JP6297116B2 - Mobile communication system, base station and mobile terminal - Google Patents

Description

  The present invention relates to a mobile communication system in which a base station performs radio communication with a plurality of mobile terminals, and a base station and a mobile terminal in the mobile communication system.

  Among the communication systems called the third generation, the W-CDMA (Wideband Code division Multiple Access) system has been commercialized in Japan since 2001. Also, by adding a packet transmission channel (HS-DSCH: High Speed-Downlink Shared Channel) to the downlink (dedicated data channel, dedicated control channel), further speeding up data transmission using the downlink Realized HSDPA (High Speed Down Link Packet Access) service has been started. Furthermore, in order to further increase the speed of data transmission in the uplink direction, a service has also started for the HSUPA (High Speed Up Link Packet Access) method. W-CDMA is a communication system defined by 3GPP (3rd Generation Partnership Project), which is a standardization organization for mobile communication systems, and has compiled release 8 standards.

  In 3GPP, as a communication method different from W-CDMA, “Long Term Evolution LTE” for the radio section and the entire system configuration including the core network (also simply referred to as network) are “System”. A new communication method called "Architecture Evolution SAE" is being studied. In LTE, the access scheme, radio channel configuration and protocol are completely different from those of the current W-CDMA (HSDPA / HSUPA). For example, while W-CDMA uses Code Division Multiple Access, W-CDMA uses OFDM (Orthogonal Frequency Division Multiplexing) in the downlink direction and SC-FDMA (Single in the uplink direction). Career Frequency Division Multiple Access) is used. The bandwidth is selectable for each base station within 1.4 / 3/5/10/15/20 MHz in LTE, whereas W-CDMA is 5 MHz. Also, LTE does not include circuit switching as in W-CDMA, and is only a packet communication system.

  LTE is defined as an independent radio access network different from the W-CDMA network because the communication system is configured using a new core network different from the W-CDMA core network (GPRS). Therefore, in order to distinguish from a W-CDMA communication system, in an LTE communication system, a base station (Base station) that communicates with a mobile terminal (UE: User Equipment) is an eNB (E-UTRAN NodeB), and a plurality of base stations. A base station controller (Radio Network Controller) that exchanges control data and user data with each other is called an EPC (Evolved Packet Core) (sometimes called an aGW: Access Gateway). In the LTE communication system, a unicast service and an E-MBMS service (Evolved Multimedia Broadcast Multicast Service) are provided. The E-MBMS service is a broadcast-type multimedia service and may be simply referred to as MBMS. Mass broadcast contents such as news, weather forecasts, and mobile broadcasts are transmitted to a plurality of mobile terminals. This is also called a point-to-multipoint service.

  Non-Patent Document 1 describes the current decisions regarding the overall architecture of the LTE system in 3GPP. The overall architecture (Chapter 4 of Non-Patent Document 1) will be described with reference to FIG. FIG. 1 is an explanatory diagram illustrating a configuration of an LTE communication system. In FIG. 1, a control protocol (for example, RRC (Radio Resource Management)) and a user plane (for example, PDCP: Packet Data Convergence Protocol, RLC: Radio Link Control, MAC: Medium Access Control, PHY: Physical layer) for the mobile terminal 101 are based. If terminated at station 102, Evolved Universal Terrestrial Radio Access (E-UTRAN) is composed of one or more base stations 102. The base station 102 performs scheduling (Scheduling) and transmission of a paging signal (also referred to as a paging message or paging message) notified from the MME 103 (Mobility Management Entity). Base stations 102 are connected to each other via an X2 interface. The base station 102 is connected to the EPC (Evolved Packet Core) via the S1 interface. More specifically, the base station 102 is connected to the MME 103 (Mobility Management Entity) via the S1_MME interface, and is connected to the S-GW 104 (Serving Gateway) via the S1_U interface. The The MME 103 distributes the paging signal to a plurality or a single base station 102. Further, the MME 103 performs mobility control (Mobility control) in an idle state. The MME 103 manages a tracking area list when the mobile terminal is in a standby state and an active state. The S-GW 104 transmits / receives user data to / from one or a plurality of base stations 102. The S-GW 104 becomes a local mobility anchor point at the time of handover between base stations. Further, there is a P-GW (PDN Gateway), which performs packet filtering and UE-ID address allocation for each user.

  Non-Patent Document 1 (Chapter 5) describes the current decisions regarding the frame configuration in the LTE system in 3GPP. This will be described with reference to FIG. FIG. 2 is an explanatory diagram showing a configuration of a radio frame used in the LTE communication system. In FIG. 2, one radio frame is 10 ms. The radio frame is divided into 10 equally sized sub-frames. The subframe is divided into two equally sized slots. A downlink synchronization signal (Downlink Synchronization Signal: SS) is included in the first (# 0) and sixth (# 5) subframes for each frame. There are a first synchronization signal (Primary Synchronization Signal: P-SS) and a second synchronization signal (Secondary Synchronization Signal: S-SS). Channels other than MBSFN (Multimedia Broadcast multicast service Single Frequency Network) and channels other than MBSFN are multiplexed on a subframe basis. Hereinafter, a subframe for MBSFN transmission is referred to as an MBSFN sub-frame. Non-Patent Document 2 describes a signaling example at the time of MBSFN subframe allocation. FIG. 3 is an explanatory diagram showing the configuration of the MBSFN frame. In FIG. 3, an MBSFN subframe is allocated for each MBSFN frame (MBSFN frame). A set of MBSFN frames (MBSFN frame Cluster) is scheduled. A repetition period (Repetition Period) of a set of MBSFN frames is assigned.

  Non-Patent Document 1 describes the current decisions regarding the channel configuration in the LTE system in 3GPP. It is assumed that the same channel configuration as that of the non-CSG cell is used also in a CSG (Closed Subscriber Group cell) cell. A physical channel (Chapter 5 of Non-Patent Document 1) will be described with reference to FIG. FIG. 4 is an explanatory diagram illustrating physical channels used in the LTE communication system. In FIG. 4, a physical broadcast channel 401 (Physical Broadcast channel: PBCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. A BCH transport block is mapped to four subframes in a 40 ms interval. There is no obvious signaling of 40ms timing. A physical control format indicator channel 402 (Physical Control format indicator channel: PCFICH) is transmitted from the base station 102 to the mobile terminal 101. PCFICH notifies base station 102 to mobile terminal 101 about the number of OFDM symbols used for PDCCHs. PCFICH is transmitted for each subframe. A physical downlink control channel 403 (Physical downlink control channel: PDCCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. The PDCCH includes resource allocation, HARQ information related to DL-SCH (a downlink shared channel that is one of the transport channels shown in FIG. 5), and PCH (paging that is one of the transport channels shown in FIG. 5). Channel). The PDCCH carries an Uplink Scheduling Grant. The PDCCH carries ACK / Nack that is a response signal for uplink transmission. The PDCCH is also called an L1 / L2 control signal. A physical downlink shared channel 404 (PDSCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. PDSCH is mapped with DL-SCH (downlink shared channel) which is a transport channel and PCH which is a transport channel. A physical multicast channel 405 (Physical multicast channel: PMCH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. PMCH is mapped with MCH (multicast channel) which is a transport channel.

  A physical uplink control channel 406 (Physical Uplink control channel: PUCCH) is an uplink channel transmitted from the mobile terminal 101 to the base station 102. The PUCCH carries ACK / Nack which is a response signal (response) to downlink transmission. PUCCH carries a CQI (Channel Quality Indicator) report. CQI is quality information indicating the quality of received data or channel quality. The PUCCH carries a scheduling request (SR). A physical uplink shared channel 407 (Physical Uplink shared channel: PUSCH) is an uplink channel transmitted from the mobile terminal 101 to the base station 102. PUSCH is mapped with UL-SCH (uplink shared channel which is one of the transport channels shown in FIG. 5). A physical HARQ indicator channel 408 (Physical Hybrid ARQ indicator channel: PHICH) is a downlink channel transmitted from the base station 102 to the mobile terminal 101. The PHICH carries ACK / Nack that is a response to uplink transmission. A physical random access channel 409 (Physical random access channel: PRACH) is an uplink channel transmitted from the mobile terminal 101 to the base station 102. The PRACH carries a random access preamble.

  As the downlink reference signal, a symbol known as a mobile communication system is inserted into the first, third and last OFDM symbols of each slot. As a measurement of the physical layer of the mobile terminal, there is a reference symbol received power (RSRP).

  A transport channel (Chapter 5 of Non-Patent Document 1) will be described with reference to FIG. FIG. 5 is an explanatory diagram for explaining a transport channel used in an LTE communication system. FIG. 5A shows mapping between the downlink transport channel and the downlink physical channel. FIG. 5B shows mapping between the uplink transport channel and the uplink physical channel. For the downlink transport channel, a broadcast channel (BCH) is broadcast to the entire base station (cell). BCH is mapped to the physical broadcast channel (PBCH). Retransmission control by HARQ (Hybrid ARQ) is applied to the downlink shared channel (DL-SCH). Broadcasting to the entire base station (cell) is possible. Supports dynamic or semi-static resource allocation. Quasi-static resource allocation is also called Persistent Scheduling. In order to reduce power consumption of the mobile terminal, DRX (Discontinuous reception) of the mobile terminal is supported. DL-SCH is mapped to a physical downlink shared channel (PDSCH). A paging channel (Paging channel: PCH) supports DRX of the mobile terminal in order to enable low power consumption of the mobile terminal. Notification to the entire base station (cell) is required. It is mapped to a physical resource such as a physical downlink shared channel (PDSCH) that can be dynamically used for traffic, or a physical resource such as a physical downlink control channel (PDCCH) of another control channel. A multicast channel (Multicast channel: MCH) is used for broadcast to the entire base station (cell). Supports SFN combining of MBMS services (MTCH and MCCH) in multi-cell transmission. Supports quasi-static resource allocation. MCH is mapped to PMCH.

  Retransmission control by HARQ (Hybrid ARQ) is applied to the uplink shared channel (UL-SCH). Supports dynamic or semi-static resource allocation. UL-SCH is mapped to a physical uplink shared channel (PUSCH). The random access channel (Random access channel: RACH) shown in FIG. 5B is limited to control information. There is a risk of collision. The RACH is mapped to a physical random access channel (PRACH). HARQ will be described.

  HARQ is a technique for improving the communication quality of a transmission path by combining automatic repeat request and error correction (forward error correction). There is also an advantage that error correction functions effectively by retransmission even for a transmission path in which communication quality changes. In particular, further quality improvement can be obtained by combining the reception result of the initial transmission and the reception result of the retransmission upon retransmission. An example of the retransmission method will be described. When the reception data cannot be decoded correctly on the receiving side (when a CRC Cyclic Redundancy Check error occurs (CRC = NG)), “Nack” is transmitted from the receiving side to the transmitting side. The transmission side that has received “Nack” retransmits the data. When the reception data can be correctly decoded on the reception side (when no CRC error occurs (CRC = OK)), “Ack” is transmitted from the reception side to the transmission side. The transmitting side that has received “Ack” transmits the next data. An example of the HARQ method is “Chase Combining”. Chase combining is a method in which the same data sequence is transmitted for initial transmission and retransmission, and the gain is improved by combining the initial transmission data sequence and the retransmission data sequence in retransmission. The idea is that even if there is an error in the initial transmission data, it is partially accurate, and it is possible to transmit data with higher accuracy by combining the initial transmission data and the retransmission data of the correct part. Based on. Another example of the HARQ scheme is IR (Incremental Redundancy). IR is to increase the redundancy. By transmitting parity bits in retransmission, the redundancy is increased in combination with the initial transmission, and the quality is improved by the error correction function.

  The logical channel (Chapter 6 of Non-Patent Document 1) will be described with reference to FIG. FIG. 6 is an explanatory diagram illustrating logical channels used in the LTE communication system. FIG. 6A shows mapping between the downlink logical channel and the downlink transport channel. FIG. 6B shows mapping between the uplink logical channel and the uplink transport channel. A broadcast control channel (BCCH) is a downlink channel for broadcast system control information. The BCCH that is a logical channel is mapped to a broadcast channel (BCH) that is a transport channel or a downlink shared channel (DL-SCH). A paging control channel (Paging control channel: PCCH) is a downlink channel for transmitting a paging signal. PCCH is used when the network does not know the cell location of the mobile terminal. The PCCH that is a logical channel is mapped to a paging channel (PCH) that is a transport channel. The common control channel (CCCH) is a channel for transmission control information between the mobile terminal and the base station. CCCH is used when the mobile terminal does not have an RRC connection with the network. In the downlink method, CCCH is mapped to a downlink shared channel (DL-SCH) that is a transport channel. In the uplink direction, the CCCH is mapped to an uplink shared channel (UL-SCH) that is a transport channel.

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

  GCI is a global cell identity. A CSG cell (Closed Subscriber Group cell) is introduced in LTE and UMTS (Universal Mobile Telecommunication System). CSG will be described below (Chapter 3.1 of Non-Patent Document 7). A CSG (Closed Subscriber Group) is a cell in which an operator identifies an available subscriber (a cell for a specific subscriber). The identified subscriber is allowed to access one or more E-UTRAN cells of the Public Land Mobile Network (PLMN). One or more E-UTRAN cells to which the identified subscribers are allowed access are referred to as “CSG cell (s)”. However, PLMN has access restrictions. A CSG cell is a part of a PLMN that broadcasts a unique CSG identity (CSG identity: CSG ID, CSG-ID). Members of the subscriber group who have been registered for use in advance and access the CSG cell using the CSG-ID that is the access permission information. The CSG-ID is broadcast by the CSG cell or the cell. There are a plurality of CSG-IDs in a mobile communication system. The CSG-ID is then used by the terminal (UE) to facilitate access of CSG related members. It has been discussed at the 3GPP meeting that a CSG cell or information broadcast by the cell is made a tracking area code (TAC) instead of a CSG-ID. The location tracking of a mobile terminal is performed in units of areas composed of one or more cells. The position tracking is to enable tracking of the position of the mobile terminal and calling (the mobile terminal receives a call) even when communication is not performed (standby state). This area for tracking the location of the mobile terminal is called a tracking area. The CSG white list is a list stored in the USIM in which all CSG IDs of the CSG cells to which the subscriber belongs are recorded. The white list in the mobile terminal is given by the upper layer. Thereby, the base station of the CSG cell allocates radio resources to the mobile terminal.

  A “suitable cell” will be described below (Chapter 4.3 of Non-Patent Document 7). A “suitable cell” is a cell in which the UE camps on to receive normal service. Such a cell was provided by (1) the non-access stratum (2) the (1) the cell is the selected or registered PLMN, or part of the PLMN in the “Equivalent PLMN list” The latest information must satisfy the following conditions. (1) The cell is not a barred cell. (2) The cell is not part of the “prohibited LAs for roaming” list, but part of at least one tracking area (TA). In that case, the cell needs to satisfy the above (1), (3) that the cell satisfies the cell selection evaluation criteria, and (4) the system information (System Information: SI) as the CSG cell. ), The CSG-ID is part of the UE's “CSG WhiteList” (included in the UE's CSG WhiteList).

  An “acceptable cell” will be described below (Chapter 4.3 of Non-Patent Document 7). This is a cell where a UE camps on in order to receive a limited service (emergency call). Such a cell shall meet all the following requirements: That is, the minimum set of requirements for initiating an emergency call in an E-UTRAN network is shown below. (1) The cell is not a barred cell. (2) The cell satisfies the cell selection evaluation criteria.

  Camping on a cell is a state in which the UE has completed cell selection / reselection processing and the UE has selected a cell for monitoring system information and paging information.

3GPP TS36.300 V8.6.0 3GPP R1-072963 3GPP TR R3.020 V0.6.0 3GPP R2-082899 3GPP R2-083494 3GPP TS36.331 V8.3.0 3GPP TS36.304 V8.3.0 3GPP R2-084346 3GPP S1-083461 3GPP R2-093950 3GPP R2-093864 3GPP R2-093138 3GPP TS 36.213 3GPP TS36.101

  Many CSG (Closed Subscriber Group cell) cells are required to be installed in apartments, schools, companies, and the like. For example, a usage method is required in which a CSG cell is installed for each room in an apartment, for each classroom in a school, and for each section in a company, and only a user registered in each CSG cell can use the CSG cell. Furthermore, the CSG cell is assumed to have a portable size and weight, and installation and removal of these CSG cells are required to be performed frequently and flexibly. Considering such a request, radio waves from many CSG cells are simultaneously transmitted at a certain point. That is, in a condominium, a school, a company, etc., a situation occurs in which the mobile terminal is in a position where radio waves from a large number of CSG cells reach.

  In addition, the CSG cell is installed in a place where radio waves from the non-CSG cell do not reach and is required to be able to communicate with the mobile terminal via the CSG cell. For example, at present, there are many situations where an apartment room does not receive radio waves from a non-CSG cell. In such a case, a CSG cell is installed for each room in the apartment, and each CSG is configured with a CSG cell for each room, and a CSG-ID is given. For example, a mobile terminal owned by a resident in each room may be registered for user access to the CSG cell in each room. In such a situation, the mobile terminal does not receive radio waves from the non-CSG cell, and exists in a place where radio waves from many CSG cells can reach. In such a case, depending on the radio wave propagation environment, radio waves from the CSG cell registered for user access may not reach the mobile terminal, or even if received, the received power may be weaker than other CSG cells. To do.

  As described above, in the case of a mobile terminal in a position where radio waves from a large number of CSG cells reach, a situation where a number of inaccessible CSG cells (that is, CSG cells that are not registered for user access) are repeatedly searched and selected repeatedly Occurs. In such a case, control delay, radio resource usage efficiency, and signaling efficiency decrease in the system. Further, there arises a problem that power consumption of a mobile terminal that repeats cell search increases. These problems become important when assuming the future arrangement of CSG cells as described above. The present invention has been made to solve these problems.

A mobile communication system according to the present invention is a mobile communication system including a mobile terminal and a base station that performs wireless communication with the mobile terminal, and a cell to which a specified subscriber is permitted access ( the range of identification codes assigned to the CSG cell) (CSG-ID), all SANYO notify the mobile terminal from the base station, the range of identification codes (CSG-ID) is different from the frequency layer in which the CSG cell belongs It is the range of CSG-ID regarding another frequency layer .

The base station according to the present invention is a base station that performs radio communication with a mobile terminal, and an identification code (CSG-ID) assigned to a cell (CSG cell) to which the specified subscriber is allowed to access. the range) state, and are not to be notified to the mobile terminal, the range of identification codes (CSG-ID) is the frequency layer that CSG cell belongs is in the range of CSG-ID for different other frequency layer.

A mobile terminal according to the present invention is a mobile terminal that performs radio communication with a base station, and an identification code (CSG-ID) assigned to a cell (CSG cell) to which a specified subscriber is allowed access. the range) state, and are not received from the base station, the range of identification codes (CSG-ID) is the frequency layer that CSG cell belongs is in the range of CSG-ID for different other frequency layer.

  The mobile communication system according to the present invention includes a mobile terminal and a base station that performs wireless communication with the mobile terminal. The range of the identification code (CSG-ID) assigned to the cell (CSG cell) to which the identified subscriber is permitted to access is notified from the base station to the mobile terminal. As a result, it is possible to prevent the mobile terminal from searching for the CSG cell in vain.

  The base station according to the present invention is a base station that performs wireless communication with a mobile terminal. The base station notifies the mobile terminal of the range of identification codes (CSG-ID) assigned to the cell (CSG cell) to which the specified subscriber is permitted to access. As a result, it is possible to prevent the mobile terminal from searching for the CSG cell in vain.

  The mobile terminal according to the present invention is a mobile terminal that performs wireless communication with a base station. The mobile terminal receives from the base station a range of identification codes (CSG-ID) assigned to the cell (CSG cell) to which the identified subscriber is allowed access. As a result, it is possible to prevent the mobile terminal from searching for the CSG cell in vain.

It is explanatory drawing which shows the structure of the communication system of a LTE system. It is explanatory drawing which shows the structure of the communication system of a LTE system. FIG. 2 is an explanatory diagram showing a configuration of a radio frame used in an LTE communication system. It is explanatory drawing which shows the structure of a MBSFN (Multimedia Broadcast multicast service Single Frequency Network) frame. It is explanatory drawing explaining the physical channel used with the communication system of a LTE system. It is explanatory drawing explaining the transport channel used with the communication system of a LTE system. It is explanatory drawing explaining the logical channel used with the communication system of a LTE system. It is a block diagram which shows the whole structure of the mobile communication system currently discussed by 3GPP. It is a block diagram which shows the structure of the mobile terminal 311 which concerns on this invention. It is a block diagram which shows the structure of the base station 312 which concerns on this invention. It is a block diagram which shows the structure of MME which concerns on this invention. It is a block diagram which shows the structure of HeNBGW which concerns on this invention. It is a flowchart which shows the outline of the cell search which a mobile terminal (UE) performs in the communication system of a LTE system. It is a cell conceptual diagram in case many CSG cells exist. It is a flowchart of the cell search of the mobile terminal in the position where the electromagnetic waves from many Home-eNBs reach. 6 is a sequence diagram for reporting PCI split information according to Embodiment 1. FIG. 3 is a flowchart of cell search of a mobile terminal in the first embodiment. FIG. 11 is a sequence diagram for reporting PCI split information in Modification 1 of Embodiment 1. It is a sequence diagram which alert | reports the PCI split information of another frequency layer. It is a figure which shows the case where Home-eNB exists in the area of eNB. FIG. 3 is a sequence diagram of a method for notifying a white list through a non-CSG cell, which is discussed in 3GPP. It is a figure which shows the case where the Home-eNB (CSG cell) which the mobile terminal registered becomes outside the area of a non-CSG cell. FIG. 10 is a sequence diagram when a mobile terminal that does not have a white list in the third embodiment starts manual search. It is a figure which shows the case where a mobile terminal is not under the control of a non-CSG cell but under the control of many CSG cells. FIG. 10 is a sequence diagram when a manual search is performed in the fourth embodiment. FIG. 6 is a sequence diagram of a method for transmitting a white list message before transmitting a TAU reject. FIG. 10 is a sequence diagram in the method disclosed in the first modification of the fifth embodiment. FIG. 10 is a sequence diagram of a method for prohibiting a mobile terminal from establishing an RRC connection to a cell when a TAU reject message is received once from the same cell. It is a figure which shows the process in the mobile terminal at the time of providing a timer. FIG. 24 is a sequence diagram of a method for transmitting a white list registration message before transmitting an nth TAU reject message in the seventh embodiment. FIG. 10 is a sequence diagram of a method in which a mobile terminal prohibits an RRC connection request to a cell when an RRC connection reject message is received once from the same cell. It is a sequence diagram of a method in which a CSG cell belonging to a CSG-ID to which a user equipment has not been registered for user access transmits a whitelist registration message before transmitting an RRC connection reject message. FIG. 38 is a sequence diagram of a method for returning an Ack / Nack indicating success / failure of whitelist (update) message reception in the eleventh embodiment. It is a flowchart which shows the process of the mobile terminal concerning RRC connection re-establishment. It is a flowchart which shows the process of the mobile terminal concerning RRC connection re-establishment at the time of introduce | transducing a CSG cell. It is a flowchart which shows the process of the mobile terminal concerning the RRC connection re-establishment when the timer of the allowable time until selecting the cell in E-UTRA is separately provided with the white list useful and the white list useless. It is a flowchart which shows the process of the mobile terminal concerning RRC connection reset when notifying the timer useful for a white list from a CSG cell. It is a flowchart which shows the process of the mobile terminal concerning RRC connection reset when notifying the timer useful for a white list from a CSG cell. It is a flowchart which shows the process of the mobile terminal regarding the priority of a prior art. It is a flowchart which shows the process of the mobile terminal at the time of providing the priority with a white list useful and white list useless separately. It is a flowchart which shows the process of the mobile terminal at the time of providing the effective time of a priority separately for white list usefulness and white list uselessness. It is a flowchart which shows the process of the mobile terminal in the cell reselection procedure of a prior art. It is a flowchart which shows the process of the mobile terminal in the cell reselection procedure using the period which performs the measurement for cell reselection, even if the mobile terminal which has CSG-ID in a white list is a case where the state of a serving cell is good. The flowchart which shows the process of the mobile terminal in the cell reselection procedure which uses the period and offset value which perform the measurement for cell reselection, even if the mobile terminal which has CSG-ID in a white list is in a good serving cell state It is. The mobile terminal having a CSG-ID in the white list cancels the period for performing measurement for cell reselection and the period for performing measurement when cell reselection cannot be performed even when the serving cell state is good It is a flowchart which shows the process of the mobile terminal in a cell reselection procedure. The flowchart which shows the process of the mobile terminal in the cell reselection procedure using the measurement reference | standard for the mobile terminal which has CSG-ID in a white list to start cell reselection for the mobile terminal which has CSG-ID in a white list It is. It is a flowchart which shows the process of the mobile terminal at the time of providing the offset separately for UE which has CSG-ID in the white list, and the UE which is not so, and making the reselection procedure to a hybrid cell different. It is a flowchart which shows the cell reselection procedure process of the mobile terminal at the time of combining Embodiment 15 and the method of providing an offset separately. It is a flowchart which shows the cell reselection procedure process of the mobile terminal at the time of providing offset separately in order to make it difficult to perform cell reselection from a hybrid cell. It is a conceptual diagram at the time of making UE of a CSG member stay longer than UE of a non-CSG member in a hybrid cell. It is an example of a procedure until PRACH initial transmission in a hybrid cell. It is the procedure outline | summary to PRACH initial transmission in a hybrid cell in the case of using the difference of a cell reselection threshold value.

Embodiment 1 FIG.
FIG. 7 is a block diagram showing the overall configuration of an LTE mobile communication system currently under discussion in 3GPP. Currently, in 3GPP, CSG (Closed Subscriber Group) cells (e-UTRAN Home-eNodeB (Home-eNB, HeNB), UTRAN Home-NB (HNB)) and non-CSG cells (e-UTRAN eNodeB (eNB) ), UTRAN NodeB (NB), GERAN BSS) and other systems are being studied. For e-UTRAN, configurations such as (a) and (b) in FIG. It has been proposed (Non-Patent Document 1, Non-Patent Document 3). FIG. 7A will be described. A mobile terminal (UE) 71 performs transmission / reception with the base station 72. The base station 72 is classified into an eNB (non-CSG cell) 72-1 and a Home-eNB (CSG cell) 72-2. The eNB 72-1 is connected to the MME 73 via the interface S1, and control information is communicated between the eNB and the MME. A plurality of MMEs are connected to one eNB. The Home-eNB 72-2 is connected to the MME 73 via the interface S1, and control information is communicated between the Home-eNB and the MME. A plurality of Home-eNBs are connected to one MME.

  Next, FIG. 7B will be described. A mobile terminal (UE) 71 performs transmission / reception with the base station 72. The base station 72 is classified into an eNB (non-CSG cell) 72-1 and a Home-eNB (CSG cell) 72-2. As in FIG. 7A, the eNB 72-1 is connected to the MME 73 via the interface S1, and control information is communicated between the eNB and the MME. A plurality of MMEs are connected to one eNB. On the other hand, Home-eNB 72-2 is connected to MME 73 via HeNBGW (Home-eNB GateWay) 74. Home-eNB and HeGW are connected by interface S1, and HeNBGW74 and MME73 are connected via interface S1_flex. One or a plurality of Home-eNBs 72-2 are connected to one HeNBGW 74, and information is communicated through S1. The HeNBGW 74 is connected to one or a plurality of MMEs 73, and information is communicated through S1_flex.

  By connecting one HeNBGW 74 to a Home-eNB belonging to the same CSG-ID using the configuration of FIG. 7B, a plurality of information belonging to the same CSG-ID, such as registration information, can be obtained from the MME 73. When transmitting to the Home-eNB 72-2, it is once transmitted to the HeNBGW 74, and then transmitted to the plurality of Home-eNBs 7-2. Can be enhanced. On the other hand, when each Home-eNB 72-2 communicates individual information with the MME 73, the Home-eNB 72-2 is only passed (transmitted) through the HeNBGW 74 without processing the information there. And MME 73 can communicate with each other as if they were directly connected.

  FIG. 8 is a block diagram showing a configuration of a mobile terminal (terminal 71 in FIG. 7) according to the present invention. Transmission processing of the mobile terminal shown in FIG. 8 will be described. First, control data from the protocol processing unit 801 and user data from the application unit 802 are stored in the transmission data buffer unit 803. The data stored in the transmission data buffer unit 803 is transferred to the encoder unit 804 and subjected to encoding processing such as error correction. There may exist data that is directly output from the transmission data buffer unit 803 to the modulation unit 805 without being encoded. The data encoded by the encoder unit 804 is subjected to modulation processing by the modulation unit 805. The modulated data is converted into a baseband signal, and then output to the frequency conversion unit 806 where it is converted into a radio transmission frequency. Thereafter, a transmission signal is transmitted from the antenna 807 to the base station 312. In addition, the reception process of the mobile terminal 311 is executed as follows. A radio signal from the base station 312 is received by the antenna 807. The reception signal is converted from a radio reception frequency to a baseband signal by the frequency conversion unit 806, and demodulated by the demodulation unit 808. The demodulated data is transferred to the decoder unit 809 and subjected to decoding processing such as error correction. Of the decoded data, control data is passed to the protocol processing unit 801, and user data is passed to the application unit 802. A series of processing of the mobile terminal is controlled by the control unit 810. Therefore, the control unit 810 is connected to each unit (801 to 809), which is omitted in the drawing.

  FIG. 9 is a block diagram showing the configuration of the base station (base station 72 of FIG. 7) according to the present invention. A transmission process of the base station shown in FIG. 9 will be described. The EPC communication unit 901 transmits and receives data between the base station 72 and EPC (MME73, HeNBGW74, etc.). The other base station communication unit 902 transmits / receives data to / from other base stations. The EPC communication unit 901 and the other base station communication unit 902 exchange information with the protocol processing unit 903, respectively. Control data from the protocol processing unit 903 and user data and control data from the EPC communication unit 901 and the other base station communication unit 902 are stored in the transmission data buffer unit 904. Data stored in the transmission data buffer unit 904 is transferred to the encoder unit 905 and subjected to encoding processing such as error correction. There may exist data that is directly output from the transmission data buffer unit 904 to the modulation unit 906 without being encoded. The encoded data is subjected to modulation processing by the modulation unit 906. The modulated data is converted into a baseband signal, and then output to the frequency conversion unit 907 to be converted into a radio transmission frequency. Thereafter, a transmission signal is transmitted from the antenna 908 to one or a plurality of mobile terminals 71. Further, the reception process of the base station 72 is executed as follows. Radio signals from one or a plurality of mobile terminals 311 are received by the antenna 908. The received signal is converted from a radio reception frequency to a baseband signal by the frequency conversion unit 907, and demodulated by the demodulation unit 909. The demodulated data is transferred to the decoder unit 910, and decoding processing such as error correction is performed. Of the decoded data, the control data is passed to the protocol processing unit 903 or the EPC communication unit 901 and the other base station communication unit 902, and the user data is passed to the EPC communication unit 901 and the other base station communication unit 902. A series of processing of the base station 72 is controlled by the control unit 911. Therefore, although the control part 911 is abbreviate | omitted in drawing, it is connected with each part (901-910).

  FIG. 10 is a block diagram showing a configuration of an MME (Mobility Management Entity) according to the present invention. The PDN GW communication unit 1001 transmits and receives data between the MME 73 and the PDN GW. The base station communication unit 1002 transmits and receives data between the MME 73 and the base station 72 using the S1 interface. When the data received from the PDN GW is user data, the user data is passed from the PDN GW communication unit 1001 to the base station communication unit 1002 via the user plane processing unit 1003 and transmitted to one or a plurality of base stations 72. The When the data received from the base station 72 is user data, the user data is transferred from the base station communication unit 1002 to the PDN GW communication unit 1001 via the user plane processing unit 1003 and transmitted to the PDN GW.

  When the data received from the PDN GW is control data, the control data is transferred from the PDN GW communication unit 1001 to the control plane control unit 1005. When the data received from the base station 72 is control data, the control data is transferred from the base station communication unit 1002 to the control plane control unit 1005. The HeNBGW communication unit 1004 is provided when the HeNBGW 74 exists, and performs data transmission / reception through an interface (IF) between the MME 73 and the HeNBGW 74 depending on the information type. The control data received from the HeNBGW communication unit 1004 is passed from the HeNBGW communication unit 1004 to the control plane control unit 1005. The result of the process in the control plane control unit 1005 is transmitted to the PDN GW via the PDN GW communication unit 1001. Further, the result processed by the control plane control unit 1005 is transmitted to one or a plurality of base stations 72 via the S1 interface via the base station communication unit 1002, and to one or a plurality of HeNBGWs 74 via the HeNBGW communication unit 1004. Sent.

  The control plane control unit 1005 includes a NAS security unit 1005-1, an SAE bearer control unit 1005-2, an idle state mobility management unit 1005-3, and the like, and performs overall processing for the control plane. The NAS security unit 1005-1 performs security of a NAS (Non-Access Stratum) message. The SAE bearer control unit 1005-2 manages the SAE (System Architecture Evolution) bearer. The idle state mobility management unit 1005-3 performs mobility management in a standby state (LTE-IDLE state, also simply referred to as idle), generation and control of a paging signal in the standby state, and one or more mobile terminals 71 being served thereby Add, delete, update, search, tracking area list (TA List) management, etc. The MME initiates the paging protocol by transmitting a paging message to a cell belonging to a tracking area (tracking area: TA) in which the UE is registered. The idle state mobility management unit 1005-3 may perform CSG management, CSG-ID management, and white list management of the Home-eNB 72-2 connected to the MME. In the management of CSG-ID, the relationship between the mobile terminal corresponding to the CSG-ID and the CSG cell is managed (added, deleted, updated, searched). For example, it may be a relationship between one or a plurality of mobile terminals registered for user access with a certain CSG-ID and a CSG cell belonging to the CSG-ID. In white list management, the relationship between a mobile terminal and a CSG-ID is managed (added, deleted, updated, searched). For example, the white list may store one or a plurality of CSG-IDs registered by a certain mobile terminal as a user. Although these CSG-related management may be performed in other parts of the MME 73, tracking by the idle state mobility management unit 1005-3 instead of the CSG-ID currently being discussed at the 3GPP meeting A method using an area code (Tracking Area Code) can be performed efficiently. A series of processing of the MME 313 is controlled by the control unit 1006. Therefore, although the control part 1006 is abbreviate | omitted in drawing, it is connected with each part (1001-1005).

  FIG. 11 is a block diagram showing the configuration of the HeNBGW according to the present invention. The EPC communication unit 1101 transmits and receives data between the HeNBGW 74 and the MME 73 using the S1_flex interface. The base station communication unit 1102 transmits and receives data between the HeNBGW 74 and the Home-eNB 72-2 using the S1 interface. The location processing unit 1103 performs a process of transmitting registration information and the like to a plurality of Home-eNBs among data from the MME 73 passed via the EPC communication unit 1101. The data processed by the location processing unit 1103 is transferred to the base station communication unit 1102 and transmitted to one or more Home-eNBs 72-2 via the S1 interface. Data that does not require processing in the location processing unit 1103 and is simply passed (transmitted) is passed from the EPC communication unit 1101 to the base station communication unit 1102 and is sent to one or a plurality of Home-eNBs 72-2 via the S1 interface. Sent. A series of processing of the HeNBGW 74 is controlled by the control unit 1104. Therefore, the control unit 1104 is connected to each unit (1101 to 1103), which is omitted in the drawing.

  Next, an example of a general cell search method in a mobile communication system will be shown. FIG. 12 is a flowchart illustrating an outline from a cell search to a standby operation performed by a mobile terminal (UE) in an LTE communication system. When cell search is started in the mobile terminal, slot timing and frame timing using the first synchronization signal (P-SS) and second synchronization signal (S-SS) transmitted from the neighboring base stations in step ST1201. Synchronize. In combination with P-SS and S-SS, the synchronization signal (SS) is assigned a synchronization code corresponding to a PCI (Physical Cell Identity) assigned to each cell. Currently, 504 PCIs are being studied, and the 504 PCIs are used for synchronization, and the PCI of the synchronized cell is detected (specified). Next, for a synchronized cell, in step ST1202, a reference signal RS (Reference Signal) transmitted from the base station for each cell is detected, and the received power is measured. The reference signal RS uses a code corresponding to PCI one-to-one, and can be separated from other cells by correlating with the code. By deriving the RS code of the cell from the PCI specified in ST1201, it becomes possible to detect the RS and measure the RS received power. Next, in ST1203, the cell having the best RS reception quality (for example, the cell having the highest RS reception power) is selected from one or more cells detected up to ST1202. Next, in ST 1204, PBCH of the best cell is received, and BCCH which is broadcast information is obtained. A MIB (Master Information Block) including cell configuration information is carried on the BCCH on the PBCH. MIB information includes, for example, DL (downlink) system bandwidth, the number of transmission antennas, SFN (System Frame Number), and the like.

  Next, at 1205, the DL-SCH of the cell is received based on the MIB cell configuration information, and SIB (System Information Block) 1 in the broadcast information BCCH is obtained. SIB1 includes information about access to the cell, information about cell selection, and scheduling information of other SIBs (SIBk; integer of k ≧ 2). SIB1 includes a TAC (Tracking Area Code). Further, the CIB-ID may be included in the SIB1. Next, in ST1206, the mobile terminal compares the TAC received in ST1205 with the TAC already held by the mobile terminal. If the result of the comparison is the same, a standby operation is started in the cell. If they are different from each other, the mobile terminal requests a change of TA in order to perform TAU (Tracking Area Update) to the core network (Core Network, EPC) (including MME) through the cell. The core network updates the TA based on the identification number (UE-ID or the like) of the mobile terminal sent from the mobile terminal together with the TAU request signal. After updating the TA, the core network transmits a TAU acceptance signal to the mobile terminal. The mobile terminal rewrites (updates) the TAC (or TAC list) held by the mobile terminal with the TAC of the cell. Thereafter, the mobile terminal enters a standby operation in the cell.

  In LTE and UMTS (Universal Mobile Telecommunication System), introduction of a CSG (Closed Subscriber Group) cell is being studied. As described above, access is permitted only to one or a plurality of mobile terminals registered in the CSG cell. One or a plurality of mobile terminals registered with the CSG cell constitute one CSG. A unique identification number called CSG-ID is assigned to the CSG configured as described above. A single CSG may have a plurality of CSG cells. If a mobile terminal registers in one of the CSG cells, it can access other CSG cells to which the CSG cell belongs. In addition, Home-eNB in LTE and Home-NB in UMTS may be used as a CSG cell. One or more CSG cells included in one CSG-ID belong to the same TA. For this reason, one or a plurality of CSG cells included in one CSG-ID broadcast the same TAC on broadcast information to a mobile terminal being served thereby. The mobile terminal registered in the CSG cell has a white list. Specifically, the white list is stored in the SIM / USIM. The white list carries CSG information of the CSG cell registered by the mobile terminal. Specifically, CSG-ID, TAI (Tracking Area Identity), TAC, etc. can be considered as CSG information. If CSG-ID and TAC are associated with each other, either one is sufficient. Further, GCI may be used as long as CSG-ID or TAC is associated with GCI (Global Cell Identity). From the above, a mobile terminal that does not have a white list (including the case where the white list is empty in the present invention) cannot access a CSG cell, and only accesses a non-CSG cell. Can not. On the other hand, a mobile terminal having a white list can access both a registered CSG-ID CSG cell and a non-CSG cell.

  A problem arises when a mobile terminal performs a cell search in a location where many CSG cells exist. FIG. 13 shows a cell conceptual diagram when there are many CSG cells. In the figure, 1301 indicates a non-CSG cell by eNB, and 1302 indicates a CSG cell by Home-eNB. 1303 is a mobile terminal. Many CSG cells are required to be installed in condominiums, schools, and companies. The CSG cell is installed in each room in the apartment, in each classroom in the school, and in each section in the company, and a usage method is required so that only the user registered in each CSG cell can use the CSG cell. . Furthermore, the CSG cell is assumed to have a portable size and weight, and installation and removal of these CSG cells are required to be performed frequently and flexibly. Considering such a request, radio waves from many CSG cells are simultaneously transmitted at a certain point. That is, in a condominium, a school, a company, etc., a situation occurs in which the mobile terminal 1303 is in a position where radio waves from many CSG cells can reach, as shown in FIG. In such a situation, there are mobile terminals having a white list and mobile terminals not having a white list. In this situation, consider a case where the mobile terminal performs a cell search.

  FIG. 14 shows an example of a cell search flowchart of a mobile terminal in a position where radio waves from a number of CSG cells reach. When the mobile terminal starts a cell search, the operation described as a general case in FIG. 12 is performed. In ST1401, the first synchronization signal P-SS and the second synchronization signal S-SS are synchronized, and PCI (Physical Cell Identity) is detected (specified). In ST1402, the RS is detected and the received power of RS is measured. In ST1403, the best cell is selected, and PBCH reception and MIB information of the cell selected in ST1404 are obtained. In ST1405, DL-SCH is received and information of SIB1 is obtained. Then, if the TAC information of SIB1 is the same as the TAC possessed by the mobile terminal, it shifts to a standby operation. However, if they are not the same, the operation differs from that shown in the general case. As described above, in such a situation, there are mobile terminals having a white list and mobile terminals having no white list. In ST1407, it is determined whether the mobile terminal has a white list. If the mobile terminal has a white list, it is determined in ST 1408 whether the TAC of SIB1 is the same as the CSG-ID (TAC) in the white list. This is because if the CSG-ID (TAC) is not the same, access to the cell is prohibited due to unregistration. If they are the same, they have already been registered, so access to the cell is permitted, and a transition is made to a standby operation. If they are different, the cell cannot be accessed because it is not registered, and the mobile terminal makes a transition to ST1409. In ST1409, the mobile terminal determines whether the cell is a CSG cell. In LTE, a CSG indicator indicating whether the own cell is a CSG cell is included in SIB1 of broadcast information of each cell. Therefore, the determination in ST1409 can be performed using the CSG indicator included in the information of SIB1 obtained in ST1405. When the CSG indicator has shown that it is a CSG cell, it transfers to ST1410. In ST1410, the mobile terminal stores the PCI of the cell and sets so as to exclude the PCI of the cell at the time of subsequent cell search and selection of the best cell. This is because even if the cell is a CSG cell, it is a CSG-ID (TAC) cell that is not on the white list of the mobile terminal. In order to store the PCI of the inaccessible CSG cell once the mobile terminal has performed cell search or best cell selection, an inaccessible PCI list or the like may be provided and written to the list. The PCI of an inaccessible CSG cell may be reset or erased when a timer is provided and the timer period ends and / or when a new CSG-ID is registered. If it is determined in ST1409 that the cell is not a CSG cell, it shifts to a standby operation after TAU because it is a non-CSG cell.

  On the other hand, if the mobile terminal does not have a white list in ST1407, the mobile terminal makes a transition to ST1409. If it is determined in ST1409 that the cell is not a CSG cell, the process proceeds to a standby operation after TAU. However, if it is a CSG cell, the process of ST1410 is performed in the same manner, and cell search and best cell selection operations are performed again. Do. When cell search and best cell selection are performed again and a CSG cell is found, ST1407, ST1409, and ST1410 are performed again, and cell search and best cell selection are performed again. As shown in FIG. 13, a mobile terminal that does not have a white list in this manner performs cell search and best cell selection for all cells even if it is known that a CSG cell cannot be accessed absolutely. In the case of a mobile terminal in a position where radio waves from many Home-eNBs reach, there is a high possibility that many CSG cells are searched and the best cell is selected. ST1401, ST1402, ST1403, ST1404, ST1405, ST1406, The operations of ST1407, ST1409, and ST1410 are repeated many times, and it takes a long time to enter the standby operation, resulting in a problem that a large control delay occurs as a system. In addition, there is a problem that power consumption becomes enormous in a mobile terminal that has to repeat cell search. This problem may occur even if the processing of storing the PCI of the CSG cell that cannot be accessed by the mobile terminal in ST1410 and excluding the PCI of the cell at the time of subsequent cell search and selection of the best cell is performed. . This problem becomes a serious problem when the future arrangement situation of CSG cells as described above is assumed.

  In order to solve such a problem, 3GPP discusses dividing all PCI (Physical Cell Identity) into a CSG cell and a non-CSG cell (referred to as a PCI split) (non-patent document). 4). By dividing all PCIs for CSG cells and non-CSG cells, a mobile terminal that does not have a white list at the time of cell search can perform P-SCH and S-SCH synchronization using PCI for non-CSG cells. Since it is sufficient to specify the PCI, the CSG cell is not searched. However, the mobile terminal must always recognize the PCI split information before performing a cell search. For this reason, 3GPP proposes that the PCI split range is fixed, that is, the PCI range assigned to the CSG cell and the PCI range assigned to the non-CSG cell are determined in advance. For example, PCI # 0 to PCI # 49 are allocated to CSG cells, and PCI # 50 to PCI # 503 are allocated to non-CSG cells in advance and described in the standard. In this way, the mobile terminal can always recognize this value before performing a cell search, and a mobile terminal that does not have a white list does not needlessly search for a CSG cell during the cell search. It becomes possible.

  However, as described above, the method of predetermining the PCI range to be assigned to the CSG cell and the PCI range to be assigned to the non-CSG cell is not satisfactory for the above-described request to the Home-eNB. That is, Home-eNB assumes portable size and weight, and installation and removal of these Home-eNBs are required to be performed frequently and flexibly. Considering this requirement, the number of CSG cells will vary depending on various situations such as operator, frequency layer, installation location, and time. Therefore, determining PCI split information in advance causes a problem that it is not possible to cope with the number of CSG cells that change due to flexible and frequent installation and removal of Home-eNBs.

  In order to solve this problem, a method is disclosed in which PCI split information is broadcast to mobile terminals being served by broadcast information that is received in the minimum necessary for an operation waiting from a cell search. FIG. 15 is a sequence diagram for reporting PCI split information in an LTE communication system. For example, in an LTE communication system, there is SIB1 as broadcast information received as a minimum necessary for an operation waiting from a cell search. All base stations (Home-eNB (CSG cell) and eNB (non-CSG cell)) put PCI split information in SIB1, and map BCCH including SIB1 to DL-SCH. All base stations each transmit DL-SCH to the mobile terminals (UEs) being served thereby to notify the PCI split information included in SIB1. Here, the PCI split information transmitted from all base stations is the PCI split information of the frequency layer to which the own cell belongs. Next, FIG. 16 shows a flowchart of cell search of a mobile terminal in this method. The mobile terminal starts cell search. First, in ST1601, it is determined whether the mobile terminal has PCI split information. For example, when the power is turned on, if the PCI split information is not yet held, the process proceeds to ST1602. The mobile terminal that has moved to ST1602 performs the method described in the flowchart shown in FIG. 14 and performs the processes of ST1602 to ST1611. Here, the point different from the flowchart shown in FIG. 14 is that a process of receiving PCI split information contained in SIB1 sent via DL-SCH in ST1606 is performed. The mobile terminal that has received the PCI split information stores the PCI split information. A PCI split information list may be provided and stored in the list together with the PLMN and the frequency layer. The PCI split information stored in the list is rewritten when the broadcast information is corrected.

  The PCI split information stored in the list may be reset or deleted when reselection is performed between frequency layers when power is turned off / on, or when reselection between other systems is performed. If the mobile terminal that has obtained PCI split information in ST1606 proceeds to ST1611, it can use the PCI split information in ST1601 when the next cell search or best cell is selected. The mobile terminal determines in ST1601 that it has PCI split information, and moves to ST1612. It is determined whether the mobile terminal that has moved to ST1612 has a white list. If it has a white list, the process moves to ST1602, and the operations of ST1602 to ST1611 are performed again. However, the mobile terminal that does not have the whitelist moves to ST1613 and performs P-SS and S-SS synchronization using the PCI of the non-CSG cell based on the PCI split information obtained in ST1606 of the first cell search. PCI is detected (identified). The mobile terminal that has identified the PCI moves to ST1614 and performs the processes of ST1614 to ST1618. This process is the same as that in general cell search. What is important here is that the CSG cell is not searched because PCI is detected (identified) by performing P-SS and S-SS synchronization using the PCI of the non-CSG cell. For this reason, even if it is known that a mobile terminal that does not have a white list that is generated by the method described in the flowchart shown in FIG. 14 cannot access the CSG cell, the operations of ST1602 to ST1611 (except for ST1609) are repeated. The problem of repeating is solved.

  Furthermore, for example, when a mobile terminal that does not have a white list that has obtained PCI split information during the first cell search after power-on performs cell search again, the mobile terminal has PCI split information. The answer is “yes” and the process proceeds to ST1612. The mobile terminal that has moved to ST1612 performs the processing of ST1613 to ST1618. Therefore, even in this case, even if it is known that a mobile terminal that does not have a white list that is generated by the method described with reference to the flowchart shown in FIG. 14 cannot access the CSG cell, operations of ST1602 to ST1611 (except ST1609) are performed. The problem of repeating the process over and over again is solved.

  There are various types of broadcast information blocks. When PCI split information is put in another SIB of SIB1, it is not received in an operation waiting for a general cell search. In order to receive other broadcast information blocks (SIBk; integers of k ≧ 2) of MIB and SIB1, since it is necessary to receive scheduling information (assignment information) of other SIBs on SIB1, further time is required. A delay occurs, and the power consumption of the mobile terminal further increases. By inserting the PCI split information into the broadcast information received at the minimum necessary for the operation waiting from the cell search, the mobile terminal can obtain the PCI split information with low power consumption in a short time without having to obtain another broadcast information block. Is possible. As a system, it is possible to construct a good system with little control delay. For example, in an LTE communication system, MIB or SIB1 is broadcast information received as a minimum necessary for an operation waiting from a cell search.

  By using the method disclosed in the present embodiment for reporting PCI split information on SIB1 of broadcast information to a mobile terminal being served thereby, a mobile terminal that does not have a white list performs a second or subsequent cell search. It is possible to eliminate unnecessary searching for CSG cells. For this reason, it takes a lot of time from the cell search to the start of the standby operation, so that the problem that a large control delay occurs as a system and the problem that the power consumption becomes enormous in the mobile terminal can be solved. Therefore, it will be possible to meet the demand for installation of a large number of Home-eNBs in the future and the demand for flexible changes in the number of CSG cells caused by frequent and flexible installation and removal of Home-eNBs. A mobile communication system can be constructed.

  All cells (non-CSG cells and CSG cells) disclosed in the present embodiment broadcast the PCI split information to the mobile terminals being served by the broadcast information that is received at the minimum necessary for the operation waiting from the cell search. By using the method, even a mobile terminal having a white list can selectively search for a CSG cell or a non-CSG cell. For example, when a mobile terminal having a white list preferentially accesses a CSG cell instead of a non-CSG cell, the CSG cell is preferentially used by using PCI split information obtained by receiving SIB1. Can be cell-searched. In this case, the operation after ST1612 shown in FIG. 16 may be performed as follows. If it is determined in ST1612 that the mobile terminal has a white list, the first synchronization signal P-SS and the second synchronization signal S-SS are synchronized using the PCI of the CSG cell to detect (specify) the PCI. . A reference signal (RS) is detected using the specified PCI, and the received power is measured. Then, the best cell is selected by comparing the measured received power. The PBCH of the selected cell is received to receive the MIB, and further the DL-SCH is received to receive SIB1. If the tracking area code (Tracking Area Code TAC) on the SIB1 is the same as that held by the mobile terminal, the operation proceeds to the standby operation. If the tracking area code TAC is different, the tracking area code TAC of the SIB1 is in the white list held by the mobile terminal. It is compared whether it is the same as CSG-ID (TAC). If they are the same, the operation shifts to the standby operation. If they are different, the cell search is performed again. Then, the cell search is performed using the PCI of the CSG cell, and when there is no cell to be selected, the operation of performing the cell search using the PCI of the non-CSG cell is started. This makes it possible to search for CSG cells with priority, and to perform cell search and cell selection for non-CSG cells when there are no selectable CSG cells. Become.

  In the above description, a case where a mobile terminal having a white list preferentially accesses a CSG cell instead of a non-CSG cell has been described, but conversely, an access to a non-CSG cell instead of a CSG cell. It is also possible to preferentially perform. If it is determined in ST1612 that the mobile terminal has a white list, P-SS and S-SS synchronization is performed using the PCI of the non-CSG cell to detect (specify) the PCI. RS is detected using the specified PCI, and RS received power is measured. The best cell is selected by comparing the measured RS received power. The PBCH of the selected cell is received to receive the MIB, and further the DL-SCH is received to receive SIB1. If the TAC on the SIB1 is the same as the TAC possessed by the mobile terminal, the operation shifts to a standby operation. If the TAC is different, the operation shifts to a post-TAU standby operation. Then, the cell search is performed using the PCI of the non-CSG cell, and when the cell to be selected does not exist, the operation of performing the cell search using the PCI of the CSG cell is started. In this way, it is possible to search for a non-CSG cell preferentially, and when there are no selectable non-CSG cells, cell search and cell selection for the CSG cell can be performed. It becomes possible.

  Therefore, even in a mobile terminal having a white list, it is possible to eliminate searching for a useless cell when performing a second or subsequent cell search, and it takes a long time to start a standby operation after the cell search. Therefore, it is possible not only to solve the problem that a large control delay occurs in the system and the problem that the power consumption becomes enormous in the mobile terminal, but also to selectively search for CSG cells or non-CSG cells. It becomes. As a result, a request for installing a large number of future Home-eNBs, a request for responding to a flexible change in the number of CSG cells caused by frequent and flexible installation and removal of Home-eNBs, For example, it is possible to construct a mobile communication system that can respond to a request of a mobile terminal that wants to access a registered CSG cell with priority over a non-CSG cell or a system that the user wants to access.

  In the above-described method, the method of notifying PCI split information on SIB1 of broadcast information to an affiliated mobile terminal is disclosed. However, the method of notifying PCI split information to an affiliated mobile terminal of MIB on the broadcast information is disclosed. It is also good. FIG. 15 is applicable as a sequence diagram in this method. All base stations (eNB and Home-eNB) put PCI split information in MIB and map BCCH including MIB to PBCH. Then, all base stations transmit PBCH to the mobile terminals (UEs) being served thereby to notify the PCI split information included in the MIB. Here, the PCI split information transmitted from all base stations is the PCI split information of the frequency layer to which the own cell belongs. In the mobile terminal cell search flowchart in this method, ST1605 and ST1606 in FIG. 16 may be changed as follows. Since the PCI split information is reported from the base station in the MIB, the mobile terminal performs PCI split information reception processing in ST1605. On the other hand, in ST1606, PCI split information is not received. This change can be realized. The effect described above can be obtained in the same manner by using a method of notifying PCI split information on MIB of notification information to a mobile terminal being served thereby.

  A modification of the first embodiment will be described. Embodiment 1 discloses a method of broadcasting PCI split information from all cells (CSG cells and non-CSG cells) to the mobile terminal being served by broadcast information received in the minimum necessary for the operation waiting from the cell search. In the first modification, a method is disclosed in which PCI split information is transmitted only from the CSG cell to the mobile terminal being served by the broadcast information that is received in the minimum necessary for the operation waiting from the cell search. The sequence diagram which alert | reports the PCI split information in a LTE communication system is shown.Home-eNB puts PCI split information in SIB1, maps BCCH containing SIB1 to DL-SCH, and all Home-eNB base stations are subordinate. PCI split information transmitted to the mobile terminal (UE) by transmitting DL-SCH and entering SIB1 Here, the PCI split information transmitted by the Home-eNB is the PCI split information of the frequency layer to which the own cell belongs, whereas the eNB broadcasts the PCI split information to the user equipment (UE) being served thereby. In the case of this modification, the mobile terminal can obtain PCI split information only when the cell selected by the cell search or the best cell is a CSG cell, but even in this case, the mobile terminal does not have a white list. Once the CSG cell is selected as the best cell, the terminal repeatedly performs the operations of ST1602 to ST1611 (excluding ST1609) in FIG. 16 such as cell search for a CSG cell that cannot be accessed thereafter and best cell selection. It becomes possible to solve the problem of repetition.

  Only the effect described in the first embodiment can be obtained by using the method of reporting PCI split information to the mobile terminal being served by SIB1 or MIB of broadcast information only from the Home-eNB disclosed in the first modification. In addition, new information (PCI split information) for CSG need not be transmitted to the broadcast information from the non-CSG cell. This eliminates the need for a change in an LTE system (eUTRA / eUTRAN) that does not include an existing CSG, and improves compatibility.

Embodiment 2. FIG.
In the first embodiment, all cells (non-CSG cells and CSG cells) put PCI (Physical Cell Identity) split information on the broadcast information received from cell search to the minimum necessary for standby operation to the mobile terminals being served thereby A method for informing was disclosed. The PCI split information is the PCI split information of the frequency layer to which the own cell belongs. In Embodiment 2, a method is disclosed in which all base stations (eNB and Home-eNB) broadcast PCI split information of other frequency layers to mobile terminals being served as broadcast information. FIG. 18 is a sequence diagram for reporting PCI split information of another frequency layer in the LTE communication system. All base stations (Home-eNB and eNB) include PCI split information of other frequency layers different from the frequency layer to which the own cell belongs in the broadcast information (BCCH). Then, all base stations notify the broadcast information to mobile terminals (UEs) being served thereby. Accordingly, the mobile terminal being served thereby can obtain PCI split information of another frequency layer using broadcast information from the serving cell. For this reason, when a mobile terminal needs processing related to another frequency layer such as cell search, cell selection, cell reselection, or handover, the mobile terminal may use PCI split information of the other frequency layer. It becomes possible. Since PCI split information of other frequency layers can be used, for example, when performing cell search and cell selection between frequency layers, PCI split information of a desired frequency layer is used from the first cell search and cell selection of the operation. It becomes possible. A mobile terminal that does not have a white list can be prevented from searching for CSG cells that cannot be accessed when performing a cell search. For this reason, it takes a lot of time from cell search to another frequency layer to start standby operation, and there is a problem that a large control delay occurs as a system, and power consumption in the mobile terminal becomes enormous. The problem can be solved. Therefore, it will be possible to meet the demand for installation of a large number of home-eNBs in the future and the demand for flexible changes in the number of CSG cells caused by frequent and flexible installation and removal of home-eNBs. A mobile communication system can be constructed. There may be one or more other frequency layers. In that case, the mobile terminal may store the PCI split information, the priority order of the frequency, and the like in pairs (for example, may be stored as a list).

  In the second embodiment, PCI split information of another frequency layer different from the frequency layer to which the own cell belongs is included in the broadcast information (BCCH). Specifically, you may add to SIB5 which is the alerting | reporting information block in which the alerting | reporting information of the frequency layer different from a self-cell currently under discussion in 3GPP is carried. The base station maps BCCH including SIB5 carrying broadcast information of a frequency layer different from that of the own cell to DL-SCH, and transmits DL-SCH to the user equipment (UE) being served thereby. By receiving the SIB5, the mobile terminal uses the PCI split information of the other frequency layer in the SIB5 in the case of cell search to the other frequency layer, cell selection, etc. Cell search to other frequency layers, cell selection, and the like can be performed.

  Further, PCI split information of another frequency layer different from the frequency layer to which the own cell belongs may be transmitted as individual information. For example, the cell may include PCI split information of another frequency layer different from the frequency layer to which the own cell belongs in the individual control information (DCCH) and transmit the information to individual mobile terminals being served thereby. In addition, a mobile terminal being served by a certain cell may transmit a request message for individually requesting the cell to transmit the PCI split information as individual information. Further, for example, a cell may include PCI split information of another frequency layer different from the frequency layer to which the own cell belongs in paging information (PCCH) and transmit the information to each mobile terminal being served thereby. By doing so, each cell can transmit PCI split information of another frequency layer different from the frequency layer to which the own cell belongs as necessary, so that the use efficiency of radio resources can be improved. it can.

  In the first and second embodiments, PCI split information is transmitted from the non-CSG cell or the CSG cell to the mobile terminal. The PCI split information may be generated in the core network and transmitted to the mobile terminal via a non-CSG cell or a CSG cell. Even in this case, the same effect as described above can be obtained.

  In the first and second embodiments, the LTE (Long Term Evolution) communication system and UMTS (Universal Mobile Telecommunication System) using Home-eNB and Home-NB using CSG (Closed Subscriber Group Cell) have been described. The present invention is also applicable to UMTS using Home-NB that does not use CSG. PCI may be divided into Home-NB and other NBs, and PCI split information may be included in broadcast information from all base stations (NB and Home-NB) as PCI split information and broadcasted to a mobile terminal being served thereby. Of the broadcast information, the PCI split information may be included in the broadcast information block necessary for cell search and cell selection and broadcast to the mobile terminals being served thereby. As a result, mobile terminals that are not registered in the Home-NB do not perform useless cell search and cell selection, and it takes a long time to start standby operation after cell search, resulting in a large control delay as a system. Can be solved, and the problem that power consumption becomes enormous in a mobile terminal can be solved. Therefore, it is possible to construct a mobile communication system that can respond to the demands when the number of Home-NB installations becomes large in the future or when the installation and removal of Home-NBs is frequent and flexible. Become.

Embodiment 3 FIG.
Responding to requests for the installation of a large number of CSG (Closed Subscriber Group) cells in the future and to respond to flexible changes in the number of CSG cells caused by frequent and flexible installation and removal of CSG cells In order to construct a mobile communication system, the first and second embodiments have disclosed a method of transmitting and receiving PCI split information. In the present embodiment, problems in the operation of the white list caused by frequent and flexible installation and removal of a large number of CSG cells and CSG cells are shown, and the problems are solved. A method is disclosed.

  Currently, 3GPP discusses how to obtain a whitelist when a mobile terminal registers in a CSG cell in the LTE system (Non-Patent Document 5). In 3GPP, a method in which a mobile terminal is notified of a white list via a non-CSG cell is agreed. FIG. 19 shows a case where a Home-eNB (CSG cell) exists in the area of an eNB (non-CSG cell). The mobile terminal (UE) is in the area of the CSG cell. In the figure, there is one CSG cell in a non-CSG cell, but a plurality of CSG cells may exist. A method for obtaining a whitelist in such a situation will be described. First, the owner of the Home-eNB notifies the network operator that the user terminal (UE) owned by the user has been registered for user access. Thereafter, the network operator notifies the white list from the upper layer to the mobile terminal (UE). The notification of the white list is performed via the eNB (non-CSG cell).

  FIG. 20 shows a sequence diagram of a method for notifying a white list through a non-CSG cell, which is discussed in 3GPP. The figure shows a case of an LTE communication system, in which “Owner” is the owner of the Home-eNB, and “CN” is a core network (MME, base station controller). The core network includes MME and the like. When the user registers the user access to the home-eNB, in ST2001, the owner of the home-eNB notifies the network operator that the user-owned user equipment (UE) is registered for user access to the home-eNB. Therefore, for example, the mobile terminal identification number (UE-ID, IMSI and other mobile terminal identification information) is transmitted to the core network. In ST2002, the network operator that has received the mobile terminal identification number (UE-ID, IMSI, etc.) transmitted from the owner allows the mobile terminal to access the Home-eNB from the core network. -Send an access permission setting request to the eNB. In ST2003, the Home-eNB that has received the access permission setting request performs setting to permit access from the mobile terminal. Next, in ST2004, the network operator transmits a whitelist from the core network to the eNB of the non-CSG cell in which the Home-eNB exists. The eNB that has received the white list in ST 2005 notifies the mobile terminal of the white list. The mobile terminal notified of the white list in ST2006 stores the white list in its own mobile terminal. Specifically, it is proposed to be stored in a SIM / USIM (which may be a storage device such as a memory or a CPU).

  A mobile terminal that does not have a white list cannot access a CSG cell and can access only a non-CSG cell. On the other hand, a mobile terminal having a white list can access both a registered CSG-ID CSG cell and a non-CSG cell.

  The method for obtaining the whitelist when the mobile terminal registers in the CSG cell, which has been discussed in 3GPP, has been described above. However, in this method, the mobile terminal receives the white list via the eNB (non-CSG cell). This is a necessary condition that the mobile terminal is served by a non-CSG cell. That is, there is a problem that it is impossible to obtain the white list when the mobile terminal is not under the control of the non-CSG cell.

  FIG. 21 illustrates a case where the Home-eNB (CSG cell) registered by the mobile terminal is outside the area of the non-CSG cell. Since the mobile terminal is not under the control of the non-CSG cell, it cannot communicate with the non-CSG cell. For this reason, even if the mobile terminal registers in the CSG cell, the white list cannot be obtained. Since a mobile terminal that does not have a white list is not allowed to access the CSG cell, it cannot access the registered CSG cell. Therefore, even though a mobile terminal that does not have a white list is under the control of a CSG cell that has been registered for user access, the mobile terminal cannot perform cell search or cell selection for the CSG cell. In order to solve this problem, 3GPP proposes that a mobile terminal outside the area of a non-CSG cell that has performed user access registration in a CSG cell starts manual search (Non-Patent Document 5). In Non-Patent Document 5, a mobile terminal outside the area of the non-CSG cell that has performed user access registration with the CSG cell does not yet have a whitelist and is within the area of the CSG cell that has been registered for user access. In this case, it is described that a TAU is transmitted to the core network through the CSG cell in which user access registration is performed in order to obtain a white list by starting a manual search.

  However, the 3GPP proposal does not show a specific method for this manual search. There is no description of how to enable TAU to be sent to the core network via the CSG cell. Here, by disclosing a specific method thereof, when a user equipment that does not have a white list performs user access registration with the CSG cell, the white list can be obtained from the CSG cell. FIG. 22 discloses a specific sequence diagram when a mobile terminal that does not have a white list in a LTE communication system, for example, starts manual search. When the user registers the user terminal in the CSG cell (here, Home-eNB), the owner of the CSG cell registers the user terminal of the user terminal (UE) owned by the user in the CSG cell. For example, the mobile terminal identification number (UE-ID, IMSI, etc.) is transmitted to the core network. In ST2202, the network operator that has received the mobile terminal identification number (UE-ID, IMSI, etc.) transmitted from the owner allows the mobile terminal to access the CSG cell from the core network. Send an access permission setting request. In Step ST2203, the CSG cell that has received the access permission setting request performs setting for permitting access from the mobile terminal.

  Next, in ST2204, the user equipment that has registered user access to the CSG cell starts manual search for the CSG cell. In this manual search of the CSG cell, a mobile terminal that does not have a white list is allowed to access the CSG cell registered for user access. By doing in this way, it becomes possible for the mobile terminal being served by the CSG cell registered for user access to perform cell search for the CSG cell and perform cell selection. The mobile terminal that has selected the CSG cell receives a TAC (Tracking Area Code) transmitted from the CSG cell and compares it with the TAC held in the mobile terminal. Since the mobile terminal does not have a white list, the TAC held in the mobile terminal is different from the TAC transmitted from the CSG cell. Conventionally, when the TAC is different as described above, the mobile terminal is not allowed to establish an RRC connection to the CSG cell. Then, access to the CSG cell becomes impossible, and it becomes impossible to transmit a TAU to the core network via the CSG cell. Therefore, the white list cannot be obtained. However, in the method disclosed in the present embodiment, even when the TAC is different at the time of starting the manual search for obtaining this white list, the mobile terminal requests the RRC connection to the CSG cell registered for user access, , TAU (Tracking Area Update) can be requested. In ST2204, the manual search is activated, and the mobile terminal that has selected the CSG cell transmits a request for an RRC connection to the CSG cell. The CSG cell that has received the RRC connection request from the mobile terminal permits establishment of an RRC connection because the mobile terminal is set to permit access in ST2203. In ST2205, the mobile terminal permitted to establish the RRC connection transmits a TAU request to the CSG cell. A number (UE-ID, IMSI, etc.) for identifying the mobile terminal may be sent together with the TAU request message. The CSG cell that has received the TAU request transmits the TAU request to the core network together with a number for identifying the mobile terminal in ST2206 because the access permission is set for the mobile terminal. In ST2207, the core network checks whether the mobile terminal that has transmitted the TAU is a mobile terminal registered in the CSG cell. Specifically, the core network has a list of mobile terminal identification numbers for which user access is permitted for each TAC or CSG-ID, and the mobile terminal identification numbers registered for user access in ST2201 are included in the list. Be rewritten (or deleted or added). The process of ST2207 is performed by the MME 73, for example. For example, this is performed by the idle state mobility management unit 1005-3 of the MME 73 shown in FIG.

  In ST2207, the core network can determine whether the mobile terminal that has transmitted the TAU (Tracking Area Update) is a mobile terminal registered in the CSG cell by using the list. In ST2208, the core network that has determined that the mobile terminal that has transmitted the TAU in ST2207 is a mobile terminal registered in the CSG cell transmits a TAU accept message to the CSG cell. The CSG cell that has received the TAU accept message transmits a TAU accept message to the mobile terminal in ST2209. Further, in ST 2210, the core network transmits a white list to the CSG cell, and the CSG cell that has received it transmits a white list to the mobile terminal in ST 2211. The mobile terminal notified with the white list in ST 2212 stores the white list in its own mobile terminal. Specifically, it is proposed to be stored in SIM / USIM. Here, the white list is described as being transmitted, but it may not be the white list itself, but may be the CSG information of the CSG cell registered in the white list and registered by the mobile terminal for user access. Specifically, CSG-ID, TAI, TAC, etc. can be considered as CSG information. As long as the CSG-ID and the TAI or TAC are associated with each other, any one is sufficient.

  Further, GCI may be used as long as CSG-ID, TAI, or TAC is associated with GCI (Global Cell Identity). Further, instead of the white list itself, a message requesting that the mobile terminal write the TAC or CSG-ID information on the BCCH received through a series of cell search and cell selection processes to the white list may be used. The mobile terminal that has been notified of the white list in ST 2211 stores (registers) the white list in its own mobile terminal in ST 2212. When the CSG-ID is notified instead of the white list in ST2211, the CSG-ID is stored in the white list. When it is requested to write the TAC or CSG-ID information on the BCCH to the white list, the TAC or CSG-ID information is stored in the white list. The mobile terminal that performed whitelist registration in ST2212 can access the CSG cell, not only when manual search is activated. The CSG cell described here may be any CSG cell as long as it is a CSG cell belonging to the same CSG-ID. The method disclosed in the present embodiment can also be applied to a case where a mobile terminal that already has a white list changes (deletes or adds) the white list.

  By performing a manual search method when a user equipment that does not have a white list performs user access registration in the CSG cell as in the sequence shown in FIG. 22, the user equipment becomes part of the non-CSG cell. Even if it does not exist, the white list can be obtained from the CSG cell. In the Home-eNB manual search proposed in 3GPP, as shown in FIG. 21, a mobile terminal that does not have a white list is under the control of a CSG cell registered for user access, and can select the CSG cell during manual search. On the premise. Therefore, the mobile terminal can make a request for establishment of an RRC connection and TAU (Tracking Area Update), which could not be performed conventionally, only to the CSG cell belonging to the CSG-ID of the CSG cell registered for user access. In this case, the mobile terminal can access the CSG cell by manual search and obtain a white list.

Embodiment 4 FIG.
In the future, when a large number of CSG cells are installed and when CSG cells are installed and removed frequently and flexibly, it may not be possible to obtain a whitelist only by the method disclosed in the third embodiment. It will occur. FIG. 23 shows a case where the mobile terminal is not under the control of a non-CSG cell but under the control of a number of CSG cells. The situation shown in the figure may occur when many CSG cells are installed in an apartment, school, company, etc. in the future. As an operation method of the CSG cell, it is considered to promote installation in a place where radio waves from such a non-CSG cell do not reach and enable communication via the CSG cell.

  For example, at present, there are many situations where an apartment room does not receive radio waves from a non-CSG cell. In such a case, a CSG cell is installed in each room, a CSG is configured for each room, and a CSG-ID is given. For example, a mobile terminal owned by a resident in each room may be registered for user access to the CSG in each room. In such a situation, as shown in FIG. 23, the mobile terminal does not receive radio waves from the non-CSG cell, and exists in a place where radio waves from many CSG cells reach. In such a case, depending on the radio wave propagation environment, radio waves from the CSG cell registered for user access may not reach the mobile terminal, or even if received, the received power may be weaker than other CSG cells. To do. Under such circumstances, it becomes impossible to select a CSG cell that the mobile terminal has registered for user access.

  In the above-mentioned proposal in 3GPP (Non-Patent Document 5), when a user equipment that has performed user access registration in a CSG cell does not yet have a whitelist and is in the area of the CSG cell in which user access registration has been performed, Although it is described that TAU is transmitted to the core network through the CSG cell that has performed user access registration by activating manual search, the mobile terminal has registered the user access registered CSG cell (same CSG-ID There is no description about the case where the CSG cell cannot be selected), and there is no description about the case where the TAU is rejected. Therefore, in a situation where the mobile terminal cannot select a CSG cell registered for user access, it is impossible to obtain a white list by the method proposed in 3GPP (Non-Patent Document 5). Problem arises.

  Furthermore, the following problems arise not only when a mobile terminal that does not have a white list registers a white list, but also when a mobile terminal that already has a white list changes (deletes or adds) the white list. . In the above-mentioned proposal in 3GPP, there is no description about a mobile terminal having a white list. Even in the situation as shown in FIG. 23, even if the mobile terminal has a white list, a CSG cell (cell that is not a suitable cell) having a CSG-ID different from the CSG cell to which the mobile terminal has registered user access is selected. May end up. In such a case, there is no description about the case where the mobile terminal cannot select the CSG cell (including the CSG cell having the same CSG-ID) registered for user access, and the case where the TAU is rejected. In the method proposed by 3GPP (Non-Patent Document 5), which is not described at all, there is a problem that it is impossible to obtain a white list. The discussions at 3GPP do not suggest anything about these problems, nor do they provide any solution to these problems.

  In order to solve these problems, in this embodiment, when a mobile terminal that has performed user access registration (hereinafter, including change (deletion, addition)) in a CSG cell performs a manual search, whether or not there is a whitelist. Regardless, not only the CSG cell belonging to the CSG-ID of the CSG cell that performed user access registration, but also other CSG cells can establish RRC connections and transmit TAUs to the core network via the CSG cell. Discloses a method for enabling transmission of a TAU to a core network via a selected CSG cell no matter which CSG cell is selected.

  In FIG. 24, when it is possible to establish an RRC connection not only in the CSG cell belonging to the CSG-ID of the CSG cell that has performed user access registration but also in other CSG cells and to transmit a TAU to the network via the CSG cell Is a sequence diagram when a manual search is performed. The figure shows an LTE communication system using, for example, a Home-eNB. The figure will be described. Here, the mobile terminal performs user access registration with the Home-eNB (C), but the operations from ST2401 to ST2403 are the same as described above, and thus the description thereof is omitted. The mobile terminal in the situation as shown in FIG. 23 activates the home-eNB manual search in ST2404 when the whitelist is registered or changed. The mobile terminal that has started the manual search performs cell search and cell selection in ST2405. In the situation shown in FIG. 23, the mobile terminal selects a CSG cell. Whether the CSG cell selected by the cell is a CSG cell that has performed user access registration, the mobile terminal can establish an RRC connection to the CSG cell and transmit a TAU to the network via the CSG cell. . Therefore, in ST2406, the mobile terminal transmits a request for an RRC connection to a CSG cell (here Home-eNB (A)) that is not a CSG cell (here Home-eNB (C)) registered for user access, and this RRC. The Home-eNB (A) that has received the connection establishment request transmits an establishment permission for the establishment request to the mobile terminal, thereby establishing an RRC connection between the mobile terminal and the Home-eNB (A). Next, in ST2407 and ST2408, the mobile terminal can transmit a TAU request message to the core network via a CSG cell (Home-eNB (A)) that is not a CSG cell registered for user access. Here, the mobile terminal also transmits the mobile terminal identification number. The mobile terminal identification number may be included in the TAU request message, may be combined with the TAU request message, or may be transmitted as a separate message. In addition, a CSG cell that is not a user-registered CSG cell can be manually set in the RRC connection request message and the TAU request message from the mobile terminal so that it can be distinguished from the time when manual search is started. Information indicating that the search is activated may be included. As a result, a CSG cell that is not a CSG cell registered for user access can establish a RRC connection with the mobile terminal, receive a TAU request message from the mobile terminal only when manual search is started, A series of messages such as transmission can be transmitted and received.

  The core network that has received the TAU request message checks whether or not the mobile terminal belongs to the CSG-ID of the Home-eNB (A) based on the received mobile terminal identification number. The method described in ST2207 disclosed in FIG. 22 can be applied to this check method. Since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the core network determined to be inaccessible to the Home-eNB (A) is Home-eNB in ST2410 and ST2411. A TAU reject message for the TAU request is transmitted to the mobile terminal via the eNB (A). The mobile terminal that has received the TAU reject message releases the RRC connection with the Home-eNB (A) in ST2412. Then, in ST2413, the mobile terminal performs cell selection again. Here, the cell may be selected after performing the cell search again. At the time of cell selection again after receiving the TAU reject message, the best cell may be selected again except for the Home-eNB (A) that transmitted the TAU reject message, or the Home-eNB that transmitted the TAU reject message. The best cell including (A) may be selected again. Even when the best cell including the Home-eNB (A) that transmitted the TAU reject message is selected again, the cell selection is performed after performing the cell search again. In some cases, the cell becomes the best cell and another cell is selected.

  The mobile terminal that has selected Home-eNB (B) by reselecting the cell is permitted to establish an RRC connection to a CSG cell that has not been registered for user access, and to transmit a TAU to the network via the CSG cell. Therefore, an RRC connection establishment process is transmitted in ST2414, and a TAU request message is transmitted to the core network in ST2415 and ST2416. However, as in ST2409, since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (B) belongs in ST2417, the core determined to be inaccessible to the Home-eNB (B) In ST2418 and ST2419, the network transmits a TAU reject message for the TAU request to the mobile terminal via the Home-eNB (B). The mobile terminal that has received the TAU reject message releases the RRC connection with the Home-eNB (B) in ST2420. Then, in ST24121, the mobile terminal performs cell selection again as in ST2413. The mobile terminal that has selected Home-eNB (C) by re-selecting the cell, regardless of whether or not user access registration has been performed, requests to establish an RRC connection to the CSG cell, and to the network via the CSG cell Transmission of RRC connection is performed in ST2422, and a TAU request message is transmitted to the core network in ST2423 and ST2424. In ST2425, since the mobile terminal identification number is registered in the CSG-ID to which the Home-eNB (C) belongs, the core network determines that the Home-eNB (C) is accessible, and in ST2426 and ST2427, the Home -A TAU accept message for the TAU request is transmitted to the mobile terminal via the eNB (C). In ST2428, the core network transmits a whitelist to Home-eNB (C). Home-eNB (C) which received the white list transmits a white list to the mobile terminal in ST2429. The mobile terminal to which the white list is transmitted in ST 4730 stores the white list in its own mobile terminal.

  By adopting such a method, even if the CSG cell that has been registered for user access in the initial cell selection is not selected in the manual search of the mobile terminal, the white list will not be unavailable. In the second cell selection, the CSG cell with user access registration is selected, and the mobile terminal can obtain the white list from the core network via the CSG cell with user access registration. .

  As disclosed in the present embodiment, when a manual search is performed in a mobile terminal, regardless of the presence or absence of a white list, not only the CSG cell belonging to the CSG-ID of the CSG cell in which user access registration has been performed, but other CSGs The cell can also establish an RRC connection and transmit TAU to the core network via the CSG cell, and can transmit TAU to the core network via the selected CSG cell regardless of which CSG cell the mobile terminal selects. By adopting the method, it is possible to solve the above-described problem that it becomes impossible to obtain a white list in a situation where the mobile terminal cannot select a CSG cell registered for user access. Become. In addition, when a mobile terminal that already has a white list changes (deletes or adds) the white list, the mobile terminal selects a CSG cell having a CSG-ID different from the CSG cell to which the mobile terminal has registered for user access. In such a situation, it becomes possible to solve the problem that it is impossible to obtain the white list. As a result, it becomes possible to respond to future system requirements in which a large number of CSG cells are installed, and CSG cells are installed and removed frequently and flexibly.

Embodiment 5. FIG.
By performing the method disclosed in the fourth embodiment, it is possible to solve the problem that it becomes impossible to obtain a white list in a situation where the mobile terminal cannot select a CSG cell registered for user access. It becomes possible. In the present embodiment, a method for enabling effective communication even when there are many CSG cells belonging to CSG-IDs that are not registered for user access is disclosed.

  In the situation shown in FIG. 23, when there are a large number of CSG cells belonging to a CSG-ID that the mobile terminal has not registered for user access, when a manual search is performed in the mobile terminal, In cell selection, further cell search or cell selection again, a situation occurs in which CSG cells that are not registered for user access by the mobile terminal are continuously selected. In such a situation, the mobile terminal repeats establishment of an RRC connection for many CSG cells and requests for TAU to the core network via the CSG cells. Further, in future system operation, a situation where there are many mobile terminals as described above is assumed. For example, there is a case where a CSG cell is installed in each classroom of a school, and a student in each classroom registers or changes a white list. In such a case, from more mobile terminals, the mobile terminal will repeatedly establish RRC connections for many CSG cells and repeat TAU requests to the core network via the CSG cells. The number is expected to be enormous. When such a situation occurs, there arises a problem that the use efficiency and signaling efficiency of radio resources are extremely lowered as a system. Furthermore, it takes a lot of time from the cell search to the standby operation, which causes a problem that a large control delay occurs as a system and a problem that the power consumption becomes enormous in the mobile terminal.

  In addition, when the white list of the mobile terminal is rewritten for some reason, or when the mobile terminal receives the contents of the white list transmitted from the core network by mistake when registering or changing the white list The following problems also occur. For example, a case where the mobile terminal erroneously receives the contents of the white list transmitted from the core network when registering or changing the white list will be described. As shown in FIG. 23, in a situation where there are a large number of CSG cells, there is a case where a CSG cell belonging to the CSG-ID of the white list received by mistake is selected. Even in such a case, the mobile terminal may repeatedly establish an RRC connection to the CSG cell belonging to the wrong CSG-ID of the white list or repeatedly request a TAU to the core network via the CSG cell. Become.

  In order to solve these problems, in this embodiment, in addition to the method of Embodiment 4, when the mobile terminal performs a manual search, the CSG-ID of the CSG cell that the mobile terminal has registered for user access Even when an RRC connection is established in a CSG cell different from the CSG cell belonging to and a TAU request is transmitted to the core network via the CSG cell, the core network also sends a TAU reject message to the mobile terminal via the CSG cell. A method of transmitting a whitelist through the CSG cell before transmitting the message is disclosed. FIG. 25 shows a sequence diagram of a method for transmitting a white list before transmitting a TAU reject. The figure will be described. The figure shows an LTE system using, for example, a Home-eNB. Here, the mobile terminal performs user access registration with the Home-eNB (C), but the operations from ST2501 to ST2503 are the same as those described above, and thus description thereof is omitted. A mobile terminal that has started manual search for a CSG cell (here, Home-eNB) in ST2504 performs cell search and cell selection in ST2505.

  In the situation as shown in FIG. 23, when there are a larger number of CSG cells belonging to CSG-IDs that the mobile terminal has not registered for user access, the mobile terminal selects a CSG cell. As disclosed in the fourth embodiment, whether the CSG cell selected by the cell is a CSG cell that has performed user access registration, the mobile terminal can establish an RRC connection to the CSG cell, and TAU can be transmitted to the network via the network. Thereby, in ST2506, the mobile terminal transmits a request for an RRC connection to a CSG cell (here Home-eNB (A)) that is not a CSG cell (here Home-eNB (C)) registered for user access. The Home-eNB (A) that has received the RRC connection establishment request transmits an establishment permission for the establishment request to the mobile terminal, so that the RRC connection is established between the mobile terminal and the Home-eNB (A). . Next, in ST2507 and ST2508, the mobile terminal can transmit a TAU request message to the core network via a CSG cell (Home-eNB (A)) that is not a CSG cell registered for user access. Here, the mobile terminal also transmits the mobile terminal identification number. The mobile terminal identification number may be included in the TAU request message, may be combined with the TAU request message, or may be transmitted as a separate message. In addition, a CSG cell that is not a user-registered CSG cell can be manually set in the RRC connection request message and the TAU request message from the mobile terminal so that it can be distinguished from the time when manual search is started. Information indicating that the search is activated may be included. As a result, a CSG cell that is not a CSG cell registered for user access can establish a RRC connection with the mobile terminal, receive a TAU request message from the mobile terminal only when manual search is started, A series of messages such as transmission can be transmitted and received. The core network that has received the TAU request message checks whether or not the mobile terminal belongs to the CSG-ID of the Home-eNB (A) based on the received mobile terminal identification number. The method described in ST2207 disclosed in FIG. 22 can be applied to this check method. Since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the core network determines that the mobile terminal cannot access the Home-eNB (A).

  In the method disclosed in the fifth embodiment, even when the mobile terminal determines that the mobile terminal cannot access the Home-eNB (A), before transmitting the TAU reject, the core terminal may transmit the Home-eNB ( A white list of the mobile terminal is transmitted to A). The Home-eNB (A) that has received the white list of the mobile terminal transmits a white list to the mobile terminal in ST2511. The mobile terminal to which the white list is transmitted in ST5212 stores the white list in its own mobile terminal. In ST2513 and ST2514, the core network that has transmitted the whitelist of the mobile terminal to the Home-eNB (A) in ST2510 sends a TAU reject message for the TAU request to the mobile terminal via the Home-eNB (A). Send. The mobile terminal that has received the TAU reject message releases the RRC connection with the Home-eNB (A) in ST2515.

  By adopting such a method, in the manual search of the mobile terminal, the CSG cell that has been registered for user access in the cell selection is not selected, and in the initial cell selection, the mobile terminal The white list can be obtained from the core network via a CSG cell that is not registered. Further, even if only the best cell selection is allowed in the cell selection, the use of this method makes it possible to reliably obtain the white list from the selected best cell.

  As a method of manual search, not only cell search and activation before cell selection but also cell identification number or TAC or CSG-ID of one or more cells suitable for cell search selection criteria in cell search to the mobile terminal The user may manually select a desired cell from the one or a plurality of cells, and an RRC connection establishment and TAU request may be transmitted to the desired cell. If the mobile terminal manually selects a CSG cell that the user terminal has registered for user access as a desired cell, it is necessary to perform transmission / reception and transmission of a TAU request message to establish a RRC connection with the CSG cell that the user terminal has not registered for user access. Disappears.

  However, since it is necessary to receive broadcast information such as SIB1 from the cell as shown in ST1205 of FIG. 12 in order to receive the cell identification number, TAC, or CSG-ID of the cell, it takes time. End up. In a situation where a large number of CSG cells are installed, in cell search, it is considered that the number of cells suitable for the cell search selection criteria is enormous, receiving broadcast information of all those cells, cell identification numbers, Alternatively, displaying a TAC or CSG-ID or the like on a mobile terminal still takes an enormous amount of time. Further, when the mobile terminal performs a cell search for a CSG cell suitable for the cell search selection criteria, it is required to store the resolution for sorting the CSG, the broadcast information of the CSG cell in the mobile terminal, and the like. In a situation where a large number of CSG cells are installed, the number of cells suitable for cell search selection criteria may be enormous in the cell search, and the resolution for receiving all these cells, Storing the received broadcast information complicates the receiving unit of the mobile terminal, and a storage processing unit with a huge storage capacity must be provided in the mobile terminal. Therefore, the mobile terminal becomes larger and the manufacturing cost increases. In order to avoid such a problem, in the cell search process, methods such as limiting the search time or limiting the number of cells to be searched are used. For example, the best cell may be selected within a certain time limit or from a certain limited number of cells.

  When such a method is used, in the cell search, the cell identification number or TAC or CSG-ID of one or more cells suitable for the cell search selection criterion is displayed on the mobile terminal, and the one or more cells are displayed. In a method in which a mobile terminal manually selects a CSG cell registered for user access from within, the CSG cell cannot be searched within the search time limit, or the cell to be searched is limited, There arises a problem that the CSG cell does not enter. In such a case, no matter how much manual search is performed, the mobile terminal cannot select a CSG cell registered for user access, and the white list cannot be obtained.

  Even in such a case, the above-described problem can be solved by applying the present embodiment. When a mobile terminal that has performed user access registration (hereinafter, including change (deletion, addition)) in the CSG cell performs a manual search, the CSG- of the CSG cell in which the user access registration has been performed is performed regardless of the presence or absence of the white list. Not only the CSG cell belonging to the ID but also other CSG cells can establish RRC connections and transmit TAU to the core network via the CSG cell, and the selected CSG cell can be selected regardless of which CSG cell the mobile terminal selects. By enabling TAU to be transmitted to the core network via the cell search, the CSG cell cannot be searched within the search time limit in the cell search, or the cell to be searched is limited, and the CSG cell is included in the cell. Even if it has not been received, by selecting another CSG cell, the other CSG cell RRC connection establishment and TAU transmission to the core network via the CSG cell becomes possible, and the core network transmits the TAU reject message to the mobile terminal via the CSG cell. The white list can be transmitted, and the mobile terminal can obtain the white list.

  By adopting the method disclosed in the present embodiment, there are a large number of CSG cells belonging to CSG-IDs in which the mobile terminal is not registered for user access, or in such a situation. If there are a large number of mobile terminals, the white list of the mobile terminal may be rewritten for some reason, or the mobile terminal may mistakenly specify the content of the white list sent from the core network when registering or changing the white list. When the mobile terminal performs a manual search in the case of reception, a situation occurs in which CSG cells continue to be selected endlessly, and the mobile terminal establishes an RRC connection to many CSG cells, It is possible to solve the problem that the TAU request is repeatedly used through the cell to the core network. By eliminating these problems, it is possible to eliminate an extreme decrease in radio resource usage efficiency and signaling efficiency in future system operation. Furthermore, it is possible to shorten the time from the cell search to the start of the standby operation, and it is possible to solve the problem that a large control delay occurs as a system. Furthermore, when a manual search is performed in the mobile terminal, a situation in which CSG cells are continuously selected can be solved, so that power consumption of the mobile terminal can be reduced.

  Hereinafter, a modification of the fifth embodiment described above will be described. In the fifth embodiment, in addition to the method of the fourth embodiment, when a mobile terminal performs a manual search, the mobile terminal uses a CSG cell different from the CSG cell belonging to the CSG-ID of the CSG cell registered for user access. Even when an RRC connection is established and a TAU request is transmitted to the core network through the CSG cell, the core network transmits the TAU reject message to the mobile terminal through the CSG cell. Disclosed is a method for sending a whitelist via the Internet. In this modification, when a core network transmits a TAU reject message to the mobile terminal via the CSG cell, a method of transmitting a white list on the TAU reject message is disclosed.

  FIG. 26 shows a sequence diagram in the method disclosed in the first modification. Since this method is almost the same as the method described with reference to FIG. 25 of the fifth embodiment, only different parts will be described here. In ST2609, based on the received mobile terminal identification number, the core network that has checked whether or not the mobile terminal belongs to the CSG-ID of Home-eNB (A), the mobile terminal is Home-eNB ( It is determined that access to A) is impossible. In ST2610, the core network transmits a TAU reject message including a whitelist notification request to Home-eNB (A). The Home-eNB (A) that has received this message transmits a TAU reject message including a whitelist notification to the mobile terminal in ST2611. The mobile terminal that has received the TAU reject message including the whitelist notification in ST2611 stores the whitelist in the mobile terminal in ST2612. In ST2613, the RRC connection between the mobile terminal and Home-eNB (A) is released. By adopting such a method, in addition to the effects of the fifth embodiment, it is possible to reduce signaling for whitelist transmission performed before the core network transmits the TAU reject message to the mobile terminal via the CSG cell. It becomes possible. Furthermore, since the TAU reject message is transmitted / received in response to the TAU request message, an effect of improving compatibility with the conventional TAU request and reject method can be obtained.

Embodiment 6 FIG.
In order to solve the problem described in the fifth embodiment, in this embodiment, when the mobile terminal receives TAU reject messages continuously (n ≧ 1) from the same cell, the mobile terminal Discloses a method for prohibiting establishment of an RRC connection to the cell and transmission of a TAU request message.

  FIG. 27 shows a sequence diagram of a method in which when a TAU reject message is received once from the same cell, the mobile terminal prohibits establishment of an RRC connection to the cell. The figure will be described. The figure shows a case of an LTE system using, for example, a Home-eNB. Here, the mobile terminal performs user access registration with the Home-eNB (B), but since ST2701 to ST2703 operate in the same manner as described above, a description thereof is omitted. A mobile terminal that has started manual search for a CSG cell (here, Home-eNB) in ST2704 performs cell search and cell selection in ST2705. In the situation as shown in FIG. 23, when there are a large number of CSG cells belonging to CSG-IDs that the mobile terminal has not registered for user access, the mobile terminal is assigned a CSG-ID that is not registered for user access. In many cases, the CSG cell to which the cell belongs is selected. As disclosed in the fourth embodiment, whether the CSG cell selected by the cell is a CSG cell that has performed user access registration, the mobile terminal can establish an RRC connection to the CSG cell, and TAU can be transmitted to the network via the network. Thereby, in ST2706, the mobile terminal transmits a request for an RRC connection to a CSG cell (here Home-eNB (A)) which is not a CSG cell (here Home-eNB (C)) registered for user access, The Home-eNB (A) that has received the RRC connection establishment request transmits an establishment permission for the establishment request to the mobile terminal, thereby establishing an RRC connection between the mobile terminal and the Home-eNB (A).

  Next, in ST2707 and ST2708, the mobile terminal transmits a TAU request message to the core network via the Home-eNB (A). Here, the mobile terminal also transmits the mobile terminal identification number. The mobile terminal identification number may be included in the TAU request message, may be combined with the TAU request message, or may be transmitted as a separate message. In ST2709, the core network that has received the TAU request message checks whether the mobile terminal belongs to the CSG-ID of Home-eNB (A) based on the received mobile terminal identification number. The method described in ST2207 disclosed in FIG. 22 can be applied to this check method. Since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the core network determines that the mobile terminal cannot access the Home-eNB (A). In ST2710 and ST2711, the core network transmits a TAU reject message to the mobile terminal via the Home-eNB (A). In ST2712, the mobile terminal that has received the TAU reject message releases the RRC connection with the Home-eNB (A). In ST2713 that has received the TAU reject message once, the mobile terminal performs processing for prohibiting establishment of an RRC connection to the Home-eNB (A). Specifically, for example, an RRC connection establishment prohibited cell list is provided in the mobile terminal, and the mobile terminal stores a home-eNB (A) cell identification number (PCI, Cell-ID, GCI, etc.) in the list. To do. Then, before establishing the next RRC connection, the list is checked to determine whether the cell is stored in the list. In the case of a cell stored in the list, establishment of an RRC connection is prohibited. Here, CSG-ID and TAC may be stored in the list, and the CSG-ID and TAC may be stored in association with the cell identification number. In this way, next, when Home-eNB (A) is selected again in the future by cell search and cell selection, the mobile terminal does not establish RRC connection with Home-eNB (A). it can. The mobile terminal that has not been able to obtain the white list until ST2713 newly performs cell search and cell selection in ST2714.

  Here, when Home-eNB (A) is selected again, since the establishment of the RRC connection is prohibited, cell selection is performed from cells other than Home-eNB (A). In ST2715, the mobile terminal that has selected Home-eNB (B) by cell selection performs processing for establishing an RRC connection with Home-eNB (B). After the RRC connection establishment process is performed, in ST2716 and ST2717, the mobile terminal transmits a TAU request message to the core network via the Home-eNB (B). In ST2718, the core network that has received the TAU request message determines whether or not the mobile terminal belongs to the CSG-ID (TAC) of Home-eNB (B) based on the mobile terminal identification number received together. Check. The method described in ST2207 disclosed in FIG. 22 can be applied to this check method. Since the mobile terminal identification number is registered in the CSG-ID to which the Home-eNB (B) belongs, the core network determines that the mobile terminal can access the Home-eNB (B). In ST2719 and ST2720, the core network transmits a TAU accept message to the mobile terminal via the Home-eNB (B). In ST2721, ST2722, the core network transmits a whitelist to the mobile terminal via the Home-eNB (B). The mobile terminal that has been notified of the white list in ST 2723 stores the white list in its own mobile terminal.

  In the example of the present embodiment, the process for prohibiting the establishment of the RRC connection to the cell from which the mobile terminal has received the TAU reject message has been described. The establishment of the RRC connection to the cell may be prohibited. Moreover, although the process for prohibiting establishment of an RRC connection has been described, it may be a process for prohibiting transmission of a TAU request message or a process for prohibiting both. In addition, the process for prohibiting the establishment of the RRC connection to the cell in which the mobile terminal has received the TAU reject message once has been described. It may be prohibited. The number of times the TAU reject message is continuously received from the same cell may be transmitted from the cell as broadcast information or may be determined in advance.

  By adopting the method disclosed in the present embodiment, there are a large number of CSG cells belonging to CSG-IDs that are not registered for user access by the mobile terminal, or there are many mobile terminals in such a situation. If the mobile terminal exists, the whitelist of the mobile terminal is rewritten for some reason, or the mobile terminal receives the content of the whitelist sent from the core network by mistake when registering or changing the whitelist. When a manual search is performed in the mobile terminal, a situation occurs in which the CSG cell is continuously selected, and the mobile terminal establishes an RRC connection for many CSG cells, Thus, it is possible to solve the problem that the TAU request to the core network is repeated unnecessarily. By eliminating these problems, it is possible to eliminate an extreme decrease in radio resource usage efficiency and signaling efficiency in future system operation. Furthermore, it is possible to shorten the time from the cell search to the start of the standby operation, and it is possible to solve the problem that a large control delay occurs as a system. Furthermore, when a manual search is performed in the mobile terminal, a situation in which CSG cells are continuously selected can be solved, so that power consumption of the mobile terminal can be reduced.

  Next, a first modification of the sixth embodiment described above will be described. In the first modified example, a method is disclosed in which the core network transmits information to the mobile terminal with information on prohibition of establishment of RRC connection and prohibition of transmission of TAU request message in the TAU reject message.

  This will be described with reference to FIG. A part of FIG. 27 may be changed as follows. The description of the same operation as that of the sixth embodiment is omitted. In ST2709, the core network that has received the TAU request message checks whether the mobile terminal belongs to the CSG-ID of Home-eNB (A) based on the received mobile terminal identification number. Since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the core network determines that the mobile terminal cannot access the Home-eNB (A). In ST2710 and ST2711, the core network transmits a TAU reject message to the mobile terminal via the Home-eNB (A). At this time, the core network puts information on prohibition of establishment of an RRC connection to the Home-eNB (A) and prohibition of transmission of a TAU request message in the TAU reject message. Specifically, a 1-bit indicator may be provided so that “1” is set for prohibition and “0” is set for permission (or vice versa). The mobile terminal that has received this releases the RRC connection with the Home-eNB (A) in ST2712, and performs the process of prohibiting the establishment of the RRC connection to the Home-eNB (A) in ST2713.

  By doing in this way, it becomes possible to acquire the same effect as Embodiment 6. Furthermore, it becomes possible for the core network to determine whether to prohibit RRC connection establishment and TAU request message transmission. As a result, the core network can appropriately cause the mobile terminal to perform the prohibition process according to the situation at that time, such as the signaling load amount and the CSG cell arrangement situation, so that the operation as a system becomes flexible. can get.

  Next, a second modification of the sixth embodiment described above will be described. In the description of the sixth embodiment and the first modification 1, when the mobile terminal receives a TAU reject message, the mobile terminal prohibits establishment of an RRC connection to the cell and prohibits transmission of a TAU request message. Disclosed. However, when the mobile terminal newly registers (updates) user access to the CSG cell in the prohibited state as described above, a problem may occur.

  If the mobile terminal is prohibited from establishing an RRC connection and transmitting a TAU request message to the CSG-ID of the CSG cell before registering a new user access, the mobile terminal is newly added to the CSG cell. Even if the access registration is made, it is considered that the establishment of the RRC connection and the transmission of the TAU request message are prohibited for the CSG cell and the access becomes impossible. In order to solve such a problem, as a second modification, it is disclosed to provide a timer for canceling the RRC connection establishment prohibition and the TAU request message transmission prohibition. The value of the timer may be determined in advance as a value common to all cells, or may be broadcast by broadcast information of the CSG cell.

  When broadcast by the broadcast information of the CSG cell, the value may be different for each cell. This enables flexible operation for each cell. Further, it may be transmitted by being included in the TAU reject message shown in ST2710 and ST2711 of FIG. This may be the first TAU reject message, or may be the TAU reject message immediately before the establishment of the RRC connection and the transmission of the TAU request message are prohibited. In this case, it becomes possible for the core network to set the timer value, and furthermore, it is possible to set it individually for each mobile terminal. It is possible to set the timer value as appropriate according to the situation unique to the mobile terminal. The start of the timer may be, for example, transmission of a TAU request message to a certain CSG cell. The timer may end when the timer expires, when a TAU accept message is received from the CSG cell, or when user access registration (update) is performed in a new CSG cell. FIG. 28 discloses an example of processing in the mobile terminal when a timer is provided.

  The mobile terminal that has started the home-eNB (CSG cell) manual search performs cell search and cell selection in ST2801. In ST2802, the mobile terminal determines whether the timer is running because the CSG-ID (TAC) of the cell-selected Home-eNB is TAU prohibited. For example, specifically, a CSG-ID (TAC) and a timer set in the CSG-ID (TAC) may be placed on the prohibition list shown in the process of ST2713 in FIG. The determination may be made by looking at the timer in the list. When the timer is running, TAU prohibition is performed on the CSG cell selected by the cell, so a cell that is not a CSG-ID (TAC) whose TAU is prohibited in ST2803 is cell-searched and selected, and the process proceeds to ST2804. On the other hand, if a CSG cell whose timer is not running is selected in ST2802, the CSG cell is not TAU-prohibited, so the process proceeds to ST2804, and a TAU request is transmitted to the home-eNB that has selected the cell. In ST2805, using the transmission of the TAU request as a trigger, a timer is set for the CSG-ID (TAC) of the Home-eNB that has requested the TAU. In ST2806, the NAS message for the TAU request message is received from the Home-eNB.

  In ST2807, the mobile terminal determines whether the NAS message received in ST2806 is a TAU reject or a TAU accept. In the case of TAU acceptance, the process proceeds to ST2808, where the timer ends and the timer is reset. In ST2809, the whitelist registration process is performed, and the process proceeds to a normal process. On the other hand, if it is determined that the TAU is rejected in ST2807, the process proceeds to ST2810, and it is determined again whether the timer period has expired. If the timer period has expired in ST2810, the mobile terminal moves to ST2812, permits TAU for the CSG-ID (TAC) of the Home-eNB that requested the TAU, resets the timer in ST2813, and then performs cell search, cell Move to selection. If the timer period has not expired in ST2810, the mobile terminal makes a transition to cell search and cell selection again while prohibiting TAU for the CSG-ID (TAC) of the Home-eNB that requested the TAU. Whether or not the timer period has ended may be included not only in the case shown in FIG. 28 but also in the processing in ST2802, for example. If the timer period has expired, after performing the processing of ST2812, ST2813, the process may move to ST2804. If the timer period has not expired, after performing the processing of ST2811, the process may move to ST2803.

  As described above, by providing a timer that cancels prohibition of establishment of RRC connection and prohibition of transmission of TAU request message, the same effects as those described in the sixth embodiment and the first modification can be obtained. . Further, it is possible to solve the problem that access becomes impossible when the mobile terminal newly performs user access registration (update) to the CSG cell. This makes it possible to construct a more stable system.

  In the sixth embodiment described above, LTE and UMTS using Home-eNB and Home-NB using CSG have been described. However, the present invention is also applicable to UMTS that uses Home-NB in which CSG is not used. In the case of UMTS using Home-NB in which CSG is not used, when the mobile terminal accesses the Home-eNB registered for user access and the access is successful, the Home-NB sends a cell identification number (Cell Identity) of the Home-NB. , PCI, GCI, etc.) and register it in a white list (referred to as a cell identification number white list in the case of UMTS) in the mobile terminal. Also in this case, when Home-NB different from Home-NB registered by the mobile terminal by the cell search or cell selection is continuously selected, the mobile terminal cannot receive the cell identification number registered by the user access. Or it may take time to receive.

  In order to solve such a problem, it is possible to apply the method of Embodiment 6 also to UMTS using Home-NB in which CSG is not used. When the mobile terminal receives the TAU reject message, the mobile terminal prohibits establishment of an RRC connection to the cell and prohibits transmission of a TAU request message. The Home-NB that is different from the Home-NB that received the message is selected, so that the Home-NB different from the Home-NB to which the mobile terminal has registered user access is not continuously selected.

  In the case of a UMTS communication system, an RNC is provided between the base station (Home-NB, NB) and the core network, and RRC messages such as RRC connection requests are transmitted and received between the mobile terminal and the RNC. The NAS message such as a TAU request may be transmitted and received from the mobile terminal to the core network via the base station (Home-NB, NB) and the RNC. By doing so, the present invention can be applied to a UMTS communication system in which Home-NB is used as a CSG cell. Therefore, the mobile terminal does not perform useless cell search and cell selection, and it takes a lot of time until the mobile terminal enters the standby operation from the cell search, and there is a problem that a large control delay occurs as a system. Can solve the problem that power consumption becomes enormous. In the future, it becomes possible to construct a mobile communication system that can meet the demands for dealing with cases where the number of Home-NB installations becomes large or the installation and removal of Home-NBs are frequent and flexible.

Embodiment 7 FIG.
In order to eliminate the problems described in the fifth embodiment, in this embodiment, the core network continuously transmits TAU reject messages n times (an integer of n ≧ 1) to the same mobile terminal. In this case, the core network discloses a method of transmitting the white list before transmitting the nth TAU reject message.

  FIG. 29 shows a sequence diagram of a method in which the core network transmits a whitelist before transmitting the nth TAU reject message when transmitting TAU reject messages twice to the same mobile terminal. Show. The figure will be described. The figure shows an LTE system using, for example, a Home-eNB. Here, the mobile terminal performs user access registration with the Home-eNB (B), but the operation from ST 2901 to ST 2903 is the same as described above, and thus the description is omitted. A mobile terminal that has started manual search for a CSG cell (here, Home-eNB) in ST2904 performs cell search and cell selection in ST2905. In the situation as shown in FIG. 23, when there are a large number of CSG cells belonging to CSG-IDs that the mobile terminal has not registered for user access, the mobile terminal is assigned a CSG-ID that is not registered for user access. In many cases, the CSG cell to which the cell belongs is selected. As disclosed in the fourth embodiment, whether the CSG cell selected by the cell is a CSG cell that has performed user access registration, the mobile terminal can establish an RRC connection to the CSG cell, and TAU can be transmitted to the network via the network. Accordingly, in ST2906, the mobile terminal transmits an RRC connection request message to a CSG cell (here Home-eNB (A)) that is not a CSG cell (here Home-eNB (C)) registered for user access. The Home-eNB (A) that has received the RRC connection request message transmits permission for this request to the mobile terminal, thereby establishing an RRC connection between the mobile terminal and the Home-eNB (A).

  Next, in ST2907 and ST2908, the mobile terminal transmits a TAU request message to the core network via the Home-eNB (A). Here, the mobile terminal also transmits the mobile terminal identification number. The mobile terminal identification number may be included in the TAU request message, may be transmitted together with the TAU request message, or may be transmitted as another message. In ST2909, the core network that has received the TAU request message checks whether or not the mobile terminal belongs to the CSG-ID of Home-eNB (A) based on the received mobile terminal identification number. The method described in ST2207 disclosed in FIG. 22 can be applied to this check method. Since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the core network determines that the mobile terminal cannot access the Home-eNB (A). The core network that has determined that the mobile terminal cannot access the Home-eNB (A) further counts the number of rejections to the mobile terminal (n = 1). In ST2910 and ST2911, the core network transmits a TAU reject message to the mobile terminal via the Home-eNB (A). In ST2912, the mobile terminal that has received the TAU reject message releases the RRC connection with the Home-eNB (A). In Step ST2913, the user equipment that has not been able to obtain the white list until ST2912 performs new cell search and cell selection. Here, when Home-eNB (A) is selected again, an RRC connection is established again with Home-eNB (A) in ST2914. Next, in ST2915 and ST2916, the mobile terminal transmits a TAU request message to the core network via the Home-eNB (A). Similarly, the mobile terminal also transmits a mobile terminal identification number.

  In ST2917, the core network that has received the TAU request message checks whether or not the mobile terminal belongs to the CSG-ID of Home-eNB (A) based on the received mobile terminal identification number. Similar to ST2909, since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the core network cannot access the Home-eNB (A). judge. The core network that has determined that the mobile terminal cannot access the Home-eNB (A) increments the number of rejections to the mobile terminal by 1 (n = 2). Since the number of rejections to the same mobile terminal is 2, the core network transmits a whitelist registration message before transmitting the second TAU reject message. In ST2918 and ST2919, the core network transmits a whitelist to the mobile terminal via the Home-eNB (B). The mobile terminal notified of the white list in ST2920 stores the white list in its own mobile terminal. In ST2921, ST2922, the core network that has transmitted the whitelist of the mobile terminal to the Home-eNB (A) in ST2918 moves the second TAU reject message for the TAU request via the Home-eNB (A). Send to the terminal. The mobile terminal that has received the TAU reject message releases the RRC connection with the Home-eNB (A) in ST2923. The number of times the TAU reject message is continuously transmitted to the same mobile terminal may be determined in advance, but may be determined flexibly by the core network. Since the core network determines flexibly, it is possible to send a whitelist to the mobile terminal as appropriate according to the situation such as the amount of signaling load and the reception quality of the mobile terminal, so the operation as a system is flexible. The effect of becoming.

  By adopting the method disclosed in the present embodiment, there are a large number of CSG cells belonging to CSG-IDs that are not registered for user access by the mobile terminal, or there are many mobile terminals in such a situation. If the mobile terminal exists, the whitelist of the mobile terminal is rewritten for some reason, or the mobile terminal receives the content of the whitelist sent from the core network by mistake when registering or changing the whitelist. When a manual search is performed in the mobile terminal, a situation occurs in which the CSG cell is continuously selected, and the mobile terminal establishes an RRC connection for many CSG cells, Thus, it is possible to solve the problem that the TAU request to the core network is repeated unnecessarily. By eliminating these problems, it is possible to eliminate an extreme decrease in radio resource usage efficiency and signaling efficiency in future system operation. Furthermore, it is possible to shorten the time from the cell search to the start of the standby operation, and it is possible to solve the problem that a large control delay occurs as a system. Furthermore, when a manual search is performed in the mobile terminal, a situation in which CSG cells are continuously selected can be solved, so that power consumption of the mobile terminal can be reduced.

Embodiment 8 FIG.
In Embodiments 4 to 7 described above, the TAU reject message transmitted from the core network to the mobile terminal is established by establishing an RRC connection with the CSG cell belonging to the CSG-ID to which the mobile terminal is not registered for user access. Disclosed the method used. However, in any of these cases, it is necessary to establish an RRC connection between a mobile terminal and a CSG cell belonging to a CSG-ID that the mobile terminal has not registered for user access. NAS messages such as a TAU request must be transmitted to and received from each other.

  Therefore, a method of registering a white list using an RRC connection reject message for an RRC connection request message transmitted by a mobile terminal, instead of using a TAU reject message transmitted from the core network to the mobile terminal, is disclosed. This eliminates the need to send and receive NAS messages such as establishment of RRC connections and TAU requests. For example, in the method disclosed in the sixth embodiment, instead of using the TAU reject message transmitted from the core network to the mobile terminal, the RRC connection reject message corresponding to the RRC connection request message transmitted from the mobile terminal is used. A method for registering a list is disclosed. When the mobile terminal receives RRC connection reject messages from the same cell n times (integers of n ≧ 1) continuously, the mobile terminal prohibits RRC connection requests to the cell.

  FIG. 30 shows a sequence diagram of a method in which when a RRC connection reject message is received once from the same cell, the mobile terminal prohibits an RRC connection request to the cell. The figure will be described. The figure shows an LTE system using, for example, a Home-eNB. Here, the mobile terminal performs user access registration with the Home-eNB (B), but the operation from ST3001 to ST3003 is the same as described above, and thus the description is omitted. In ST3004 and ST3005, the core network transmits information on CGS-ID (TAC) of each Home-eNB and identification number of the mobile terminal belonging to the CSG-ID to all CSG cells (here, Home-eNB). deep. For example, the core network transmits information on mobile terminal identification numbers belonging to the CSG-ID of the Home-eNB (B) to the Home-eNB (B). Information on the mobile terminal identification number belonging to the CSG-ID of Home-eNB (A) is transmitted. As a specific example of such information, a list in which mobile terminal identification numbers belonging to the CSG-ID are described may be used. The list corresponding to the CSG-ID of each Home-eNB is sent from the core network to each Home-eNB.

  The mobile terminal that has started the home-eNB manual search in ST3006 performs cell search and cell selection in ST3007. In the situation as shown in FIG. 23, when there are a large number of CSG cells belonging to CSG-IDs that the mobile terminal has not registered for user access, the mobile terminal is assigned a CSG-ID that is not registered for user access. In many cases, the CSG cell to which the cell belongs is selected. In the present embodiment, it is possible for the mobile terminal to transmit a request message for an RRC connection to the CSG cell regardless of whether the CSG cell selected by the cell is a CSG cell that has performed user access registration. The mobile terminal also transmits a mobile terminal identification number. The mobile terminal identification number may be included in the RRC connection request message or may be combined with the RRC connection request message. Accordingly, in ST3008, the mobile terminal transmits a request for an RRC connection to a CSG cell (here Home-eNB (A)) that is not a CSG cell (here Home-eNB (B)) registered for user access. In ST3009, the Home-eNB (A) that has received this RRC connection request also belongs to the CSG-ID of Home-eNB (A) based on the received mobile terminal identification number. Check if. This check determines whether or not the mobile terminal identification number is included in the mobile terminal identification number list belonging to the CSG-ID of Home-eNB (A) transmitted from the core network in ST3008.

  Since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the Home-eNB (A) determines that the mobile terminal cannot access the Home-eNB (A). To do. In ST3010, the Home-eNB (A) transmits an RRC connection reject message to the mobile terminal. In Step ST3011, the mobile terminal that has received the RRC connection reject message once performs processing for prohibiting transmission of the RRC connection request message to the Home-eNB (A). Specifically, for example, an RRC connection request transmission prohibited cell list is provided in the mobile terminal, and the mobile terminal stores a home-eNB (A) cell identification number (PCI, Cell-ID, GCI, etc.) in the list. To do. The list is checked before the next RRC connection request transmission, and it is determined whether or not the cell is stored in the list. In the case of a cell stored in the list, transmission of an RRC connection request is prohibited. Here, the CSG-ID and TAC of the CSG cell may be stored in the list, and the CSG-ID and TAC may be stored in association with the CSG cell identification number. By doing in this way, when Home-eNB (A) is selected again in the future by cell search and cell selection, the mobile terminal does not transmit an RRC connection request to Home-eNB (A). You can

  The mobile terminal that has not been able to obtain the whitelist until ST3011, performs new cell search and cell selection in ST3012. Here, when Home-eNB (A) is selected again, since the transmission of the RRC connection request is prohibited, cell selection is performed from cells other than Home-eNB (A). In ST3013, the mobile terminal that has selected Home-eNB (B) by cell selection transmits an RRC connection request message to Home-eNB (B). In ST3014, the Home-eNB (B) that has received the TAU request message, based on the received mobile terminal identification number, the mobile terminal uses the CSG-ID (TAC) of the Home-eNB (B). Check if it belongs. The method described above can also be applied to this check method. Since the mobile terminal identification number is registered in the CSG-ID to which the Home-eNB (B) belongs, the Home-eNB (B) determines that the mobile terminal can access its own cell. The Home-eNB (B) that has determined that the mobile terminal can access its own cell may notify the mobile terminal of the white list in ST3015 before transmitting the RRC connection accept message. The mobile terminal that has received the white list in ST3016 stores the white list in its own mobile terminal. The Home-eNB (B) that has transmitted the white list to the mobile terminal transmits an RRC connection accept message in ST3017. As a result, an RRC connection is established between the mobile terminal and the Home-eNB (B) (ST3018). Then, in ST3019 and ST3020, the mobile terminal transmits a TAU request message to the core network via the Home-eNB (B). Here, the mobile terminal also transmits a mobile terminal identification number.

  The core network that has received the TAU request message also checks the CSG-ID (TAC) in ST3021 based on the received mobile terminal identification number. In ST3021, the core network that has confirmed that the mobile terminal belongs to the CSG-ID (TAC) of the Home-eNB (B), accepts the TAU acceptance to the mobile terminal in ST3022, ST3023, and the Home-eNB (B). Send through. In ST3004 and ST3005, the core network transmits the CGS-ID (TAC) of each Home-eNB and the identification number of the mobile terminal belonging to the CSG-ID to all CSG cells (here, Home-eNB). However, the mobile terminal identification number information belonging to each CSG-ID may be transmitted to the HeNBGW connected to the CSG cell belonging to the CSG-ID. The HeNBGW may transmit the information on the mobile terminal identification number belonging to each received CSG-ID to the CSG cell having the same CSG-ID connected to the own HeNB. Also, the process of transmitting the received information on the mobile terminal identification numbers belonging to the respective CSG-IDs to the CSG cell having the same CSG-ID connected to the own HeNB is performed by the HeNBGW from the mobile terminal in ST3008. When the CSG cell that has received the RRC connection request is sent a message requesting information on the mobile terminal identification number belonging to the CSG-ID of the own CSG cell to the HeNBGW, and the HeNBGW receives the message It may be done.

  In the present embodiment, the process for prohibiting the RRC connection request for the CSG cell from which the mobile terminal has received the RRC connection reject message has been described. However, all the mobile terminals belonging to the CSG-ID of the cell from which the RRC connection reject message has been received. The RRC connection request to the cell may be prohibited. Moreover, although the process which prohibits the request | requirement of the RRC connection to the CSG cell which received the RRC connection rejection message once for a mobile terminal was demonstrated, when an RRC connection rejection message is received several times continuously from the same cell, an RRC connection is received. This request may be prohibited. The number of times the RRC connection reject message is continuously received from the same cell may be transmitted from the cell by broadcast information or may be determined in advance. The white-list notification is performed before the Home-eNB transmits the RRC connection accept. After receiving the STAU3 TAU accept, the white list moves from the core network via the CSG cell. You may make it transmit to a terminal.

  Next, for example, in the method disclosed in the fifth embodiment or the seventh embodiment, the RRC connection for the RRC connection request message transmitted by the mobile terminal is used instead of using the TAU reject message transmitted from the core network to the mobile terminal. A method for transmitting a white list using a reject message is disclosed. In Embodiments 5 and 7, it is necessary to transmit the white list of the mobile terminal from the CSG cell belonging to the CSG-ID to which the mobile terminal is not registered for user access. For this reason, the core network transmits all CSG-IDs (TACs) and identification number information of mobile terminals belonging to the CSG-IDs to all CSG cells.

  FIG. 31 shows a sequence diagram of a method in which a CSG cell belonging to a CSG-ID to which a user equipment has not registered user access transmits a whitelist before transmitting an RRC connection reject message. FIG. 31 shows a case of an LTE system using, for example, Home-eNB. Here, the mobile terminal performs user access registration with the Home-eNB (C), but the operation from ST3101 to ST3103 is the same as described above, and thus the description thereof is omitted. In ST3104, the core network transmits information on all CGS-IDs (TAC) and identification numbers of mobile terminals belonging to the CSG-ID to all CSG cells (here, all Home-eNBs). As a specific example of such information, a list in which mobile terminal identification numbers belonging to the CSG-ID are described may be used. The list corresponding to all CSG-IDs is sent from the core network to all Home-eNBs. The mobile terminal that has started the home-eNB manual search in ST3105 performs cell search and cell selection in ST3106. In the situation as shown in FIG. 23, when there are a large number of CSG cells belonging to CSG-IDs that the mobile terminal has not registered for user access, the mobile terminal is assigned a CSG-ID that is not registered for user access. In many cases, the CSG cell to which the cell belongs is selected. In the present embodiment, it is possible for the mobile terminal to transmit a request message for an RRC connection to the CSG cell regardless of whether the CSG cell selected by the cell is a CSG cell that has performed user access registration. The mobile terminal also transmits a mobile terminal identification number. The mobile terminal identification number may be included in the RRC connection request message or may be combined with the RRC connection request message.

  Accordingly, in ST3107, the mobile terminal transmits a request for an RRC connection to a CSG cell (here, Home-eNB (A)) that is not a CSG cell (here, Home-eNB (C)) registered for user access. In ST3108, the Home-eNB (A) that has received the RRC connection request checks which CSG-ID the mobile terminal belongs to based on the received mobile terminal identification number. This check is performed using the mobile terminal identification number list belonging to all CSG-IDs transmitted from the core network in ST3104. The Home-eNB (A) searches for and specifies the CSG-ID including the mobile terminal identification number. In ST3109, the Home-eNB (A) notifies the mobile terminal of the white list using the specified CSG-ID. In ST3110, the mobile terminal that has received the whitelist stores the whitelist in its own mobile terminal. The Home-eNB (A) that has notified the mobile terminal of the white list in ST3109 transmits an RRC connection reject message to the mobile terminal in ST3111.

  In ST3104, the core network transmits all CGS-IDs (TAC) and identification information of mobile terminals belonging to the CSG-ID to all CSG cells (here, all Home-eNBs). However, you may transmit the information of the mobile terminal identification number which belongs to each CSG-ID to all HeNBGW. The HeNBGW may transmit information on mobile terminal identification numbers belonging to all CSG-IDs to all CSG cells connected to the own HeNB. Also, all the HeNBGWs receive the RRC connection request from the mobile terminal in ST3107 in the process of transmitting the mobile terminal identification number information belonging to the received all CSG-IDs to all the CSG cells connected to the own HeNB. This may be performed when the received CSG cell sends a message requesting information on mobile terminal identification numbers belonging to all CSG-IDs to the HeNBGW, and the HeNBGW receives the message. By adopting such a method, the white list of the mobile terminal can be transmitted also from the CSG cell belonging to the CSG-ID that the mobile terminal has not registered for user access.

  By adopting the method disclosed in the above description, in addition to the effects described in the fourth to seventh embodiments, it is not necessary to perform transmission / reception of NAS messages such as establishment of an RRC connection or a TAU request. Furthermore, it is possible to improve the use efficiency of radio resources, reduce the signaling load, reduce the control delay of the system, and reduce the power consumption of the mobile terminal.

Embodiment 9 FIG.
In Embodiment 3 to Embodiment 7 described above, the mobile terminal that has registered user access to the CSG cell transmits a TAU request to the core network in order to obtain the white list from the core network. It has been explained that the core network to which the TAU request is transmitted from the mobile terminal checks the CSG-ID (TAC) using the identification number of the mobile terminal and transmits the white list to the mobile terminal. .

  The core network may transmit the white list according to the above method whenever a TAU request message is transmitted from the mobile terminal. However, the TAU request message may occur not only for obtaining the white list from the core network but also for other reasons. For example, when a mobile terminal already has two CSG-IDs in the white list and moves from a CSG cell belonging to one CSG-ID to a CSG cell belonging to another CSG-ID, a new white There is no need to register (update) the list, but since the TACs of the two CSG cells are different, the mobile terminal transmits a TAU request to the core network. In such a case, although it is not necessary for the core network to transmit the white list to the mobile terminal, the white list is transmitted to the mobile terminal, which increases the signaling load unnecessarily. Problems arise.

  Furthermore, in the methods disclosed in the first modification and the seventh embodiment of the sixth embodiment, it is possible for the core network to determine that the mobile terminal is prohibited from establishing an RRC connection or transmitting a TAU request. However, even in this case, the core network should know whether the TAU request message sent by the mobile terminal is for a whitelist request, otherwise it will be sent for other reasons. Since the received TAU request message is also taken into account, the operation becomes inefficient. In order to solve such a problem, the present embodiment discloses that information indicating that a whitelist (registration) update request or a whitelist transmission (notification) request is placed on the TAU request message. .

  For example, in the case of the example shown in FIG. 25 described in the fifth embodiment, the mobile terminal transmits a TAU request to the core network via Home-eNB (A) in ST2507 and ST2508. Information indicating that it is for a whitelist (registration) update request is put on the TAU request message, and the core network is notified that the reason is for a whitelist (registration) update request. To do. With this configuration, the core network can know that the mobile terminal requests whitelist (registration) update. Conversely, if there is no information on the TAU request message indicating that it is for a white list (registration) update request, the TAU request message does not request a white list (registration) update. As a result, it is not necessary to send a white list to the mobile terminal. As a specific method of putting information indicating that it is for a white list (registration) update request on the TAU request message, a white list (registration) update request may be added to the TAU Type information. The Type information may be indicated by a numerical value. In addition, a 1-bit indicator indicating whether or not a whitelist (registration) update request is requested may be provided on the TAU request message.

  By adopting the above-described method, the core network does not need to send a white list to the mobile terminal, but the signaling load increases due to sending the white list to the mobile terminal. Can be suppressed. In addition, when the core network determines to prohibit the mobile terminal from establishing an RRC connection or to transmit a TAU request, the efficiency is low due to considering the TAU request message transmitted for other reasons. It becomes possible to solve the problem of causing the operation.

  Next, a first modification regarding the present embodiment will be described. A method of placing information used for a whitelist (registration) update request on a TAU request message can be applied to the third to seventh embodiments. Here, in order to apply to the method disclosed in the eighth embodiment, information indicating that it is for a whitelist (registration) update request or a whitelist transmission (notification) request is put on the RRC connection request message. Disclose.

  In the eighth embodiment, the white list is transmitted using the RRC connection reject message for the RRC connection request message transmitted by the mobile terminal. It has been explained that the CSG cell to which the RRC connection request is transmitted from the mobile terminal checks the CSG-ID (TAC) using the identification number of the mobile terminal and transmits a white list to the mobile terminal. . The CSG cell may always transmit the white list according to the above method whenever the RRC connection request message is transmitted from the mobile terminal. However, as described above, the CSG cell is useless as described above. There arises a problem that the use efficiency of radio resources is lowered, and further, an inefficient operation is caused. In order to solve such a problem, the first modification discloses disclosing information indicating that it is for a whitelist (registration) update request on the RRC connection request message.

  For example, in the case of the example shown in FIG. 31 described in Embodiment 8, the mobile terminal transmits an RRC connection request to Home-eNB (A) in ST3107. On the RRC connection request message, information indicating that it is for a white list (registration) update request is put, and the reason that the reason is for the white list (registration) update request is indicated together with the RRC connection request. eNB (A) is notified. By doing in this way, Home-eNB (A) can know that the mobile terminal is requesting whitelist (registration) update. Conversely, if the RRC connection request message does not include information indicating that it is for a whitelist (registration) update request, the RRC connection request message requests a whitelist (registration) update. As a result, it is not necessary to send a white list to the mobile terminal.

  As a specific method of putting information indicating that it is for a white list (registration) update request on the RRC connection request message, as a cause information of the RRC connection request message, a white list (registration) update request Should be added. The reason information may be indicated by a numerical value. Further, a 1-bit indicator indicating whether or not a whitelist (registration) update request is requested may be provided on the RRC connection request message. Although this modification has been described for the case where it is applied to the method disclosed in the eighth embodiment, it can also be applied to the third to seventh embodiments. The present invention can be applied when an RRC connection is requested when a whitelist (registration) update request is made.

  By adopting the method disclosed in the present embodiment, in addition to the effects described in the eighth embodiment, it is not necessary for the CSG cell to transmit a whitelist to the mobile terminal as described above. Regardless of this, a whitelist registration (update) notification message is transmitted to the mobile terminal, and there is a problem that radio resources are unnecessarily reduced, and further, the CSG cell issues an RRC connection request to the mobile terminal. When it is determined that transmission is prohibited, it is possible to solve the problem of causing an inefficient operation due to the consideration of the RRC connection request message transmitted for other reasons. Also, by putting information indicating that it is for the whitelist (registration) update request on the TAU request message or RRC connection request message, RRC to the CSG cell that is not the CSG cell that the mobile terminal has registered for user access. The establishment of a connection and transmission of a TAU request message to the core network via the CSG cell are not limited to when manual search is activated. By applying the method shown in the present embodiment and the modification, if the mobile terminal is for a whitelist (registration) update request, the mobile terminal is sent to a CSG cell that is not a CSG cell that has been registered for user access. It is only necessary to allow establishment of an RRC connection and transmission of a TAU request message to the core network via the CSG cell. For example, after user access registration, automatic search is not started after manual registration. It is also possible to perform communication for obtaining a white list automatically, and periodically (for example, periodically at a predetermined period until a white list is obtained without starting a manual search). It is also possible to communicate for obtaining a white list. In this way, the procedure until the mobile terminal obtains the registered (updated) whitelist can be made flexible, and many future CSG cells will be installed and user access registration will be performed in various places. It is possible to cope with such a situation. In addition, by applying the method shown in the present embodiment and the modified example, information indicating that the mobile terminal has started manual search as disclosed in the fourth and fifth embodiments is displayed as an RRC connection request, It is not necessary to include the TAU request, and the amount of signaling can be reduced.

Embodiment 10 FIG.
In Embodiments 4 to 7, the mobile terminal that has registered user access to the CSG cell transmits a TAU request to the core network via the CSG cell in order to obtain the white list from the core network (CN). It will be. The core network that has transmitted the TAU request from the mobile terminal checks the CSG-ID (TAC) using the identification number of the mobile terminal, and determines that access to the CSG cell is impossible. It has been described that a TAU reject message is transmitted to the mobile terminal via the CSG cell. On the other hand, the method for determining the next operation according to the TAU reject message received by the mobile terminal from the core network via the CSG cell has also been described. In such a case, the mobile terminal should know whether or not the TAU reject message received via the CSG cell was for a TAU request for a whitelist registration (update) request. In this case, the TAU reject message transmitted for other reasons is also taken into account, which causes an inefficient operation.

  On the other hand, in 3GPP, consideration is given to putting reason information of “no suitable cells” in a TAU reject message or an RRC connection reject message. However, as described above, since there are many types of “suitable cell” definitions, it is not possible to specify which definition does not apply. In order to solve such a problem, in the present embodiment, the TAU reject message indicates that the reason for the rejection is that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs. Disclose information.

  For example, in the case of the example shown in FIG. 27 described in Embodiment 6, the core network transmits a TAU request reject message to the mobile terminal via Home-eNB (A) in ST2710 and ST2711. On the TAU reject message, by putting information indicating that the reason for the rejection is that the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the reason is as follows. The CSG-ID to which the Home-eNB (A) belongs is notified that the mobile terminal identification number is not registered. In this way, the mobile terminal can know that the reason for the received TAU request reject message is that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs. Become. Conversely, if the TAU reject message does not contain information indicating that the reason for the rejection is that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs, the TAU reject You can see that the message is for some other reason.

  As a specific method of putting information indicating that the reason for rejection on the TAU reject message is that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs, the TAU reject message Information indicating that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs may be added to the cause information. The reason information may be indicated by a numerical value. Further, a 1-bit indicator indicating whether or not the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs may be provided on the TAU request reject message.

  By using the method disclosed in the present embodiment, in addition to the effects described in the fourth to seventh embodiments, the RRC is further applied to the TAU reject message transmitted from the core network by the mobile terminal as described above. To solve the problem of inefficient operation caused by considering TAU reject messages sent for other reasons when it is determined that connection establishment or TAU request transmission is prohibited. It becomes possible.

  Next, a first modification of the tenth embodiment described above will be described. Here, in order to apply to the method disclosed in Embodiment 8, information indicating that the reason for the rejection is not registered in the CSG-ID to which the CSG cell belongs is included in the RRC connection reject message. Disclose that. In the eighth embodiment, it has been described that the mobile terminal performs the process of prohibiting the transmission of the RRC connection request message using the RRC connection reject message for the RRC connection request message transmitted by the mobile terminal. When a mobile terminal transmits an RRC connection reject message from a CSG cell, the mobile terminal may be allowed to prohibit transmission of an RRC connection request message to the CSG cell. Similarly, it will cause inefficient operation.

  In order to solve such a problem, in the first modification, the reason for the rejection is indicated on the RRC connection reject message because the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs. Disclose information. For example, in the case of the example shown in FIG. 31 described in the eighth embodiment, the mobile terminal receives an RRC connection reject from Home-eNB (A) in ST3110. Home-eNB (A) is information indicating that the reason for the rejection is because the mobile terminal identification number is not registered in the CSG-ID to which Home-eNB (A) belongs on the RRC connection reject message. And the mobile terminal is notified that the reason for the rejection is that the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs. In this way, the mobile terminal can know that the received RRC connection reject message is because the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs. . Conversely, if the RRC connection reject message does not contain information indicating that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs, the reject is performed. It is possible to know that this is not because the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs.

  As a specific method of putting information indicating that the reason for rejection on the RRC connection reject message is that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs, RRC connection reject Information indicating that the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs may be added to the message cause information. The reason information may be indicated by a numerical value. Further, a 1-bit indicator indicating whether or not the mobile terminal identification number is not registered in the CSG-ID to which the CSG cell belongs may be provided on the RRC connection reject message.

  By adopting the method disclosed in the present embodiment, in addition to the effects described in the eighth embodiment, when the mobile terminal receives an RRC connection reject message from the CSG cell as described above, an RRC connection request is made. In the case of the method of determining prohibition of the above, it is possible to solve the problem of causing an inefficient operation due to the consideration of the RRC connection reject message transmitted for other reasons.

Embodiment 11 FIG.
A description was added that when a whitelist is registered or changed, the mobile terminal may erroneously receive the whitelist content sent from the core network. In such a case, in a situation where there are a large number of CSG cells, there is a case where a CSG cell belonging to the CSG-ID of the white list received in error is selected, and the mobile terminal receives the CSG- An RRC connection is established many times to the CSG cell belonging to the ID, and a TAU request is repeated to the core network via the CSG cell. Therefore, there arises a problem that the use efficiency of radio resources and the extreme decrease in signaling efficiency are caused as a system. Furthermore, it takes a lot of time from the cell search to the standby operation, which causes a problem that a large control delay occurs in the system and a problem that the power consumption becomes enormous in the mobile terminal.

  In order to solve these problems, this embodiment discloses a method in which the mobile terminal explicitly transmits success / failure (Ack / Nack) of whitelist reception to the core network. FIG. 32 shows a sequence diagram of a method of explicitly transmitting success / failure (Ack / Nack, complete / incomplete, complete / incomplete) of white list reception at the mobile terminal to the core network at the time of whitelist registration. The figure shows the case of an LTE communication system using, for example, a Home-eNB. The figure will be described. Here, the mobile terminal performs user access registration with the Home-eNB (C), but the operation from ST3201 to ST3203 is the same as described above, and thus the description is omitted. A mobile terminal that has started manual search for a CSG cell (here, Home-eNB) in ST3204 performs cell search and cell selection in ST3205. In the situation as shown in FIG. 23, when there are a larger number of CSG cells belonging to CSG-IDs that the mobile terminal has not registered for user access, the mobile terminal selects a CSG cell. As disclosed in the fourth embodiment, whether the CSG cell selected by the cell is a CSG cell that has performed user access registration, the mobile terminal can establish an RRC connection to the CSG cell, and TAU can be transmitted to the network via the network. Accordingly, in ST3206, the mobile terminal transmits a request for an RRC connection to a CSG cell (here Home-eNB (A)) that is not a CSG cell (here Home-eNB (C)) registered for user access. The Home-eNB (A) that has received the establishment request for the RRC connection establishes an RRC connection between the mobile terminal and the Home-eNB (A) by transmitting an establishment permission for the establishment request to the mobile terminal.

  Next, in ST3207 and ST3208, the mobile terminal transmits a TAU request message to the core network via the Home-eNB (A). Here, the mobile terminal also transmits the mobile terminal identification number. The mobile terminal identification number may be included in the TAU request message, may be combined with the TAU request message, or may be transmitted as a separate message. The core network that has received the TAU request message checks whether or not the mobile terminal belongs to the CSG-ID of the Home-eNB (A) based on the received mobile terminal identification number. The method described in ST2207 disclosed in FIG. 22 can be applied to this check method. Since the mobile terminal identification number is not registered in the CSG-ID to which the Home-eNB (A) belongs, the core network determines that the mobile terminal cannot access the Home-eNB (A). In the present embodiment, for example, the method disclosed in the fifth embodiment is used. Even if it is determined that the mobile terminal cannot access the Home-eNB (A), the core network transmits a whitelist of the mobile terminal to the Home-eNB (A) in ST3210 before transmitting the TAU reject. Send. In ST3211, the Home-eNB (A) that has received the whitelist of the mobile terminal transmits the whitelist to the mobile terminal.

  Here, the mobile terminal that has received the white list transmits Ack indicating that the white list has been successfully received to Home-eNB (A) in ST3212. This Ack may be a NAS message. In Step ST3213, the Home-eNB (A) that has received the Ack indicating that the whitelist is successfully received from the mobile terminal transmits the Ack indicating that the whitelist has been successfully received to the core network. Information for notifying that the mobile terminal has completed user access registration to the Home-eNB (C) that the mobile terminal has registered for user access in ST3215, in the core network that has received Ack of successful whitelist reception. Send. On the other hand, in ST3214, the mobile terminal stores the received white list in its own mobile terminal. In ST3216 and ST3217, the core network that has received Ack that has successfully received the whitelist in ST3213 transmits a TAU reject message for the TAU request to the mobile terminal via Home-eNB (A). The mobile terminal that has received the TAU reject message releases the RRC connection with the Home-eNB (A) in ST3218.

  The mobile terminal that has failed to receive the white list in ST 3211 transmits Nack of white list reception failure to the Home-eNB (A) in ST 3212. This Nack may be a NAS message. In Step ST3213, the Home-eNB (A) that has received the white list reception failure Nack from the mobile terminal transmits the white list reception failure Nack to the core network. The core network that has received the white list reception failure Nack transmits the white list to the mobile terminal via the Home-eNB (A) again in ST3210 and ST3211. Such processing is repeated until the mobile terminal has successfully received the white list. If the mobile terminal has successfully received, ST3212 and subsequent processes are performed. By adopting such a method, it is possible to greatly reduce the probability that the mobile terminal erroneously receives the white list contents transmitted from the core network. Therefore, in a situation where there are a large number of CSG cells as described above, the mobile terminal selects a CSG cell belonging to the CSG-ID of the whitelist received in error, and repeatedly RRCs the CSG cell. Problems such as establishment of a connection and repeated TAU requests to the core network via the CSG cell can be solved. By eliminating these problems, it is possible to eliminate an extreme decrease in radio resource usage efficiency and signaling efficiency in future system operation.

  In the fourth to eleventh embodiments of the present invention, white list registration has been described. However, the present invention is applicable not only to white list registration but also to white list updating (including deletion and addition). In the examples of Embodiments 1 to 11 in the present invention, the communication system using the LTE scheme in which Home-eNB is used as the CSG cell has been described. Applicable. In the case of a UMTS communication system in which Home-NB is used as a CSG cell, an RNC is provided between a base station (Home-NB, NB) and a core network, and an RRC message such as an RRC connection request is transmitted between the mobile terminal and the RNC. NAS messages such as TAU requests may be transmitted and received from the mobile terminal to the core network via the base stations (Home-NB, NB) and RNC. By doing so, the present invention can be applied to a UMTS communication system in which Home-NB is used as a CSG cell.

Embodiment 12 FIG.
Non-Patent Document 6 discloses an RRC connection re-establishment (RRC (Radio Resource Control) connection re-establishment) procedure as an LTE mobile communication system. The flow of the process as the mobile terminal concerning the RRC connection re-establishment disclosed in FIG. 33 is shown. In step ST3301, the mobile terminal determines whether or not a radio link failure has been detected. As a result, if a radio link failure is detected, the process proceeds to step ST3305. If not detected, the process proceeds to step ST3302. In Step ST3302, the mobile terminal determines whether a handover failure has occurred. As a result, when handover fails, the process proceeds to step ST3305, and when not failed, the process proceeds to step ST3303. In Step ST3303, the mobile terminal determines whether there is an instruction from a layer having a lower integrity failure. As a result, if there is an instruction for integrity failure, the process proceeds to step ST3305, and if there is no instruction, the process proceeds to step ST3304. In Step ST3304, the mobile terminal determines whether or not RRC connection reconfiguration failure has occurred. As a result, when the RRC connection reconfiguration has failed, the process proceeds to step ST3305, and when it has not failed, the process proceeds to step ST3301. The mobile terminal that has returned to Step ST3301 repeats the processes of Step ST3301, Step ST3302, Step ST3303, and Step ST3304. Further, the order of processing in step ST3301, step ST3302, step ST3303, and step ST3304 is arbitrary, and may be simultaneous.

  The radio link failure in which the mobile terminal determines whether or not there is detection in step ST3301 will be described below. For example, T310 is a time during which radio link recovery is allowed after a physical layer problem is detected. Instead of T310, it is also possible to define a counter value of a physical layer failure from when a physical layer problem is detected until wireless link recovery is permitted. Also, the time allowed for wireless link recovery after receiving the random access problem indicator from the MAC is, for example, T312.

  When the timer (T310, T312) expires, the mobile terminal detects a radio link failure. The timers (T310, T312) are transmitted from the base station (network side) to the mobile terminal as a part of the mobile terminal timer and constant information element (UE-Timer And Constansts information element). Information BlockType2: SIB2), which is reported on PDSCH (DL-SCH) using BCCH.

  The handover failure determined by the mobile terminal in step ST3302 will be described below. The mobile terminal executes handover by receiving an RRC message that triggers handover. When the mobility control information (Mobility Control information) is included in the RRC connection reconfiguration message, the mobile terminal sets a timer (for example, T304) included in the mobility control information. When the MAC completes the random access procedure, the mobile terminal stops the timer (T304). When the timer (T304) expires, the mobile terminal determines that the handover has failed. That is, the timer (T304) defines an allowable time required for the MAC to complete the random access procedure after the execution of the handover is started. The timer (T304) is mapped to the RRC connection reconfiguration message as a part of the mobility control information element by the base station (network side) to the mobile terminal. And NAS individual information (NAS (Non Access Stratum) Dedicated information).

  The RRC connection reconfiguration failure determined by the mobile terminal in step ST3304 will be described below. When the configuration incapable of the UE is included in the RRC connection reconfiguration message, it is determined that the RRC connection reconfiguration has failed. The base station (network side) notifies the RRC connection reconfiguration message to the mobile terminal as NAS individual information. In step ST3305, after detecting the physical layer problem, the mobile terminal stops the timer for the time (T310) during which radio link recovery is allowed, and moves to step ST3306. In Step ST3306, after receiving the random access problem indicator from the MAC, the mobile terminal stops the timer (T312) for allowing radio link recovery, and moves to Step ST3307. In Step ST3307, the mobile terminal allows detection of a radio link failure, determination of handover failure, determination of integrity failure, or determination of RRC connection reconfiguration failure until the selection of a cell in E-UTRA. A time timer (for example, T311) is started, and the process proceeds to step ST3308. The timer (T311) is transmitted from the base station (network side) to the mobile terminal as a part of the mobile terminal timer and constant information element (UE-Timer And Constansts information element). : SIB2) and notified by PDSCH using BCCH. In Step ST3308, the mobile terminal resets MAC (Media Access Control) and moves to Step ST3309. In Step ST3309, the mobile terminal resets RLC (Radio Link Control) of all the set radio bearers (Radio Bearer: RB), and moves to Step ST3310.

  In step ST3310, the mobile terminal determines whether the T311 timer has expired. As a result, if the timer has expired (timeout, timer completed, timer expired), the process proceeds to step ST3311, and if not expired, the process proceeds to step ST3314. In Step ST3311, the mobile terminal resets RLC reconfiguration of all radio bearers set as MAC, and moves to Step ST3312. In Step ST3312, the mobile terminal releases all radio resources and moves to Step ST3313. In Step ST3313, the mobile terminal transits to the RRC_IDLE state. In Step ST3314, the mobile terminal determines whether an E-UTRA cell has been selected by a cell selection procedure (cell selection process) or a cell reselection procedure (cell reselection process). As a result, when an E-UTRA cell is selected, the process proceeds to step ST3315, and when no E-UTRA cell is selected, the process proceeds to step ST3317. A mobile terminal stops timer T311 in step ST3315, and transfers to step ST3316. In Step ST3316, the mobile terminal transmits an RRC connection reestablishment request message to the network side. In Step ST3317, the mobile terminal determines whether or not a different radio access technology cell (inter-RAT (Radio Access Technology Cell)) is selected by the cell selection procedure. If the inter-RAT cell is not selected, the process proceeds to step ST3310. The mobile terminal that has returned to step ST3310 repeats the processes of step ST3310, step ST3314, and step ST3317.

  The problem in the twelfth embodiment will be described below. As described above, CSG cells are introduced in LTE and UMTS. However, the procedure as a mobile communication system for re-establishing RRC connection in Non-Patent Document 6 does not disclose how to introduce a CSG cell. Moreover, there is no suggestion about the problem pointed out in the twelfth embodiment. In order to receive a normal service in a CSG cell, the mobile terminal needs to be registered in the CSG cell. After completing the registration, the mobile terminal stores the CSG-ID of the CSG cell registered in the white list existing in the mobile terminal (USIM, SIM, memory, CPU, etc.). The CSG cell broadcasts a CSG-ID or a tracking area code (TAC) associated with the CSG-ID to the mobile terminals being served as system information. CSG-ID or TAC is mapped to System Information Block Type 1 (System Information Block Type 1: SIB1), and is broadcast from the CSG cell on PDSCH using BCCH. Note that the period for notifying SIB1 is once every 20 ms. Compared to the case where the UE selects a CSG cell as a suitable cell and performs location registration or standby in order to obtain a normal service, as compared to selecting a non-CSG cell as a suitable cell. Therefore, it is necessary to additionally perform processing for determining whether or not the mobile terminal is registered in the CSG cell. In order to determine whether or not the mobile terminal is registered in the CSG cell, the CSG-ID (or TAC) broadcast by the CSG cell and the CSG-ID in the white list in the mobile terminal are the same. It is necessary to judge.

  An RRC connection re-establishment procedure when a CSG cell is introduced is shown. The procedure is almost the same as in FIG. 33, but details of the characteristic step ST3314 are shown in FIG. In step ST3401, the mobile terminal determines whether the white list includes the CSG-ID. Alternatively, the mobile terminal determines whether it is registered in the CSG cell. When CSG-ID is included in the white list or when it is registered in the CSG cell, the mobile terminal makes a transition to step ST3402. When CSG-ID is not included in the white list, or when the white list is not registered in the CSG cell, the mobile terminal makes a transition to step ST3410. In Step ST3402, the mobile terminal determines whether there is a cell that can serve as a serving cell in the CSG cell based on the measurement result of the reception quality of the neighboring cell (Neighboring Cell). When it exists, it transfers to step ST3403. When it does not exist, it transfers to step ST3410. In Step ST3403, the mobile terminal selects the best cell (also referred to as the best cell) based on the reception quality among the cells that can be serving cells in the CSG cell from the measurement results of the reception quality of the neighboring cells, The process proceeds to step ST3404.

  In Step ST3404, the mobile terminal receives the physical downlink control channel (also referred to as PDCCH, L1 / L2 signaling channel) of the cell selected in Step ST3403. In receiving the PDCCH, the mobile terminal needs to perform a blind detection process. As a result of the blind detection, BCCH allocation on PDSCH is received, and the process proceeds to step ST3405. In Step ST3405, the mobile terminal receives the PDSCH according to the BCCH assignment received in Step ST3404, and moves to Step ST3406. In PDSCH, BCCH to which SIB1 is mapped is transmitted once every 20 ms. A mobile terminal acquires SIB1 in step ST3405. In Step ST3406, the mobile terminal obtains the CSG-ID or TAC mapped to the SIB1 received in Step ST3405, and moves to Step ST3407. Although there is a possibility that the CSG-ID is mapped to system information different from SIB1, even in this case, the present embodiment can be applied.

  In Step ST3407, the mobile terminal determines whether the CSG-ID of the CSG cell obtained in Step ST3406 and the CSG-ID of the registered CSG cell stored in the white list of the mobile terminal are the same. . As a result, the mobile terminal determines whether or not the CSG cell can be a “suitable cell”. That is, when the CSG-ID of the CSG cell exists in the white list, the cell can be a “suitable cell” as a registered CSG cell. On the other hand, if the CSG-ID of the CSG cell does not exist in the white list, the cell cannot be a “suitable cell” as an unregistered CSG cell. When the said CSG cell is a registered CSG cell, it transfers to step ST3315 of FIG. When the said CSG cell is a CSG cell which is not registered, it transfers to step ST3408.

  In Step ST3408, the mobile terminal omits the CSG cell from the E-UTRA cell selection process, and moves to Step ST3409. In step ST3409, the mobile terminal determines whether the T311 timer has expired. As a result, if the timer has expired (timeout, timer completed, timer expired), the process proceeds to step ST3311 in FIG. 33, and if not completed, the process returns to step ST3402. In Step ST3410, the mobile terminal determines whether there is a cell that can serve as a serving cell in the non-CSG cell based on the measurement result of the reception quality of the neighboring cell (Neighboring Cell). When it exists, it transfers to step ST3411. If it does not exist, the process proceeds to step ST3317 in FIG. In Step ST3411, the mobile terminal selects the best cell based on the reception quality among the cells that can be serving cells in the non-CSG cell from the measurement results of the reception quality of the neighboring cells, and moves to Step ST3315 in FIG. To do.

  As is clear from the above and FIG. 34, the time required for E-UTRA cell selection by a mobile terminal including a CSG-ID in the white list, that is, a mobile terminal registered in any one CSG cell, is CSG-ID in the white list. It can be seen that there is a possibility that the time required for E-UTRA cell selection may be longer for a mobile terminal that does not include the mobile terminal, that is, a mobile terminal that is not registered in any CSG cell. This phenomenon appears more conspicuously than when the mobile terminal has registered in the CSG cell (assuming CSG-ID = 10), but the CSG cell (CSG-ID = 10) does not exist in the vicinity. In this case, the mobile terminal determines “unregistered CSG cell” in step ST3407 of FIG. Furthermore, when the mobile terminal exists in a place where there are many CSG cells not registered by the own mobile terminal, and the reception quality of many CSG cells not registered is good and the cell can be a serving cell, Appears more prominently. This is because the process from step ST3402 to step ST3409 in FIG. 34 is repeated until there is no cell that can serve as a serving cell in the CSG cell.

  The following problems arise from the difference in time required for cell selection between a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list. As described above, the allowable time from selection of a cell in E-UTRA from detection of radio link failure, determination of handover failure, determination of integrity failure, or determination of RRC connection reconfiguration failure Timers (eg, T311). In the case where there is one kind of timer as described above, a case is considered where the timer value is adapted to a mobile terminal having a CSG-ID in the white list. In that case, since the CSG-ID is not included in the white list, the timer does not time out even though the time required for cell selection is relatively short. That is, in step ST3310 of FIG. 33, the determination that “timer is ended” is delayed unnecessarily. This means that the release of all radio resources (radio resources) performed in step ST3312 of FIG. 33 is delayed unnecessarily. Therefore, there arises a problem of securing unnecessary radio resources. Conversely, consider a case where the timer value is adapted to a mobile terminal that does not have a CSG-ID in the white list. In this case, since the time required for cell selection is long because the CSG-ID is included in the white list, the timer is used even though there is still a cell that can be a serving cell in the CSG cell, for example, during cell selection. May time out.

  That is, it can be considered that the determination of “timer expired” in step ST3310 in FIG. 33 or “timer expired” in step ST3409 in FIG. 34 is too early. This means that although the MAC of a mobile terminal having a CSG-ID in the white list has been reset, there is a problem of reducing the possibility of re-establishing an RRC connection in a state where a radio bearer, that is, a radio resource is secured. This causes a problem that a mobile terminal having a CSG-ID in the white list makes a transition to the RRC_IDLE state and a control delay occurs even though a cell with good reception quality exists in the vicinity. Non-Patent Document 6 does not suggest this problem. Further, FIG. 34 shows a case where the selection is performed with higher priority than the selection of the CSG cell than the selection of the non-CSG cell. However, the above problem occurs even if this priority is not provided. Furthermore, this problem occurs both when introducing a CSG cell into an LTE (E-UTRAN) system and when introducing a CSG cell into a W-CDMA (UTRAN, UMTS) system.

  A solution to the problem of the twelfth embodiment is shown below. This solution is applicable to both LTE and W-CDMA systems. In the twelfth embodiment, in order to solve the above-described problem, it is disclosed that a different timer is separately provided depending on whether or not the whitelist has a CSG-ID and reflected in the mobile terminal. More specifically, E is determined based on whether a radio link failure is detected based on whether or not the whitelist has a CSG-ID, whether it is a handover failure, an integrity failure, or an RRC connection reconfiguration failure. -It is disclosed that a timer (for example, T311) of an allowable time until a cell in UTRA is selected is provided separately (for example, with T311_whitelist and without T311_whitelist) and reflected on the mobile terminal.

  A specific operation example will be described with reference to FIG. In FIG. 35, the description of the same step number as in FIG. 33 is omitted. Note that FIG. 34 can also be used in FIG. In Step ST3501, the mobile terminal determines whether or not the white list includes the CSG-ID. Alternatively, the mobile terminal determines whether it is registered in the CSG cell. When CSG-ID is included in the white list or when it is registered in the CSG cell, the mobile terminal makes a transition to step ST3502. If the CSG-ID is not included in the white list, or if it is not registered in the CSG cell, the mobile terminal moves to step ST3503. In step ST3502, the mobile terminal accepts until detection of a radio link failure, determination of handover failure, determination of integrity failure, or determination of RRC connection reconfiguration failure to select a cell in E-UTRA. Detection of radio link failure, determination of handover failure, or determination of integrity failure when the time timer (for example, T311) includes CSG-ID in the white list or registered in the CSG cell Alternatively, a timer (for example, having T311_whitelist) for an allowable time from determination of failure of RRC connection reconfiguration to selection of a cell in E-UTRA is set, and the process proceeds to step ST3307.

  In Step ST3503, the mobile terminal allows detection of a radio link failure, determination of handover failure, determination of integrity failure, or determination of RRC connection reconfiguration failure until the selection of a cell in E-UTRA. Detection of radio link failure, determination of handover failure, or determination of integrity failure when the time timer (for example, T311) does not include the CSG-ID in the white list or is not registered in the CSG cell Alternatively, a timer (for example, no T311_white list) of an allowable time from the determination that the RRC connection reconfiguration has failed to the selection of a cell in E-UTRA is set, and the process proceeds to step ST3307.

  Next, a timer notification method in which different timers are separately provided depending on whether or not the whitelist has a CSG-ID will be disclosed. As a first method, a timer used when the white list has a CSG-ID (for example, T311_white list), and a timer used when the white list does not have a CSG-ID (for example, T311_white list not) In both cases, the serving cell (network side) notifies the mobile terminal. More specifically, notification is performed using a dedicated control channel (DCCH) or a broadcast control channel (BCCH). When using an individual control channel, it is an excellent method in that control according to the communication state of the mobile terminal is possible. In addition, when BCCH is used, it is possible to notify all mobile terminals being served thereby, which is an excellent method in terms of effective use of radio resources. As a specific example of notification using BCCH, mapping to MIB or SIB can be considered. When the MIB is used, the MIB is mapped to the PBCH, which is an excellent method in that the mobile terminal can receive with a small control delay. When using SIB, it notifies using SIB1. MIB or SIB1 is an excellent method in that the control delay of the mobile terminal is reduced in that it is the broadcast information received at the minimum necessary for the operation waiting from the cell search. Also, as part of the mobile terminal timer and constant information element (UE-Timer And Constansts information element), it is mapped to System Information Block Type 2 (System Information Block Type2: SIB2) and notified on PDSCH using BCCH. . Furthermore, regardless of whether the serving cell is a CSG cell or a non-CSG cell, a timer used when the whitelist has a CSG-ID (eg, T311_whitelist), and when the whitelist does not have a CSG-ID Both the timer to be used (for example, T311_no white list) is sent from the serving cell (network side) to the mobile terminal as a part of the mobile terminal timer and constant information element (UE-Timer and Constants information element). BlockType2: SIB2) and is notified by PDSCH using BCCH. When SIB2 is used, it is an excellent method in that it can be notified simultaneously with the same (same type) parameters from the viewpoint of a timer, and processing of the received mobile terminal is easy. Furthermore, even if a method of notifying with system information other than SIB1 and SIB2 is broadcast information, it can be notified to all mobile terminals being served thereby, which is an excellent method in terms of effective use of radio resources. In the first method, since the mobile terminal can obtain a different timer only by receiving the BCCH or DCCH of the serving cell, the effect of preventing control delay can be obtained.

  As a second method, a timer used when the whitelist does not have a CSG-ID (for example, T311_no whitelist) is used when the serving cell (network side) sends a mobile terminal timer and a constant information element ( As part of the UE-Timer and Constansts information element), it is mapped to the system information block type 2 and notified on PDSCH using BCCH. Furthermore, regardless of whether the serving cell is a CSG cell or a non-CSG cell, the serving cell (network side) uses a timer (for example, no T311_white list) used when the whitelist does not have a CSG-ID in the mobile terminal. As part of the timer and constant information elements, it is mapped to the system information block type 2 and notified on the PDSCH using BCCH. A timer (for example, with T311_whitelist) used when the whitelist has a CSG-ID is mapped to system information by the CSG cell to the mobile terminal, and is notified by PDSCH using BCCH.

  A specific operation example will be described with reference to FIGS. 36, the description of the same step numbers as those in FIGS. 33 and 35 is omitted. In Step ST3601 of FIG. 36, the mobile terminal determines whether the serving cell is a CSG cell. When a serving cell is a CSG cell, it transfers to step ST3502. When a serving cell is not a CSG cell, it transfers to step ST3503. In Step ST3502 of FIG. 36, the mobile terminal sets T311_white list presence (T311 received from the CSG cell (serving cell)) to T311. In Step ST3503 of FIG. 36, the mobile terminal sets T311_No whitelist (T311 received from the non-CSG cell (serving cell)) to T311. In step ST3701 of FIG. 37, the mobile terminal determines whether or not a timer (for example, T311_white list exists) used when T311 has a CSG-ID in the white list is set. When T311_white list presence is set, the mobile terminal makes a transition to step ST3407. When T311_white list presence is not set, the mobile terminal makes a transition to step ST3702.

  In Step ST3702 of FIG. 37, the mobile terminal obtains T311_whitelist presence from the system information mapped to the BCCH on the PDSCH received in Step ST3405, and moves to Step ST3703. In Step ST3703 of FIG. 37, the mobile terminal selects a cell in the E-UTRA from detection of a radio link failure, determination of handover failure, determination of integrity failure, or determination of RRC connection reconfiguration failure. Detection of a radio link failure, determination of handover failure, or integrity failure when a CSG-ID is included in the white list in a timer (eg, T311) of an allowable time until it is registered or registered in a CSG cell Or a timer (for example, with T311_whitelist) of an allowable time from the determination of RRC connection reconfiguration failure to the selection of a cell in E-UTRA is set, and the process proceeds to step ST3407. According to the second method, it is possible to obtain an effect that the system information of the non-CSG cell does not need to be changed due to the introduction of CSG. This eliminates the need for a change in an LTE system (eUTRA / eUTRAN) that does not include an existing CSG, and improves compatibility. In the second method, the method of notifying a timer (for example, T311_white list) used when the white list has a CSG-ID in the system information mapped to the BCCH on the PDSCH has been specifically described. Also in the case of the second notification method, a specific example can use the dedicated control channel and the broadcast control channel (MIB, SIB) as in the first notification method.

  The effects of the twelfth embodiment are shown below. There is a possibility that a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list exist together under the base station. Detecting radio link failure separately for a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list, or determining a handover failure, or determining an integrity failure, Alternatively, it is possible to set a timer (for example, T311) of an allowable time from determination of RRC connection reconfiguration failure to selection of a cell in E-UTRA. This makes it possible to appropriately set the timer value for a mobile terminal having a CSG-ID in the white list and for a mobile terminal having no CSG-ID in the white list. Therefore, it is possible to avoid securing unnecessary radio resources due to the setting of the timer for a long time, and the effect of effective use of radio resources can be obtained. Moreover, the effect that the increase in the control delay as a mobile communication system by the said timer being set short can be acquired. Prevention of control delay can also be achieved with the effect of reducing power consumption of the mobile terminal.

  The solution of the twelfth embodiment is excellent in that the network side (base station or the like) has the above effect without knowing whether the corresponding mobile terminal has a CSG-ID in the white list. . Thereby, it is not necessary to notify the presence / absence of the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load on the base station in that the base station does not need to manage the presence / absence of CSG-ID in the white list of the mobile terminal being served.

Embodiment 13 FIG.
Non-Patent Document 7 discloses that priorities of different E-UTARAN frequencies or Inter-RAT frequencies in LTE mobile communication systems are provided from the network side to the UE by system information and RRC messages. ing. When priority is assigned from the network side to the mobile terminal via dedicated signaling, the mobile terminal ignores all priorities provided by the system information. Non-Patent Document 6 describes the following. The idle mode mobility control information (idlemode Mobility Control Info) is included in the RRC connection release message, and the cell reselection priority expiry timer is included in the idle mode mobility control information. When (for example, T320) is included, the following operation is performed as the mobile communication system. The flow of processing as a mobile terminal disclosed in FIG. 38 is shown. In Step ST3801, the mobile terminal receives the priority of different E-UTRAN frequencies or Inter-RAT frequencies in the system information transmitted from the base station, and moves to Step ST3802. In step ST3802, the mobile terminal determines whether a different E-UTRAN frequency or Inter-RAT frequency priority is received in the individual signal transmitted from the base station. If received, the mobile terminal makes a transition to step ST3803. When not receiving, it transfers to step ST3804. In Step ST3803, the mobile terminal performs reselection of cells according to the priority order received in the system information.

  In Step ST3804, the mobile terminal performs reselection of the cell according to the priority received by the individual signal, and moves to Step ST3805. In Step ST3805, the mobile terminal determines whether or not it has left the PLMN for which priority is set by an individual signal. When it leaves | separates, it transfers to step ST3808. When not away, it transfers to step ST3806. A mobile terminal judges whether it changed to the RRC connection state in step ST3806. If a transition is made, the mobile terminal makes a transition to step ST3808. When not changing, it transfers to step ST3807. In Step ST3807, the mobile terminal determines whether or not the timer T320 has expired. If completed, the process proceeds to step 3808. When not complete | finished, it returns to step ST3804 and repeats the process of step ST3804 to step ST3807. Further, the order of processing from step ST3804 to step ST3807 is arbitrary, and may be simultaneous.

  The problem in the thirteenth embodiment will be described below. As described above, CSG cells are introduced in LTE and UMTS. A user equipment that is not registered in any CSG cell, that is, a user equipment that does not have a CSG-ID in the white list, uses only non-CSG cells as a target for cell reselection. A user equipment registered in any CSG cell, that is, a user equipment having a CSG-ID in the white list, reselects not only the non-CSG cell but also the CSG cell. Furthermore, studies on frequencies dedicated to CSG (frequency layer) in which only CSG cells exist are also in progress. Therefore, a mobile terminal that is not registered in the CSG cell (a mobile terminal that does not have a CSG-ID in the white list) and a mobile terminal that is registered in any CSG cell (a mobile terminal that has a CSG-ID in the white list) When the same priority order (different E-UTRAN frequency or Inter-RAT frequency priority order) is set for the mobile communication system, problems such as an increase in control delay occur. Furthermore, this problem occurs both when introducing a CSG cell into an LTE (E-UTRAN) system and when introducing a CSG cell into a W-CDMA (UTRAN, UMTS) system.

  A solution to the problem of the thirteenth embodiment is shown below. This solution is applicable to both LTE and W-CDMA systems. In the thirteenth embodiment, different priorities (different E-UTARAN frequencies, Inter-RAT frequency priorities, etc.) are separately provided depending on whether or not the whitelist has a CSG-ID in order to solve the above-described problem. To be reflected in the mobile terminal. A specific operation example will be described with reference to FIG. In FIG. 39, the description of the same step number as in FIG. 38 is omitted. In Step ST3901, the mobile terminal uses the priority (different E-UTRAN frequencies) for the mobile terminal (for the mobile terminal registered in the CSG cell) having the CSG-ID in the white list transmitted from the base station in the system information. Alternatively, the priority order of the Inter-RAT frequency) and the priority order for a mobile terminal that does not have a CSG-ID in the white list (for a mobile terminal not registered in the CSG cell) are received, and the process proceeds to Step ST3802. In Step ST3902, the mobile terminal determines whether the white list includes the CSG-ID. Alternatively, the mobile terminal determines whether it is registered in the CSG cell. When CSG-ID is included in the white list or when it is registered in the CSG cell, the mobile terminal makes a transition to step ST3903. When CSG-ID is not included in the white list or when the white list is not registered in the CSG cell, the mobile terminal makes a transition to step ST3904. In Step ST3903, the mobile terminal performs reselection of the cell according to the priority order for the mobile terminal (for the mobile terminal registered in the CSG cell) having the CSG-ID in the white list received in the system information. In Step ST3904, the mobile terminal performs reselection of a cell according to the priority order for a mobile terminal that does not have a CSG-ID in the white list received in the system information (for a mobile terminal not registered in the CSG cell).

  In Step ST3905, the mobile terminal determines whether the white list includes the CSG-ID. Alternatively, the mobile terminal determines whether it is registered in the CSG cell. If CSG-ID is included in the white list, or if it is registered in the CSG cell, the mobile terminal makes a transition to step ST3906. When CSG-ID is not included in the white list or when it is not registered in the CSG cell, the mobile terminal makes a transition to step ST3907. In Step ST3906, the mobile terminal performs reselection of the cell according to the priority order for the mobile terminal having the CSG-ID in the white list received by the individual signal (for the mobile terminal registered in the CSG cell), and in Step ST3805. Migrate to In Step ST3907, the mobile terminal performs reselection of the cell according to the priority order for the mobile terminal that does not have the CSG-ID in the white list received in the individual signal (for the unregistered mobile terminal to the CSG cell), The process proceeds to step ST3805. Here, the priority order that differs depending on whether or not the whitelist has a CSG-ID may be either the priority order notified by the system information or the priority order notified by the individual signal.

  Next, as a system information (step ST3901), a different priority notification method is disclosed depending on whether or not the whitelist has a CSG-ID. As a first method, the serving cell (network side) sends system information to the mobile terminal together with the priority order used when the whitelist has a CSG-ID and the priority order used when the whitelist does not have a CSG-ID. Is notified by PDSCH using BCCH. Furthermore, regardless of whether the serving cell is a CSG cell or a non-CSG cell, the priority used when the whitelist does not have a CSG-ID is used by the serving cell (network side) using BCCH as system information to the mobile terminal. Notification is made by PDSCH. In the first method, since the mobile terminal can obtain different priorities only by receiving the BCCH of the serving cell, the effect of preventing control delay can be obtained. As a second method, the priority used when the CSG-ID is not included in the white list is notified by the serving cell (network side) to the mobile terminal using the PDCH using BCCH as system information. Furthermore, regardless of whether the serving cell is a CSG cell or a non-CSG cell, both the priority used when the white list has a CSG-ID and the priority used when the white list does not have a CSG-ID are serving cells. The (network side) notifies the mobile terminal by PDSCH using BCCH as system information. The priority order used when the whitelist has a CSG-ID is reported by the CSCH cell to the mobile terminal in the system information and is reported on the PDSCH using the BCCH. It is possible to obtain an effect that the system information of the non-CSG cell does not need to be changed due to the introduction of CSG. This eliminates the need for changes in an LTE system (eUTRA / eUTRAN) that does not include an existing CSG, and improves compatibility.

  Next, when the CSG-ID is included in the white list notified from the base station (network side) to the mobile terminal by an individual signal, or when the CSG cell is registered in the CSG cell, the priority is given to the white list and the CSG is included in the white list. An RRC message can be considered as the priority order notification method for the case where the ID is not included or not registered in the CSG cell.

  The effects of the thirteenth embodiment will be described below. There is a possibility that a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list exist together under the base station. Priorities (such as different E-UTARAN frequencies or Inter-RAT frequency priorities) are separately assigned to a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list. Configurable. Thereby, the effect that the increase in control delay is prevented as a mobile communication system is acquired. The solution of the thirteenth embodiment is excellent in that the network side (base station or the like) has the above effect without knowing whether the corresponding mobile terminal has a CSG-ID in the white list. . Thereby, it is not necessary to notify the presence / absence of the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load on the base station in that the base station does not need to manage the presence / absence of CSG-ID in the white list of the mobile terminal being served.

Embodiment 14 FIG.
The problem in the fourteenth embodiment will be described below. As described in the thirteenth embodiment, in the prior art, the priority (different E-UTRAN frequency or Inter-RAT frequency priority) notified from the network side (base station) to the mobile terminal by an individual signal is effective. There was one time. As described above, CSG cells are introduced in LTE and UMTS. A user equipment that is not registered in any CSG cell, that is, a user equipment that does not have a CSG-ID in the white list, uses only non-CSG cells as a target for cell reselection. Therefore, it is considered that there is little change in the priority order. A user equipment registered in any CSG cell, that is, a user equipment having a CSG-ID in the white list, reselects not only the non-CSG cell but also the CSG cell. Therefore, the priority order is considered to change frequently. In such a situation in which the frequency of changing the priority order is different, if the effective time of the priority order is one, it is impossible to set an effective time suitable for each situation change, and the control delay increases. The problem of doing occurs. Furthermore, this problem occurs both when introducing a CSG cell into an LTE (E-UTRAN) system and when introducing a CSG cell into a W-CDMA (UTRAN, UMTS) system.

  A solution to the problem of the fourteenth embodiment is shown below. This solution is applicable to both LTE and W-CDMA systems. In the fourteenth embodiment, effective times (for example, different E-UTRAN frequencies or Inter-RAT frequency priorities) with different priorities depending on whether or not the whitelist has a CSG-ID in order to solve the above-described problem (for example, T320) is provided separately and is reflected in the mobile terminal. A specific operation example will be described with reference to FIG. In FIG. 40, the description of the same step number as in FIG. 38 is omitted. In Step ST4001, the mobile terminal determines whether or not the white list includes the CSG-ID. Alternatively, the mobile terminal determines whether it is registered in the CSG cell. When CSG-ID is included in the white list or when it is registered in the CSG cell, the mobile terminal makes a transition to step ST4002. If the CSG-ID is not included in the white list, or if it is not registered in the CSG cell, the mobile terminal moves to step ST4003. In Step ST4002, when the mobile terminal includes the CSG-ID in the white list in the effective time (for example, T320) of the priority (different E-UTRAN frequency or Inter-RAT frequency priority), or in the CSG cell The valid time (for example, T320_white list) is set for the priority order for registration (different E-UTRAN frequency or Inter-RAT frequency priority order), and the process proceeds to step ST3807.

  In Step ST4003, when the mobile terminal does not include the CSG-ID in the white list in the effective time (for example, T320) of the priority (different E-UTRAN frequency or Inter-RAT frequency priority), or in the CSG cell The effective time (for example, no T320_white list) of the priority order (the priority order of different E-UTRAN frequency or Inter-RAT frequency) for the case of not registering is set, and the process proceeds to step ST3807. When the white list contains a CSG-ID or when registered in a CSG cell, the priority valid time, and when the white list does not contain a CSG-ID or not registered in a CSG cell An RRC message and a broadcast control channel are conceivable as notification methods of valid times of priority for cases. When using an individual control channel, it is an excellent method in that control according to the communication state of the mobile terminal is possible. In the case of notification using the broadcast control channel, it is possible to notify all mobile terminals being served thereby, which is an excellent method in terms of effective use of radio resources. The fourteenth embodiment can be used together with the thirteenth embodiment. If the white list in that case contains a CSG-ID, or if it is registered in a CSG cell, the effective time of priority, and if the white list does not contain a CSG-ID, or is registered in a CSG cell The notification method of the effective time of the priority for the case where it is not used can be an RRC message and a broadcast control channel. In the case of notifying with the RRC message, it is further conceivable to notify with the priority order notified by the individual signal. In the case of notifying by the RRC message, it is excellent in that the complexity of the mobile communication system is avoided in that the priority order and the valid time of the priority order can be notified by the same notification method. Furthermore, it is excellent in that the control delay of the mobile communication system can be reduced by notifying both the priority order and the valid time of the priority order. In the case of notification using the broadcast control channel, it is possible to notify all mobile terminals being served thereby, which is an excellent method in terms of effective use of radio resources.

  The effects of the fourteenth embodiment are shown below. There is a possibility that a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list exist together under the base station. Separate priorities (such as different E-UTARAN frequencies or Inter-RAT frequency priorities) for a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list The effective time can be set. As a result, the effective time of the priority order can be set according to the frequency of the priority order change. Thereby, the effect that the increase in control delay is prevented as a mobile communication system is acquired. The solution of the fourteenth embodiment is excellent in that the network side (base station or the like) has the above effect without knowing whether the corresponding mobile terminal has a CSG-ID in the white list. . Thereby, it is not necessary to notify the presence / absence of the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load on the base station in that the base station does not need to manage the presence / absence of CSG-ID in the white list of the mobile terminal being served. By using both the embodiment 14 and the embodiment 13, it is possible to give priority to a mobile terminal having a CSG-ID in the white list and a flexible terminal suitable for a mobile terminal having no CSG-ID in the white list. Ranking can be set. Thereby, the effect that the increase in control delay is prevented as a mobile communication system is acquired.

Embodiment 15.
Non-Patent Document 6 (Chapter 10.1.1.2) and Non-Patent Document 7 (Chapter 5.2.4.2) disclose procedures for cell reselection as an LTE mobile communication system. The matters disclosed below will be described. A mobile terminal in the RRC_IDLE state performs cell reselection. The mobile terminal measures a serving cell and a neighbor cell in order to perform reselection. There is no need to indicate neighboring cells in the serving cell system information (for the purpose of mobile terminal searching and measuring cells). If the serving cell characteristics meet the search or measurement criteria, the measurement is omitted. In cell reselection, a mobile terminal authenticates a cell to be camp-on. Based on cell reselection criteria for serving cell measurements. Reselection between the same frequencies is based on cell ranking. The reselection between different frequencies is based on the absolute priority that the mobile terminal attempts to camp on to the highest priority frequency available. The absolute priority for reselection is provided only by the RPLMN that was the previously registered PLMN and is valid only within the RPLMN. The priority order is provided by the system information and is effective for all mobile terminals in the cell (mobile terminals being served by the cell). The special priority for each mobile terminal can be notified in an RRC connection release message. The valid time can be linked with the priority of each mobile terminal. It is possible to indicate layer-specific cell reselection parameters (for example, layer-specific offset) for adjacent cells between different frequencies. These parameters are common to all neighboring cells on the frequency. A Neighbor Cell List (NCL) can be provided to handle special cases where the serving cell is between the same frequency and between different frequencies. The neighbor cell list includes cell specific cell reselection parameters (eg, cell specific offsets) for specific neighbor cells. A black list can be provided so that the mobile terminal does not reselect neighboring cells between specific same frequencies and different frequencies. Cell reselection is speed dependent (can be speed dependent). Speed detection is based on the UTRAN solution. Cell reselection parameters can be applied to all mobile terminals in one cell, but specific reselection parameters can be set for each mobile terminal group and each mobile terminal.

  The flow of processing as a mobile terminal disclosed in FIG. 41 is shown. In Step ST4101, the mobile terminal performs cell selection or cell reselection, and moves to Step ST4102. In Step ST4102, the mobile terminal determines whether or not a measurement criterion for starting cell reselection is satisfied. Specifically, it is determined whether the reception quality of the serving cell is equal to or less than a threshold value. More specifically, it is determined whether or not S_ServingCell is equal to or less than S_intrasearch (or S_ServingCell is equal to or less than S_non intrasearch). If the measurement standard is satisfied, the mobile terminal makes a transition to step ST4103. If not, the process of step ST4102 is repeated. In Step ST4103, the mobile terminal performs measurement for cell reselection, and moves to Step ST4104. In Step ST4104, the mobile terminal determines whether to perform cell reselection based on the result of the measurement performed in Step ST4103. When performing cell reselection, it returns to step ST4101. When cell reselection is not performed, the process returns to step ST4102.

  CSG cells are introduced in LTE and UMTS. In the CSG cell, it is considered that an inexpensive charging system is set as compared with the non-CSG cell. Therefore, it is expected that the user wishes to camp on the CSG cell at a place where the CSG cell can be selected. Also, in a situation where a CSG cell exists in the coverage of a non-CSG cell as a mobile communication system, if the number of mobile terminals in charge of scheduling etc. increases, the processing load of the non-CSG cell is increased accordingly. Is reduced. Therefore, it is expected for the mobile communication system that a mobile terminal in a place where the CSG cell can be selected desires to camp on the CSG cell.

  The following problems occur in the cell reselection procedures described in Non-Patent Document 6 and Non-Patent Document 7. Consider a case where a CSG cell is installed in a non-CSG cell. Also, consider a case where a mobile terminal whose serving cell is a non-CSG cell exists within the coverage of the CSG cell. In this situation, if the measurement criteria of the mobile terminal are not satisfied, the reception quality of the serving cell (non-CSG cell) is greater than the threshold, and if S_ServingCell> S_intrasearch, the mobile terminal does not perform measurement for cell reselection. It will be. In step ST4102 of FIG. 41, it is determined that the measurement standard is not satisfied, and step ST4102 is repeated without performing the process of step ST4103. This means that the mobile terminal is not provided with an opportunity to reselect the CSG cell while being within the coverage of the CSG cell. Thereby, the subject that a user cannot receive the benefit of the charge plan of a CSG cell generate | occur | produces. In addition, the mobile communication system also has a problem that the load on the non-CSG cell cannot be reduced.

  The above problem is also disclosed in Non-Patent Document 8. Non-Patent Document 8 is a document for UTRA. Non-Patent Document 8 discloses the following method as a solution to the above problem. The mobile terminal should be able to search for the HNB even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch). In this case, the HNB search cycle is expected to be longer than a normally used search cycle. By not performing a search at a place where the HNB is not arranged, low power consumption of the mobile terminal is supported. This method uses a search cycle longer than the normally used search cycle only when the presence of HNB in the vicinity is indicated in the peripheral cell list of the non-CSG cell.

  The problem in the fifteenth embodiment will be described below. Since Non-Patent Document 8 is a document for UTRA, Non-Patent Document 8 does not disclose a solution to problems in EUTRAN (LTE system). Furthermore, Non-Patent Document 8 uses a neighbor cell list to support low power consumption of a mobile terminal. However, in the LTE system, as described above, it is not necessary for the mobile terminal to indicate the neighboring cell in the serving cell system information for the purpose of searching and measuring the cell. Therefore, it is impossible to directly apply the method for supporting the low power consumption of the mobile terminal using the neighboring cell list shown in Non-Patent Document 8 to the LTE system. Furthermore, as a new problem for the technique disclosed in Non-Patent Document 8, even when a CSG cell exists in a neighboring cell of a serving cell (non-CSG cell), the CSG cell is included in the white list of the mobile terminal. When not registered, there is no possibility that the mobile terminal selects the CSG cell as a suitable cell. Therefore, a mobile terminal that is not registered in the CSG cell uses the technique of Non-Patent Document 8 and the serving cell state is good just because a CSG cell exists in a neighboring cell of the serving cell (non-CSG cell) (Sx> Even if S_intrasearch, Sx> S_intersearch), the case where the search is started is considered. In that case, since it is impossible for the mobile terminal (not registered in the CSG cell) to select the CSG cell, useless measurement occurs, which causes a problem of increased power consumption of the mobile terminal.

  The problem solution of the fifteenth embodiment is shown below. In the fifteenth embodiment, cell reselection is applied even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch), which is applied when the whitelist has a CSG-ID in order to solve the above problem. It is disclosed that a period (a timer may be used) for performing measurement is provided and reflected on the mobile terminal. Or, when the mobile terminal is registered in the CSG cell, a period for performing cell reselection (may be a timer) is provided even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch) To be reflected in the mobile terminal. A specific operation example will be described with reference to FIG. In FIG. 42, the description of the same step number as in FIG. 41 is omitted. In Step ST4201, the mobile terminal determines whether or not the whitelist includes the CSG-ID. Alternatively, the mobile terminal determines whether it is registered in the CSG cell. When CSG-ID is included in the white list or when it is registered in the CSG cell, the mobile terminal makes a transition to step ST4202. When CSG-ID is not included in the white list, or when it is not registered in the CSG cell, the mobile terminal makes a transition to step ST4207. In Step ST4202, the mobile terminal starts a measurement cycle for cell reselection or a timer (for example, T_reselectCSG) applied when the whitelist has a CSG-ID, and moves to Step ST4203. Alternatively, a measurement cycle for cell reselection or a timer (for example, T_reselectCSG) applied when the mobile terminal is registered in the CSG cell is started, and the mobile terminal makes a transition to step ST4203.

  In Step ST4203, the mobile terminal determines whether or not it is a measurement cycle (for example, T_reselectCSG) for cell reselection applied when the whitelist has a CSG-ID. Alternatively, the mobile terminal determines whether or not a timer for cell reselection (for example, T_reselectCSG) applied when the whitelist has a CSG-ID has timed out (or timed out). When it is the measurement cycle or when the timer times out, the mobile terminal makes a transition to step ST4205. If it is not the measurement cycle or if the timer has not timed out, the mobile terminal makes a transition to step ST4204. In Step ST4204, the mobile terminal determines whether or not a measurement criterion for starting cell reselection is satisfied. Specifically, it is determined whether the reception quality of the serving cell is equal to or less than a threshold value. More specifically, it is determined whether or not S_ServingCell is equal to or lower than S_intrasearch (or S_ServingCell is equal to or lower than S_non intrasearch). When the measurement criterion is satisfied (when the reception quality of the serving cell is equal to or lower than the threshold, when S_ServingCell ≦ S_intrasearch), the mobile terminal makes a transition to step ST4205. If not, the process returns to step ST4203. In Step ST4205, the mobile terminal performs measurement for cell reselection, and moves to Step ST4206. In Step ST4206, the mobile terminal determines whether to perform cell reselection based on the result of the measurement performed in Step ST4205. When performing cell reselection, it returns to step ST4101.

  When cell reselection is not performed, the process returns to step ST4202. In Step ST4207, the mobile terminal determines whether or not a measurement criterion for starting cell reselection is satisfied. Specifically, it is determined whether the reception quality update of the serving cell is equal to or less than a threshold value. More specifically, it is determined whether or not S_ServingCell is equal to or less than S_intrasearch (or S_ServingCell is equal to or less than S_non intrasearch). If the measurement standard is satisfied, the mobile terminal makes a transition to step ST4208. If not, the process of step ST4207 is repeated. In Step ST4208, the mobile terminal performs measurement for cell reselection, and moves to Step ST4209. In Step ST4209, the mobile terminal determines whether to perform cell reselection based on the result of the measurement performed in Step ST4208. When performing cell reselection, it returns to step ST4101. When cell reselection is not performed, the process returns to step ST4207.

  Next, when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch), which is applied when the whitelist has a CSG-ID, the cycle for measuring the cell reselection (even with a timer) (For example, T_reselectCSG) is disclosed. As a first method, a serving cell (network side) notifies a mobile terminal by PBCH or PDSCH using BCCH as broadcast information.

  Further, the serving cell notifies the master information (MIB) using PBCH or the system information (SIB) using PDSCH. When the MIB is used, the MIB is mapped to the PBCH, which is an excellent method in that the mobile terminal can receive with a small control delay. When using SIB, it notifies using SIB1. MIB or SIB1 is an excellent method in that the control delay of the mobile terminal is reduced in that it is the broadcast information received at the minimum necessary for the operation waiting from the cell search. Further, even a method of notifying with system information other than SIB1 is broadcast information, so it can be notified to all mobile terminals being served thereby and is an excellent method in terms of effective use of radio resources. In the first method, the mobile terminal only receives the BCCH of the serving cell and is applied when the white list has a CSG-ID in the white cell list (Sx> S_intrasearch, Sx> S_intersearch). In addition, since a cycle (timer) for performing measurement for cell reselection can be obtained, an effect of preventing a control delay can be obtained. As a second method, the CSG cell notifies the user equipment by PBCH or PDSCH using BCCH as broadcast information. Further, the CSG cell notifies by PBCH using master information (MIB) or PDSCH using system information (SIB). When the MIB is used, the MIB is mapped to the PBCH, which is an excellent method in that the mobile terminal can receive with a small control delay. When using SIB, it notifies using SIB1. MIB or SIB1 is an excellent method in that the control delay of the mobile terminal is reduced in that it is the broadcast information received at the minimum necessary for the operation waiting from the cell search. Further, even a method of notifying with system information other than SIB1 is broadcast information, so it can be notified to all mobile terminals being served thereby and is an excellent method in terms of effective use of radio resources. It is possible to obtain an effect that the system information of the non-CSG cell does not need to be changed due to the introduction of CSG. This eliminates the need for changes in an LTE system (eUTRA / eUTRAN) that does not include an existing CSG, and improves compatibility. As a third method, the non-CSG cell notifies the user equipment via PBCH or PDSCH using BCCH as broadcast information. Further, the CSG cell notifies by PBCH using master information (MIB) or PDSCH using system information (SIB). When the MIB is used, the MIB is mapped to the PBCH, which is an excellent method in that the mobile terminal can receive with a small control delay. When using SIB, it notifies using SIB1. MIB or SIB1 is an excellent method in that the control delay of the mobile terminal is reduced in that it is the broadcast information received at the minimum necessary for the operation waiting from the cell search. Further, a notification method using system information other than SIB1 may be used. Since system information other than SIB1 is also broadcast information, it can be notified to all mobile terminals being served thereby, which is an excellent method in terms of effective use of radio resources. In order to select a CSG cell when the non-CSG cell is a serving cell, it is sufficient to notify the parameter from the non-CSG cell. Therefore, the third method is superior in terms of effective use of radio resources. As a fourth method, a static value is set as a mobile communication system (a value known in a mobile terminal / base station as a mobile communication system, a value described in a standard document). As a result, no radio signal is generated between the base station (network side) and the mobile terminal. Therefore, an effect can be obtained in terms of effective use of radio resources. Furthermore, since it is a statically determined value, it is possible to obtain the effect of preventing the occurrence of radio signal reception errors.

  In the above, a period (timer) is provided to perform measurement for cell reselection even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch), which is applied when the whitelist has a CSG-ID. However, the problem can be solved even if a different period (timer) is separately provided depending on whether or not the CSG-ID is included in the white list and reflected in the mobile terminal. In addition, in the above, a period (timer) for performing measurement for cell reselection even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch), which is applied when the whitelist has a CSG-ID However, even if it is a mobile terminal having a CSG-ID in the white list, the period may be applied only when the serving cell is a non-CSG cell. As a result, measurement for useless cell selection in the case where the serving cell already generated by the above solution is a CSG cell (since there is no need to change the serving cell from a non-CSG cell to a CSG cell, Even when the reception quality is good, the measurement for selecting the CSG cell is a useless measurement). This can achieve the effect of reducing the power consumption of the mobile terminal. In the above, LTE using HeNB using CSG has been described, but the present invention is UMTS using HNB using CSG, and HeNB, HNB not using CSG, and a base station with a small radius (also called a pico cell or macro cell). ) Is also applicable.

  The effects of the fifteenth embodiment are shown below. There is a possibility that a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list exist together under the base station. Applicable when the whitelist has a CSG-ID, and provides a period (may be a timer) for performing cell reselection measurement even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch) Accordingly, when the reception quality of the serving cell (non-CSG cell) is good, the user may benefit from the charging plan of the CSG cell, which occurs because the measurement for reselecting the CSG cell is not performed. The problem that it cannot be performed and the problem that the load of the non-CSG cell cannot be reduced can be solved even in the mobile communication system. If the serving cell is in good condition when the whitelist has a CSG-ID (if the measurement criteria are not met, Sx> S_intrasearch, Sx> S_intersearch) A mobile terminal that is not registered in a CSG cell that does not have a CSG-ID in the case where the serving cell is in a good condition as usual (when measurement criteria are not satisfied, Sx> S_intrasearch, Sx> S_intersearch) is measured for cell reselection. Do not do. As a result, it is possible to omit the measurement for selecting the CSG cell even when the serving cell that is wasted for the user equipment that cannot reselect the CSG cell due to unregistration in the CSG cell is good. . This can achieve the effect of reducing power consumption of mobile terminals that are not registered in the CSG cell. This effect is an effect of the present invention that cannot be obtained by the technique disclosed in Non-Patent Document 8. The solution of the fifteenth embodiment is excellent in that the problem can be solved without using the peripheral cell list. This is because, as described above, CSG cells, HeNBs, and HNBs are assumed to have portable sizes and weights, and it is assumed that installation and removal of these CSG cells and the like are performed frequently and flexibly. Therefore, in the solution using the neighboring cell list, it is necessary to update the neighboring cell list every time the CSG cell, HeNB, HNB, etc. are installed or removed, and it is expected that the neighboring cell list is frequently updated. . Therefore, the solution using the neighbor cell list results in a complicated and complicated mobile communication system. Furthermore, the solution of the fifteenth embodiment is excellent in that the network side (base station or the like) has the above effect without knowing whether the corresponding mobile terminal has a CSG-ID in the white list. Yes. Thereby, it is not necessary to notify the presence / absence of the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load on the base station in that the base station does not need to manage the presence / absence of CSG-ID in the white list of the mobile terminal being served.

  Next, a first modification of the fifteenth embodiment will be described. In the fifteenth embodiment, a cycle for performing measurement for cell reselection, even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch), which is applied when the whitelist has a CSG-ID. (Timer may be used) and the problem was solved by reflecting it on the mobile terminal. However, it is unclear whether a CSG cell existing around the current serving cell can be an appropriate cell (suitable cell) just because the whitelist has a CSG-ID. If the cell is not registered in the CSG cell existing around the current serving cell, even if the serving cell is in good condition, performing measurement for cell reselection increases the power consumption of the mobile terminal. The problem occurs. This is a problem that occurs when a user registered in a CSG cell installed in a company returns home.

  A problem solution in the first modification of the fifteenth embodiment will be described below. The first modification of the fifteenth embodiment is a case where the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch), which is applied when the whitelist has a CSG-ID in order to solve the above problem. Even if the cell is not selected even though the measurement for cell selection is performed in the cycle for measuring the cell reselection (may be a timer), the serving cell is in good condition. It is disclosed that an offset is added to a cycle for performing measurement for cell reselection and reflected in a mobile terminal. A specific operation example will be described with reference to FIG. In FIG. 43, the description of the same step number as in FIG. 42 is omitted. In step 4301, the mobile terminal adds an offset value to a cycle (timer) (for example, T_reselectCSG) for performing measurement for cell reselection even when the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch) The process proceeds to step ST4202. For example, if this offset value is a positive value, the cell reselection is measured but the cell is not reselected even if the serving cell is in good condition (Sx> S_intrasearch, Sx> S_intersearch) In other words, if a CSG cell that is an appropriate cell (Suitable cell) for the mobile terminal is not found, even if the serving cell is in good condition, the period for performing measurement for cell reselection is extended. . Therefore, by using the offset value, it is possible to reduce the power consumption of the mobile terminal when it is not registered in the CSG cell existing around the current serving cell. This offset value notification method can use the cycle (timer) notification method for performing measurement for cell reselection even when the serving cell state in the fifteenth embodiment is good. At this time, even when the offset value and the state of the serving cell are good, the notification of the period (timer) for performing measurement for cell reselection may be simultaneous or separate.

  In the above, LTE using HeNB using CSG has been described, but the present invention is UMTS using HNB using CSG, and HeNB, HNB not using CSG, and a base station with a small radius (also called a pico cell or macro cell). ) Is also applicable.

  In the first modification of the fifteenth embodiment, the following effects can be obtained in addition to the effects of the fifteenth embodiment. It is possible to reduce the power consumption of the mobile terminal when it is not registered in the CSG cell existing around the current serving cell. Furthermore, the network side (base station or the like) has the above effect without knowing which CSG cell the corresponding mobile terminal is registered in (which CSG-ID is in the white list). The solution of the first modification of the fifteenth embodiment is excellent. Thereby, it is not necessary to notify the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load of the base station in that the base station does not need to manage the CSG-ID in the white list of the mobile terminal being served.

  Next, a second modification of the fifteenth embodiment will be described. About the subject shown with the 1st modification of Embodiment 15, the solution different from the 1st modification of Embodiment 15 is disclosed. The second modification of the fifteenth embodiment is a case where the serving cell state is good (Sx> S_intrasearch, Sx> S_intersearch), which is applied when the whitelist has a CSG-ID in order to solve the above problem. In the case where the serving cell is in good condition when the cell cannot be selected even though the measurement for the cell selection is performed in the cycle for measuring the cell reselection (may be a timer). Also discloses canceling the application of the period for performing measurements for cell reselection. A specific operation example will be described with reference to FIG. In FIG. 44, the description of the same step number as in FIG. 42 is omitted. In Step ST4206, the mobile terminal determines whether cell reselection has been performed based on the result of the measurement performed in Step ST4205. If cell reselection is performed, the process returns to step ST4101. When cell reselection is not performed, the mobile terminal makes a transition to step ST4207.

  In the above, LTE using HeNB using CSG has been described, but the present invention is UMTS using HNB using CSG, and HeNB, HNB not using CSG, and a base station with a small radius (also called a pico cell or macro cell). ) Is also applicable.

  In the second modification of the fifteenth embodiment, the following effects can be obtained in addition to the effects of the fifteenth embodiment. It is possible to reduce the power consumption of the mobile terminal when it is not registered in the CSG cell existing around the current serving cell. Furthermore, the network side (base station or the like) has the above effect without knowing which CSG cell the corresponding mobile terminal is registered in (which CSG-ID is in the white list). The solution of the second modification of the fifteenth embodiment is excellent. Thereby, it is not necessary to notify the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load of the base station in that the base station does not need to manage the CSG-ID in the white list of the mobile terminal being served.

Embodiment 16 FIG.
In the sixteenth embodiment, a solution different from the fifteenth embodiment is disclosed for the problem shown in the fifteenth embodiment. Further, in the current cell reselection procedure, the following operation can be considered in order to select the CSG cell of the neighboring cell even when the reception quality of the serving cell that is a non-CSG cell is good. For example, S_intrasearch is set low. Accordingly, even when the reception quality of the serving cell is good, the measurement standard is easily satisfied, and measurement for cell reselection is easily performed. However, when S_intrasearch is lowered as described above, even if all mobile terminals (including mobile terminals that do not have a CSG-ID in the white list) under the serving cell have a good serving cell reception status. Measurement criteria are easily satisfied, and measurement for cell reselection is easily performed. In that case, since it is impossible for the mobile terminal (not registered in the CSG cell) to select the CSG cell, useless measurement occurs, which causes a problem of increased power consumption of the mobile terminal.

  In the sixteenth embodiment, in order to solve the above problem, the measurement criteria for starting cell reselection are divided into a case where CSG-ID is included in the white list and a case where CSG-ID is not included in the white list. It is disclosed that it is provided and reflected on the mobile terminal. More specifically, the threshold for comparing with the reception quality of the serving cell, which is a metric for initiating cell reselection, when the CSG-ID is included in the whitelist and when the CSG-ID is not included in the whitelist Disclosed separately for each case and reflected on the mobile terminal. A specific operation example will be described with reference to FIG. In FIG. 45, the description of the same step number as in FIGS. 41 and 42 is omitted. In Step ST4201, the mobile terminal determines whether or not the whitelist includes the CSG-ID. Alternatively, the mobile terminal determines whether it is registered in the CSG cell. When CSG-ID is included in the white list, or when registered in the CSG cell, the mobile terminal makes a transition to step ST4501. When CSG-ID is not included in the white list or when it is not registered in the CSG cell, the mobile terminal makes a transition to step ST4502. In Step ST4501, the mobile terminal determines whether or not a measurement criterion for cell reselection applied when the whitelist has a CSG-ID is satisfied. As a specific example, it is determined whether or not the reception quality (for example, Sx) of the serving cell is equal to or lower than a threshold value (for example, S_intrasearchCSG) that is applied when the whitelist has a CSG-ID.

  When the measurement criteria are satisfied, as a specific example, when Sx ≦ S_intrasearchCSG, the process proceeds to step ST4205. When the measurement standard is not satisfied, as a specific example, when Sx> S_intrasearchCSG, the process returns to step ST4501. In this case, you may compare with the threshold value (for example, S_intersearchCSG) of not only the threshold value of whether the measurement standard between the same frequencies is satisfied, but whether the measurement standard of different frequencies is satisfied. In Step ST4502, the mobile terminal determines whether or not the measurement standard for cell reselection to be applied normally (may be a case where the whitelist does not have CSG-ID) is satisfied. As a specific example, it is determined whether or not the reception quality (for example, Sx) of the serving cell is equal to or less than a threshold value (S_intrasearch). When the measurement criteria are satisfied, as a specific example, when Sx ≦ S_intrasearch, the process proceeds to step ST4208. When the measurement standard is not satisfied, as a specific example, when Sx> S_intrasearch, the process returns to step ST4502. In this case, you may compare with the threshold value (for example, S_intersearch) whether it meets not only the threshold value of whether the measurement standard between the same frequencies is satisfied, but also the measurement standard between different frequencies. In addition, when a serving cell is a non-CSG cell even if it is a mobile terminal having a CSG-ID in the white list, a threshold (for example, S_intersearchCSG) applied when the white list disclosed above has a CSG-ID is used. May apply only. As a result, when the serving cell generated in the above solution is a CSG cell, measurement for useless cell selection (since there is no need to change the serving cell from a non-CSG cell to a CSG cell, Even when the reception quality is good, the measurement for selecting the CSG cell is a useless measurement). This can achieve the effect of reducing the power consumption of the mobile terminal.

  The metric notification method for starting cell reselection when CSG-ID is included in the whitelist performs measurement for cell reselection even when the serving cell state is good in the fifteenth embodiment. A period (timer) notification method can be used. At this time, the notification of the metric for initiating cell reselection when the whitelist has a CSG-ID may be simultaneous with or separate from the metric for cell reselection that is normally applied. Absent.

  In the above, LTE using HeNB using CSG has been described, but the present invention is UMTS using HNB using CSG, and HeNB, HNB not using CSG, and a base station with a small radius (also called a pico cell or macro cell). ) Is also applicable.

  The effects of the sixteenth embodiment are shown below. There is a possibility that a mobile terminal having a CSG-ID in the white list and a mobile terminal not having a CSG-ID in the white list exist together under the base station. A CSG cell is re-established when the reception quality of the serving cell (non-CSG cell) is good by providing a metric for initiating cell reselection, which is applied when the white list has a CSG-ID. The problem that the user cannot benefit from the billing plan of the CSG cell, which is caused by not performing the measurement for selection, and that the load of the non-CSG cell cannot be reduced even in the mobile communication system. The problem can be solved. Even if the white list has a CSG-ID, even if the serving cell is in good condition, the mobile terminal performs measurement for cell reselection and is not registered in a CSG cell that does not have a CSG-ID in the white list. Does not perform measurement for cell reselection when the serving cell is in good condition as before. As a result, it is possible to omit the measurement for selecting the CSG cell even when the serving cell that is wasted for the user equipment that cannot reselect the CSG cell due to unregistration in the CSG cell is good. . This can achieve the effect of reducing power consumption of mobile terminals that are not registered in the CSG cell. This effect is an effect of the present invention that cannot be obtained by the technique disclosed in Non-Patent Document 8.

  The solution of the sixteenth embodiment is excellent in that the problem can be solved without using the peripheral cell list. This is because, as described above, CSG cells, HeNBs, and HNBs are assumed to have portable sizes and weights, and it is assumed that installation and removal of these CSG cells and the like are performed frequently and flexibly. Therefore, in the solution using the neighboring cell list, it is necessary to update the neighboring cell list every time the CSG cell, HeNB, HNB, etc. are installed or removed, and it is expected that the neighboring cell list is frequently updated. . Therefore, the solution using the neighbor cell list results in a complicated and complicated mobile communication system. Furthermore, the solution of the sixteenth embodiment is excellent in that the above effect is achieved without the network side (base station or the like) knowing whether the corresponding mobile terminal has a CSG-ID in the whitelist. Yes. Thereby, it is not necessary to notify the presence / absence of the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load on the base station in that the base station does not need to manage the presence / absence of CSG-ID in the white list of the mobile terminal being served.

  Next, a first modification of the above-described embodiment 16 will be described. Specifically, a solution for the problem shown in the first modification of the fifteenth embodiment is disclosed. In the first modification of the sixteenth embodiment, in order to solve the above problem, cell selection is performed using a metric for starting cell reselection (for example, S_intrasearchCSG), which is applied when the whitelist has a CSG-ID. Disclosing the application of a metric (eg, S_intrasearchCSG) for initiating cell reselection when a cell could not be selected despite the measurement for. A specific operation example will be described with reference to FIG. In Step ST4206, the mobile terminal determines whether cell reselection has been performed based on the result of the measurement performed in Step ST4205. If cell reselection is performed, the process returns to step ST4101. When cell reselection is not performed, the mobile terminal makes a transition to step ST4502.

Embodiment 17
In 3GPP, base stations called Home-NodeB (Home-NB, HNB) and Home-eNodeB (Home-eNB, HeNB) are being studied. HNB / HeNB is a base station for UTRAN / E-UTRAN, for example, for home, corporate, and commercial access services. Non-Patent Document 9 discloses three different modes of access to HeNB and HNB. An open access mode, a closed access mode, and a hybrid access mode. Each mode has the following characteristics. In the open access mode, the HeNB or HNB is operated as a normal cell of a normal operator. In the closed access mode, the HeNB or HNB is operated as a CSG cell. A CSG cell is a cell accessible only to CSG members. In the hybrid access mode, a non-CSG member is a CSG cell to which access is permitted at the same time. In other words, the cell in the hybrid access mode is a cell that supports both the open access mode and the closed access mode. A cell in the hybrid access mode is also called a hybrid cell.

  In 3GPP, a method for enabling cell reselection to a desired CSG cell even when reception quality of the serving cell is good is being studied. This is considered to be necessary for a hybrid cell. For example, in Non-Patent Document 10, in a hybrid cell, a CSG member UE should remain longer than a non-CSG member UE, and therefore, a CSG member UE and a non-CSG member UE have a camping mechanism. Proposals have been made that they need to be different. However, Non-Patent Document 10 does not describe any specific method.

  Since the hybrid cell is a CSG cell, as a specific method for the CSG member UE to stay longer than the non-CSG member UE in the hybrid cell, the fifteenth embodiment, the first modification of the fifteenth embodiment, Embodiment 15 The method disclosed in the second modification, the sixteenth embodiment, and the first modification of the sixteenth embodiment can be applied. By these methods, even if the serving cell is in good condition, a UE having a CGS-ID in a white list (CSG-ID list, allowed CSG list) or a UE registered in a CSG cell is not a UE It becomes possible to execute the cell reselection procedure earlier. For this reason, it becomes possible to detect a CSG cell including a hybrid cell quickly. Therefore, the UE having the CSG-ID of the CSG to which the hybrid cell belongs or the UE registered in the CSG can quickly perform cell reselection to the hybrid cell. The method disclosed in the above embodiment can also be applied to specific operations.

  In the sixteenth embodiment, it has been disclosed that the cell reselection measurement criteria are provided separately for the case where the whitelist has a CSG-ID and the case where it does not. As an example, the threshold for cell reselection when the CSG-ID is not included in the whitelist is S_intrasearch, and the threshold for cell reselection when the CSG-ID is included in the whitelist is S_intrasearchCSG.

  S_intrasearchCSG is set lower than S_intrasearch (S_intrasearch>) so that the cell reselection procedure is performed faster when the whitelist has CSG-ID than when the whitelist does not have CSG-ID. S_intrasearchCSG) should be set. The lower the cell reselection threshold, the easier it is to start the cell reselection procedure. As a result, the UE of the CSG member can easily make the cell reselection to the CSG cell sooner. Therefore, in the seventeenth embodiment as well, it is possible to facilitate cell reselection quickly to a hybrid cell as well.

Embodiment 18
As a specific method for enabling cell reselection to a desired CSG cell even when reception quality of the serving cell is good, for example, Non-Patent Document 11 describes a method of giving Qoffset for each CSG cell.

  Qoffset is an offset given to the received quality measurement value of the detected cell when performing cell ranking during cell reselection, as shown in Non-Patent Document 7. Qoffset is reported from the serving cell together with information on the cell to which the Qoffset is given.

  For example, Non-Patent Document 12 describes a method of giving one Qoffset to a hybrid cell, in other words, a method of giving one Qoffset to all cells in the hybrid access mode. Furthermore, a method is shown in which two Qoffsets corresponding to the RSRP range of the macro cell are provided, and each Qoffset is applied above and below a certain threshold of the RSRP of the macro cell.

  Just by giving Qoffset for each CSG cell or one hybrid cell or corresponding to the RSRP range of the macro cell as in these methods, the positional relationship with each cell, each cell type, or the macro cell Only the offset value can be changed for each.

  However, although the hybrid cell is a CSG cell, it supports both the open access mode and the closed access mode simultaneously. For this reason, for a hybrid cell, the criteria for cell reselection cannot be made different between a UE of a non-CSG member and a UE of a CSG member. Therefore, in these methods, there arises a problem that the UE of the CSG member cannot stay longer than the UE of the non-CSG member in the hybrid cell.

  In order to solve this problem, in the present embodiment, an offset value (Qoffset_csg) applied to a UE having a CSG-ID in the white list or a UE registered in the CSG and an offset value ( Qoffset_noncsg) is provided.

  In this way, by providing an offset separately for UEs having a CSG-ID in the whitelist or for UEs registered in the CSG and for UEs that are not registered, the criteria for cell reselection can be made non-CSG member UEs. And CSG member UEs can be different. Thereby, also in a hybrid cell, it becomes possible for CSG member UE to stay longer than non-CSG member UE.

  A specific operation example will be described with reference to FIG. In FIG. 46, the description of the same step number as in FIG. 41 is omitted. In ST4103, the UE performs measurement for cell reselection and performs cell ranking. In Step ST4601, the UE determines whether or not the white list includes a CSG-ID. Alternatively, the UE determines whether or not it is registered in the CSG cell. If CSG-ID is included in the white list or if it is registered in the CSG cell, the mobile terminal moves to ST4602. In ST4602, the UE subtracts Qoffset_csg from the measured value. If the CSG-ID is not included in the white list, or if it is not registered in the CSG cell, the mobile terminal moves to ST4603. In ST4603, the UE subtracts Qoffset_noncsg from the measured value. By performing cell ranking based on these subtracted results, a criterion for reselecting a cell between a UE having a CSG-ID in the white list or a UE registered in the CSG and a UE not having the CSG-ID is determined. It is possible to make it different. It is possible to set the cell ranking to only step ST4602 or step ST4603 and omit the cell ranking in step ST4103.

  Regarding the values of Qoffset_noncsg and Qoffset_csg, depending on the radio wave environment of the serving cell and the neighboring cells, the UE that has the CSG-ID in the whitelist or the UE registered in the CSG is faster than the UE that is not so. It may be set so as to satisfy the selected reception quality standard.

  For example, the value of Qoffset_csg is set lower than the value of Qoffset_noncsg (Qoffset_noncsg> Qoffset_csg). By doing so, the result calculated considering these offsets for a certain cell is that UEs with CSG-ID in the whitelist or UEs registered in the CSG are better than UEs that are not Get higher. Therefore, a UE having a CSG-ID in the white list or a UE registered in the CSG satisfies the reception quality standard for cell reselection earlier than a UE that does not. By satisfying the reception quality standard for cell reselection earlier, it becomes possible to perform reselection to a suitable cell earlier. Therefore, the CSG member UE can be re-selected for the hybrid cell earlier than the non-CSG member UE, and the CSG member UE can be kept longer than the non-CSG member UE. Become.

  As a criteria for cell ranking, the following equation may be used.

For UEs with a CSG-ID in the whitelist or UEs registered with the CSG,
Rn = Qmeas, n−Qoffset_csg
And for UEs that are not
Rn = Qmeas, n−Qoffset_noncs
And

  Qmeas, n is a reception quality measurement value of the nth cell, and Rn is a reception quality calculation result in consideration of an offset.

  Alternatively, the following formula may be used as the criteria for cell ranking.

For UEs with a CSG-ID in the whitelist or UEs registered with the CSG,
Rn = Qmeas, n−Qoffset−Qoffset_csg
And UEs that are not
Rn = Qmeas, n−Qoffset−Qoffset_noncsg
And

  In consideration of the conventional Qoffset, Qoffset_noncsg and Qoffset_csg can be used only for making a difference between a UE having a CSG-ID in the whitelist or a UE registered in the CSG and a UE that is not.

  As the Qoffset_csg and Qoffset_noncsg notification methods, the first to fourth methods disclosed in the fifteenth embodiment as the cycle notification methods for performing measurements for cell reselection can be applied. When these are applied, the same effect can be obtained.

  In the first method, when SIB is used, notification may be performed using SIB4. In SIB4, the conventional offset value is transmitted together with the information of the corresponding cell. By transmitting the offset value together with the information, cell ranking criteria can be executed for each corresponding cell together with the conventional offset value. A PCI range that can be given for the hybrid cell may be used as the corresponding cell information. By doing so, the same value can be set for a plurality of hybrid cells, and the amount of information of SIB4 can be reduced.

  In the second method, only the hybrid cell may notify the offset value as broadcast information.

  In the method disclosed above, an offset value (Qoffset_csg) to be applied to a UE having a CSG-ID or a UE registered in the CSG and an offset value (Qoffset_noncsg) to be applied to a UE not so are provided in the whitelist, Cell ranking was performed using and cell reselection was performed.

  As another method, a difference value (Qoffset_delta) between an offset value applied to a UE having a CSG-ID or a UE registered in the CSG and an offset value applied to a UE that is not so may be provided in the whitelist. . That is, Qoffset_noncsg and Qoffset_delta may be provided and used for cell ranking criteria.

  For example, the following formula may be used as a criterion for cell ranking.

For UEs with a CSG-ID in the whitelist or UEs registered with the CSG,
= Qmeas, n- (Qoffset_noncsg-Qoffset_delta)
And for UEs that are not
= Qmeas, n-Qoffset_noncsg
And

  Thereby, an effect equivalent to the method of notifying Qoffset_noncsg and Qoffset_csg disclosed above can be obtained.

  As another method, an offset value applied to a UE that does not have a CSG-ID in the white list or a UE that is not registered in the CSG is set as a conventional Qoffset, and is used together with the difference value Qoffset_delta. Also good.

  For example, the following formula may be used as a criterion for cell ranking.

For UEs with a CSG-ID in the whitelist or UEs registered with the CSG,
Rn = Qmeas, n− (Qoffset−Qoffset_delta)
And UEs that are not
Rn = Qmeas, n−Qoffset
And

  Thereby, not only an effect equivalent to the method disclosed above can be obtained, but also the parameter to be set can be reduced by one. That is, it is not necessary to set both Qoffset_csg and Qoffset_noncsg, and it is only necessary to set Qoffset_delta. Therefore, it is possible to reduce the amount of information for parameter setting. The method described above can be applied as the notification method. As another method, Qoffset and Qoffset_delta may be reported from different cells. For example, Qoffset is notified from the serving cell, and Qoffset_delta is notified from the hybrid cell. Since Qoffset_delta is a value used only for the hybrid cell, the UE having a CSG-ID in the white list or the UE registered in the CSG is used in the cell ranking criteria by notifying only from the hybrid cell. The recalculation may be performed using the offset value (Qoffset_delta). UEs that are not so do not need to recalculate and do not need to receive the offset value of the hybrid cell, so it is only necessary to measure the reception quality. Therefore, the measurement at the time of cell reselection can be simplified, and the effect of reducing the power consumption of the UE can be obtained.

  The method disclosed in this embodiment is a method of giving Qoffset for each CSG cell shown in Non-Patent Document 11, a method of giving one Qoffset to a hybrid cell shown in Non-Patent Document 12, or a macrocell The present invention can also be applied to a method in which two Qoffsets corresponding to the RSRP range are provided and each Qoffset is applied above and below a certain threshold value of the RSRP of the macro cell. For example, these Qoffsets may be used as the Qoffset in the cell ranking criteria disclosed in the present embodiment or in addition to the Qoffset. Thereby, for example, it is possible to consider each Qoffset for each CSG cell, for each hybrid, or corresponding to the RSRP range of the macro cell.

  As another method, the values shown in these non-patent documents are applied to UEs that do not have the offset value applied to UEs having a CSG-ID in the whitelist or UEs registered in the CSG. Do not. For example, the values shown in these non-patent documents may be used for Qoffset_delta as cell ranking criteria. By doing so, it becomes possible to make the criteria for cell reselection different between non-CSG member UEs and CSG member UEs for hybrid cells.

  The method disclosed in the present embodiment includes the fifteenth embodiment, the first modification of the fifteenth embodiment, the second modification of the fifteenth embodiment, the sixteenth embodiment, the first modification of the sixteenth embodiment, It can be used in combination with the method disclosed in Embodiment Mode 17.

  For example, FIG. 47 shows a specific operation example when combined with the fifteenth embodiment. In FIG. 47, the description of the same step number as in FIG. 42 is omitted. In Step ST4201, the UE judges whether or not the whitelist includes CSG-ID. Alternatively, the UE determines whether or not it is registered in the CSG cell. If CSG-ID is included in the white list or registered in the CSG cell, Qoffset_csg is subtracted from the measured value in ST4701. When CSG-ID is not included in the white list or when it is not registered in the CSG cell, Qoffset_noncsg is subtracted from the measured value in ST4702. By performing cell ranking based on these subtracted results, a criterion for reselecting a cell between a UE having a CSG-ID in the white list or a UE registered in the CSG and a UE not having the CSG-ID is determined. It is possible to make it different. It is also possible to set the cell ranking to only step ST4701 or step ST4702, and omit the cell ranking in step ST4205 or step ST4208.

  Other embodiments and modifications can be used in combination by performing the same operation. By combining the method disclosed in the present embodiment with these embodiments and modifications, it is possible to flexibly cope with differences in radio wave environments due to flexible arrangement of HeNBs or HNBs including hybrid cells. Is obtained.

  By adopting the method disclosed in the present embodiment, it becomes possible to make the criteria for cell reselection different between the UE of the non-CSG member and the UE of the CSG member for the hybrid cell. Thereby, also in a hybrid cell, it becomes possible for CSG member UE to stay longer than non-CSG member UE.

  As a result, the CSG member can receive services such as high-speed communication and preferential billing plans for the CSG member in a hybrid cell faster and longer.

Embodiment 19
In Embodiment 18, the CSG member UE performs cell reselection earlier to the hybrid cell than the non-CSG member UE, in other words, the method of facilitating reselection to the hybrid cell (inbound). Disclosed.

  In the present embodiment, the CSG member UE performs cell reselection later from the hybrid cell than the non-CSG member UE, in other words, it is difficult to perform cell reselection from the hybrid cell (outbound). In the list, an offset value (Qoffset_csg) to be applied to a UE having a CSG-ID or a UE registered in the CSG and an offset value (Qoffset_noncsg) to be applied to a UE not to be provided are provided, and cell ranking and cell re-transmission are performed using them. Disclosed is a case of applying a method in which selection is performed so that a cell reselection criterion differs between a non-CSG member UE and a CSG member UE.

  As a specific example of operation, the criteria for cell ranking may be expressed by the following equation.

For UEs with a CSG-ID in the whitelist or UEs registered with the CSG,
Rs = Qmeas, s + Qhyst-Qoffset_csg
And for UEs that are not
Rs = Qmeas, s + Qhyst-Qoffset_noncsg
And

  Qmeas, s is a reception cell measurement value of the serving cell, Qhyst is an offset value for providing hysteresis, and Rs is a calculation result of the reception quality of the serving cell in consideration of the offset.

  In reselection from the hybrid cell, the hybrid cell becomes the serving cell. Therefore, in order to make it difficult to reselect a cell from a hybrid cell, a UE having a CSG-ID in a whitelist or a UE registered in the CSG is included in the measured value of the serving cell during cell ranking at the time of cell reselection. Make a difference between UEs that do not and those that do not. As a specific example, calculation is performed using Qoffset_noncsg and Qoffset_csg when Rs is derived. Thereby, it becomes possible to change the judgment criteria which perform cell reselection from a hybrid cell by both UE.

  Regarding the values of Qoffset_noncsg and Qoffset_csg, depending on the radio wave environment of the serving cell and the neighboring cells, the UE that has the CSG-ID in the whitelist or the UE registered in the CSG is slower than the UE that is not so. It may be set so as to satisfy the selected reception quality standard.

  For example, the value of Qoffset_csg is set higher than the value of Qoffset_noncsg (Qoffset_noncsg <Qoffset_csg). By doing so, the calculation result in consideration of these offsets for the serving cell that is a hybrid cell shows that the UE having the CSG-ID in the whitelist or the UE registered in the CSG is more than the UE that is not so. Also lower. Therefore, a UE having a CSG-ID in the white list or a UE registered in the CSG satisfies the reception quality criterion for cell reselection later than a UE that does not.

  By satisfying the reception quality criterion for cell reselection later, it is possible to prevent reselection from the hybrid cell until later. Therefore, in the hybrid cell, the CSG member UE can re-select the cell later than the non-CSG member UE, and the CSG member UE can remain longer than the non-CSG member UE.

  FIG. 48 shows a specific operation example of cell reselection in a hybrid cell. In FIG. 48, the description of the same step number as in FIG. 41 is omitted. The UE that has entered the cell selection or cell reselection procedure in ST 4101 measures the serving cell for cell reselection, and performs cell ranking criteria for the serving cell. In Step ST4801, the UE determines whether or not the whitelist includes a CSG-ID. Alternatively, the UE determines whether or not it is registered in the CSG cell. If the whitelist includes a CSG-ID or if it is registered in a CSG cell, the mobile terminal moves to ST4802. In ST4802, the UE subtracts Qoffset_csg from the measured value. If the CSG-ID is not included in the white list, or if it is not registered in the CSG cell, the mobile terminal moves to ST4803. In ST4803, the UE subtracts Qoffset_noncsg from the measured value. Based on these subtracted results, in ST4102, it is determined whether or not the measurement criteria for cell reselection are satisfied. By doing so, it is possible to make different criteria for performing cell reselection between a UE having a CSG-ID in the white list or a UE registered in the CSG and a UE that is not.

  The offset values (Qoffset_csg, Qoffset_noncsg) may not be used when deriving the measurement value of the serving cell when performing cell ranking including the reception quality measurement value of the serving cell in ST4103. When not used, it is possible to increase the possibility that the CSG member UE selects the serving cell.

  Separately, an offset value (Qoffset_csg_r) applied to a UE having a CSG-ID or a UE registered in the CSG in the whitelist and an offset value (Qoffset_noncsg_r) applied to a UE not so are provided, and in ST4103, the serving cell When derivation of the measurement value of the serving cell when performing cell ranking including the reception quality measurement value, cell ranking may be performed by applying them to the measurement value of the serving cell, and cell reselection may be performed. In this case, Qoffset_noncsg_r may be set higher than Qoffset_csg_r. By doing so, the calculation result in consideration of these offsets for the serving cell that is a hybrid cell shows that the UE having the CSG-ID in the whitelist or the UE registered in the CSG is more than the UE that is not so. Also gets higher. Therefore, a UE having a CSG-ID in the white list or a UE registered in the CSG can be more likely to select a serving cell than a UE that does not.

  By making the cell ranking criteria as described above, in a hybrid cell, it becomes possible for the CSG member UE to re-select the cell later than the non-CSG member UE, and the CSG member UE becomes a non-CSG member. It is possible to stay in the hybrid cell longer than the UE.

  As the notification method of these parameters, the first method to the fourth method disclosed as the notification method of the period for performing the measurement for cell reselection in Embodiment 15 can be applied, and the same effect can be obtained. .

  By combining the present embodiment and the eighteenth embodiment, it becomes easier for the CSG member UE to reselect to the hybrid cell than the non-CSG member UE, and it is difficult to reselect from the hybrid cell. It becomes possible to make it. Accordingly, the CSG member UE can stay in the hybrid cell longer than the non-CSG member UE.

  When this embodiment and Embodiment 18 are combined, an offset value provided to facilitate reselection to a hybrid cell by a CSG member UE than a non-CSG member UE, and a cell from the hybrid cell The offset values provided to make reselection difficult may be set to different values or the same value.

  For example, the offset values provided to facilitate reselection to the hybrid cell are Qoffset_csg_in and Qoffset_noncsg_in, and the offset values provided to make cell reselection from the hybrid cell difficult are Qoffset_csg_out and Qoffset_noncsg_out, respectively. Can be set. By doing so, it becomes possible to deal with more flexible installation and operation of HeNB and HNB.

  As an example of setting the same value, two offsets Qoffset1 and Qoffset2 may be provided. In order to facilitate reselection to a hybrid cell, Qoffset_csg = Qoffset1 and Qoffset_noncsg = Qoffset2 are set and used in deriving the cell ranking Rn of neighboring cells. On the other hand, in order to make it difficult to reselect a cell from a hybrid cell, Qoffset_csg = Qoffset2 and Qoffset_noncsg = Qoffset1 are set and used in deriving the cell ranking Rs of the serving cell. Qoffset1 is preferably set lower than Qoffset2. By doing so, the number of parameters can be reduced, and the amount of information transmitted to the UE can be reduced.

  As the notification method of these parameters, the notification methods disclosed in the fifteenth embodiment and the eighteenth embodiment are possible, and combinations of various notification methods are also possible.

  For example, Qoffset_csg_in and Qoffset_noncsg_in are used for derivation of the cell ranking Rn of the neighboring cells, so that they are notified from the serving cell by SIB4. You may make it notify by.

  By doing so, it is possible to reduce the amount of information notified from a cell that is not a hybrid cell.

  When two offsets of Qoffset1 and Qoffset2 are provided, notification may be made with SIB1 of all cells. By doing so, it is possible to reduce the amount of information to be notified even in the hybrid cell.

  The method disclosed in the present embodiment includes the fifteenth embodiment, the first modification of the fifteenth embodiment, the second modification of the fifteenth embodiment, the sixteenth embodiment, the first modification of the sixteenth embodiment, It can be used in combination with the methods disclosed in the seventeenth embodiment and the eighteenth embodiment.

  By combining the method disclosed in the present embodiment with these embodiments and modifications, CSG members can be used even in various radio wave environments associated with flexible arrangement of HeNBs or HNBs including hybrid cells. UEs can reselect to a hybrid cell more easily than non-CSG member UEs, and reselection from the hybrid cell can be made difficult. Therefore, the UE of the CSG member can be kept longer than the UE of the non-CSG member in the hybrid cell.

Embodiment 20
In the above embodiment, the cell reselection method to / from the hybrid cell for keeping the CSG member UE longer than the non-CSG member UE in the hybrid cell has been disclosed. In the present embodiment, a method of handover (inbound HO / outbound HO) to / from a hybrid cell for allowing a CSG member UE to stay longer than a non-CSG member UE in the hybrid cell is disclosed.

  In handover to / from the hybrid cell, the handover procedure, rules, and criteria are made different between the non-CSG member UE and the CSG member UE. As a specific method, parameters to be applied to UEs having a CSG-ID in the whitelist or UEs registered in the CSG and parameters to be applied to UEs that are not so are provided for the parameters to be used for HO to / from the hybrid cell. . By setting the parameter to a different value between the non-CSG member UE and the CSG member UE, the criteria for handover to / from the hybrid cell are different between the non-CSG member UE and the CSG member UE. Is possible.

  As an example of parameters used for handover to / from the hybrid cell, there is a parameter serving as an index for determining whether or not to generate an event in the measurement report. Event occurrence thresholds (Thresh, Thresh1, Thresh2), serving cell offset value (Ocs) applied to the reception quality measurement result, serving cell frequency offset value (Ofs) applied to the reception quality measurement result, Neighbor cell offset value (Ocn) applied to reception quality measurement results, neighboring cell frequency offset value (Ofn), event-specific offset value (Off), event applied to reception quality measurement results There is hysteresis (Hys) etc. every time.

  For example, when the serving cell is a hybrid cell, Thresh_noncsg to be applied to a UE having a CSG-ID in the whitelist or a UE registered in the CSG and Thresh_csg to be applied to a UE that is not so are provided as the event occurrence threshold. By setting Thresh_csg higher than Thresh_noncsg, the UE of the CSG member is slower to generate an event for handover than the UE of the non-CSG member, and can remain in the hybrid cell for a long time.

  For example, regarding the offset value of the neighboring cell, Ocn_csg applied to a UE having a CSG-ID in the white list or a UE registered in the CSG, and Ocn_noncsg applied to a UE that does not. When subtracting the offset value from the reception quality measurement result, Ocn_noncsg is set higher than Ocn_csg. When the neighboring cell is a hybrid cell, the CSG member UE calculates reception quality of the neighboring cell using Ocn_csg, and the non-CSG member UE calculates reception quality of the neighboring cell using Ocn_noncsg. Since Ocn_noncsg is set higher than Ocn_csg, the UE of the CSG member generates an event for handover earlier than the UE of the non-CSG member, and can be handed over to the hybrid cell earlier.

  The parameter notification method may be individually notified to the UE to be measured from the serving cell. For example, the notification may be included in a measurement control message. As a result, each UE can be set individually, and can be set according to the radio wave condition of each UE, so that the communication quality of each UE can be improved.

  In addition, prior to measurement at the UE, a difference between a parameter applied to a UE having a CSG-ID in the white list or a UE registered in the CSG and a parameter applied to a UE that is not so is broadcast from the serving cell as broadcast information. You may make it do. Only one of the parameters may be notified to each UE individually, and the difference value may be used for deriving. As a result, the information to be notified to each UE is reduced, so that the resource load for signaling can be reduced.

  Further, the difference value may be statically determined in advance so that both the base station and the UE can recognize the information in advance. Since it is not necessary to broadcast as broadcast information, it is possible to further reduce the inability of resources for signaling.

  By using the method disclosed in the present embodiment, it becomes possible for the CSG member UE to perform HO earlier than the non-CSG member UE in the handover to the hybrid cell, and from the handover to the hybrid cell. In this handover, the UE of the CSG member can be handed over later than the UE of the non-CSG member. For this reason, it becomes possible to make CSG member UE remain in a hybrid cell longer than non-CSG member UE.

  The method disclosed in the present embodiment can be applied even when the serving cell does not recognize whether the UE is accessing as an open mode or a closed mode. The same effect can be obtained.

  The method disclosed in the present embodiment includes the fifteenth embodiment, the first modification of the fifteenth embodiment, the second modification of the fifteenth embodiment, the sixteenth embodiment, the first modification of the sixteenth embodiment, It can be used in combination with the methods disclosed in the seventeenth embodiment, the eighteenth embodiment, and the nineteenth embodiment.

  By combining the method disclosed in the present embodiment and these embodiments and modifications, the CSG can be used regardless of the UE state, that is, the UE state is not only RRC_Idle but also in the RRC_Connected state. It becomes possible to make a member UE stay in a hybrid cell longer than a non-CSG member UE.

Embodiment 21
The subject of this Embodiment is shown below. For example, the same CSG-ID cell is owned by the same owner, or the same CSG-ID cell receives the same charge preferential treatment, or the same CSG-ID cell receives the same preferential treatment at the communication speed, etc. Service is conceivable. As a result, the user may wish to reselect a cell having the same CSG-ID.

  In order to solve this problem, in this embodiment, an offset value (Qoffset_samecsg) adapted to a neighboring cell having the same CSG-ID as the serving cell, and an offset value (Qoffset_diffcsg) adapted to a neighboring cell having a CSG-ID different from the serving cell. Is provided.

  In this way, by providing an offset separately for a neighboring cell having the same CSG-ID as the serving cell and for a neighboring cell having a CSG-ID different from the serving cell, the criteria for cell reselection have the same CSG-ID. Differentiating between neighboring cells and neighboring cells having different CSG-IDs. This makes it easier to reselect a cell having the same CSG-ID than a cell having a CSG-ID different from the serving cell.

  A specific operation example will be described with reference to FIG. In FIG. 46, the description of the same step number as in FIG. 41 is omitted. In ST4103, the UE performs measurement for cell reselection and performs cell ranking. In Step ST4601, the UE judges whether or not the measured CSG-ID of the neighboring cell is the same as that of the serving cell. If it is determined that they are the same CSG-ID, the mobile terminal makes a transition to ST4602. In ST4602, the UE subtracts Qoffset_samecsg from the measured value. If a different CSG-ID is determined, the mobile terminal makes a transition to ST4603. In ST4603, the UE subtracts Qoffset_diffcsg from the measured value. By performing cell ranking based on these subtracted results, it is possible to make different judgment criteria for cell reselection between neighboring cells having the same CSG-ID and neighboring cells having different CSG-IDs. Become. It is possible to set the cell ranking to only step ST4602 or step ST4603 and omit the cell ranking in step ST4103.

  Regarding the values of Qoffset_samecsg and Qoffset_diffcsg, cells having the same CSG-ID satisfy the reselection reception quality criteria than cells having a CSG-ID different from the serving cell, depending on the radio wave environment of the serving cell and surrounding cells. It becomes easy.

  For example, the value of Qoffset_samecsg is set lower than the value of Qoffset_diffcsg (Qoffset_diffcsg> Qoffset_samecsg). By doing so, a cell having the same CSG-ID is more likely to satisfy the reselection reception quality standard than a cell having a CSG-ID different from the serving cell. By easily satisfying the reception quality standard for reselection, it becomes possible to easily reselect cells having the same CSG-ID.

  As a criteria for cell ranking, the following equation may be used.

For neighboring cells with the same CSG-ID as the serving cell,
Rn = Qmeas, n−Qoffset_samecsg
For neighboring cells that have a CSG-ID different from the serving cell,
Rn = Qmeas, n−Qoffset_diffcsg
And

  Qmeas, n is a reception quality measurement value of the nth cell, and Rn is a reception quality calculation result in consideration of an offset.

  Further, the Qoffset_samecsg and Qoffset_diffcsg may be applied only to UEs having a CSG-ID in the white list or UEs registered in the CSG. UEs that are not registered with the CSG do not want to reselect cells with the same CSG-ID. Therefore, it is possible to reduce the useless processing load of the UE that is not registered in the CSG, and to obtain the effect of reducing the power consumption of the UE.

  Alternatively, the following formula may be used as the criteria for cell ranking.

For neighboring cells with the same CSG-ID as the serving cell,
Rn = Qmeas, n−Qoffset−Qoffset_samecsg
And for neighboring cells having a CSG-ID different from the serving cell,
Rn = Qmeas, n−Qoffset−Qoffset_diffcsg
And

  Considering the conventional Qoffset, Qoffset_samecsg and Qoffset_diffcsg can be used only to make a difference depending on whether the serving cell has the same CSG-ID or a different CSG-ID from the serving cell.

  As the Qoffset_samecsg and Qoffset_diffcsg notification methods, the first to fourth methods disclosed as the cycle notification method for performing measurement for cell reselection in the fifteenth embodiment can be applied. When these are applied, the same effect can be obtained.

  In the first method, when SIB is used, notification may be performed using SIB4. In SIB4, the conventional offset value is transmitted together with the information of the corresponding cell. By transmitting the offset value together with the information, cell ranking criteria can be executed for each corresponding cell together with the conventional offset value.

  In the method disclosed above, an offset value (Qoffset_samecsg) to be applied to a neighboring cell having the same CSG-ID as the serving cell and an offset value (Qoffset_diffcsg) to be applied to a neighboring cell having a CSG-ID different from the serving cell are provided. Cell ranking is performed, and cell reselection is performed.

  As another method, a difference value (Qoffset_delta2) between an offset value applied to a neighboring cell having the same CSG-ID as the serving cell and an offset value applied to a neighboring cell having a CSG-ID different from the serving cell may be provided. . That is, Qoffset_diffcsg and Qoffset_delta2 may be provided and used for cell ranking criteria.

  For example, the following formula may be used as a criterion for cell ranking.

For neighboring cells with the same CSG-ID as the serving cell,
Rn = Qmeas, n− (Qoffset_diffcsg−Qoffset_delta2)
And for neighboring cells having a CSG-ID different from the serving cell,
Rn = Qmeas, n−Qoffset_diffcsg
And

  Thereby, an effect equivalent to the method of notifying Qoffset_samecsg and Qoffset_diffcsg disclosed above can be obtained.

  As another method, an offset value applied to a neighboring cell having a CSG-ID different from that of the serving cell may be set as a conventional Qoffset and used together with the difference value Qoffset_delta2.

  For example, the following formula may be used as a criterion for cell ranking.

For neighboring cells with the same CSG-ID as the serving cell,
Rn = Qmeas, n− (Qoffset−Qoffset_delta2)
And for neighboring cells having a CSG-ID different from the serving cell,
Rn = Qmeas, n−Qoffset
And

  Thereby, not only an effect equivalent to the method disclosed above can be obtained, but also the parameter to be set can be reduced by one. That is, it is not necessary to set both Qoffset_samecsg and Qoffset_diffcsg, and it is only necessary to set Qoffset_delta2. Therefore, it is possible to reduce the amount of information for parameter setting. The method described above can be applied as the notification method. As another method, Qoffset and Qoffset_delta2 may be notified from different cells. For example, Qoffset is notified from the serving cell, and Qoffset_delta2 is notified from the CSG cell. Since Qoffset_delta2 is a value used only for the CSG cell, the offset value (Qoffset_delta2) is set for the neighboring cell having the same CSG-ID as the serving cell in the cell ranking criteria by notifying only from the CSG cell. Recalculate using. For non-CSG cells, there is no need to recalculate, and it is only necessary to measure the reception quality. Therefore, the measurement at the time of cell reselection can be simplified, and the effect of reducing the power consumption of the UE can be obtained.

  The method disclosed in this embodiment is a method of giving Qoffset for each CSG cell shown in Non-Patent Document 11, a method of giving one Qoffset to a hybrid cell shown in Non-Patent Document 12, or a macrocell The present invention can also be applied to a method in which two Qoffsets corresponding to the RSRP range are provided and each Qoffset is applied above and below a certain threshold value of the RSRP of the macro cell. For example, these Qoffsets may be used as the Qoffset in the cell ranking criteria disclosed in the present embodiment or in addition to the Qoffset. Thereby, for example, it is possible to consider each Qoffset for each CSG cell, for each hybrid, or corresponding to the RSRP range of the macro cell.

  The method disclosed in the present embodiment includes the fifteenth embodiment, the first modification of the fifteenth embodiment, the second modification of the fifteenth embodiment, the sixteenth embodiment, the first modification of the sixteenth embodiment, The present invention can be used in combination with the methods disclosed in Embodiment 17, Embodiment 18, Embodiment 19, and Embodiment 20.

  For example, a specific operation example in combination with Embodiment 15 will be described with reference to FIG. In FIG. 47, the description of the same step number as in FIG. 42 is omitted. In Step ST4201, the UE judges whether or not the whitelist includes CSG-ID. Alternatively, the UE determines whether or not it is registered in the CSG cell. If CSG-ID is included in the white list or if it is registered in the CSG cell, ST4701 is executed. In Step ST4701, the UE subtracts Qoffset_samecsg from the measured value when the measured CSG-ID of the neighboring cell is the same as that of the serving cell. On the other hand, if the UE determines in step ST4701 that the CSG-ID is different from the serving cell, the UE subtracts Qoffset_diffcsg from the measured value. Cell ranking is performed based on the subtracted result. If the CSG-ID is not included in the white list, or if it is not registered in the CSG cell, nothing is executed in step ST4702. As a result, it is possible to make different criteria for performing cell reselection between neighboring cells having the same CSG-ID and neighboring cells having different CSG-IDs.

  Other embodiments and modifications can be used in combination by performing the same operation. By combining the method disclosed in the present embodiment with these embodiments and modifications, it is possible to obtain an effect that can flexibly cope with a difference in each radio wave environment due to flexible arrangement of HeNB or HNB.

  By adopting the method disclosed in the present embodiment, it is possible to make different criteria for performing cell reselection between neighboring cells having the same CSG-ID and neighboring cells having different CSG-IDs. This makes it easier to reselect a cell having the same CSG-ID than a cell having a CSG-ID different from the serving cell.

  As a result, the user can continuously select cells with the same CSG-ID, and can receive the same service with the same CSG-ID. Therefore, the effect of constructing a mobile communication system that is easy for the user to use can be obtained.

Embodiment 22
In order to enable CSG members to receive services such as high-speed communication and preferential billing plans for CSG members faster and longer in hybrid cells, CSG member UEs stay longer than non-CSG member UEs in hybrid cells. Is required.

  FIG. 49 shows a conceptual diagram when the CSG member UE stays longer than the non-CSG member UE in the hybrid cell. In the figure, reference numeral 4901 denotes a non-CSG cell, which is a macro cell (eNB) here. Reference numeral 4902 denotes coverage by the non-CSG cell 4901. 4903 is a hybrid access mode HeNB, that is, a hybrid cell. Reference numeral 4904 denotes coverage that can be accessed in the open access mode and the closed access mode in the hybrid cell 4903. Reference numeral 4905 denotes coverage that can be accessed only in the closed access mode in the hybrid cell 4903. 4906 is a UE of the same CSG member as the CSG to which the hybrid cell 4903 belongs. 4907 is UE of a non-CSG member. CSG member UE 4906 communicates with non-CSG cell 4901 outside the coverage 4905 area, and UE 4906 that has moved to the coverage 4905 area communicates with hybrid cell 4903 by cell reselection. The non-CSG member UE 4907 is still communicating with the non-CSG cell 4901 even in the area of the coverage 4905, and can communicate with the hybrid cell 4903 only after moving to the coverage 4904 by cell reselection.

  In this way, when cell reselection to or from a hybrid cell, if the CSG member UE stays longer than the non-CSG member UE, the coverage only in the closed access mode is wider than the coverage in the open access mode. It may become. In such a case, assuming that the initial transmission power of the UE when starting uplink communication in the hybrid cell is the same between the UE of the CSG member and the UE of the non-CSG member, the coverage that the UE of the CSG member can access is better. Therefore, there is a high possibility that the uplink transmission of the UE of the CSG member will fail at the coverage end.

  There is an RA (random access) procedure as a procedure for starting uplink communication. In the RA procedure, PRACH is used as a physical channel. A RACH preamble is used for initial transmission of the PRACH. The initial transmission power Pprach of PRACH is determined as follows (Non-patent Documents 13 and 14).

Pprach = min {Pcmax, PREAMBLE_RECEIVED_TARGET_POWER + PL} _ [dBm]
Pcmax = min {Pemax, Pumax}
Here, PREAMBLE_RECEIVED_TARGET_POWER is the target received power of the base station, PL is the path loss, Pemax is the maximum allowable power set for each cell, and Pumax is the maximum transmission power of the UE. Pemax is notified to UEs being served as broadcast information from each cell, and is the maximum allowable power common to all UEs being served. Pumax is predetermined according to the power class of each UE.

  As can be seen from the derivation formula for the initial transmission power Pprach of PRACH, for example, when PL is large, the initial transmission power is limited by Pcmax. Since Pcmax is also limited by Pemax, the initial transmission power of PRACH is limited by Pemax. Since Pemax is common to all UEs being served by the cell, the hybrid cell has the same value for both the CSG member UE and the non-CSG member UE. Therefore, when the PRACH initial transmission power is limited by Pemax, for example, when the PL is large, the CSG member UE and the non-CSG member UE can transmit only to a common Pemax. For this reason, in the hybrid cell, when the accessible coverage of the CSG member UE is wider than that of the non-CSG member UE, the uplink transmission of the CSG member UE is likely to fail. End up.

  This problem occurs in both the RRC_Idle state and the RRC_Connected state. For example, when the CSG member UE reselects a cell as a hybrid cell in the RRC_Idle state, or when the CSG member UE HOs into the hybrid cell in the RRC_Connected state. There is no prior literature on this issue and no discussion has been made in 3GPP.

  In this Embodiment, in order to eliminate this problem, the method which makes it possible to make the initial transmission power of UE when starting uplink communication differ between UE of a CSG member and UE of a non-CSG member is disclosed. As a specific example, in order to make the initial transmission power of the PRACH different between the UE of the CSG member and the UE of the non-CSG member, the maximum allowable power used when deriving the PRACH initial transmission power in the hybrid cell is defined as CSG. It is provided separately for the member UE and the non-CSG member UE. The maximum allowable power for the CSG member is Pemax_csg, and the maximum allowable power for the non-CSG member is Pemax_noncsg.

  A formula for deriving the initial transmission power Pprach in the hybrid cell is as follows.

Pprach = min {Pcmax, PREAMBLE_RECEIVED_TARGET_POWER + PL} _ [dBm]
For CSG members, Pcmax = min {Pemax_csg, Pumax}
For non-CSG members, Pcmax = min {Pemax_noncsg, Pumax}.

  By doing so, the initial transmission power Pprach in the hybrid cell can have different maximum allowable powers between the UE of the CSG member and the UE of the non-CSG member even if the PL is large. In a hybrid cell, when the coverage of a CSG member UE is wider than that of a non-CSG member UE, Pemax_csg is set larger than Pemax_noncsg, thereby reducing uplink transmission failure of the CSG member UE. It becomes possible to do.

  In addition, by providing a CSG member UE and a non-CSG member UE for the maximum allowable power for each cell, it is possible to set different initial transmission power for both UEs for each cell. It is possible to arrange a hybrid cell, and to cope with the future increase in the number of HeNBs.

  The method of deriving the uplink initial transmission power in the hybrid cell disclosed here can be applied when uplink communication is started in the hybrid cell when the CSG member UE reselects the cell to the hybrid cell in the RRC_Idle state. Further, in the state of RRC_Connected, the present invention can be applied when uplink communication is started in the hybrid cell serving as the target cell when the CSG member UE executes HO to the hybrid cell.

  A method for notifying the UE of the maximum allowable power used in the hybrid cell is disclosed below.

  As a first method, notification is made by PBCH or PDSCH using BCCH as broadcast information from a cell for setting these maximum allowable powers to UEs being served thereby. Notification is made on the PBCH using the master information (MIB) or on the PDSCH using the system information (SIB). Since the MIB is mapped to the PBCH, the method using the MIB is excellent in that the mobile terminal can receive with less control delay. When using SIB, it notifies using SIB1. The MIB or SIB1 is excellent in reducing the control delay of the mobile terminal in that it is the minimum amount of broadcast information that is received from the start of cell search to the standby state (RRC-Idle state). Is the method. Furthermore, even in the method of notifying by system information other than SIB1, since notification is made using a channel for transmitting broadcast information, it is possible to notify all mobile terminals being served thereby, and effective use of radio resources. This is an excellent method.

  As a second method, when a cell for setting these maximum permissible powers is HO as a target cell, the serving cell individually notifies the UE performing HO. Notification may be included in the information of the target cell necessary for performing HO to the UE, or may be notified using another message. Since the notification is included in the target cell information, the number of necessary messages can be reduced, so that the time until HO is completed can be reduced. On the other hand, when the notification is made using another message, the message can be notified only in the case of a cell that requires the setting of the maximum allowable power. In this case, it is possible to reduce the amount of information necessary for notification and the number of messages.

  The maximum allowable power (Pemax_csg) value for the CSG member and the maximum allowable power (Pemax_noncsg) value for the non-CSG member may be determined by the hybrid cell or by the network side (MME, HeNBGW, etc.). . When performing on the network side, the maximum allowable power is notified in advance from the network side to the hybrid cell. This notification can be performed using the hybrid cell and the interface S1 on the network side. By determining on the network side, it becomes possible to set a value based on the radio wave environment and load conditions (for example, the number of connected terminals) of the surrounding cells. As a system, it becomes possible to reduce the situation where communication is impossible, connection delay due to communication error, increase in signaling amount, concentration of load, and the like.

  In the method described above, the maximum allowable power for the CSG member is Pemax_csg, and the maximum allowable power for the non-CSG member is Pemax_noncsg. As another method, a maximum allowable power (Pemax_common) common to the CSG member and the non-CSG member may be provided, and a difference (Pemax_delta) of the maximum allowable power between the CSG member and the non-CSG member may be provided. An example of a derivation formula for the initial transmission power Pprach in the hybrid cell in this case is shown below.

Pprach = min {Pcmax, PREAMBLE_RECEIVED_TARGET_POWER + PL} _ [dBm]
For CSG members, Pcmax = min {Pemax_common + Pemax_delta, Pumax}, and for non-CSG members, Pcmax = min {Pemax_common, Pumax}. By doing in this way, it becomes possible to have different maximum permissible power between the UE of the CSG member and the UE of the non-CSG member, so that the same effect as the above-described method can be obtained.

  Note that Pemax set as the conventional maximum allowable power may be used as the common parameter Pemax_common. Thereby, it is not necessary to change the method for deriving the initial transmission power of the non-CSG member from the current method. Therefore, the effect of avoiding the complexity of the mobile communication system can be obtained.

  As another method, Pumax may be provided separately for CSG members and non-CSG members. Pumax is the maximum transmission power of the UE, and is determined in advance according to the power class of each UE. The CSG member (Pumax_csg) and non-CSG member (Pumax_noncsg) may be determined in advance according to the power class of each UE. An example of a derivation formula for the initial transmission power Pprach in the hybrid cell in this case is shown below.

Pprach = min {Pcmax, PREAMBLE_RECEIVED_TARGET_POWER + PL} _ [dBm]
For CSG members, Pcmax = min {Pemax, Pumax_csg}
For non-CSG members, Pcmax = min {Pemax, Pumax_noncsg}. In this way, Pemax can be set to be common to all UEs being served by the cell, and therefore, the same setting as the conventional setting is sufficient.

  It can also be a static value as a mobile communication system. The static value refers to a value known to a mobile terminal / base station as a mobile communication system, or a known value described in a standard document. By using a static value, no radio signal is generated between the base station (network side) and the mobile terminal. Therefore, an effect can be obtained in terms of effective use of radio resources. Furthermore, since it is a statically determined value, it is possible to obtain the effect of preventing the occurrence of radio signal reception errors.

  In the hybrid cell, a specific operation example in the case where the maximum allowable power for the CSG member is set as Pemax_csg and the maximum allowable power for the non-CSG member is set as Pemax_noncsg is shown.

  FIG. 50 shows a procedure example up to PRACH initial transmission in the hybrid cell.

  First, a CSG member UE will be described. In ST5001, a CSG member UE camps on a hybrid cell after cell reselection, for example. The hybrid cell transmits broadcast information in ST5004, and the CSG member UE receives the broadcast information. The broadcast information includes the maximum allowable power. When uplink transmission occurs in the UE of the CSG member in ST5005, the base station shifts to ST5007 and derives the uplink initial transmission power using the maximum allowable power (Pemax_csg) for the CSG member UE among the received maximum allowable power. In ST5009, the CSG member UE sets the uplink initial transmission power to the transmission power, and starts uplink transmission in ST5011.

  Next, UEs that are non-CSG members will be described. A non-CSG member UE camps on a hybrid cell, for example, after cell reselection in ST50021. The hybrid cell transmits broadcast information in ST5004, and UEs that are non-CSG members receive the broadcast information. The broadcast information includes the maximum allowable power. When uplink transmission occurs in the UE of the non-CSG member in ST5006, the base station moves to ST5008 and uses the maximum allowable power (Pemax_noncsg) for the non-CSG member UE out of the received maximum allowable power. Is derived. In ST5010, a UE that is a non-CSG member sets the uplink initial transmission power to transmission power, and starts uplink transmission in ST5012.

  In addition, since the timing of uplink transmission generation differs for each UE, the timing of uplink initial transmission also varies for each UE. Therefore, for example, as shown in the figure, ST5012 may be executed following ST5011, or conversely, ST5011 may be executed following ST5012.

  In this way, by changing the maximum allowable power used for deriving uplink initial transmission power depending on whether the UE camping on the hybrid cell is a CSG member or a non-CSG member, the UE of the CSG member can be accessed. Even when camping on a certain area, only the UE of the CSG member can increase the transmission power for uplink transmission, so that it is possible to secure sufficient uplink reception power for communication in the hybrid cell.

  With the method disclosed in the present embodiment, when the coverage of the UE of the CSG member is wider than that of the UE of the non-CSG member in the hybrid cell, the uplink transmission of the UE of the CSG member fails. It is possible to eliminate such a problem.

  In addition, it becomes possible for the CSG member UE to stay longer than the non-CSG member UE in the hybrid cell, and the CSG member provides services such as high-speed communication and preferential billing plans to the CSG member in the hybrid cell faster and longer. It is possible to receive.

  Moreover, since it becomes possible to provide the maximum allowable power lower than that of the CSG member UE for the UE of the non-CSG member, when the PL is large, the UE of the non-CSG member has an unnecessarily large transmission power. This can be prevented, and the uplink interference power can be reduced.

Embodiment 23
In the present embodiment, the initial transmission power of the UE when starting uplink communication can be made different between the UE of the CSG member and the UE of the non-CSG member, so that the CSG- The difference of the reference | standard applied to UE which has registered in UE which has ID or CSG, and UE which is not so is used.

  As a specific example, the threshold of cell reselection (S_intrasearch) disclosed in the seventeenth embodiment when the CSG-ID is not included in the white list, and the CSG-ID included in the white list or registered in the CSG And the difference from the cell reselection threshold (S_intrasearchCSG).

  As another specific example, the offset value (Qoffset_csg_in) applied to a UE having a CSG-ID in the whitelist or a UE registered in the CSG, which is disclosed in the eighteenth embodiment, and a UE that is not so. The difference of the offset value (Qoffset_noncsg_in) is used. The difference may be a difference value (Qoffset_delta).

  As another specific example, the offset value (Qoffset_csg_out) applied to the UE having the CSG-ID in the whitelist or the UE registered in the CSG disclosed in the nineteenth embodiment and the UE that is not so are applied. The difference of the offset value (Qoffset_noncsg_out) is used. The difference may be a difference value.

  These difference values may be used as a difference value between the maximum allowable power CSG member UE and the non-CSG member UE used in deriving the PRACH initial transmission power in the hybrid cell.

  Cell reselection threshold (S_intrasearch) when there is no CSG-ID in the whitelist and cell reselection threshold (S_intrasearchCSG) when there is a CSG-ID in the whitelist disclosed in the seventeenth embodiment In this case, this difference is used. Let the difference value be S_intrasearch_delta.

S_intrasearch_delta = S_intrasearch-S_intrasearchCSG
This value is defined as Pemax_delta (= Pemax_csg−Pemax_noncsg) which is a difference value between the CSG member UE and the non-CSG member UE having the maximum allowable power used in deriving the PRACH initial transmission power.

Pemax_delta = S_intrasearch_delta
Or
Pemax_delta = | S_intrasearch_delta |
It is also good.

In the case of the offset value (Qoffset_csg_in) applied to a UE having a CSG-ID in the white list or a UE registered in the CSG and the offset value (Qoffset_noncsg_in) applied to a UE that is not so disclosed in the eighteenth embodiment The difference value is Qoffset_delta (= Qoffset_noncsg_in−Qoffset_csg_in),
Pemax_delta = Qoffset_delta
Or
Pemax_delta = | Qoffset_delta |
What should I do?

In the case of the offset value (Qoffset_csg_out) applied to a UE having a CSG-ID in the whitelist or a UE registered in the CSG and the offset value (Qoffset_noncsg_out) applied to a UE not so disclosed in the nineteenth embodiment The difference value is Qoffset_delta (= Qoffset_csg_out−Qoffset_noncsg_out),
Pemax_delta = Qoffset_delta
Or
Pemax_delta = | Qoffset_delta |
What should I do?

  Specific operation of a method that uses a difference between criteria applied to a UE having a CSG-ID in a whitelist or a UE registered in the CSG and a UE not having the CSG-ID in cell reselection in derivation of the maximum allowable power in a hybrid cell An example is shown.

  FIG. 51 shows an outline of the procedure up to the PRACH initial transmission in the hybrid cell in the case of using the difference between the cell reselection thresholds.

  First, a CSG member UE will be described. In ST5101, the CSG member UE camps on cell A after cell reselection, for example. Cell A transmits broadcast information in ST5104, and the UE of the CSG member receives the broadcast information. The broadcast information includes a cell reselection threshold. In ST5105, the CSG member UE performs the cell reselection procedure using the cell reselection threshold (S_intrasearchCSG) in the received cell reselection threshold having a CSG-ID in the whitelist or registered in the CSG. . In ST5107, it is determined whether or not the cell reselection criterion is met. If it matches, the process proceeds to ST5109, and if not, the process returns to ST5105. When the CSG member UE matches the cell reselection criteria in ST5107 and reselects the hybrid cell, the UE camps on the hybrid cell in ST5109.

  The hybrid cell transmits broadcast information in ST5112, and the CSG member UE receives the broadcast information. The broadcast information includes the maximum allowable power. However, the maximum allowable transmission power broadcast here does not include the maximum allowable transmission power set differently for the CSG member and the non-CSG member as disclosed in Embodiment 22, and is common to the conventional cells. Only the maximum allowable power. When uplink transmission occurs in the UE of the CSG member in ST5113, the mobile station moves to ST5115 and receives the threshold for cell reselection (S_intrasearch) in the case of having no CSG-ID in the whitelist received in ST5104, and the whitelist A difference value (S_intrasearch_delta) of a cell reselection threshold (S_intrasearchCSG) in the case of having a CSG-ID therein is derived. In ST5116, the CSG member UE sets the difference value (S_intrasearch_delta) as the transmission power difference (Pemax_delta) between the CSG member UE and the non-CSG member UE, and uses the difference value (Pemax_delta) in ST5117. An initial transmission power (Pprach) is derived. In ST5119, the CSG member UE sets the uplink initial transmission power to the transmission power, and starts uplink transmission in ST5121.

  Next, UEs that are non-CSG members will be described. Here, the non-CSG member UE camps on cell A after ST cell reselection, for example, in ST5102. Cell A is transmitting broadcast information in ST5104, and UEs that are non-CSG members receive the broadcast information. The broadcast information includes a cell reselection threshold. In ST5106, the non-CSG member UE performs the cell reselection procedure using the cell reselection threshold (S_intrasearch) when the CSG-ID is not included in the whitelist among the received cell reselection thresholds. In ST5108, it is determined whether or not the cell reselection criterion is met. If the cell reselection criterion is met, the process proceeds to ST5110, and if not, the process returns to ST5106. When the non-CSG member UE meets the cell reselection criteria in ST5108 and reselects the hybrid cell, the UE camps on the hybrid cell in ST5110.

  In the case of a UE that has a CSG-ID in the white list but is a non-CSG member of the hybrid cell, the hybrid cell must be reselected in the open access mode. A cell reselection procedure is performed using a threshold value (S_intrasearch) for cell reselection when no ID is provided, and it is determined whether or not the cell reselection criteria are met. In the case of a UE that has a CSG-ID in the white list but is a non-CSG member of a hybrid cell, for example, even if the UE performs the cell reselection procedure using S_intrasearchCSG first, the UE will change the CSG-ID of the cell. The received CSG-ID is checked, and if the CSG-ID does not match, cell reselection may be performed using the cell reselection procedure ST5106 for non-CSG members.

  The hybrid cell transmits broadcast information in ST5112, and UEs that are non-CSG members receive the broadcast information. The broadcast information includes the maximum allowable power. However, the maximum allowable transmission power broadcast here does not include the maximum allowable transmission power set differently for the CSG member and the non-CSG member as disclosed in Embodiment 22, and is common to the conventional cells. Only the maximum allowable power. When uplink transmission occurs in the CSG member UE in ST5114, the UE moves to ST5118, and the uplink initial transmission power in ST5118 using the maximum allowable power (Pemax_common) common in the conventional cell broadcast from the hybrid cell in ST5112. (Pprach) is derived. In ST5120, the non-CSG member UE sets the uplink initial transmission power to the transmission power, and starts uplink transmission in ST5122.

  In addition, since the timing of uplink transmission generation differs for each UE, the timing of uplink initial transmission also varies for each UE. For this reason, for example, as shown in the figure, ST5122 may be executed following ST5121, or conversely, ST5121 may be executed following ST5122.

  In this way, a UE that is camping on a hybrid cell using a difference between a UE having a CSG-ID in the whitelist or a UE registered in the CSG and a UE that is not so in cell reselection. Depending on whether is a CSG member or a non-CSG member, it is possible to adopt a method in which the maximum allowable power used for deriving uplink initial transmission power is different. At this time, even if the CSG member UE is camping on an accessible area, only the CSG member UE can increase the transmission power of uplink transmission, which is sufficient for communication in the hybrid cell. It is possible to secure uplink reception power.

  The method disclosed in the seventeenth embodiment, the eighteenth embodiment, the nineteenth embodiment, and the twentieth embodiment is not limited to the above specific example.

  Not limited to this example, among the criteria in cell reselection, the PRACH initial for the CSG member UE and the non-CSG member UE is set based on the difference between the configuration parameters that affect the coverage of the hybrid cell. What is necessary is just to derive each transmission power.

  In addition, when a plurality of criteria for cell reselection (for example, a threshold value and offset for cell reselection) are set, it is preferable to determine in advance which criterion is used. For example, a priority may be given to which one of a plurality of criteria is used. In this way, even if any criterion is not set, it is possible to use other criteria in order of priority. As another example, it may be determined which criterion is used according to the difference value among a plurality of criteria. For example, a reference having the largest difference value is used. As yet another example, an average value of a plurality of reference difference values may be used.

  As another method, the serving cell may determine which criterion to use from among a plurality of criteria and notify the UE. As a notification method, you may make it notify as alerting | reporting information. Instead of determining the serving cell, the network side (MME, HeNBGW, etc.) may determine and notify the UE via the serving cell. The interface S1 can be used for notification from the network side to the serving cell. By doing so, it becomes possible to flexibly cope with the arrangement of cells including the hybrid cell. When the network side decides, it becomes possible to set a value based on the radio wave environment and load conditions (for example, the number of connected terminals) of the surrounding cells. As a system, it becomes possible to reduce the situation where communication is impossible, connection delay due to communication error, increase in signaling amount, concentration of load, and the like.

  The method described above uses the criteria for cell reselection. Therefore, it can be used when the hybrid cell is reselected using the reference. In other cases, for example, when moving to a hybrid cell by HO, the method disclosed in Embodiment 22 can be applied, and the setting value can be individually notified from the serving cell to the UE performing HO. It ’s fine.

  In the hybrid cell, by using the method disclosed in the present embodiment, the initial transmission power of the UE when starting uplink communication can be made different between the UE of the CSG member and the UE of the non-CSG member. It is possible for a CSG member UE to stay longer than a non-CSG member UE.

  In addition, in order to make it possible to make the initial transmission power of the UE when starting uplink communication different between the UE of the CSG member and the UE of the non-CSG member, it is used for deriving the PRACH initial transmission power in the hybrid cell. The maximum allowable power is provided separately for the UE of the CSG member and for the UE of the non-CSG member, and these are broadcast from the hybrid cell to the UEs being served thereby. However, the PRACH initial transmission power is derived in the hybrid cell. It is not necessary to separately provide the maximum allowable power used for the UE of the CSG member and the UE of the non-CSG member, and therefore it is not necessary to notify them to the UEs being served thereby. Therefore, it is possible to reduce the number of parameters that need to be broadcast in the hybrid cell and further reduce the amount of information to be signaled.

  The method disclosed in the seventeenth to twenty-third embodiments is not limited to the case where open mode cells (non-CSG cells) and CSG cells are mixed in the same frequency carrier (same frequency layer) (mixed carrier), The present invention can also be applied to the case where only the CSG cell is present in the same frequency carrier (same frequency layer) (dedicated carrier). Further, if there is a hybrid cell in the same frequency layer, it can be applied.

  Further, the present invention can be applied not only to cell reselection and HO within the same frequency layer (intra-frequency), but also between frequency layers (inter-frequency) or between systems (RAT) (inter-RAT).

  In the above, LTE using HeNB using CSG has been described, but the present invention is UMTS using HNB using CSG, and HeNB, HNB not using CSG, and a base station with a small radius (also called a pico cell or macro cell). ) Is also applicable. In the first modification of the sixteenth embodiment, the following effects can be obtained in addition to the effects of the sixteenth embodiment. It is possible to reduce the power consumption of the mobile terminal when it is not registered in the CSG cell existing around the current serving cell. Furthermore, the network side (base station or the like) has the above effect without knowing which CSG cell the corresponding mobile terminal is registered in (which CSG-ID is in the white list). The solution of the first modification of the sixteenth embodiment is excellent. Thereby, it is not necessary to notify the CSG-ID in the white list from the mobile terminal to the base station, and radio resources can be effectively used. In addition, it is possible to obtain an effect of reducing the processing load of the base station in that the base station does not need to manage the CSG-ID in the white list of the mobile terminal being served.

  In the above description, the case where the CSG-ID, which is information broadcasted by the CSG cell or cell, and the tracking area code (TAC) broadcasted by the CSG cell or cell are mainly described. Even when the CSG-ID and the TAC are not associated with each other, it is of course applicable.

  If they are not associated with each other, for example, it may be determined separately whether or not they have already been registered in the CSG and whether or not TA update is necessary.

  When determining whether or not the mobile terminal has already been registered in the cell selected by the cell reselection, whether or not the CSG-ID received by the broadcast information of the cell exists in the white list of the mobile terminal Judge with. When the CSG-ID received by the broadcast information of the cell exists in the white list, it is determined that the mobile terminal has already been registered in the selected cell. That is, it is determined that the cell can be an “appropriate cell” for the mobile terminal. On the other hand, when the CSG-ID received by the broadcast information of the cell does not exist in the white list of the mobile terminal, it is determined that the mobile terminal is not registered in the selected cell. That is, it is determined that the cell cannot be an “appropriate cell” for the mobile terminal.

  When it is determined whether or not TA update is necessary at the time of cell reselection, one or a plurality of TACs (hereinafter referred to as TA list) stored in the mobile terminal of the TAC received by the broadcast information of the cell. Judgment is made based on whether or not it is included. When the TAC received by the broadcast information of the cell is included in the TA list in the own mobile terminal, it is determined that the TA update is unnecessary and the TAU is unnecessary. On the other hand, when the TAC received by the broadcast information of the cell is not included in the TA list in the own mobile terminal, it is determined that TA update is necessary and TAU needs to be performed.

  Specific examples correspond to step ST1406 to step ST1409 in FIG. 14, step ST1607 to step ST1610 in FIG.

  Although the present invention has been described centering on the LTE system (E-UTRAN), it is applicable to the W-CDMA system (UTRAN, UMTS) and LTE-Advanced. Furthermore, the present invention can be applied to a mobile communication system in which a CSG (Closed Subscriber Group) is introduced and a communication system in which an operator specifies a subscriber and the specified subscriber is allowed to access in the same manner as the CSG. It is.

  101 mobile terminal, 102 base station, 103 MME (Mobility Management Entity), 104 S-GW (Serving Gateway).

Claims (5)

A mobile communication system including a mobile terminal and a base station that performs wireless communication with the mobile terminal,
Informing the mobile terminal of the range of identification codes (CSG-ID) assigned to the cell (CSG cell) to which the identified subscriber is permitted to access ;
The range of the identification code (CSG-ID) is a range of CSG-IDs related to other frequency layers different from the frequency layer to which the CSG cell belongs.
A mobile communication system.   The mobile communication system according to claim 1, wherein the identification code (CSG-ID) is a physical cell identity (PCI).   The mobile communication system according to claim 1, wherein the range of the identification code (CSG-ID) is notified using a control channel (DCCH) individually set for each mobile terminal. A base station that performs wireless communication with a mobile terminal,
Notifying the mobile terminal of a range of identification codes (CSG-ID) assigned to the cell (CSG cell) to which the identified subscriber is allowed access ,
The range of the identification code (CSG-ID) is a range of CSG-IDs related to other frequency layers different from the frequency layer to which the CSG cell belongs.
A base station characterized by that. A mobile terminal that performs wireless communication with a base station,
Receiving from the base station a range of identification codes (CSG-ID) assigned to cells (CSG cells) to which the identified subscribers are allowed access ;
The range of the identification code (CSG-ID) is a range of CSG-IDs related to other frequency layers different from the frequency layer to which the CSG cell belongs.
A mobile terminal characterized by that.

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