TWI393379B - Mobile communication system, base station, mobile station, and radio communication method - Google Patents

Description

Mobile communication system, base station, mobile station, and wireless communication method Field of invention

The invention relates to a mobile communication system, a base station, a mobile station, and a wireless communication method.

Background of the invention

Currently, mobile communication systems and mobile communication systems such as the Wireless MAN (Metropolitan Area Network) are widely used. In addition, in order to achieve higher speed and larger capacity of mobile communications, active communication is being continued for the next generation of mobile communication technologies.

For example, in 3GPP (3rd Generation Partnership Project), which is one of the standardization bodies, communication specifications called LTE (Long Term Evolution) that can communicate using a frequency band of up to 20 MHz (see, for example, Non-Patent Documents 1 and 2) ). Furthermore, a communication standard called LTE-A (LTE-Advanced) that can communicate using five bands (ie, a band of 100 MHz) of up to 20 MHz (for example, refer to Non-Patent Document 3) has been proposed as the next generation of LTE. Communication specifications.

Further, in such a communication standard, a so-called MBSFN (Multimedia Broadcast Multicast Service Single Frequency Network) data transmission method has been used for review (see, for example, Non-Patent Document 3). In the case of MBSFN, the plurality of base stations transmit the same content data at the same timing and using the same frequency and the same modulation method. The data transmitted by MBSF is called MBMS (Multimedia Broadcast Multicast Service) data. The mobile station combines the received signals from multiple base stations to improve reception quality.

Further, regarding the transmission of the MBMS data, it has been proposed that the user device transmits the feedback information to the base station device when the MBMS data does not meet the predetermined quality, and the base station device determines whether or not to adapt to the modulation according to the feedback information ( For example, refer to Non-Patent Document 3). Further, it has been proposed that the base station transmits the MBSFN reference signal associated with the MBSFN to the mobile station, and distinguishes the subframe used for the MBSFN transmission (MBSFN subframe) from the non-MBSFN subframe (for example, refer to the non-patent). [0095], [0096] of Document 2).

Advanced technical literature Patent literature

Patent Document 1: JP-A-2008-278339

Patent Document 2: JP-A-2009-253614

Non-patent literature

Non-Patent Document 1: 3GPP (3rd Generation Partnership Project), "Evolved Universal Treeestrial Radio Access (E-UTRA) and Evolved Universal Treeestrial Radio Access Network (E-UTRAN); Overall description", 3GPP TS 36.300 V9.1.0, 2009- 09.

Non-Patent Document 2: 3GPP (3rd Generation Partnership Project), "Evolved Universal Treeestrial Radio Access (E-UTRA) Radio Resource Control (RRC); Protocol specification", 3GPP TS 36.331 V9.0.0, 2009-09.

Non-Patent Document 3: 3GPP (3rd Generation Partnership Project), "Feasibility study for Further Advancements for E-UTRA (LTE-Advanced)", 3GPP TR 36.912 V9.0.0, 2009-09.

For example, in the LTE-A system, in a mobile communication system in which a plurality of frequency bands can be used, a plurality of base stations can transmit data of the same content to the mobile station at the same timing. However, in such a mobile communication system, how to efficiently utilize the radio resources of the complex frequency band constitutes a problem.

For example, the structure of the MBSFN sub-frame is different from that of the non-MBSFN sub-frame. Therefore, it is possible to consider the possibility of not being able to accommodate user data of a type other than MBMS data. Moreover, the MBSFN transmission can be started by the mobile station transmitting a request to the base station. Therefore, the mobile station requires MBSFN transmission in an arbitrary frequency band. When the base station wants to start MBSFN transmission in the arbitrary frequency band according to the request from the mobile station, the MBSFN frame that cannot accommodate other types of user data is dispersed. . As a result, the utilization efficiency of wireless resources will become lower.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a mobile communication system, a base station, a mobile station, and a wireless communication capable of improving utilization efficiency of radio resources when a plurality of base stations transmit data of the same content at the same timing. method.

In order to solve the above problems, a mobile communication system including a base station and a mobile station is provided. The base station includes a generating unit and a transmitting unit. The generating unit generates notification information indicating that the frequency band used for transmitting the same content at the same timing as the other base stations is used in the plurality of frequency bands usable by the wireless communication. The transmitting unit uses wireless to notify the notification information. The mobile station includes a receiving unit and a control unit. The receiving unit receives the notification information notified by the base station. The control unit controls the receiving of the same content that has been transmitted by the base station and other base stations at the same timing according to the notification information.

Moreover, in order to solve the above problems, a wireless communication method including a mobile communication system of the first base station and the second base station and the mobile station is provided. In the wireless communication method, the first base station generates notification information indicating that a frequency band of the same content is transmitted in the same frequency band as the second base station in the plurality of frequency bands usable by the wireless communication. The first base station uses wireless to notify the notification information. The mobile station receives the notification information notified by the first base station. The mobile station receives the data of the same content transmitted by the first and second base stations at the same timing based on the received notification information.

According to the above mobile communication system, base station, mobile station, and wireless communication method, the utilization rate of the wireless resources when the plurality of base stations transmit the same content data at the same timing can be improved.

The above and other objects, features and advantages of the present invention will become apparent from the <RTIgt;

Simple illustration

Fig. 1 is a view showing a mobile communication system according to the first embodiment.

Fig. 2 is a view showing the mobile communication system of the second embodiment.

Fig. 3 is a diagram showing a setting example of a carrier component.

Fig. 4 is a diagram showing a first example of carrier aggregation.

Fig. 5 is a diagram showing a second example of carrier aggregation.

Figure 6 is a diagram showing an example of spectrum aggregation.

Fig. 7 is a view showing a configuration example of a radio frame.

Fig. 8 is a diagram showing a first allocation example of the extended entity notification channel.

Fig. 9 is a diagram showing a second allocation example of the extended entity notification channel.

Fig. 10 is a diagram showing a third allocation example of the extended entity notification channel.

Fig. 11 is a diagram showing a structural example of a symbol.

Fig. 12 is a block diagram showing a base station of the second embodiment.

Fig. 13 is a block diagram showing a mobile station according to the second embodiment.

Fig. 14 is a flow chart showing the processing of the mobile station in the second embodiment.

Fig. 15 is a sequence diagram showing an example of MBSFN control in the second embodiment.

Fig. 16 is a view showing an example of allocation of a sub-frame for MBSFN.

Fig. 17 is a diagram showing a calculation mode of the number of synthesis of MBSFN.

Fig. 18 is a block diagram showing a base station of the third embodiment.

Fig. 19 is a block diagram showing a mobile station according to the third embodiment.

Fig. 20 is a flow chart showing the processing of the mobile station in the third embodiment.

Fig. 21 is a sequence diagram showing an example of MBSFN control in the third embodiment.

Fig. 22 is a sequence diagram showing another example of MBSFN control in the third embodiment.

Fig. 23 is a view showing the mobile communication system of the fourth embodiment.

Fig. 24 is a sequence diagram showing an example of the first MBSFN control in the fourth embodiment.

Fig. 25 is a sequence diagram showing an example of the second MBSFN control in the fourth embodiment.

Fig. 26 is a sequence diagram showing an example of the third MBSFN control in the fourth embodiment.

Fig. 27 is a view showing a modification of the mobile communication system according to the fourth embodiment.

Form for implementing the invention

The present embodiment will be described in detail below with reference to the drawings.

[First Embodiment]

Fig. 1 shows a mobile communication system according to the first embodiment. The mobile communication system according to the first embodiment includes base stations 1, 2 and a mobile station 3.

The base stations 1 and 2 are respectively wireless communication devices capable of wirelessly communicating with the mobile station 3. The base station 1 and the base station 2 are connected directly or through a host network. The base station 1 uses a plurality of frequency bands for wireless communication. The base station 2 can also use the complex frequency band. The mobile station 3 is a wireless communication device that is connected to the base stations 1 and 2 and performs wireless communication, and is, for example, a terminal device such as a mobile phone or a mobile information terminal device. The mobile station 3 performs wireless communication using a frequency band of one or more of the above complex frequency bands.

The base station 1 includes a generating unit 1a and a transmitting unit 1b. The generating unit 1a generates notification information that can be displayed in a plurality of frequency bands and used for transmitting a frequency band of the same content data at the same timing as other base stations (for example, the base station 2). This frequency band can also be set to be the same for the base station 1 and the base station 2. Further, the modulation method applied to the data transmission may be set to be the same between the base station 1 and the base station 2. The transmitting unit 1b wirelessly transmits (broadcasts) the notification information generated by the generating unit 1a. The base station 2 can also be constructed in the same manner as the base station 1 to notify the display of the notification information of the frequency band to be used.

The mobile station 3 includes a receiving unit 3a and a control unit 3b. The receiving unit 3a receives the notification information transmitted by the base station 1. The control unit 3b controls the process of receiving the same content material transmitted by the base station 1 and other base stations (e.g., the base station 2) at the same timing based on the received notification information. The mobile station 3 combines signals from the base station 1 and signals from the base station 2, for example, and demodulates and decodes them to improve reception quality. The mobile station 3 can also synthesize signals from more than three base stations.

Here, the base station 1 may transmit the notification information generated by the generating unit 1a using the notification channel. The notification channel may also be the same channel as the notification channel for transmitting the information used by the mobile station 3 to the base station 1, or may be a different channel. In the latter case, the channel (the first notification channel) for transmitting the information for connecting the base station 1 is a channel that is commonly referred to by the first and second types of mobile stations, and the notification information generated by the transmission generating unit 1a may be used. The channel (second notification information) is a channel that is referred to by the mobile station of the first type, but is not referred to by the mobile station of the second type. Further, the base station 1 can also transmit (notify) the notification information generated by the generating unit 1a by using the control channel.

Further, the base station 1 can also use the lowest frequency band of the plurality of frequency bands for the plurality of base stations to transmit the same content data at the same timing. Further, the base station 1 can also assign identification information to the plurality of frequency bands. This identification information can be used in the notification information to display the frequency band to be used. For example, a cell ID or a unique number in the same partition or the like can be used as the identification information. When the partition ID is used as the identification information, one partition is assigned a plural partition ID.

Further, the mobile station 3 may switch the frequency band to be used when the frequency band indicated by the received notification information is different from the frequency band used for the connection between the mobile station 3 and the base station 1. In this case, the mobile station 3 may use the radio resource corresponding to the frequency band after the handover after the handover, and request the base station 1 to transmit the data of the same content at the same timing. Or, the radio resource corresponding to the frequency band before the handover is used before the handover, and the base station 1 is required. Further, not only the handover of the base station to which the destination is connected but also the switching of the frequency band is also referred to as handover.

This mobile communication system can be implemented as, for example, LTE-A. In this case, the complex frequency bands may be referred to as a component carrier (CC: Component Carrier) or a carrier component (CC: Carrier Component), respectively. Further, the first type of mobile station may be a mobile station corresponding to LTE, and the second type of mobile station may be implemented as a mobile station corresponding to LTE-A. Further, the first notification channel may be set as a notification channel defined by LTE and LTE-A, and the second notification channel may be implemented as an extension notification channel not defined in LTE.

In the mobile communication system according to the first embodiment, the base station 1 generates notification information that can be displayed in a plurality of frequency bands that can be used for wireless communication, and is used to transmit the same content at the same timing as the base station 2. The frequency band of the data. The generated notification information is notified by wireless. Further, the mobile station 3 receives the notification information of the base station 1. The data of the same content transmitted by the base stations 1 and 2 at the same time sequence is received according to the received notification information.

That is, the radio resources used by the plurality of base stations to transmit the same content at the same timing induce the mobile station to a specific frequency band so that the entire plurality of frequency bands are not dispersed. Thereby, the utilization efficiency of the radio resources when the plurality of base stations transmit the same content data at the same timing can be used. In particular, information indicating that the frequency band to be used is notified, so the mobile station 3 can select an appropriate frequency band before starting the reception processing. Further, when the low frequency band is used in the complex frequency band, the reach of the radio wave becomes wider, and the mobile station 3 can receive and synthesize signals from the farther base station. Therefore, the reception quality of the mobile station 3 can be further improved.

In the following second to fourth embodiments, the case where the wireless communication method according to the first embodiment is applied to the LTE-A system will be considered. However, the above wireless communication method can of course be applied to other types of wireless communication systems.

[Second Embodiment]

Fig. 2 shows a wireless communication system according to the second embodiment. The wireless communication system according to the second embodiment includes base stations 100 and 200, a mobile station 300, and a core network 40. The core network 40 is provided with an MME (Mobility Management Entity) 410, an MBMS gateway 420, and a SAE (System Architecture Evolution) gateway 430. This wireless communication system is a system that can correspond to the LTE-A communication specifications.

The base stations 100 and 200 are wireless communication devices that can wirelessly communicate with the mobile station 300. The base station 100 is connected to the wired network, that is, to the core network 40, and transfers data between the mobile station 300 and the core network 40. The base stations 100 and 200 use five carrier components (hereinafter referred to as CC) for wireless communication. Further, the base stations 100 and 200 can perform MBSFN transmission, that is, transmit MBMS data of the same content using the same frequency at the same timing.

Further, the base stations 100 and 200 perform an operation of MCE (Multi-cell/multicast Coordination Entity) for controlling MBSFN transmission. That is, in the base stations 100 and 200, the base station to which the mobile station 300 is connected specifies a plurality of base stations to which MBSFN transmission is to be performed, and the radio resources used for MBSFN transmission are scheduled. In the following description, the base station 100 is considered to control the MBSFN transmission to the mobile station 300.

The mobile station 300 is a wireless terminal device that performs wireless communication with the base stations 100 and 200, and is, for example, a mobile phone or a mobile information terminal. In the downlink (the wireless link from the base station 100, 200 to the mobile station 300), the mobile station 300 can simultaneously use up to five CCs to receive data. Further, in the uplink (the radio link from the mobile station 300 to the base stations 100 and 200), it is possible to simultaneously use two CCs to receive data. The number of CCs that can be used by the mobile station 300 is controlled by the base stations 100, 200.

Further, the mobile station 300 receives the MBMS data transmitted by the base stations 100 and 200 for MBSFN transmission. That is, the mobile station 300 performs an MBSFN request on the connected base station. A signal including MBMS data of the same content transmitted using the same frequency at the same timing is received from the base stations 100 and 200, and the received signals are combined and demodulated or decoded. Further, the MBSFN transmission may be performed using only one CC, or may be performed using a plurality of CCs at the same time. In the following description, the case where MBSFN transmission is performed using only one CC is considered.

The MME 410 is a device that performs mobility management of the mobile station 300. The MME 410 communicates with the base stations 100, 200 and manages the partition in which the mobile station 300 is located. The MBMS gateway 420 is a device that processes MBMS data received by the mobile station. The MBMS gateway 420 transfers the MBMS data destined for the mobile station 300 to the base stations 100, 200. The SAE gateway 430 is a device that processes the user data (excluding MBMS data) that the mobile station 300 transmits. The SAE gateway 430 transfers the user data destined for the mobile station 300 to the base station 200.

Further, in the second embodiment, a mobile station that does not use a plurality of CCs is referred to as an LTE mobile station. A mobile station that can collect a plurality of CCs is referred to as an LTE-A mobile station. The mobile station 300 is an LTE-A mobile station. Both the LTE-A mobile station and the LTE mobile station can be connected to the base stations 100 and 200. In 3GPP, the communication specifications of LTE are defined by the specification of Release 9, and the communication specifications of LTE-A are defined by the specification of Release 10.

Fig. 3 is a diagram showing a setting example of a carrier component. The base stations 100 and 200 use five CCs as shown in FIG. When dual frequency division (FDD: Frequency Division Duplex) is used for communication between the two parties, the frequency bands of CC #1 to #5 can be secured for the downlink (DL: DownLink) and the uplink (UL: UpLink), respectively. In the following description, when only CC#1 to #5 are referred to, it means a group of a frequency band of DL and a frequency band of UL. The bandwidth of each of the DL and UL CCs is 20 MHz, and the overall bandwidth is 100 MHz. The base stations 100 and 200 perform radio resource allocation (scheduling) to CC #1 to #5, respectively.

Further, in the example of Fig. 3, bidirectional communication is realized by FDD, but it can also be realized by two-dimensional time division (TDD: Time Division Duplex). In this case, 5 CCs are set without distinguishing DL from UL on the frequency axis. Further, in the example of Fig. 3, all CC frequency widths are set to 20 MHz, but other bandwidths (for example, 5 MHz, 10 MHz, 15 MHz, etc.) may be set. Further, all CC band widths may not be set to be the same.

Moreover, in the example of FIG. 3, the UL radio resource is set to the low frequency side, and the DL radio resource is set to the high frequency side. Since the signal transmission loss of the low frequency is small, the transmission power of the mobile station 300 can be kept low in a state where the UL radio resource is set to the low frequency side. However, the configuration of the UL radio resource and the DL radio resource may be reversed.

As described above, the mobile station 300 aggregates the complex CCs in CC#1 to #5, and can perform wider bandwidths than the one CC bandwidth (for example, 20 MHz) (for example, 40 MHz, 60 MHz, 80 MHz, 100 MHz). Etc.) Send and receive data.

Here, CC#1 to #5 may be all set in one of the 800 MHz band, the 2.5 GHz band, the 3.5 GHz band, or the like, or may be dispersed in different complex bands. The case of aggregating a plurality of consecutive or discontinuous CCs belonging to the same frequency band is referred to as Carrier Aggregation. In contrast, a case of aggregating CCs belonging to different frequency bands is referred to as Spectrum Aggregation.

Fig. 4 is a diagram showing a first example of carrier aggregation. In the example of Fig. 4, four discontinuous 5 MHz wide frequency bands and three discontinuous 20 MHz wide frequency bands are prepared for the 3.5 GHz band as a frequency band that can be used for wireless communication. CC#2 of 20 MHz width is formed by aggregating four 5 MHz bands. Also, one band of 20 MHz width is defined as CC#3.

The mobile station 300 can use, for example, CC#2 and #3 as a frequency band of 40 MHz (logically one frequency band) by carrier aggregation. In this case, the mobile station 300 actually uses four 5 MHz wide frequency bands belonging to the 3.5 GHz band and one 20 MHz wide frequency band. Further, Fig. 4 shows an example of a frequency band belonging to the 3.5 GHz band. However, it is also possible to use a frequency band smaller than 20 MHz for other frequency bands such as an 800 MHz band.

Fig. 5 is a diagram showing a second example of carrier aggregation. In the example of Fig. 5, a frequency band of 80 MHz width is prepared for the 3.5 GHz band as a frequency band that can be used for wireless communication. The 80 MHz wide frequency band is divided into four, and is defined as CC #2 to #5 of 20 MHz width.

The mobile station 300 aggregates carriers such as CC#2 and #3, and can be used as a frequency band of 40 MHz (theoretical is one frequency band). In this case, the mobile station 300 actually uses a part of the frequency band of the continuous 80 MHz width belonging to the 3.5 GHz band.

Figure 6 is a diagram showing an example of spectrum aggregation. In the example of Fig. 6, a frequency band of 20 MHz width is prepared for the 800 MHz band as a frequency band that can be used for wireless communication. Further, a frequency band of 80 MHz width is prepared for the 3.5 GHz band as a frequency band that can be used for wireless communication. The band of 20 MHz width of the 800 MHz band is defined as CC #1, and the band of 80 MHz width of the 3.5 GHz band is divided into four, which are defined as CC #2 to #5 of 20 MHz width, respectively.

The mobile station 300 can use, for example, CC #1 to #5 as a frequency band of 100 MHz (the theoretical one frequency band) by spectrum aggregation. In this case, the mobile station 300 actually uses a frequency band of 20 MHz width belonging to the 800 MHz band and a frequency band of 80 MHz width belonging to 3.5 GHz. Further, as shown in FIG. 4, a plurality of frequency bands having a bandwidth smaller than 20 MHz belonging to the 800 MHz band may be aggregated to form CC #1.

The arrival distance of the 800MHz band is longer than the 3.5GHz band, which can constitute a more stable wireless communication. Therefore, CC#1 belonging to the 800MHz band can be preferentially used for transmitting and receiving data or receiving and receiving important data between the base station and the mobile station separated by a distance. In this case, CC#1 can also be referred to as anchor CC.

Figure 7 is a diagram showing the construction side of wireless communication. In each of CC#1 to #5, the radio frame shown in FIG. 7 is transmitted and received between the base stations 100 and 200 and the mobile station 300. However, the structure of FIG. 7 is an example, and the structure of the radio frame is not limited to this.

In this example, the radio frame in the 10ms period contains 10 sub-frames with a width of 1ms. Each sub-frame contains 2 slots with a width of 0.5 ms. That is, the radio frame in the 10 ms period includes 20 slots (slots #0 to #19).

In the DL radio frame, slots #0 and #10 can be allocated a primary synchronization channel (P-SCH: Primary Synchronization CHannel) and a secondary synchronization channel (S-SCH: Secondary Synchronization CHannel) for transmitting a synchronization signal. Further, the slot #1 may allocate an entity notification channel (PBCH: Physical Broadcast CHannel) and an extended physical broadcast channel (E-PBCH: Extended Physical Broadcast CHannel) for transmitting (notifying) the notification information.

The radio resources in the radio frame are subdivided and managed in the time direction and the frequency direction. OFDMA (Orthogonal Frequency Division Multiple Access) is used for the DL frame, and SC-FDMA (Signal-Carrier Frequency Division Multiple Access) is used for the UL frame. Radio resources in the field of time x frequency are allocated to various channels.

For the time direction, the slot contains 7 or 6 symbols. An interval signal called CP (Cyclic Prefix) is inserted into the symbol. There are two types of CPs in the CP that have different lengths of the normal CP (regular CP) and the extended CP. When using a normal CP, one slot contains seven symbols, and when using an extended CP, one slot contains six symbols. For the frequency direction, the CC contains a plurality of subcarriers.

Fig. 8 is a diagram showing a first allocation example of the extended entity notification channel. In Fig. 8, the longitudinal direction is the time axis and the lateral direction is the frequency axis. Further, the example of Fig. 8 shows a case where a normal CP is used as the CP, that is, a case where one slot contains seven slots is displayed.

In the DL frame, the first symbol of the slot #0 can be assigned a PCFICH (Pystic Control Format Indicator CHannel) and a PHICH (Pystic Hybrid Automatic Repeat Request Indicator CHannel). The PCFICH is used to notify a channel that can allocate the number of symbols of the PDCCH (Physical Downlink Control CHannel). The PHICH is a channel for replying to an ACK (ACKnowled gement) response or a NACK (Negative ACKnowled gement) response to data reception. The PHICH also has a case where it is assigned to the third symbol.

Further, the first symbol of the slot #0 can allocate the PDCCH described above. The PDCCH is a channel for transmitting control information of L1/L2 (Layer 1/Layer 2). The PDCCH is also allocated to the second symbol and the third symbol. The number of symbols of the PDCCH is variable from one to three.

Further, the sixth symbol of the slot #0 can allocate the aforementioned S-SCH. The seventh symbol can allocate the aforementioned P-SCH. The P-SCH system can transmit a channel of one of a predetermined number (for example, three) of the main synchronization signal series. The S-SCH system can transmit a predetermined number (for example, 168) of channels of one of the series of io2 signals to be synchronized. The combination of the P-SCH series and the S-SCH series (for example, three × 168 = 504 combinations) corresponds to the partition ID.

Further, the first to fourth symbols of the slot #0 may be assigned to the PBCH, and the fifth to seventh symbols may be assigned to the E-PBCH. In the field of radio resources, E-PBCH and PBCH are adjacent in the time direction. The PBCH is a notification channel defined by LTE and LTE-A in common. E-PBCH is a notification channel added by LTE-A. That is, the LET-A mobile station, that is, the mobile station 300 can detect both the PBCH and the E-PBCH. On the other hand, the LTE mobile station can detect the PBCH, but the E-PBCH cannot be detected.

The notification information transmitted by the PBCH includes the information that the mobile station 300 uses to connect the CC having the PBCH. For example, the notification information of the PBCH includes information showing the display bandwidth (for example, 5 MHz, 10 MHz, 15 MHz, 20 MHz). This is because LTE and LTE-A have variable bandwidth.

The notification information (extension notification information) sent by the E-PBCH may contain information about the plural CC. For example, it is contemplated that the base stations 100, 200 limit the CCs used for the MBSFN to enable efficient scheduling. In this case, it is considered that the information indicating the CC for MBSFN transmission among the CC#1 to #5 is included in the extension notification information and transmitted. Thereby, the mobile station 300 can know the usable CC before performing the MBSFN request to the base station 100. Further, the extension notification information can also be used to display the CCs that can be used for MBSFN transmission by using the IDs assigned in advance to CC#1 to #5.

As shown in FIG. 8, the S-SCH, the P-SCH, the PBCH, and the E-PBCH are all allocated to one frequency (subcarrier) of one CC, and may be allocated only to a part of frequencies (subcarriers). For example, it is set to a frequency assigned to the vicinity of the center of the CC. The reason why the frequency is allocated near the center of the vicinity of the non-CC boundary is to facilitate the channel detection by the mobile station 300. The frequency allocated to the E-PBCH may be the same as or different from the frequency assigned to the PBCH.

Further, the DL frame transmits a known pilot signal, that is, a reference signal (RS: Reference Signal), using a part of resources other than the radio resources used by the channel. The mobile station 300 can measure the reception quality using the reference signal.

Fig. 9 is a diagram showing a second allocation example of the extended entity notification channel. The assignment example of Fig. 9 is the same as the example shown in Fig. 8 except for the setting position of the E-PBCH. In the example of Fig. 9, the fourth to fifth symbols of the slot #0 can be assigned E-PBCH. In the field of radio resources, the E-PBCH and the S-SCH are adjacent in the time direction. The frequency allocated to the E-PBCH may be the same as or different from the frequency assigned to the S-SCH.

Fig. 10 is a diagram showing a third allocation example of the extended entity notification channel. The assignment example of Fig. 10 is the same as the example shown in Figs. 8 and 9 except for the setting position of the E-PBCH. In the example of Fig. 10, E-PBCH can be allocated to the fourth to fifth symbols of slot #0 and the fifth to seventh symbols of slot #1. In the field of radio resources, the E-PBCH is adjacent to the S-SCH and the PBCH in the time direction. The frequency allocated to the E-PBCH may be the same as or different from the frequency allocated to the S-SCH and the PBCH.

As described above, more extended notification information can be transmitted by increasing the amount of radio resources allocated to the E-PBCH. The radio resource allocated to the E-PBCH may also be made variable in accordance with the extension notification information to be transmitted. Further, as shown in FIGS. 8 to 10, the E-PBCH can be easily detected by the mobile station 300 by causing at least one of the synchronization channel and the PBCH to be adjacent in the time direction. However, it may be set to be adjacent to each other in the frequency direction other than the time direction. Alternatively, the E-PBCH may not be set adjacent to any of the synchronization channel and the PBCH. Further, the E-PBCH may be provided in all CCs or may be provided only in a part of CCs.

In addition, although the case where the normal CP is used as the CP (the case where one slot contains 7 symbols) is exemplified as an example, the case where the extended CP is used as the CP (the case where one slot contains 6 symbols) can also be used. The same consideration is given to setting the E-PBCH. In this case, for example, the method of Fig. 8 is to assign E-PBCH to the fifth to sixth symbols of slot #1, and the method of Fig. 9 is for the fourth symbol assignment E-PBCH of slot #0, Fig. 10 The method assigns an E-PBCH to the fourth symbol of slot #0 and the fifth to sixth symbols of slot #1.

Fig. 11 is a diagram showing a structural example of a symbol. As described above, there are normal CPs and extended CPs for the types of CPs. As shown in Figure 11, the CP is inserted in the data section, that is, before a valid symbol. The CP system has copied the signal at the end of the valid symbol. Usually, the length of the CP is 4.69 μsec, and the length of the extended CP is 16.67 μsec. The effective symbol length of one symbol is the same as the case of the extended CP in the case of the normal CP.

The extended CP is used, for example, in an MBSFN sub-frame (a sub-frame used for MBSFN transmission). In this case, the MBSFN subframe has six symbols containing valid symbols and CPs. Usually, the CP is used, for example, in a non-MBSFN sub-frame (not used for the sub-frame of MBSFN transmission). In this case, the non-MBSFN subframe has 7 symbols.

Fig. 12 is a block diagram showing a base station of the second embodiment. The base station 100 includes a transmission/reception antenna 111, a radio reception unit 112, a demodulation and decoding unit 113, a quality information generation unit 114, an MBSFN request extraction unit 115, a scheduler 116, a notification information generation unit 117, and an MBSFN notification information generation unit 118. The MBSFN control information generation unit 119, the RS generation unit 120, the mapping unit 121, the code modulation unit 122, and the wireless transmission unit 123. Further, the base station 200 can also be realized by the same module configuration as the base station 100.

The transmitting and receiving antenna 111 receives the wireless signal transmitted from the mobile station 300 and outputs it to the wireless receiving unit 112. Further, the transmitting/receiving antenna 111 wirelessly outputs the transmission signal acquired by the wireless transmitting unit 123. Further, the antenna for transmission and reception may be used instead of the antenna for reception and the antenna for reception. Alternatively, diversity transmission and reception antennas may be used for diversity transmission.

The radio reception unit 112 performs radio signal processing on the signal obtained by the transmission/reception antenna 111, and performs conversion of a high-frequency radio signal to a low-frequency baseband signal (down-conversion frequency conversion). The radio receiving unit 112 includes, for example, a low noise amplifier (LNA), a frequency converter, a band pass filter (BPF), and an A/D (Analog to Digital) conversion for wireless signal processing. And so on. The frequency band of the receiving object is indicated by the scheduler 116.

The demodulation and decoding unit 113 demodulates and corrects the fundamental frequency signal obtained by the radio reception unit 112, and outputs the obtained data (including user data and control information). The demodulation and decoding are performed by a method corresponding to a predetermined modulation coding scheme (MCS: Modulation and Coding Scheme) or a modulation coding scheme indicated by the scheduler 116. The candidate for the modulation method includes a digital modulation method such as QPSK (Quadrature Phase Shift Keying) or 16QAM (Quadrature Amplitude Modulation). The coding mode candidates include a Turbo code and a Low Density Parity Check (LDPC) code. The extracted user data is forwarded to the SAE gateway 430.

The quality information generating unit 114 extracts one of the control information transmitted by the mobile station 300, that is, a wireless quality measurement report (Measurement Report). The quality information generating unit 114 outputs the extracted measurement report to the scheduler 116.

The MBSFN request extraction unit 115 extracts the MBSFN request (the control information indicating the request for MBSFN transmission) sent from the mobile station 300. The MBSFN requirement is transmitted using an uplink physical shared channel (PUSCH: Physical Uplink Shared CHannel) already set in the UL radio frame. The MBSFN requires the extracting unit 115 to output the extracted MBSFN request to a module (not shown) for realizing the control function of the MCE already provided in the base station 100.

The scheduler 116 performs allocation of the radio resources to the mobile station 300 based on the measurement report acquired by the quality information generating unit 114. In this manner, the wireless receiving unit 112, the demodulation and decoding unit 113, the mapping unit 121, the code modulation unit 122, and the wireless transmission unit 123 are notified of the allocation of the radio resources. Further, the scheduler 116 adaptively selects the modulation coding method in accordance with the measurement report. In this way, the demodulation decoding unit 113 and the code modulation unit 122 are notified of the selected modulation and coding scheme.

The notification information generating unit 117 generates notification information transmitted (notified) by the PBCH for each CC. This notification information contains information showing the bandwidth of the CC. The MBSFN notification information generating unit 118 generates information capable of displaying CCs used for MBSFN transmission among CC #1 to #5. This notification information is transmitted, for example, in E-PBCH. The MBSFN control information generating unit 119 generates control information about the MBSFN. This control information includes the modulation coding method of the MBMS data and the information showing the transmission timing. This control information is transmitted using a physical multicast channel (PMCH: Physical Multicast CHannel) provided in the DL radio frame. The RS generating section 120 generates a known signal, that is, a reference signal.

Further, the notification information generated by the MBSFN notification information generating unit 118 may be notified by a channel other than the E-PBCH. For example, a method of notification by PBCH can be considered. Further, a method of notifying by using a channel (PMCH) that can transmit control information of the MBSFN can also be considered.

The mapping unit 121 maps the MBMS data received by the MBMS gateway 420 to the user data received by the SAE gateway 430 to the DL radio frame. Further, the control information/control signal generated by the notification information generation unit 117, the MBSFN notification information generation unit 118, the MBSFN control information generation unit 119, and the RS generation unit 120 is mapped to the DL radio frame. In this way, the mapped data is sequentially output to the code modulation unit 122.

The code modulation unit 122 erroneously corrects and modulates the data acquired by the mapping unit 121, generates a baseband signal as a transmission signal, and outputs it to the wireless transmission unit 123. The coding and modulation are performed using a predetermined modulation coding scheme or a modulation coding scheme indicated by the scheduler 116. The candidate for the modulation method includes a digital modulation method such as QPSK or 16QAM. The candidate for the coding mode includes a turbo code or an LDPC code.

The wireless transmitting unit 123 performs radio signal processing on the transmission signal obtained by the code modulation unit 122, and performs conversion (up-conversion) of the low-frequency baseband signal to the high-frequency wireless signal. The wireless transmitting unit 123 includes, for example, a D/A (Digital to Analog) converter, a frequency converter, a band pass filter, a power amplifier, and the like for wireless signal processing. The frequency band of the transmitting object is indicated by the scheduler 116.

Fig. 13 is a block diagram showing a mobile station according to the second embodiment. The mobile station 300 includes a transmission/reception antenna 311, a radio reception unit 312, a demodulation decoding unit 313, a notification information extraction unit 314, a terminal control unit 315, an MBSFN control information extraction unit 316, an MBSFN control unit 317, and an MBSFN notification information extraction unit 318. The MBSFN request generation unit 319, the RS extraction unit 320, the quality measurement unit 321, the quality information generation unit 322, the code modulation unit 323, and the wireless transmission unit 324.

The transmitting/receiving antenna 311 receives the wireless signals transmitted from the base stations 100 and 200 and outputs them to the wireless receiving unit 312. Further, the transmission/reception antenna 311 wirelessly outputs the transmission signal acquired by the radio transmission unit 324. Further, the transmitting antenna and the receiving antenna may be provided separately to the mobile station 300 instead of the antenna for both transmission and reception. Alternatively, diversity transmission and reception antennas may be used for diversity transmission.

The radio reception unit 312 performs radio signal processing on the signal obtained by the transmission/reception antenna 311, and performs conversion of a high-frequency radio signal to a low-frequency baseband signal (down-conversion). The wireless receiving unit 312 includes, for example, a low noise amplifier, a frequency converter, a band pass filter, an A/D converter, and the like for wireless signal processing. The frequency band of the reception target is instructed by the terminal control unit 315.

The demodulation decoding unit 313 demodulates and corrects the fundamental frequency signal obtained by the radio reception unit 312, and outputs the obtained data (including user data and control information). The demodulation and decoding are performed by a method corresponding to a predetermined modulation coding method or a modulation coding method instructed by the terminal control unit 315.

Here, when the base station 100, 200 performs MBSFN transmission, the signal transmitted by the base station 100 overlaps with the signal transmitted by the base station 200 in the received signal. The signals of the two are the same content, however, depending on the transmission distance to the mobile station 300, one party may be delayed from the other. That is, the direct wave and the delayed wave are superimposed on the mobile station 300. In this case, the radio receiving unit 312 can extract a signal corresponding to the delayed wave if the delay time is equal to or less than the CP length. The demodulation and decoding unit 313 can demodulate and decode the signals synthesized from the base stations thus extracted. Thereby, the receiving station 300 can improve the reception quality.

The notification information extracting unit 314 extracts the notification information notified by the base station 100, 200 by the PBCH at each CC. This notification information includes information showing the bandwidth of the CC on which the notification information has been sent. The notification information extracting unit 314 outputs the extracted notification information to the terminal control unit 315.

The terminal control unit 315 controls the connection to the base station 100 by referring to the notification information extracted by the notification information extracting unit 314. Further, before the base station 100 requests the MBSFN transmission, the terminal control unit 315 determines the CC that can be used for MBSFN transmission based on the notification information acquired by the MBSFN notification information extracting unit 318. Further, the modulation coding method and the reception timing applied to the MBMS data are specified based on the information notified from the MBSFN control unit 317. In this manner, the terminal control unit 315 controls the operations of the radio reception unit 312, the demodulation decoding unit 313, the code modulation unit 323, and the radio transmission unit 324.

The MBSFN control information extracting unit 316 extracts control information about the MBSFN transmitted by the base station by the PMCH. This control information includes the modulation coding method for MBMS data and the information showing the transmission timing. The MBSFN control information extracting unit 316 outputs the extracted control information to the MBSFN control unit 317.

The MBSFN control unit 317 controls the reception processing of the MBSFN. Specifically, when the MBSFN control unit 317 starts the MBSFN reception process, the MBSFN request generation unit 319 is instructed to transmit the MBSFN request. Further, the content of the control information extracted by the MBSFN control information extracting unit 316 is notified to the terminal control unit 315.

The MBSFN notification information extracting unit 318 extracts the extended notification information notified by the base station 100 by the E-PBCH. This extended notification information includes information indicating CCs that can be used for MBSFN transmission among CC #1 to #5. The MBSFN notification information extracting unit 318 outputs the extracted extension notification information to the terminal control unit 315. Further, when a channel other than the E-PBCH (for example, PBCH or PMCH) is notified to display the information of the usable CC, the MBSFN notification information extracting unit 318 extracts the notification information from the channel.

The MBSFN request generation unit 319 generates an MBSFN request based on an instruction from the MBSFN control unit 317, that is, generates control information indicating that the start of the MBSFN transmission is required to be displayed. The generated MBSFN request is transmitted through the code modulation unit 323 and the radio transmission unit 324, for example, on the PUSCH of the CC used in the MBSFN.

The RS extracting unit 320 extracts the reference signals transmitted from the base stations 100 and 200. In this way, the extracted reference signal is output to the quality measuring unit 321.

The quality measuring unit 321 measures the reception quality of each of CC #1 to #5 using the reference signal extracted by the RS extracting unit 320. In this way, the quality measuring unit 321 notifies the quality information generating unit 322 of the measurement result. For example, SIRN (Signal to Interference and Noise Ratio) can be used as an indicator for displaying reception quality.

The quality information generating unit 322 generates control information (measurement report) that can display the reception quality measured by the quality measuring unit 321. For example, a CQI (Channel Quality Indication) indicating the reception quality with a discrete value can be used as the measurement report.

The code modulation unit 323 corrects the encoding and the modulation of the user data transmitted to the base stations 100 and 200, the MBSFN request generated by the MBSFN request generating unit 319, and the measurement report generated by the quality information generating unit 322, and Corresponding to the UL radio resources allocated to the mobile station 300. The coding and modulation system uses a predetermined modulation coding method or a modulation coding method instructed by the terminal control unit 315. In this way, the baseband signal as the transmission signal is output to the wireless transmission unit 324.

The radio transmission unit 324 performs radio signal processing on the transmission signal obtained by the coding/modulation unit 323, and performs radio signal conversion (up-conversion frequency conversion) from a low-frequency baseband signal to a high frequency. The wireless transmitting unit 324 includes, for example, a D/A converter, a frequency converter, a band pass filter, a power amplifier, and the like for wireless signal processing. The frequency band of the transmission target is instructed by the terminal control unit 315.

Fig. 14 is a flow chart showing the processing of the mobile station in the second embodiment. Here, the case where the mobile station 300 performs the MBSFN request to the base station 100 is considered. The MBSFN request is performed, for example, when the mobile station 300 utilizes the service transmitted with the MBSFN (when the service flow is established). For example, an animation delivery service or the like can be considered as a service accompanying MBSFN transmission.

(Step S11) The mobile station 300 receives the notification information notified by the base station 100 to the PBCHs of CC #1 to #5. This notification information includes information used by the mobile station 300 to connect to each CC.

(Step S12) The mobile station 300 receives the notification information about the MBSFN notified by the base station 100 with at least one CC E-PBCH (or another channel such as PBCH or PMCH). This notification information includes information showing CCs that can be used for MBSFN transmission in CC#1 to #5.

(Step S13) The mobile station 300 refers to the notification information about the MBSFN that has been received in step S12, and selects the CC used for MBSFN transmission. That is, when it is possible to use for MBSFN transmission, one of the CCs designated by the base station 100 is selected. It is also possible to select one CC by referring to the reception quality of the mobile station 300 when a plurality of usable CCs have been designated.

(Step S14) The mobile station 300 transmits an MBSFN request to the base station 100 using the PUSCH of the CC selected in step S13. However, instead of the CC selected in step S13, the MBSFN request is transmitted using the CC currently used by the mobile station 300.

(Step S15) The mobile station 300 receives the control information of the MBSFN transmitted by the base station 100 at the PMCH of the CC selected in step S13. This control information includes information indicating the modulation coding method and transmission timing applicable to MBSFN transmission. Moreover, the control information is included in the logical channel, that is, information included in the MCCH (MBMS point-to-multipoint control CHannel) and the MSCH (MBMS point-to-multipoint Scheduling CHannel).

(Step S16) The mobile station 300 receives the MBMS data by referring to the control information received in step S13 on the PMCH of the CC selected in step S13. That is, the receiving base station 100, 200 synthesizes the signals of the same content transmitted at the same timing and at the same frequency, and extracts the MBMS data. Also, the MBMS data is included in the logical channel, that is, the data included in the MTCH (MBMS point-to-multipoint Traffic CHannel).

In this way, the mobile station 300 can know the CC that can be used for MBSFN transmission by referring to the information notified by the base station 100. Therefore, the mobile station 300 can efficiently perform the program at the start of the MBSFN transmission.

Fig. 15 is a sequence diagram showing an example of MBSFN control in the second embodiment. The sequence example shown in Fig. 15 shows a case where the base station 100 dominates and performs MBSFN transmission together with the base station 200.

(Step S21) The base station 100 transmits the notification information on the PBCH. Also, the notification information about the MBSFN is transmitted in E-PBCH (or other predetermined channel). The mobile station 300 detects the PBCH and the E-PBCH (or other predetermined channel) and extracts the notification information that the base station 100 has transmitted.

(Step S22) The mobile station 300 specifies the CCs that can be used for MBSFN transmission among the CC#1 to #5 based on the notification information about the MBSFN. As such, the mobile station 300 selects the CC to receive the MBMS data.

(Step S23) The mobile station 300 transmits an MBSFN request to the base station on the PUSCH of the selected CC (or the CC currently used by the mobile station 300). The base station 100 extracts the MBSFN request transmitted by the mobile station 300.

(Step S24) The base station 100 receives the MBSFN request from the mobile station 300 and performs control as an MCE. In other words, the base station 100 performs scheduling to determine the range of the base station to which the MBSFN transmission is to be performed, the modulation and coding scheme applied to the MBSFN data, the transmission timing, and the like.

(Step S25) The base station 100 transmits control information about the MBSFN to the mobile station 300 with the PMCH used for the CC of the MBSFN. This control information contains information that shows the modulation coding method and transmission timing. The mobile station 300 detects the PMCH and extracts control information that has been sent by the base station. Further, the base station 100 notifies the base station 200 of the same content as the control information.

(Step S26) The mobile station 300 performs setting of the mobile station 300 based on the control information on the MBSFN received by the base station 100 to enable reception of the MBMS data from the base stations 100 and 200.

(Step S27) The base station 100, 200 transmits the MBMS data that has been received by the SAE gateway 430 to the mobile station 300 in accordance with the scheduling result of the base station 100. The mobile station 300 synthesizes the received signals from the base stations 100 and 200 to extract the MBMS data.

As a result, the mobile station 300 requests the base station 100 to transmit the MBSFN when the service with the MBSFN transmission starts. At this time, the mobile station 300 judges from the notification information that the CC for MBSFN transmission can be transmitted, for example, the MBSFN request is transmitted with the determined CC. The base station 100 performs scheduling of the MBSFN as an MCE function. In this way, the base station 100 coordinates with the base station 200 to transmit MBMS data to the mobile station 300. Thereby, the reception quality of the mobile station 300 is improved.

Further, the mobile station 300 may indicate that the MBMS data is to be received by the MBSFN at the start of the service, and may not be explicitly stated. In other words, the "MBSFN request" transmitted by the mobile station 300 may be control information for explicitly requesting the MBSFN transmission, or may be a request for starting only a certain type of service. In the latter case, the base station 100 determines whether the service requested by the mobile station 300 is a service transmitted along with the MBSFN.

Fig. 16 is a view showing an example of allocation of a sub-frame for MBSFN. The base station 100 performs scheduling of radio resources as shown in FIG. 16, for example.

In this example, CC#1 belonging to 800 MHz and CC#2 to #5 belonging to 3.5 GHz are provided. Among CC#1 to #5, CC#1 is designated as a CC that can be used for MBSFN transmission. That is, the notification information notified by the E-PBCH (or other predetermined channel) includes information indicating CC#1 (for example, the ID of CC#1).

Also, in the DL radio frame of CC#1, the sub-frame #8 is designated as the MBSFN sub-frame. The sub frame #8 of CC#1 uses the extended CP, and the other sub frame uses the normal CP. Moreover, the number and location of the MBSFN sub-frames can be dynamically changed depending on the communication status of the mobile station connected to the base station 100.

Here, the non-MBSFN sub-frame can accommodate 10 mobile stations, and one of the 10 sub-frames included in the radio frame is designated as an MBSFN sub-frame. In addition, it is assumed that five mobile stations use MBSFN. In this case, the maximum number of mobile stations that can accommodate the MBSFN in CC#2 to #5 is 10×10=100. In addition, the maximum number of mobile stations that can accommodate MBSFN in CC#1 is 9×10=90, and five mobile stations using MBSFN can be accommodated. That is, in the example of Fig. 16, CC#1 to #5 can accommodate up to 495 mobile stations.

On the other hand, the base station 100 is not limited to a CC that can be used for MBSFN transmission, and is designed such that five mobile stations can utilize the MBSFN with an arbitrary CC. In particular, the case where the consideration is the worst is a case where CC#1 to #5 respectively accommodate the mobile station using MBSFN. In this case, the MBSFN sub-frame cannot accommodate the mobile station that is not transmitted by the MBSFN. Therefore, CC#1 to #5 can accommodate up to 9×10=90 mobile stations that are not transmitted by the MBSFN. In other words, CC#1 to #5 can accommodate up to 455 mobile stations.

In the above specific case, the utilization efficiency of (495-455) ÷ 455 × 100 = about 8.8% of radio resources is improved by limiting the state of the CC for MBSFN transmission to the unrestricted situation. In this way, the utilization efficiency of the radio resources can be improved by limiting the state of the CC that can be used for MBSFN transmission. Further, in the state where the MBSFN transmission is performed using the CC having the lowest frequency, the wireless signal including the MBMS data can be transmitted further. That is, the mobile station 300 can receive wireless signals including MBMS data from more base stations, and can further improve reception quality in a state in which more received signals are synthesized.

Fig. 17 is a diagram showing a calculation mode of the number of synthesis of MBSFN. Here, the mobile communication system has 37 partitions (partitions #1 to #37), and the mobile station 300 is located in the partition #1. Further, when communication is performed with a 3.5 GHz band, the wireless signal transmits a distance of one partition.

In this case, when communicating in the 3.5 GHz band, the mobile station 300 can receive the wireless signal of the partition #1 in the local area and the wireless signals adjacent to the six partitions (partitions #2 to #7) of the partition #1. On the other hand, when communicating in the 800 MHz band, the wireless signal can transmit a distance three times (e×p (4÷3.5)=about 3.14) when communicating with the 3.5 GHz band. That is, when communicating in the 800 MHz band, the mobile station 300 can receive the wireless signal of the local area #1 and the 36 sections (partitions #2 to #37) within three partition distances from the partition #1. .

That is, in the above specific example, when the mobile station 300 uses the MBSFN using the radio resources of the 3.5 GHz band, it is possible to synthesize the signals transmitted by the seven base stations and extract the MBMS data. On the other hand, when MBSFN is used using the radio resources of the 800 MHz band, the signals transmitted by the 37 base stations can be synthesized up to the maximum and the MBMS data can be extracted. In this way, in the state in which the MBMS data is received using the low-frequency radio resources, the reception quality of the mobile station can be further improved.

According to the mobile communication system according to the second embodiment, the base station 100 can limit the CCs that can be used for MBSFN transmission so that the radio resources used for MBSFN transmission are not dispersed in CC #1 to #5. Thereby, the utilization efficiency of the radio resources in the communication environment in which the normal data transmission and the MBSFN transmission are mixed can be improved.

Further, since the base station 100 notifies that the information for the CC for MBSFN transmission can be displayed, the mobile station 300 can efficiently perform the start processing of the service associated with the MBSFN transmission by referring to the notification information. Further, in the state where the base station 100 performs MBSFN transmission in CC#1 having the lowest frequency among CC#1 to #5, the reception quality of the mobile station 300 can be further improved.

Further, as described above, it is displayed that the information of the CC for MBSFN transmission can be notified by, for example, the extension notification channel. The extended notification channel can be used not only for information about the MBSFN, but also for transmitting various information for notification to the LTE-A mobile station. Such an "extended notification channel" may also be referred to as another name. For example, one of the conventional notification channel and the extended notification channel defined by LTE may be referred to as a first notification channel, and the other as a second notification channel.

[Third embodiment]

Next, a third embodiment will be described with reference to the drawings. The description is based on the difference from the second embodiment, and the description of the same matters as those of the second embodiment will be omitted. In the mobile communication system according to the third embodiment, when the CC currently used by the mobile station is different from the CC that can be used for MBSFN transmission, the CC to be used is switched. In the following description, "Hand Over" (HO: Hand Over) includes a switch between CCs belonging to different frequency bands and a switch between CCs belonging to the same frequency band.

The mobile communication system according to the third embodiment is realized by the same system configuration as the mobile communication system according to the second embodiment shown in Fig. 2. However, in the third embodiment, the base station 100 and the mobile station 300 described below are used instead of the base station 100 and the mobile station 300 of the second embodiment.

Fig. 18 is a block diagram showing a base station of the third embodiment. The base station 100a includes not only the modules included in the base station 100 shown in FIG. 12 but also the HO request extraction unit 124, the HO control unit 125, and the HO control information generation unit 126.

The HO request extracting unit 124 extracts the delivery request (HO request) transmitted from the mobile station 300a, that is, extracts control information indicating that the CC switching request is displayed. In this way, the extracted HO request is output to the HO control unit 125.

The HO control unit 125 receives the HO request extracted by the HO request extraction unit 124, and performs switching control of the CC to be used by the mobile station 300a. Further, the HO instruction control information generation unit 126 transmits a response to the HO request.

The HO control information generation unit 126 generates handover control information (HO control information) as a response to the HO request based on an instruction from the HO control unit 125. In this way, the generated HO control information is output to the mapping unit 121. The HO control information is mapped to the radio resource by the mapping unit 121.

Fig. 19 is a block diagram showing a mobile station according to the third embodiment. The mobile station 300a includes not only the modules included in the mobile station 300 shown in FIG. 13, but also the HO control information extracting unit 325, the HO control unit 326, and the HO request generating unit 327.

The HO control information extracting unit 325 extracts the HO control information transmitted from the base station 100a, that is, the mobile station 300a extracts control information as a response to the HO request transmitted to the base station 100a. In this way, the extracted HO control information is output to the HO control unit 326.

The HO control unit 326 controls the procedure of handover between CCs. Specifically, when the HO control unit 326 starts the service transmitted by the MBSFN, the HO control unit 326 refers to the notification information extracted by the MBSFN notification information extracting unit 318, and determines whether or not to perform the handover between the CCs. The mobile station 300a determines that the CC is currently handed over to the usable CC when the CC currently used for connection to the base station 100a is different from the CC that can be used for MBSFN transmission. When the handover is made, the HO request generation unit 327 is instructed to transmit the HO request.

Further, the HO control unit 326 executes the handover procedure based on the HO control information extracted by the HO control information extracting unit 325. Further, the terminal control unit 315 is instructed to switch the frequency band of the target of the wireless signal processing. Further, the handover between the CCs may be performed before the base station 100a transmits the MBSFN request, or may be performed after the transmission.

The HO request generating unit 327 generates control information capable of displaying the delivery request based on the instruction from the HO control unit 326, that is, generates an HO request. In this way, the generated HO request is output to the code modulation unit 323. Thereby, the HO request can be transmitted to the base station 100a.

Fig. 20 is a flow chart showing the processing of the mobile station in the third embodiment. Here, the situation in which the mobile station 300a transmits the MBSFN request to the base station 100a is considered. The difference from the mobile station processing of the second embodiment shown in Fig. 14 is that steps S131 to S133 described below are executed between step S13 and step S14.

(Step S131) The mobile station 300a determines whether or not the CC selected in step S13 is different from the CC currently used for connection to the base station 100a. At the same time, the process proceeds to step S132. When the same is the same, the process proceeds to step S14.

(Step S132) The mobile station 300a transmits the HO request for switching to the CC selected in step S13 to the base station 100a with the currently used CC.

(Step S133) Upon receiving the HO control information from the base station 100a as a response to the HO request, the mobile station 300a performs the handover of the CC currently used to the CC selected in step S13. Thereafter, the communication with the base station 100a is performed using the CC after the handover.

In this way, the mobile station 300a can know the CC that can be used for MBSFN transmission by referring to the notification information notified by the base station 100a. In this way, when the CC currently used is different from the CC that can be used, the handover between CCs is performed. Thereby, the mobile station 300a can smoothly and smoothly start the service transmitted by the MBSFN. Further, in the example of Fig. 20, the MBSFN request is transmitted after the handover is performed, however, as in the foregoing case, the MBSFN request may be transmitted before the handover is performed.

Fig. 21 is a sequence diagram showing an example of MBSFN control in the third embodiment. The sequence example of Fig. 21 shows a case where the MBSFN request is transmitted after the handover is performed. The difference from the sequence example of the second embodiment shown in Fig. 15 is that steps S221 to S223 described below are executed between step S22 and step S23.

(Step S221) The mobile station 300a transmits, to the base station 100a, the currently requested CC to display the HO request for the CC handover selected in step S22.

(Step S222) The base station 100a transmits the HO control information as a response to the HO request to the mobile station 300a with the currently used CC.

(Step S223) Handover is performed between the base station 100a and the mobile station 300a. That is, the CC to be used can be switched to the CC selected in step S22. Thereafter, the MBSFN request and the MBSFN control information are transmitted by the handed CC.

Fig. 22 is a sequence diagram showing another example of MBSFN control in the third embodiment. The sequence example of Fig. 22 shows a case where the MBSFN request is transmitted before the handover is performed. The difference from the sequence example of the second embodiment shown in Fig. 15 is that steps S231 to S233 described below are executed between step S23 and step S24.

The processing contents of steps S231 to S233 are the same as those of the above-described steps S221 to S223. Further, in the sequence example of Fig. 22, the MBSFN request from the mobile station 300a to the base station 100a is transmitted by the CC before handover, and the MBSFN control information transmitted from the base station 100a to the mobile station 300a is the CC after handover. To transfer.

According to the mobile communication system of the third embodiment, the same effects as those of the second embodiment can be obtained. Further, in the third embodiment, the mobile station 300a determines whether or not to perform handover between CCs by referring to the notification information. Therefore, even if the MBSFN transmission cannot be performed by the currently used CC, the mobile station 300a can smoothly and smoothly start the transmission with the MBSFN. Service.

[Fourth embodiment]

Next, a fourth embodiment will be described with reference to the drawings. The difference from the second and third embodiments will be mainly described, and the description of the same matters as those of the second and third embodiments will be omitted. In the mobile communication system according to the fourth embodiment, the base station does not have the MCE function (the function of controlling the MBSFN transmission), and the MME has the MCE function.

Fig. 23 is a view showing the mobile communication system of the fourth embodiment. The mobile communication system according to the fourth embodiment includes base stations 100b and 200b, a mobile station 300, and a core network 40a. The core network 40a is provided with an MME 410a, an MBMS gateway 420, and an SAE gateway 430.

The base stations 100b and 200b correspond to the base stations 100 and 200 of the second embodiment. However, the base stations 100b, 200b do not have MCE functions. That is, the base stations 100b and 200b transfer the MBSFN request received from the mobile station 300 to the MME 410a. Further, control information about the MBSFN is received from the MME 410a. The base stations 100b and 200b can be realized by the same configuration as the base station 100 shown in Fig. 12 except that the MCE function is not provided.

The MME 410a corresponds to the MME 410 of the second embodiment. However, the MME 410a has more functions of MCE. That is, the MME 410a receives the MBSFN request from the base stations 100b and 200b and schedules the MBSFN transmission. In this way, control information regarding the MBSFN request is transmitted to the base stations 100b, 200b.

Fig. 24 is a sequence diagram showing an example of the first MBSFN control in the fourth embodiment. The sequence example shown in Fig. 24 shows a case where the MME 410a transmits the MBSFN performed by the base stations 100b and 200b.

(Step S31) The base station 100b transmits the notification information on the PBCH. Also, the notification information about the MBSFN is transmitted in E-PBCH (or other predetermined channel). The mobile station 300 detects the PBCH and the E-PBCH (or other predetermined channel) and extracts the notification information transmitted by the base station 100b.

(Step S32) The mobile station 300 specifies a CC that can be used for MBSFN transmission in CC #1 to #5 in accordance with the notification information on the MBSFN. As such, the mobile station 300 selects the CC to receive the MBMS data.

(Step S33) The mobile station 300 transmits an MBSFN request to the base station 100b on the PUSCH of the selected CC (or the CC currently used by the mobile station 300). The base station 100b extracts the MBSFN request transmitted from the mobile station 300 and transfers it to the MME 410a. The MME 410a receives the MBSFN request forwarded by the base station 100b.

(Step S34) The MME 410a receives the MBSFN request transmitted from the mobile station 300 and performs control as an MCE. That is, the MME 410a performs scheduling to determine the range of the base station for performing MBSFN transmission, the modulation and coding scheme applied to the MBMS data, the transmission timing, and the like. Here, it is assumed that the base stations 100b and 200b perform MBSFN transmission.

(Step S35) The MME 410a transmits control information about the MBSFN to the base stations 100b and 200b. The base station 100b to which the mobile station 300 is now connected transmits control information on the MBSFN using the PMCH used for the CC transmitted by the MBSFN. The mobile station 300 detects the PMCH and extracts control information transmitted from the base station 100b.

(Step S36) The mobile station 300 performs setting of the mobile station 300 based on the control information on the MBSFN received by the base station so as to be able to receive the MBMS data from the base stations 100b and 200b.

(Step S37) The base stations 100b and 200b transmit the MBMS data received by the SAE gateway 430 to the mobile station 300 in the PMCH based on the control information received by the MME 410a. The mobile station 300 synthesizes the received signals from the base stations 100b and 200b and extracts the MBMS data.

As such, when the mobile station 300 transmits an MBSFN request, the MBSFN request is forwarded to the MME 410a. The ME 410a receives the MBSFN request and performs scheduling of MBSFN transmission, and causes the base stations 100b and 200b to perform MBSFN transmission.

Here, the sequence example of Fig. 24 shows a case where the handover between CCs is not performed as in the second embodiment. On the other hand, in the third embodiment, when the CC currently used is different from the CC that can be used for MBSFN transmission, handover between CCs can be performed. Hereinafter, the mobile station 300a described in the third embodiment will be described as an example of a procedure when the base station 100b transmits an MBSFN request. In this case, the base stations 100b and 200b can be realized by the same configuration as the base station 100a shown in Fig. 18.

Fig. 25 is a sequence diagram showing an example of the second MBSFN control in the fourth embodiment. The sequence example of Fig. 25 shows a case where the MBSFN request is transmitted after the handover is performed. The difference from the sequence example shown in Fig. 24 is that steps S321 to S323 described below are executed between step 32 and step S33.

(Step S321) The mobile station 300a transmits, to the base station 100b, the currently requested CC to display the HO request for the CC handover selected in step 32.

(Step S322) The base station 100b transmits the HO control information as a response to the HO request to the mobile station 300a with the currently used CC.

(Step S323) Handover is performed between the base station 100b and the mobile station 300a. That is, the CC to be used is switched to the CC selected in step S32. Thereafter, the MBSFN request and the MBSFN control information are transmitted between the base station 100b and the mobile station 300a by the delivered CC.

Fig. 26 is a sequence diagram showing an example of the third MBSFN control in the fourth embodiment. The sequence example of Fig. 26 shows a case where the MBSFN request is transmitted before the handover is performed. The difference from the sequence example shown in Fig. 24 is that steps S331 to S333 described below are executed between step S33 and step S34.

The processing contents of steps S331 to S333 are the same as the processing contents of steps S321 to S323 described above. Further, in the sequence example of Fig. 26, the MBSFN request from the mobile station 300a to the base station 100b is transmitted by the CC before handover, and the base station 100b can also forward the received MBSFN request to the MME 410a before the handover is performed. . The MBSFN control information transmitted from the base station 100b to the mobile station 300a is transmitted by the delivered CC.

According to the mobile communication system of the fourth embodiment, the same effects as those of the second or third embodiment can be obtained. Further, in the third embodiment, each base station can collectively perform control of MBSFN transmission on the core network 40a side without installing the MCE function.

Further, in the above description of the fourth embodiment, the MCE function is installed in the MME 410a. However, the MCE function may be installed in other devices in the core network 40a. Further, an independent device having MCE function can be provided inside or outside the core network 40a. In this case, the base stations 100a and 200b communicate with the independent device when performing MBSFN transmission.

Fig. 27 is a view showing a modification of the mobile communication system according to the fourth embodiment. The mobile communication system includes a base station 100b, 200b, a mobile station 300, and a core network 40b. The core network 40b is provided with an MME 410, an MBMS gateway 420, an SAE gateway 430, and an MCE 440.

The MCE 440 is a separate device that controls the transmission of MBSFN. The MCE 440 receives the MBSFN request from the base stations 100b and 200b to perform scheduling of MBSFN transmission. In this way, control information about the MBSFN is transmitted to the base stations 100b and 200b. In such a mobile communication system, the MCE 440 is executed instead of the processing executed by the MME 410a in the sequence example shown in Figs. 24 to 26 . In this way, an independent device having MCE function can be set in the mobile communication system.

Further, in the second to fourth embodiments, the MBSFN transmission has been described. However, the mobile communication systems according to the second to fourth embodiments can further perform MBMS transmission. The MBMS transmission is a transmission method of broadcasting/multicasting MBMS data in the same manner as MBSFN transmission. The difference between MBSFN transmission and MBMS transmission is as follows.

MBSFN transmits MBMS data at the same timing and using the same frequency and the same modulation method. The sub-frame used for MBSFN transmission is a different MBSFN sub-frame than the normal sub-frame, and the normal data and the MBMS data cannot be mixed in the same sub-frame. Moreover, the same schedule result can be applied to the plurality of base stations that perform MBSFN transmission. The mobile station receives MBMS data side by side from multiple base stations.

On the other hand, in the MBMS transmission, each base station individually sets the timing of transmitting the MBMS data, the frequency to be used, and the modulation method. Each base station performs scheduling of MBMS transmission. The normal sub-frame can be used for MBMS transmission, so that the normal data and the MBMS data can be mixed in the same sub-frame. The mobile station receives MBMS data from a single base station.

In this way, when the MBMS is transmitted, the base station can schedule the state in which the normal data and the MBMS data are mixed. That is, the transmission channel that transmits the normal data, that is, the downlink shared channel (DL-SCH), and the transmission channel that transmits the MBMS data, that is, the multicast channel (MCH) can be mapped to the downlink shared physical channel (PDSCH). . By using MBMS transmission, it is possible to easily provide a service of a local type (for example, information of a type of a specific place).

Further, in the MBMS transmission, since both the normal data and the MBMS data can be accommodated in the same sub-frame, even when the MBMS transmission is performed in parallel with the plurality of CCs, the scheduling can be performed without reducing the utilization efficiency of the radio resources.

The above description is merely illustrative of the principles of the invention. The present invention is not limited to the precise configuration and application examples described and illustrated in the above description, and all corresponding modifications and equivalents may be regarded as additional patent claims and The scope of the invention consisting of equals.

1, 2. . . Base station

1a. . . Production department

1b. . . Sending department

3. . . Mobile station

3a. . . Receiving department

3b. . . Control department

40, 40a, 40b. . . Core network

100, 200. . . Base station

100a, 100b, 200a, 200b. . . Base station

111. . . Transmit receiving antenna

112. . . Wireless receiving unit

113. . . Demodulation and decoding unit

114. . . Quality Information Generation Department

115. . . MBSFN requires the extraction department

116. . . Scheduler

117. . . Notification information generation department

118. . . MBSFN Notification Information Generation Department

119. . . MBSFN Control Information Generation Department

120. . . RS generation unit 120

121. . . Mapping unit 121

122. . . Code modulation department

123. . . Wireless transmission unit

124. . . HO requires the withdrawal department

125. . . HO Control Department

126. . . HO Control Information Generation Department

300, 300a. . . Mobile station

311. . . Transmit receiving antenna

312. . . Wireless receiving unit

313. . . Demodulation and decoding unit

314. . . Notification information extraction department

315. . . Terminal control department

316. . . MBSFN Control Information Extractor

317. . . MBSFN Control Department

318. . . MBSFN notification information extraction department

319. . . MBSFN Requirements Generation Department

320. . . RS extraction department

321. . . Quality measurement department

322. . . Quality Information Generation Department

323. . . Code modulation department

324. . . Wireless transmission unit

325. . . HO control information extraction department

326. . . HO Control Department

327. . . HO requirements generation department

410, 410a. . . MME

420. . . MBMS gateway

430. . . SAE gateway

440. . . MCE

CC#1~CC#5. . . Carrier component

P-SCH. . . Primary sync channel

S-SCH. . . Secondary sync channel

PBCH. . . Entity notification channel

E-PBCH. . . Extended entity notification channel

PDCCH. . . Downlink entity control channel

S11 to S16, S21 to S27, S31 to S37, S131 to S133, S221 to S223, S231 to S233, S321 to S323, and S331 to S333. . . step

Fig. 1 is a view showing a mobile communication system according to the first embodiment.

Fig. 2 is a view showing the mobile communication system of the second embodiment.

Fig. 3 is a diagram showing a setting example of a carrier component.

Fig. 4 is a diagram showing a first example of carrier aggregation.

Fig. 5 is a diagram showing a second example of carrier aggregation.

Figure 6 is a diagram showing an example of spectrum aggregation.

Fig. 7 is a view showing a configuration example of a radio frame.

Fig. 8 is a diagram showing a first allocation example of the extended entity notification channel.

Fig. 9 is a diagram showing a second allocation example of the extended entity notification channel.

Fig. 10 is a diagram showing a third allocation example of the extended entity notification channel.

Fig. 11 is a diagram showing a structural example of a symbol.

Fig. 12 is a block diagram showing a base station of the second embodiment.

Fig. 13 is a block diagram showing a mobile station according to the second embodiment.

Fig. 14 is a flow chart showing the processing of the mobile station in the second embodiment.

Fig. 15 is a sequence diagram showing an example of MBSFN control in the second embodiment.

Fig. 16 is a view showing an example of allocation of a sub-frame for MBSFN.

Fig. 17 is a diagram showing a calculation mode of the number of synthesis of MBSFN.

Fig. 18 is a block diagram showing a base station of the third embodiment.

Fig. 19 is a block diagram showing a mobile station according to the third embodiment.

Fig. 20 is a flow chart showing the processing of the mobile station in the third embodiment.

Fig. 21 is a sequence diagram showing an example of MBSFN control in the third embodiment.

Fig. 22 is a sequence diagram showing another example of MBSFN control in the third embodiment.

Fig. 23 is a view showing the mobile communication system of the fourth embodiment.

Fig. 24 is a sequence diagram showing an example of the first MBSFN control in the fourth embodiment.

Fig. 25 is a sequence diagram showing an example of the second MBSFN control in the fourth embodiment.

Fig. 26 is a sequence diagram showing an example of the third MBSFN control in the fourth embodiment.

Fig. 27 is a view showing a modification of the mobile communication system according to the fourth embodiment.

1, 2. . . Base station

1a. . . Production department

1b. . . Sending department

3. . . Mobile station

3a. . . Receiving department

3b. . . Control department

Claims (11)

A mobile communication system, comprising: a base station including a generating unit and a generating unit; wherein the generating unit generates notification information, and the notification information can be used in a plurality of frequency bands that can be used for wireless communication, and is used in a frequency band that transmits data of the same content at the same time sequence as the other base stations; the transmitting unit notifies the notification information by wireless; and the mobile station includes a receiving unit and a control unit: the receiving unit receives The notification information notified by the base station; the control unit controls, according to the notification information, a processor that receives data of the same content transmitted by the base station and the other base stations at the same timing. The mobile communication system according to claim 1, wherein the control unit switches the frequency band to be used when the frequency band indicated by the notification information is different from the frequency band used by the mobile station to connect to the base station. The mobile communication system according to claim 2, wherein the control unit requests the base station to transmit data of the same content at the same timing by using the radio resource corresponding to the switched frequency band after performing the handover. The mobile communication system according to claim 2, wherein the control unit requests the base station to transmit data of the same content at the same timing by using a radio resource corresponding to the frequency band before the handover, and then performs the switching. The mobile communication system according to claim 1, wherein the transmitting unit transmits, by the first notification channel, information used by the mobile station to be connected to the base station, and a second notification channel different from the first notification channel. Send the aforementioned notification information. The mobile communication system of claim 5, wherein the first notification channel is a channel received by the first and second types of mobile stations, and the second notification channel is a channel received by the second type of mobile station, the action Taiwan's second type of mobile station. The mobile communication system of claim 1, wherein the transmitting unit transmits the notification information by using a control channel that transmits control information, and the control information is used by the mobile station to receive data of the same content transmitted at the same time sequence. The processor. The mobile communication system of claim 1, wherein at least the lowest frequency band of the plurality of frequency bands is used for transmitting the same content at the same timing as the other base stations. A base station is a wireless communicator that is connected to a mobile station that can receive data of the same content transmitted by a plurality of base stations at the same time sequence, and is characterized in that: a generating unit generates notification information, and the notification information can display wireless communication. Among the plurality of usable frequency bands, the frequency band used for transmitting the same content data at the same timing as the other base stations; and the transmitting unit wirelessly notifying the notification information generated by the generating unit. A mobile station that performs wireless communication with the first and second base stations, and includes a receiving unit that receives notification information by the first base station, and the notification information can display a plurality of wireless communication usable In the frequency band, the frequency band used to transmit the same content data to the second base station at the same timing; and the control unit controls the reception of the first base and the second base based on the notification information received by the receiving unit A processor that transmits data of the same content at the same time. A wireless communication method is a wireless communication method including a mobile communication system between a first base station and a second base station, and the mobile station includes the following steps: the first base station generates notification information, and the notification information can display wireless communication. a frequency band used for transmitting data of the same content at the same timing as the second base station, wherein the first base station wirelessly notifies the notification information; and the mobile station receives the aforementioned notification by the first base station Notification information; and the mobile station receives data of the same content transmitted by the first base station and the second base station at the same time sequence based on the received notification information.