, and performs coding processing as data to be carried on the P-CCPCH. The downlink individual channel transmission unit 35 is provided for each mobile terminal 1 that uses the individual channel, receives individual channel data and control information via the base station control device 3, and performs coding processing as data to be loaded on the DPCH. Further, the downlink common channel transmission unit 36 receives control information and multimedia data via the base station control device 3 and performs coding processing as data to be loaded on the S-CCPCH. Base station 2 may have one S-CCPCH or a plurality of S-CCPCHs.

In the present invention, an emergency information flag indicating the presence or absence of emergency information is newly provided in the MCCH transmitted through the S-CCPCH. When the downlink common channel transmission unit 36 receives multimedia data of emergency information via the base station control device 3, the downlink common channel transmission unit 36 sets a digital value indicating yes in the emergency information flag in MCCH. For example, when 1-bit digital data is set as the emergency information flag, the digital value 1 is set to have emergency information and the digital value 0 is set to no emergency information.

The modulation unit 37 inputs the data coded by the transmission units 34 to 36, and uses the channelization code and scrambling code set by the downlink code generator 38 to spread the data for each channel. The D / A converter 39 converts the digital data diffused by the modulation unit 37 into an analog signal. The frequency converter 40 converts the analog signal converted by the D / A converter 39 into an RF signal. The power amplification unit 41 amplifies the power of the RF signal converted by the frequency conversion unit 40. The power amplification unit 41 controls the amplification degree based on the transmission power control information received from the mobile terminal 1. The antenna 42 transmits the signal amplified by the power amplification unit 41 as a wireless signal, and also receives the signal from the mobile terminal 1.

The low noise amplification unit 43 amplifies the power of the weak signal received from the mobile terminal 1 via the antenna 42. The frequency conversion unit 44 converts the signal amplified by the low noise amplification unit 43 into a baseband signal. The A / D converter 45 converts the analog baseband signal input from the frequency converter 44 into a digital signal. The demodulation unit 46 separates the data from the mobile terminal 1 by using the scrambling code set by the uplink code generator 47, and separates each channel of the mobile terminal 1 by the channelization code. The uplink individual channel receiving unit 48 channel-decodes the signal of the individual channel demodulated by the demodulating unit 46, separates it, and transmits it to the base station control device 3. Further, the uplink common channel receiving unit 49 channel-decodes the signal of the common channel demodulated by the demodulating unit 46, separates the signal, and transmits the signal to the base station control device 3.

Next, the data transmission process to the mobile terminal 1 by the base station 2 will be described. Various control information and data to be transmitted to the mobile terminal 1 are received via the base station control device 3 and sent to transmission units 34 to 36 that transmit control information and data of each channel. The broadcast information coded as P-CCPCH data by the broadcast information transmission unit 34, the control information and data coded as DPCH data by the downlink individual channel transmission unit 35, and the S-CCPCH by the downlink common channel transmission unit 36. The control information and multimedia data coded as data are sent to the modulation unit 37. The modulation unit 37 uses the channelization code and scrambling code input from the downlink code generator 38 to spread the data input from the transmission units 34 to 36 for each channel and output it to the D / A converter 39. To do. The D / A converter 39 converts the digital signal input from the modulator 37 into an analog signal, and the frequency converter 40 further converts the analog signal converted by the D / A converter 39 into an RF signal. This RF signal is amplified to a desired power by the power amplification unit 41 and transmitted to the mobile terminal 1 as a radio signal via the antenna 42.

Subsequently, the data reception process from the mobile terminal 1 by the base station 2 will be described. The weak signal from the mobile terminal 1 received via the antenna 42 is amplified by the low noise amplification unit 43. The frequency conversion unit 44 converts the signal amplified by the low noise amplification unit 43 into a baseband signal, and the A / D converter 45 converts the baseband signal into a digital signal. The demodulation unit 46 separates the signal from each mobile terminal 1 in the cell managed by itself using the scrambling code set by the uplink code generator 47, and the channelization code set by the uplink code generator 47. Is used to separate each channel of mobile terminal 1. As for the signal demodulated by the demodulation unit 46, the signal of the individual channel is sent to the uplink individual channel reception unit 48, and the signal of the common channel is sent to the uplink common channel reception unit 49. The uplink individual channel receiver 48 and the uplink common channel receiver 49 channel-decode (decode) the input signal and transmit it to the base station control device 3.

Next, the base station control device 3 constituting the mobile communication system according to the present invention will be described. FIG. 5 is a diagram showing the configuration of the base station control device in FIG. In FIG. 5, the base station control device 3 relays between the processing of the core network and the radio line of the base station 2, mainly manages the radio resources, and instructs the base station 2 to establish and release the channel. It has a role and includes a transmission / reception processing unit 50, a base station transmission / reception processing unit 51, a QoS parameter mapping unit 52, a radio resource control unit 53, and a radio link control unit 54.

The transmission / reception processing unit 50 is a component that connects to the core network and other base station control devices 3, and is a core network such as RANAP (Radio Access Network Application Part) and other RNCs such as RNSAP (Radio Network Subsystem Application Part). Performs communication protocol processing to. The base station transmission / reception processing unit 51 performs communication protocol processing to base station 2 such as NBAP (Node B Application Part). The QoS parameter mapping unit 52 acquires the parameters of the radio channel that satisfies the request based on the QoS (Quality of Service) instruction from the core network.

The radio resource control unit 53 performs processing related to radio resources and notifies mobile terminal 1 of control information and parameters by RRC signaling. The wireless link control unit 54 performs buffering and retransmission control on the wireless link. It should be noted that the division of functions in these components is logical in terms of function, and is not always clearly separated in the actual implementation of hardware and software.

Next, the operation of the mobile communication system according to the first embodiment of the present invention will be described. FIG. 6 is a flowchart showing the notification processing of emergency information by the mobile communication system of the first embodiment, and the details of the operation will be described with reference to this figure. In the first embodiment, when the base station 2 transmits MBMS data that is not emergency information and the mobile terminal 1 receives the MBMS data that is not emergency information, the mobile terminal 1 is notified of the emergency information. To state.

First, the content provider transmits the multimedia data to the mobile terminal 1 to the service center 6. The service center 6 stores the multimedia data in the internal memory and transfers the multimedia data to the SGSN4 that manages the mobile terminal 1 that uses the multimedia service via the GGSN5. The SGSN4 transmits multimedia data to the base station 2 via the base station controller 3.

The base station 2 determines whether or not the multimedia data received from the base station controller 3 contains emergency information (step ST1). For example, the downlink common channel transmission unit 36 in the base station 2 determines the presence / absence of emergency information based on whether or not the multimedia data of emergency information has been received. The multimedia data of the emergency information transmitted to the base station 2 may be so-called wide area emergency information having the same contents among many base stations 2, or one or a small number of base stations 2. It may be so-called local emergency information that is closely related to the area where the contents are the same.

If it is determined in step ST1 that there is no emergency information, the process proceeds to step ST4. On the other hand, when it is determined that there is emergency information, the downlink common channel transmission unit 36 of the base station 2 sets "Yes" to the emergency information flag in the MCCH transmitted through the S-CCPCH that transmits the multimedia data of the emergency information. Set the indicated digital value (step ST2). For example, when the emergency information flag is set to 1-bit digital data, the digital value 1 is set to have emergency information, and the digital value 0 is set to no emergency information, the downlink common channel transmitter 36 changes the emergency information flag from the digital value 0 to 1. change.

Next, the base station 2 adds the information necessary for the mobile terminal 1 to receive the emergency information channel (hereinafter referred to as emergency information channel information) during the MCCH (step ST3). Here, as the emergency information channel information, for example, an emergency information channel number or the like can be considered. This emergency information channel information is added by the downlink common channel transmitter 36.

If the emergency information channel information is determined in advance by the mobile communication system and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, the base station 2 starts from. It is not necessary to notify the mobile terminal 1 of this information. In this case, step ST3 can be omitted. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

Further, when the emergency information channel information is determined by the base station 2, the base station 2 can omit step ST3 by notifying the mobile terminal 1 under its control in its own cell in advance. it can. For example, the broadcast information transmission unit 34 of the base station 2 notifies this information in advance using P-CCPCH as a part of the broadcast information. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

When it is determined in step ST1 that there is no emergency information, or when the processing in step ST3 is completed, the base station 2 transmits the MCCH to the mobile terminal 1 under its control (step ST4). When it is determined that there is emergency information, the downlink common channel transmitter 36 of the base station 2 maps the emergency information received via the base station controller 3 to the emergency information channel in MTCH (step ST5). ). After that, the base station 2 transmits MTCH to the mobile terminal 1 under the umbrella of receiving the MBMS in its own cell via the antenna 42 by the transmission process described above (step ST6). The order of the processes from step ST2 to step ST5 may be arbitrary, or these processes may be performed at the same time.

When the mobile terminal 1 receives the MCCH transmitted from the base station 2 (step ST7), the mobile terminal 1 determines the presence or absence of emergency information from the value of the emergency information flag in the MCCH (step ST8). For example, the content of the MCCH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 determines whether or not there is emergency information based on the value of the emergency information flag in the MCCH. Here, if it is determined from the value of the emergency information flag that there is no emergency information, the process returns to the process of step ST7.

If it is determined in step ST8 that there is emergency information, the mobile terminal 1 starts receiving the emergency information channel in MTCH according to the emergency information channel information in MCCH received in step ST7 (step ST9). In FIG. 3, the control unit 33 controls the code generator 23 and the finger assignment control unit 25 according to the emergency information channel information, and the reception unit 20b receives the emergency information channel in MTCH through the S-CCPCH for MBMS. ..

By providing an emergency information flag for setting the presence or absence of emergency information in the MCCH, the mobile terminal 1 receiving MBMS data can always monitor the emergency information flag by constantly receiving this MCCH, and the mobile terminal can monitor the emergency information flag. It is very effective for notifying the user of emergency information via 1.

If the emergency information channel information is determined in advance in the mobile communication system in step ST9, and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, According to this information, the mobile terminal 1 starts receiving the emergency information channel during MTCH. When the emergency information channel information is determined by the base station 2, the base station 2 uses P-CCPCH, for example, as a part of the notification information for the mobile terminal 1 under its control in its own cell. Notify in advance. In this case, the mobile terminal 1 can start receiving the emergency information channel during MTCH according to the emergency information channel information notified in advance.

In step ST9, when receiving the emergency information channel, the mobile terminal 1 may discard the information necessary for receiving the MBMS data (hereinafter referred to as the existing MBMS reception information) that has been received so far. Alternatively, it may be stored in the internal memory separately from the emergency information channel information. By saving the existing MBMS reception information separately from the emergency information channel information in this way, when the emergency situation is canceled and it is no longer necessary to receive the emergency information channel (or the emergency information channel from base station 2). If the transmission of MBMS is stopped), the existing MBMS reception information can be used to quickly return to the reception of MBMS data that had been received so far.

In step ST9, when receiving the emergency information channel, the mobile terminal 1 temporarily stops receiving the MBMS data that has been received so far. Here, if the wireless performance of the mobile terminal 1 is capable of receiving a plurality of MBMS data at the same time, the MBMS data that has been received up to that point may be received together with the data of the emergency information channel. In this case, the existing MBMS reception information needs to be saved separately from the emergency information channel information in the mobile terminal 1.

Furthermore, if the application performance as mobile terminal 1 can convey multiple MBMS data to the user at the same time, the MBMS data that has been received up to that point should be transmitted to the user together with the data of the emergency information channel. You may. Even in this case, the existing MBMS reception information needs to be saved in the mobile terminal 1 separately from the emergency information channel information.

As described above, according to the first embodiment, since the emergency information flag (emergency information indicator) indicating the presence or absence of emergency information is provided in the MCCH that can be monitored by the mobile terminal 1 corresponding to MBMS, it is not emergency information. Even if the mobile terminal 1 is receiving MBMS data, the presence or absence of emergency information can be checked periodically by the value of the emergency information flag in MCCH, and if it is determined that emergency information exists, it is in MBMS. Emergency information can be received via the emergency information channel, which is a channel.

In particular, since an emergency information flag (emergency information indicator) that can be represented by a small number of bits of digital data is provided in the MCCH as a configuration indicating the presence or absence of emergency information, in order to apply the first embodiment, the MCCH is provided. The amount of information to be added can be kept small.

In addition, since the mobile terminal 1 receives the emergency information data in the MBMS according to the value of the emergency information flag, it may receive other unnecessary information when receiving the emergency information, or the user may use the emergency information channel. Emergency information data in MBMS can be received at an early stage without the need for a selection action, and the breaking news of emergency information can be sufficiently ensured. Further, even when there is no emergency information, it is not necessary to receive other MCCH information, so that the power consumption of the mobile terminal 1 can be reduced.

In addition, in the first embodiment, both the emergency information flag and the emergency information channel information are provided in the MCCH. Therefore, as in Patent Document 1, when the information related to the emergency information is set as the notification information to be posted on the BCCH or the like, for example. It is possible to convey emergency information with a larger amount of information compared to.

Embodiment 2. The mobile communication system according to the second embodiment notifies the occurrence of emergency information even in a mobile terminal that is communicating individual data such as a voice call or a packet and does not receive MBMS data, and is urgent during MBMS. It enables reception of information channels.

The basic configuration of the mobile terminal, the base station, and the base station control device in the mobile communication system according to the second embodiment is the same as that of FIGS. 1 to 5 shown in the first embodiment, but the base station provides emergency information. When the occurrence occurs, MICH is sent to the mobile terminal prior to MCCH, and the mobile terminal that is communicating individual data such as voice calls and packets and does not receive MBMS data receives MCCH according to the contents of the MICH indicator. However, it differs in that the presence or absence of emergency information is determined by the value of the emergency information flag in MCCH and the emergency information is received by MBMS. Hereinafter, the configuration of the mobile communication system according to the second embodiment will also be described with reference to FIGS. 1 to 5.

In MICH, every time the base station 2 updates the MBMS channel information for the mobile terminal 1 that supports MBMS, and the MCCH (MBMS control information channel) content required for receiving MBMS data is updated. It is an indicator channel that is notified prior to MCCH to show the updated contents. In other words, mobile terminal 1 receives and monitors the contents of MICH even when MBMS data is not received, and the indicator contents of MICH indicate the service or service group that MBMS wants to receive. If so, you can start receiving MCCH and receive data for that service on MBMS.

In the second embodiment, even if the mobile terminal 1 is not receiving the MBMS service by a call or data communication, by monitoring the MICH, the indicator in the MICH shows the content including the emergency information. If so, start receiving MCCH. By detecting the emergency information flag provided in the MCCH by the mobile terminal 1, the presence or absence of emergency information is determined in the same manner as in the first embodiment. By performing these operations on a regular basis, the mobile terminal 1 that has not received MBMS can periodically check the presence or absence of emergency information, and the mobile terminal 1 that determines the existence of emergency information based on the value of the emergency information flag of MCCH. Can receive emergency information channels during MBMS.

Further, in the second embodiment, when the mobile terminal 1 recognizes the existence of emergency information during communication of individual data such as voice or packet, the user is notified of the occurrence of emergency information by vibration, icon blinking, character display, or the like. To do. As a result, it is possible to notify the user of the occurrence of emergency information without affecting packet communication such as calling or browsing the Web.

Next, the operation will be described. FIG. 7 is a flowchart showing the notification processing of emergency information by the mobile communication system of the second embodiment, and the details of the operation will be described with reference to this figure. In the second embodiment, a case where the base station 2 makes a voice call or data communication with the mobile terminal 1 and notifies the mobile terminal 1 of emergency information will be described.

First, the base station 2 communicates individual data such as voice and packets with the mobile terminal 1 using DTCH and DCCH mapped to DPCH (steps ST1a and ST9a). At this time, the content provider transmits the multimedia data to the mobile terminal 1 to the service center 6. The service center 6 stores the multimedia data in the internal memory and transfers the multimedia data to the SGSN4 that manages the mobile terminal 1 that uses the multimedia service via the GGSN5. The SGSN4 transmits multimedia data to the base station 2 via the base station controller 3.

Subsequently, the base station 2 determines whether or not there is emergency information in the multimedia data received from the base station control device 3 as in the first embodiment (step ST2a). For example, the downlink common channel transmission unit 36 of the base station 2 determines the presence or absence of emergency information based on whether or not the multimedia data of the emergency information has been received. The multimedia data of the emergency information transmitted to the base station 2 may be so-called wide area emergency information having the same contents among many base stations 2, or one or a small number of base stations 2. It may be so-called local emergency information that is closely related to the area where the contents are the same.

If it is determined in step ST2a that there is no emergency information, the process returns to step ST1a. On the other hand, when it is determined that there is emergency information, the downlink common channel transmission unit 36 of the base station 2 sets "Yes" to the emergency information flag in the MCCH transmitted through the S-CCPCH that transmits the multimedia data of the emergency information. Set the indicated digital value (step ST3a). For example, when the emergency information flag is set to 1-bit digital data, the digital value 1 is set to have emergency information, and the digital value 0 is set to no emergency information, the downlink common channel transmitter 36 changes the emergency information flag from the digital value 0 to 1. change.

Next, the base station 2 adds the information (emergency information channel information) necessary for the mobile terminal 1 to receive the emergency information channel during the MCCH (step ST4a). As the emergency information channel information, for example, an emergency information channel number or the like can be considered as in the first embodiment. This information is added by the downlink common channel transmitter 36.

If the emergency information channel information is determined in advance by the mobile communication system and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, the base station 2 starts from. It is not necessary to notify the mobile terminal 1 of this information. In this case, step ST4a can be omitted. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

Further, when the emergency information channel information is determined by the base station 2, the base station 2 can omit step ST4a by notifying the mobile terminal 1 under its control in its own cell in advance. it can. For example, the broadcast information transmission unit 34 of the base station 2 notifies this information in advance using P-CCPCH as a part of the broadcast information. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

The contents of MCCH are updated in step ST4a, or the processing of step ST4a is omitted as described above, the existence of emergency information is recognized in step ST2a, and the emergency information flag in MCCH is set to "" in step ST3a. When set to Yes, the base station 2 causes the digital value of the desired notification indicator of the MICH frame corresponding to all services or service groups to be changed. For example, when the notification indicator is 2-bit digital data, the digital value 11 has the MCCH change, and the digital value 00 has no MCCH change, the notification indicator is changed from the digital value 00 to 11. Base station 2 transmits MICH to its affiliated mobile terminal 1 (step ST5a). For example, when the downlink common channel transmission unit 36 of the base station 2 updates the MCCH in the process of the above-mentioned step, the MICH is transmitted to the mobile terminal 1 via the antenna 42 by the transmission process shown in the first embodiment. Send.

Subsequently, the base station 2 transmits the MCCH to the mobile terminal 1 under its control (step ST6a). When it is determined that there is emergency information, the downlink common channel transmitter 36 of the base station 2 maps the emergency information received via the base station controller 3 to the emergency information channel in MTCH (step ST7a). ). After that, the base station 2 transmits MTCH to the mobile terminal 1 under its umbrella that receives the MBMS in its own cell via the antenna 42 by the transmission process described above (step ST8a). The processing order of steps ST3a and ST4a may be arbitrary, or these processes may be performed at the same time.

In step ST9a, the mobile terminal 1 transmits / receives individual data such as voice and packets to / from the base station 2. At this time, when the mobile terminal 1 receives the MICH transmitted from the base station 2 as described above (step ST10a), the indicator in this MICH indicates the MBMS reception target content of the mobile terminal 1 including the emergency information channel. It is determined whether or not it is a thing (step ST11a). For example, the content of the MICH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 changes the MCCH of the MBMS reception target of the mobile terminal 1 including the emergency information channel based on the content of the indicator in the MICH. It is determined whether or not it is indicated. Here, if it is determined that the MCCH change of the MBMS reception target of the mobile terminal 1 including the emergency information channel is not indicated, the process returns to the process of step ST9a.

Further, when it is determined in step ST11a that the content of the MBMS reception target of the mobile terminal 1 including the emergency information channel is indicated, the mobile terminal 1 receives the MCCH transmitted from the base station 2 as described above ( Step ST12a), and determine the presence or absence of emergency information from the value of the emergency information flag in this MCCH (step ST13a). For example, the content of the MCCH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 determines whether or not there is emergency information based on the value of the emergency information flag in the MCCH. Here, if it is determined from the value of the emergency information flag that there is no emergency information, the process returns to the process of step ST9a.

Further, when it is determined in step ST13a that there is emergency information, the mobile terminal 1 follows the emergency information channel information in MCCH received in step ST12a, and the emergency in MTCH transmitted from the base station 2 as described above. Start receiving the information channel (step ST14a).

If the emergency information channel information is determined in advance in the mobile communication system in step ST14a, and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, According to this information, the mobile terminal 1 starts receiving the emergency information channel during MTCH. When the emergency information channel information is determined by the base station 2, the base station 2 uses P-CCPCH, for example, as a part of the notification information for the mobile terminal 1 under its control in its own cell. Notify in advance. In this case, the mobile terminal 1 can start receiving the emergency information channel during MTCH according to the emergency information channel information notified in advance.

In this way, even the mobile terminal 1 that communicates individual data such as voice and packets with the base station 2 and does not receive MBMS data receives MICH, and this MICH indicator. Indicates the MBMS reception target content including the emergency information channel, MCCH reception is started, and the presence or absence of emergency information can be recognized by the value of the emergency information flag. Therefore, the mobile terminal 1 receives the MBMS data. It is possible to monitor the presence or absence of emergency information from the base station 2 even when it is not received or regardless of which service is selected, and it is extremely possible to notify the user of emergency information via the mobile terminal 1. It is effective for.

When the mobile terminal 1 starts receiving the emergency information channel, it notifies the user that it has started receiving emergency information by displaying sound, vibration, and characters on the screen of the display device (step ST15a). For example, even during a call or packet communication, the control unit 33 controls a voice output unit (not shown), a vibration mechanism, and a display processing unit according to the start of reception of the emergency information channel, as described above. Notify emergency information.

As described above, according to the second embodiment, the base station 2 transmits the MICH to the mobile terminal 1 prior to the MCCH, the mobile terminal 1 receives the MCCH according to the contents of the MICH indicator, and the MCCH is in progress. Since the presence or absence of emergency information is determined by the value of the emergency information flag of and the emergency information is received by MBMS, even if the mobile terminal 1 is not receiving MBMS data during individual data communication such as voice call or packet, It is possible to notify the occurrence of emergency information and receive the emergency information channel in MBMS. In addition, the user of the mobile terminal 1 during individual data communication can be notified of the emergency information received on the emergency channel in MBMS.

Embodiment 3. The mobile communication system according to the third embodiment notifies the occurrence of emergency information and enables reception of the emergency information channel during MBMS even if the mobile terminal is not receiving MBMS data in the standby state. Is.

The basic configuration of the mobile terminal, the base station, and the base station control device in the mobile communication system according to the third embodiment is the same as that of FIGS. 1 to 5 shown in the first embodiment, but the base station provides emergency information. When the occurrence occurs, MICH is sent to the mobile terminal prior to MCCH, and the mobile terminal that has not received MBMS data in the standby state receives MCCH according to the contents of the MICH indicator, and the emergency information flag in MCCH is displayed. The difference is that the value determines the presence or absence of emergency information and the MBMS receives the emergency information. Hereinafter, the configuration of the mobile communication system according to the third embodiment will also be described with reference to FIGS. 1 to 5.

As shown in the second embodiment, in the MICH, the base station 2 updates the MBMS channel information for the mobile terminal 1 that supports MBMS, and the MCCH (MBMS control) required for receiving the MBMS data. This is an indicator channel that is notified prior to MCCH to indicate the updated content each time the content of the information channel) is updated. In other words, mobile terminal 1 receives and monitors the contents of MICH even when MBMS data is not received, and the indicator contents of MICH indicate the service or service group that MBMS wants to receive. If so, you can start receiving MCCH and receive data for that service on MBMS.

In the third embodiment, even if the mobile terminal 1 is in the standby state and does not receive the MBMS service, by monitoring the MICH, when the indicator in the MICH indicates the content including the emergency information, the MCCH Start receiving. By detecting the emergency information flag provided in the MCCH by the mobile terminal 1, the presence or absence of emergency information is determined in the same manner as in the first embodiment. By performing these operations on a regular basis, the mobile terminal 1 that has not received MBMS can periodically check the presence or absence of emergency information, and the mobile terminal 1 that determines the existence of emergency information based on the value of the emergency information flag of MCCH. Can receive emergency information channels during MBMS.

Further, in the third embodiment, as in the second embodiment, when the mobile terminal 1 recognizes the existence of emergency information during communication of individual data such as voice and packets, vibration, icon blinking, character display, etc. Notifies the user of the occurrence of emergency information. As a result, it is possible to notify the user of the occurrence of emergency information without affecting packet communication such as calling or browsing the Web.

Next, the operation will be described. FIG. 8 is a flowchart showing the notification processing of emergency information by the mobile communication system of the third embodiment, and the details of the operation will be described with reference to this figure. In the third embodiment, the case where the emergency information is notified to the mobile terminal 1 which is in the standby state and has not received the MBMS data will be described.

First, when the mobile terminal 1 is in the standby state, the base station 2 periodically transmits PICH to the mobile terminal 1 under its control in its own cell (step ST1b). At this time, the content provider transmits the multimedia data to the mobile terminal 1 to the service center 6. The service center 6 stores the multimedia data in the internal memory and transfers the multimedia data to the SGSN4 that manages the mobile terminal 1 that uses the multimedia service via the GGSN5. The SGSN4 transmits multimedia data to the base station 2 via the base station controller 3.

Subsequently, the base station 2 determines whether or not there is emergency information in the multimedia data received from the base station control device 3 as in the first embodiment (step ST2b). For example, the downlink common channel transmission unit 36 in the base station 2 determines the presence / absence of emergency information based on whether or not the multimedia data of emergency information has been received. The multimedia data of the emergency information transmitted to the base station 2 may be so-called wide area emergency information having the same contents among many base stations 2, or one or a small number of base stations 2. It may be so-called local emergency information that is closely related to the area where the contents are the same.

If it is determined in step ST2b that there is no emergency information, the process returns to step ST1b. On the other hand, when it is determined that there is emergency information, the downlink common channel transmission unit 36 of the base station 2 sets "Yes" to the emergency information flag in the MCCH transmitted through the S-CCPCH that transmits the multimedia data of the emergency information. Set the indicated digital value (step ST3b). For example, when the emergency information flag is set to 1-bit digital data, the digital value 1 is set to have emergency information, and the digital value 0 is set to no emergency information, the downlink common channel transmitter 36 changes the emergency information flag from the digital value 0 to 1. change.

Next, the base station 2 adds the information (emergency information channel information) necessary for the mobile terminal 1 to receive the emergency information channel during MCCH (step ST4b). As the emergency information channel information, for example, an emergency information channel number or the like can be considered as in the first embodiment. This information is added by the downlink common channel transmitter 36.

If the emergency information channel information is determined in advance by the mobile communication system and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, the base station 2 starts from. It is not necessary to notify the mobile terminal 1 of this information. In this case, step ST4b can be omitted. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

Further, when the emergency information channel information is determined by the base station 2, the base station 2 can omit step ST4b by notifying the mobile terminal 1 under its control in its own cell in advance. it can. For example, the broadcast information transmission unit 34 of the base station 2 notifies this information in advance using P-CCPCH as a part of the broadcast information. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

The contents of MCCH are updated in step ST4b, or the processing of step ST4b is omitted as described above, the existence of emergency information is recognized in step ST2b, and the emergency information flag in MCCH is set to "" in step ST3b. When set to Yes, the base station 2 causes the digital value of the desired notification indicator of the MICH frame corresponding to all services or service groups to be changed. For example, when the notification indicator is 2-bit digital data, the digital value 11 has the MCCH change, and the digital value 00 has no MCCH change, the notification indicator is changed from the digital value 00 to 11. Base station 2 transmits MICH to its affiliated mobile terminal 1 (step ST5b). For example, when the downlink common channel transmission unit 36 of the base station 2 updates the MCCH in the process of the above-mentioned step, the MICH is transmitted to the mobile terminal 1 via the antenna 42 by the transmission process shown in the first embodiment. Send.

Subsequently, the base station 2 transmits the MCCH to the mobile terminal 1 under its control (step ST6b). When it is determined that there is emergency information, the downlink common channel transmitter 36 of the base station 2 maps the emergency information received via the base station controller 3 to the emergency information channel in MTCH (step ST7b). ). After that, the base station 2 transmits MTCH to the mobile terminal 1 under the umbrella of receiving the MBMS in its own cell via the antenna 42 by the transmission process described above (step ST8b). The processing order of steps ST3b and ST4b may be arbitrary, or these processes may be performed at the same time.

In step ST9b, the mobile terminal 1 receives the PICH from the base station 2 and determines the presence or absence of information (PI; Paging Indicator) for its own station (own terminal). For example, the content of PICH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 determines whether or not there is information for its own station by the PICH. At this time, if it is determined that there is information for the own station, the mobile terminal 1 starts receiving S-CCPCH from the base station 2 based on the information for the own station (step ST10b).

On the other hand, if it is determined that there is no information for its own station, the mobile terminal 1 receives the MICH transmitted from the base station 2 as described above (step ST11b), and the indicator in this MICH is an emergency information channel. It is determined whether or not the content of the MBMS reception target of the mobile terminal 1 including the above is indicated (step ST12b). For example, the content of the MICH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 changes the MCCH of the MBMS reception target of the mobile terminal 1 including the emergency information channel based on the content of the indicator in the MICH. It is determined whether or not it is indicated. Here, if it is determined that the MCCH change of the MBMS reception target of the mobile terminal 1 including the emergency information channel is not indicated, the process returns to the process of step ST9b.

Further, if it is determined in step ST12b that the content of the MBMS reception target of the mobile terminal 1 including the emergency information channel is indicated, the mobile terminal 1 receives the MCCH transmitted from the base station 2 as described above. (Step ST13b), and determine the presence or absence of emergency information from the value of the emergency information flag in this MCCH (step ST14b). For example, the content of the MCCH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 determines whether or not there is emergency information based on the value of the emergency information flag in the MCCH. Here, if it is determined from the value of the emergency information flag that there is no emergency information, the process returns to the process of step ST9b.

Further, when it is determined in step ST14b that there is emergency information, the mobile terminal 1 follows the emergency information channel information in MCCH received in step ST13b, and the emergency in MTCH transmitted from the base station 2 as described above. Start receiving the information channel (step ST15b).

If the emergency information channel information is determined in advance in the mobile communication system in step ST15b, and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, According to this information, the mobile terminal 1 starts receiving the emergency information channel during MTCH. When the emergency information channel information is determined by the base station 2, the base station 2 uses P-CCPCH, for example, as a part of the notification information for the mobile terminal 1 under its control in its own cell. Notify in advance. In this case, the mobile terminal 1 can start receiving the emergency information channel during MTCH according to the emergency information channel information notified in advance.

In this way, even the mobile terminal 1 that is in the standby state and does not receive MBMS data is set to receive MICH, and the indicator of this MICH indicates the MBMS reception target content including the emergency information channel. , MCCH reception is started and the presence / absence of emergency information can be recognized by the value of the emergency information flag, so even if mobile terminal 1 is not receiving MBMS data, or which service is selected. However, it is possible to monitor the presence or absence of emergency information from the base station 2, which is very effective for notifying the user of emergency information via the mobile terminal 1.

When the mobile terminal 1 starts receiving the emergency information channel, it notifies the user that it has started receiving emergency information by displaying sound, vibration, and characters on the screen of the display device (step ST16b). For example, even during a call or packet communication, the control unit 33 controls a voice output unit (not shown), a vibration mechanism, and a display processing unit according to the start of reception of the emergency information channel, as described above. Notify emergency information.

As described above, according to the third embodiment, the base station 2 transmits the MICH to the mobile terminal 1 prior to the MCCH, the mobile terminal 1 receives the MCCH according to the contents of the MICH indicator, and the MCCH is in progress. Since the presence or absence of emergency information is determined by the value of the emergency information flag of and the emergency information is received by MBMS, even if the mobile terminal 1 is in the standby state and does not receive MBMS data, the occurrence of emergency information is notified. , Can receive emergency information channels during MBMS. In addition, the user of the mobile terminal 1 during individual data communication can be notified of the emergency information received on the emergency channel in MBMS.

In the above embodiments 2 and 3, as a method of indicating that the indicator in MICH includes the content including emergency information, when the emergency information flag in MCCH is set to "Yes", all services or service groups are affected. It was decided to change the digital value of the desired notification indicator of the corresponding MICH frame. Alternatively, an indicator dedicated to the MCCH emergency information flag change notification may be provided in all MICH frames. In this case, if the emergency information flag in MCCH is set to "Yes" in steps ST3a and ST3b, the base station 2 is dedicated to the notification of change of the emergency information flag in MCCH of the MICH frame corresponding to all services or service groups. Change the digital value of the indicator. For example, if the indicator dedicated to the emergency information flag change notification during MCCH is 2-bit digital data, the digital value 11 is changed to MCCH, and the digital value 00 is not changed to MCCH, the notification indicator is changed from digital value 00 to 11. .. In steps ST11a and ST12b, the mobile terminal 1 receives the MICH frame corresponding to the service to be received, determines the MCCH change by the desired indicator, and monitors the MCCH emergency information flag change notification dedicated indicator in the same MICH frame. However, it is also necessary to judge whether the emergency information flag in MCCH is set to "Yes". The indicator dedicated to the emergency information flag change notification during MCCH may be digital data having the same number of bits as other notification indicators. As described above, by providing an indicator dedicated to the MCCH emergency information flag change notification in all MICH frames, mobile terminals that do not normally (non-emergency) want to receive services or service groups can also be urgent during MCCH. By receiving only the information flag change notification indicator, it is possible to determine whether or not the MCCH emergency information flag in case of emergency is set to "Yes". In addition, since an indicator dedicated to the MCCH emergency information flag change notification is provided in all MICH frames, the mobile terminal may receive any MICH frame, and flexible scheduling should be performed between the base station and the mobile terminal. Is possible.

Alternatively, a service or service group dedicated to the MCCH emergency information channel may be set up. In this case, if the emergency information flag in MCCH is set to "Yes" in steps ST3a and ST3b, the base station 2 will perform the emergency information in MCCH of the MICH frame corresponding to the service or service group dedicated to the MCCH emergency information channel. Flag Change the digital value of the indicator for change notification. For example, if the emergency information flag change notification indicator during MCCH is 2-bit digital data, the digital value 11 is changed to MCCH, and the digital value 00 is not changed to MCCH, the notification indicator is changed from digital value 00 to 11. .. In steps ST11a and ST12b , the mobile terminal 1 sets the emergency information flag in MCCH to "Yes" by the indicator for changing the emergency information flag in MCCH in the MICH frame corresponding to the service or service group dedicated to the MCCH emergency information channel. Try to determine if it has been done. The MCCH emergency information flag change notification indicator may be digital data having the same number of bits as the other service or service group notification indicator. As described above, by setting the service or service group dedicated to the MCCH emergency information channel, the mobile terminal when there is no service or service group that you normally want to receive (not urgent) can also be the service dedicated to the emergency information channel during MCCH. Alternatively, by receiving only the MICH frame corresponding to the service group, it is possible to determine whether or not the MCCH emergency information flag in the case of an emergency in the frame is set to "Yes". ..

In the above embodiments 2 and 3, the case where the mobile terminal is in individual data communication (CELL_DCH state) or standby (Idle state) is disclosed, but an emergency information flag is provided in MCCH and the mobile terminal sets MICH. The method of receiving, receiving the MCCH according to the content of the indicator, determining the presence or absence of the emergency information by the value of the emergency information flag in the MCCH, and receiving the emergency information by MBMS is not limited to the above state, but is CELL_FACH. Since it can be applied to the state, CELL_PCH state, and URA_PCH state, it is possible to receive emergency information data regardless of the possible state of the mobile terminal, and receive other unnecessary information when receiving emergency information. It is possible to receive the emergency information data in the MBMS at an early stage without requiring the operation of selecting the emergency information channel on the user side, and it is possible to sufficiently secure the promptness of the emergency information.

Although the mobile terminal receives MICH and receives MCCH according to the content of the indicator in the above-described second and third embodiments, PICH may be used instead of MICH. Specifically, an indicator dedicated to the MCCH emergency information flag change notification may be provided in all PICH frames. In this case, if the emergency information flag in MCCH is set to "Yes" in steps ST3a and ST3b, the base station 2 changes the emergency information flag in MCCH of the PICH frame corresponding to all mobile terminals or mobile terminal groups. Change the digital value of the notification-only indicator. For example, if the indicator dedicated to the emergency information flag change notification during MCCH is 2-bit digital data, the digital value 11 is changed to MCCH, and the digital value 00 is not changed to MCCH, the notification indicator is changed from digital value 00 to 11. .. In steps ST11a and ST12b, the mobile terminal 1 receives the PICH frame corresponding to the own mobile terminal, monitors the MCCH emergency information flag change notification dedicated indicator in the PICH frame, and sets the emergency information flag in the MCCH to "Yes". Try to determine if it is set to. The indicator dedicated to the emergency information flag change notification during MCCH may be digital data having the same number of bits as other indicators (paging indicators) in the PICH frame. The mobile terminal determined to be "Yes" in steps ST11a and ST12b should immediately shift to the operation of receiving MCCH in steps ST12a and ST13b.

Alternatively, a PICH frame dedicated to the MCCH emergency information channel may be set. In this case, when the emergency information flag in MCCH is set to "Yes" in steps ST3a and ST3b, the base station 2 digitally indicates the emergency information flag change notification in MCCH of the PICH frame dedicated to the MCCH emergency information channel. Let the value change. For example, if the emergency information flag change notification indicator during MCCH is 2-bit digital data, the digital value 11 is changed to MCCH, and the digital value 00 is not changed to MCCH, the notification indicator is changed from digital value 00 to 11. .. In steps ST11a and ST12b, the mobile terminal 1 determines whether or not the emergency information flag in MCCH is set to "Yes" by the indicator for notification of change of the emergency information flag in MCCH in the PICH frame dedicated to the MCCH emergency information channel. Leave it to. The mobile terminal determined to be "Yes" in steps ST11a and ST12b should immediately shift to the operation of receiving MCCH in steps ST12a and ST13b. Normally, PICH is received when the mobile terminal is waiting (Idle state), but not limited to that state, the mobile terminal should also receive PICH in the CELL_DCH state, CELL_FACH state, CELL_PCH state, and URA_PCH state. Therefore, emergency information data can be received regardless of the possible state of the mobile terminal, and when receiving emergency information, it is necessary to receive other unnecessary information such as BCCH, or to select an emergency information channel on the user side. It is possible to receive the emergency information data in the MBMS at an early stage without having to do so, and it is possible to sufficiently secure the promptness of the emergency information.

In the above-described first to third embodiments, when the base station 2 determines whether or not the multimedia data received from the base station control device 3 has emergency information, and determines that the emergency information exists. , Sending multimedia data of emergency information To set the emergency information flag in MCCH transmitted through S-CCPCH to a digital value indicating "Yes", and the mobile terminal 1 receives the emergency information channel during MCCH. The necessary information (emergency information channel information) was added and the emergency information was mapped to the emergency information channel in MTCH, but the base station controller 3 may perform these processes.

A specific example is shown. The base station controller 3 to which the multimedia data is transmitted from the SGSN4 determines in steps ST1, ST2a, and ST2b whether or not there is emergency information in the multimedia data. For example, the radio resource control unit 53 of the base station control device 3 determines the presence or absence of emergency information based on whether or not the multimedia data of the emergency information has been received. If the base station controller 3 determines that there is no emergency information, the process proceeds to steps ST4, ST5a, and ST5b. On the other hand, when it is determined that there is emergency information, the radio resource control unit 53 of the base station control device 3 sets the emergency information flag in the MCCH transmitted through the S-CCPCH that transmits multimedia data of the emergency information to "Yes". Set the digital values that indicate (steps ST2, ST3a, ST3b). For example, when the emergency information flag is set to 1-bit digital data, the digital value 1 is set to have emergency information, and the digital value 0 is set to no emergency information, the radio resource control unit 53 changes the emergency information flag from the digital value 0 to 1. To do.

The base station controller 3 then adds emergency information channel information during the MCCH (steps ST3, ST4a, ST4b). Here, as the emergency information channel information, for example, an emergency information channel number or the like can be considered. This emergency information channel information is added by the radio resource control unit 53. If the emergency information channel information is determined in advance by the mobile communication system and both the mobile terminal 1 and the base station control device 3 in the mobile communication system recognize this information, the base station It is not necessary to notify the mobile terminal 1 of this information from the control device via the base station 2. In this case, steps ST3, ST4a and ST4b can be omitted. By doing so, the processing load in the base station control device 3 can be reduced, and the radio resources can be effectively utilized for other processing. Further, when the emergency information channel information is determined by the base station control device 3, the base station control device 3 passes through the base station 2 to the mobile terminal 1 under the umbrella in the cell of the base station 2 in advance. By notifying, step ST3 can be omitted. For example, the broadcast information transmission unit 34 of the base station 2 notifies this information in advance using P-CCPCH as a part of the broadcast information. By doing so, the processing load in the base station control device 3 can be reduced, and the radio resources can be effectively utilized for other processing.

When it is determined that there is no emergency information in steps ST1, ST2a, and ST2b, or when the processing of steps ST3, ST4a, and ST4b is completed, the base station controller 3 transfers the MCCH to the mobile terminal 1 under the control of the base station 2. Send to (steps ST4, ST6a, ST6b). When it is determined that there is emergency information, the radio resource control unit 53 of the base station controller 3 maps the emergency information to the emergency information channel in MTCH (steps ST5, ST7a, ST7b). After that, the base station control device 3 transmits MTCH via the base station 2 to the mobile terminal 1 under the umbrella of receiving the MBMS in its own cell via the antenna 42 by the transmission process of the base station 2 described above (the above-mentioned transmission process of the base station 2). Steps ST6, ST8a, ST8b). The order of these processes may be arbitrary, or these processes may be performed at the same time.

As described above, the base station control device 3 determines whether or not the received multimedia data has emergency information, and if it determines that there is emergency information, the multimedia data of the emergency information is transmitted through S-CCPCH. Set the emergency information flag in the transmitted MCCH to a digital value indicating "Yes", and then add the information (emergency information channel information) required for the mobile terminal 1 to receive the emergency information channel during the MCCH. Since the processing is performed, it is possible for each base station 2 to transmit the so-called wide area emergency information of the same content from a plurality of base stations 2 without performing the above processing, and the mobile terminal at the cell end can be used. The reception power from the plurality of base stations 2 can be combined, the reception quality can be improved, and emergency information can be transmitted quickly and accurately.

Embodiment 4. In the fourth embodiment, the emergency information flag provided in BCCH is used to notify the occurrence of emergency information even in a mobile terminal receiving individual data that is not emergency information, and the emergency information channel in MBMS. It enables the reception of.

The basic configuration of the mobile terminal, the base station, and the base station control device in the mobile communication system according to the fourth embodiment is the same as that of FIGS. 1 to 5 shown in the first embodiment, but with the broadcast information control channel. An emergency information flag (emergency information indicator) indicating the presence or absence of emergency information is provided in a certain BCCH, and when the base station generates emergency information, the BCCH is transmitted to the mobile terminal and the mobile terminal receiving individual data that is not emergency information. However, it differs in that the presence or absence of emergency information is determined by the value of the emergency information flag in BCCH and the emergency information is received by MBMS. Hereinafter, the configuration of the mobile communication system according to the fourth embodiment will also be described with reference to FIGS. 1 to 5.

Next, the operation will be described. FIG. 9 is a flowchart showing the notification processing of emergency information by the mobile communication system of the fourth embodiment, and the details of the operation will be described with reference to this figure. In the fourth embodiment, a case where the base station 2 is transmitting individual data that is not emergency information to the mobile terminal 1 and the mobile terminal 1 is notified of the emergency information will be described.

First, the content provider transmits the multimedia data to the mobile terminal 1 to the service center 6. The service center 6 stores the multimedia data in the internal memory and transfers the multimedia data to the SGSN4 that manages the mobile terminal 1 that uses the multimedia service via the GGSN5. The SGSN4 transmits multimedia data to the base station 2 via the base station controller 3.

The base station 2 determines whether or not there is emergency information in the multimedia data received from the base station control device 3 as in the first embodiment (step ST1c). For example, the downlink common channel transmission unit 36 of the base station 2 determines the presence or absence of emergency information based on whether or not the multimedia data of the emergency information has been received. The multimedia data of the emergency information transmitted to the base station 2 may be so-called wide area emergency information having the same contents among many base stations 2, or one or a small number of base stations 2. It may be so-called local emergency information that is closely related to the area where the contents are the same.

If it is determined in step ST1c that there is no emergency information, the process proceeds to step ST4c. On the other hand, when it is determined that there is emergency information, the downlink common channel transmission unit 36 of the base station 2 sets "Yes" to the emergency information flag in BCCH transmitted through S-CCPCH which transmits multimedia data of emergency information. Set the indicated digital value (step ST2c). For example, when the emergency information flag is set to 1-bit digital data, the digital value 1 is set to have emergency information, and the digital value 0 is set to no emergency information, the downlink common channel transmitter 36 changes the emergency information flag from the digital value 0 to 1. change.

Next, base station 2 adds BCCH Modify information to PAGING TYPE 2 in DCCH (step ST3c). BCCH Modify information indicates the changed contents when the contents of BCCH are changed. This information is added by the downlink individual channel transmitter 35 or the downlink common channel transmitter 36.

Subsequently, the base station 2 transmits the DCCH to the mobile terminal 1 under its control (step ST4c). After that, the base station 2 adds the information (emergency information channel information) necessary for the mobile terminal 1 to receive the emergency information channel during the MCCH (step ST5c). As the emergency information channel information, for example, an emergency information channel number or the like can be considered as in the first embodiment. This information is added by the downlink common channel transmitter 36.

If the emergency information channel information is determined in advance by the mobile communication system and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, the base station 2 starts from. It is not necessary to notify the mobile terminal 1 of this information. In this case, step ST5c can be omitted. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

Further, when the emergency information channel information is determined by the base station 2, the base station 2 can omit step ST5c by notifying the mobile terminal 1 under its control in its own cell in advance. it can. For example, the broadcast information transmission unit 34 of the base station 2 notifies this information in advance using P-CCPCH as a part of the broadcast information. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

Next, the base station 2 transmits the MCCH to the mobile terminal 1 under its control (step ST6c). When it is determined that there is emergency information, the downlink common channel transmitter 36 of the base station 2 maps the emergency information received via the base station controller 3 to the emergency information channel in MTCH (step ST7c). ). After that, the base station 2 transmits MTCH to the mobile terminal 1 under the umbrella of receiving the MBMS in its own cell via the antenna 42 by the transmission process described above (step ST8c). The processing order from step ST2c to step ST7c may be arbitrary, or these processes may be performed at the same time.

The mobile terminal 1 receives the DCCH transmitted from the base station 2 as described above (step ST9c), and determines whether or not the PAGING TYPE 2 in the DCCH has BCCH Modify information (step ST10c). For example, the contents of the DCCH received by the mobile terminal 1 are sent to the control unit 33, and the control unit 33 analyzes the contents of the PAGING TYPE 2 in the DCCH to determine the presence or absence of BCCH Modify information. Here, if it is determined that there is no BCCH Modify information, the process returns to the process of step ST9c.

On the other hand, if it is determined in step ST10c that there is BCCH Modify information, mobile terminal 1 receives BCCH from base station 2 (step ST11c) and determines the presence or absence of emergency information from the value of the emergency information flag in this BCCH. (Step ST12c). For example, the content of BCCH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 determines the presence or absence of emergency information based on the value of the emergency information flag in BCCH. Here, if it is determined from the value of the emergency information flag that there is no emergency information, the mobile terminal 1 shifts to the process of step ST15c, executes the normal BCCH update process, and then returns to the process of step ST9c. ..

When it is determined in step ST12c that there is emergency information, the mobile terminal 1 receives the MCCH transmitted from the base station 2 as described above (step ST13c), and the base station according to the emergency information channel information in the MCCH. Start receiving the emergency information channel in MTCH sent from 2 (step ST14c).

If the emergency information channel information is determined in advance in the mobile communication system in step ST14c, and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, According to this information, the mobile terminal 1 starts receiving the emergency information channel during MTCH.

When the emergency information channel information is determined by the base station 2, the base station 2 uses P-CCPCH, for example, as a part of the notification information for the mobile terminal 1 under its control in its own cell. Notify in advance. In this case, the mobile terminal 1 can start receiving the emergency information channel during MTCH according to the emergency information channel information notified in advance.

As described above, according to the fourth embodiment, since the emergency information flag (emergency information indicator) indicating the presence or absence of emergency information is provided in BCCH, the mobile terminal 1 receiving individual data that is not emergency information Even if there is, BCCH can notify the occurrence of emergency information and receive the emergency information channel in MBMS. Also, unlike the case where an emergency information flag is set for MCCH that can be received only by mobile terminal 1 that supports MBMS, BCCH can be received even by mobile terminal 1 that does not support MBMS, so it is a base station. 2 can notify all mobile terminals 1 in its own cell of the presence or absence of emergency information.

In Patent Document 1, in addition to the information indicating the presence or absence of emergency information, the emergency information channel information, which is the information necessary for receiving the emergency information channel, is transmitted as, for example, BCCH notification information. The amount of information becomes large, and it may be necessary to reduce other information transmitted as broadcast information. On the other hand, in the fourth embodiment, since only the emergency information flag (emergency information indicator) indicating the presence or absence of emergency information is provided in the BCCH, the minimum required to notify the presence or absence of emergency information is provided. The amount of information is sufficient, and there is no need to reduce other information in BCCH. In addition, since the mobile terminal 1 does not have to receive information unnecessary for receiving emergency information via BCCH and can receive emergency information data in MBMS at an early stage, it is possible to ensure breaking news of emergency information. it can.

Embodiment 5. In the fifth embodiment, the emergency information flag provided in BCCH is used to notify the occurrence of emergency information even in a mobile terminal that has not received MBMS data in the standby state, and the emergency information in MBMS. It enables reception of channels.

The basic configuration of the mobile terminal, the base station, and the base station control device in the mobile communication system according to the fifth embodiment is the same as that of FIGS. 1 to 5 shown in the first embodiment, but with the broadcast information control channel. An emergency information flag (emergency information indicator) is provided to indicate the presence or absence of emergency information in a certain BCCH, and when the base station generates emergency information, the BCCH is sent to the mobile terminal and the MBMS data is not received in the standby state. The difference is that the terminal determines the presence or absence of emergency information based on the value of the emergency information flag in BCCH and receives the emergency information by MBMS. Hereinafter, the configuration of the mobile communication system according to the fifth embodiment will also be described with reference to FIGS. 1 to 5.

Next, the operation will be described. FIG. 10 is a flowchart showing the notification processing of emergency information by the mobile communication system of the fifth embodiment, and the details of the operation will be described with reference to this figure. In the fifth embodiment, the case where the emergency information is notified to the mobile terminal 1 which is in the standby state and has not received the MBMS data will be described.

First, the base station 2 is periodically transmitting PICH to the mobile terminal 1 under its control in its own cell, and the mobile terminal 1 is in the standby state until the information for its own station is received by the PICH. is there. At this time, when the content provider transmits the multimedia data to the mobile terminal 1 to the service center 6, the service center 6 stores the multimedia data in the internal memory and transmits the multimedia service via the GGSN5. Transfer to SGSN4, which manages the mobile terminal 1 to be used. The SGSN4 transmits multimedia data to the base station 2 via the base station controller 3.

The base station 2 determines whether or not there is emergency information in the multimedia data received from the base station control device 3 as in the first embodiment (step ST1d). For example, the downlink common channel transmission unit 36 of the base station 2 determines the presence or absence of emergency information based on whether or not the multimedia data of the emergency information has been received. The multimedia data of the emergency information transmitted to the base station 2 may be so-called wide area emergency information having the same contents among many base stations 2, or one or a small number of base stations 2. It may be so-called local emergency information that is closely related to the area where the contents are the same.

If it is determined in step ST1d that there is no emergency information, the process proceeds to step ST4d. On the other hand, when it is determined that there is emergency information, the downlink common channel transmission unit 36 of the base station 2 sets "Yes" to the emergency information flag in BCCH transmitted through S-CCPCH which transmits multimedia data of emergency information. Set the indicated digital value (step ST2d). For example, when the emergency information flag is set to 1-bit digital data, the digital value 1 is set to have emergency information, and the digital value 0 is set to no emergency information, the downlink common channel transmitter 36 changes the emergency information flag from the digital value 0 to 1. change.

Next, base station 2 adds BCCH Modify information to PCCH (step ST3d). The BCCH Modify information indicates the changed content when the BCCH content is changed as shown in the fourth embodiment. This information is added by the downlink common channel transmitter 36.

Base station 2 transmits PICH to the mobile terminal 1 under its umbrella in its own cell (step ST4d). Next, the base station 2 adds the information (emergency information channel information) necessary for the mobile terminal 1 to receive the emergency information channel during MCCH (step ST5d). As the emergency information channel information, for example, an emergency information channel number or the like can be considered as in the first embodiment. This information is added by the downlink common channel transmitter 36.

If the emergency information channel information is determined in advance by the mobile communication system and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, the base station 2 starts from. It is not necessary to notify the mobile terminal 1 of this information. In this case, step ST5d can be omitted. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

Further, when the emergency information channel information is determined by the base station 2, the base station 2 can omit step ST5d by notifying the mobile terminal 1 under its control in its own cell in advance. it can. For example, the broadcast information transmission unit 34 of the base station 2 notifies this information in advance using P-CCPCH as a part of the broadcast information. By doing so, the processing load on the base station 2 can be reduced, and the radio resources can be effectively utilized for other processing.

Next, the base station 2 transmits the MCCH to the mobile terminal 1 under its control (step ST6d). When it is determined that there is emergency information, the downlink common channel transmitter 36 of the base station 2 maps the emergency information received via the base station controller 3 to the emergency information channel in MTCH (step ST7d). ). After that, the base station 2 transmits MTCH to the mobile terminal 1 under the umbrella of receiving the MBMS in its own cell via the antenna 42 by the transmission process described above (step ST8d). The processing order from step ST2d to step ST7d may be arbitrary, or these processes may be performed at the same time.

In step ST9d, the mobile terminal 1 receives the PICH from the base station 2 and determines the presence or absence of information (PI; Paging Indicator) for its own station (own terminal). For example, the content of PICH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 determines whether or not there is information for its own station by the PICH. At this time, if it is determined that there is no information for its own station, the mobile terminal 1 returns to the process of step ST9d and periodically repeats the reception of PICH.

On the other hand, when it is determined that there is information for the own station, the mobile terminal 1 starts receiving S-CCPCH from the base station 2 based on the information for the own station (step ST10d), and the mobile terminal 1 starts receiving the S-CCPCH. Determines the presence or absence of BCCH Modify information in the PCCH transmitted through (step ST11d). For example, the contents of the PCCH received by the mobile terminal 1 are sent to the control unit 33, and the control unit 33 analyzes the PCCH and determines whether or not there is BCCH Modify information. At this time, if there is no BCCH Modify information, the mobile terminal 1 determines whether or not there is a call (step ST12d). Here, if there is no call, the process returns to step ST9d, and if there is a call, the incoming call process is executed and voice and data communication is started (step ST13d).

If it is determined in step ST11d that there is BCCH Modify information, mobile terminal 1 receives BCCH from base station 2 (step ST14d) and determines the presence or absence of emergency information from the value of the emergency information flag in this BCCH. (Step ST15d). For example, the content of BCCH received by the mobile terminal 1 is sent to the control unit 33, and the control unit 33 determines the presence or absence of emergency information based on the value of the emergency information flag in BCCH. Here, if it is determined from the value of the emergency information flag that there is no emergency information, the mobile terminal 1 shifts to the process of step ST17d, executes the normal BCCH update process, and then returns to the process of step ST9d. ..

When it is determined in step ST15d that there is emergency information, the mobile terminal 1 receives the MCCH transmitted from the base station 2 as described above (step ST16d), and the base station according to the emergency information channel information in the MCCH. Start receiving the emergency information channel in MTCH sent from 2 (step ST18d).

If the emergency information channel information is determined in advance in the mobile communication system in step ST18d, and both the mobile terminal 1 and the base station 2 in the mobile communication system recognize this information, According to this information, the mobile terminal 1 starts receiving the emergency information channel during MTCH. In addition, when the emergency information channel information is determined by the base station 2, the base station 2 uses P-CCPCH, for example, as a part of the notification information for the mobile terminal 1 under its control in its own cell. Notify in advance. In this case, the mobile terminal 1 can start receiving the emergency information channel during MTCH according to the emergency information channel information notified in advance.

When the mobile terminal 1 starts receiving the emergency information channel, it notifies the user that it has started receiving emergency information by displaying sound, vibration, and characters on the screen of the display device (step ST19d). For example, even during a call or packet communication, the control unit 33 controls a voice output unit (not shown), a vibration mechanism, and a display processing unit according to the start of reception of the emergency information channel, as described above. Notify emergency information. In the above-described fifth embodiment, the case where the mobile terminal is in the standby state (Idle state) is shown, but since this method uses PICH, it can also be applied to the CELL_PCH state and the URA_PCH state.

As described above, according to the fifth embodiment, since the emergency information flag (emergency information indicator) indicating the presence or absence of emergency information is provided in BCCH, the mobile terminal 1 that has not received MBMS data in the standby state is provided. Even if there is, BCCH can notify the occurrence of emergency information and receive the emergency information channel in MBMS. Further, as in the fourth embodiment, the BCCH can be received even by the mobile terminal 1 that does not support MBMS, so that the base station 2 can receive all the mobile terminals 1 in its own cell. It is possible to notify the presence or absence of emergency information. In the above embodiments 4 and 5, the base station 2 adds the information (emergency information channel information) necessary for the mobile terminal 1 to receive the emergency information channel during the MCCH, and the emergency information channel during the MTCH. Although the emergency information is mapped to, the base station controller 3 may perform these processes. In this case as well, it is possible for each base station 2 to transmit so-called wide-area emergency information having the same content from the plurality of base stations 2 without performing the above processing, and the mobile terminal at the cell end can be the plurality of base stations. The reception power from 2 can be combined, the reception quality can be improved, and emergency information can be transmitted quickly and accurately.

In the fourth embodiment, the information indicating that the BCCH content has been changed to the PAGING TYPE 2 in the DCCH (BCCH Modify information) is changed, and in the fifth embodiment, the BCCH content is changed to the PAGING TYPE 1 in the PCCH. Information indicating that (BCCH Modify information) has been added, but information indicating that there is urgent information or urgent information may be added as well as indicating that the information has been changed. The information indicating that there is such emergency information may be information indicating that there is emergency information in MCCH, or / and information indicating that there is emergency information in BCCH. By doing so, the mobile terminal can quickly determine the presence or absence of emergency information, and the control delay in the emergency information notification can be reduced, so that the time until receiving the emergency information can be shortened. ..

Further, in the fourth embodiment, the information indicating that the BCCH content has been changed to the PAGING TYPE 2 in the DCCH (BCCH Modify information) is changed, and in the fifth embodiment, the BCCH content is changed to the PAGING TYPE 1 in the PCCH. Although information indicating that the information has been modified (BCCH Modify information) has been added, it may be information indicating that the contents of the MCCH have been changed, not information indicating that the contents of the BCCH have been changed. By doing so, the MCCH can be received immediately without receiving the BCCH, and the emergency information channel can be received according to the information about the emergency information channel in the MCCH. Therefore, the mobile terminal can quickly determine the presence or absence of emergency information, and the control delay in the emergency information notification can be reduced, which has the effect of shortening the time until the emergency information is received.

As the emergency information flag shown in the first to fifth embodiments, the case of 1 bit is described in particular, but it may represent emergency information. Further, when the emergency information is available, the mobile terminal 1 may determine that the emergency information is available. By doing so, it is possible to notify not only the presence or absence of emergency information but also information such as the content type of emergency information and the place where an emergency occurs.

As shown in the first to fifth embodiments, in the present invention, the base station 2 can notify all mobile terminals 1 in its own cell that an emergency has occurred. By sending emergency information to the broadcast multimedia service, all mobile terminals 1 that support MBMS automatically connect to the emergency information channel regardless of the status, putting an excessive load on the mobile communication network. Instead, it is possible to notify an unspecified number of users of emergency information without lacking breaking news without adding special hardware to the mobile terminal 1.

In the above explanation, the case of using MBMS, which is a broadcast multimedia service in 3GPP, is shown, but it is not limited to MBMS, and a large amount of data is broadcast using a mobile communication network. The present invention can be applied to any broadcast-type multimedia service to be distributed.

Further, although the above example is an example in the W-CDMA system, the present invention can also be applied to notification of emergency information in other communication systems. For example, it can be applied to LTE (Long Term Evolution LTE) described in the background technology and CDMA2000 1x EV-DO.

As described above, the mobile communication system, the base station, and the mobile terminal station according to the present invention include a mobile terminal and a base station that relays communication between the network side and the mobile terminal, and is a broadcast type from the base station to the mobile terminal. In a mobile communication system capable of distributing information by a multimedia service, a base station sets a flag indicating the presence or absence of emergency information in a control channel for a broadcast multimedia service, and sets a flag indicating the presence or absence of emergency information to the mobile terminal according to the flag content of the control channel. Since it is configured to notify the presence or absence of emergency information, it is suitable for use in mobile communication systems, base stations, mobile terminal stations, etc. for notifying emergency information.