JP3936353B2 - Communication control apparatus and mobile communication method - Google Patents

Description

  The present invention relates to a communication control device and a mobile communication method.

  Methods for managing the location of mobile devices and subscriber information in a mobile communication system include an HLR (Home Location Register) method and a VLR (Visitor Location Register) method. The HLR method is a method of managing location information and subscriber information of a mobile device in an HLR independent of the exchange. The VLR method is a method of downloading subscriber information to a VLR for each exchange (Mobile Switching Center, hereinafter referred to as “MSC”), and managing the location information and subscriber information of the mobile device in response to location registration. The PLR (Personal Digital Cellular) system employs the HLR system, and the UMTS (Universal Mobile Telecommunications System) employs the VLR system (see, for example, Non-Patent Document 1).

  In the VLR scheme, the MSC may receive location registration requests from a number of mobile devices that exceed the capacity that the VLR included in the MSC can accommodate subscriber information. As a response to the location registration request exceeding the capacity, a method of securing a free capacity by deleting a part of the subscriber information already held by the VLR, or storing the subscriber information in another VLR, MSC has a method of holding information for identifying a storage destination VLR (see, for example, Patent Document 1).

  In the VLR method, a distributed processing method called an Iu-Flex method has been proposed (see, for example, Non-Patent Document 2). Specifically, as shown in FIG. 16, at the time of location registration, an RNC (Radio Network Controller) 320 manages an MSC that processes a location registration signal 301a from the mobile device 310, and manages an area where the mobile device 310 is located. A plurality of MSCs 330a to 330c are selected. The subscriber information 301c is downloaded from the HLR 350 to the VLR 340b included in the selected MSC 330b. The MSC 330b transmits a location registration completion signal 301e including the MSC identifier (MSC2) of the MSC 330b to the RNC 320. The RNC 320 transmits a location registration completion signal 301e to the mobile device 310.

After the location registration, as shown in FIG. 17, the mobile device 310 transmits a service request signal 301f including the MSC identifier (MSC2) notified at the time of location registration. As a result, the mobile device 310 can use the MSC 330b whose location is registered. As described above, by providing a plurality of VLRs in one area, the mobile communication system can perform location registration of many mobile devices.
3GPP Recommendation, TS. 23.002, “Network Architecture” 3GPP Recommendation, TS. 23.236, “Intra-domain connection of Radio Access Network (RAN) nodes to multiple Core Network (CN) nodes” JP 2002-320032 A

  However, even when the Iu-Flex method is adopted and a plurality of VLRs are provided in one area, there is a possibility that the capacity of the VLR may be used up if the number of mobile devices that perform location registration increases.

  At this time, if the location registration is rejected, the mobile communication service cannot be provided to the mobile device. In addition, when the conventional response method when the VLR capacity is insufficient is applied, the location registration can be performed, but the following problems occur at the time of outgoing / incoming calls after location registration.

  In the method for deleting the subscriber information, as shown in FIG. 18, when the service request signal 301f including the MSC identifier (MSC2) is transmitted from the mobile device 310 that has deleted the subscriber information from the VLR 340b, the MSC 330b Subscriber information needs to be obtained from the HLR 350. As a result, connection delay, signal amount, and processing load may increase.

  In the method of storing the subscriber information in another VLR, as shown in FIG. 19, in the MSC 330b storing the subscriber information in the VLR 340a, the mobile device 310 and the VLR 340a of the storage destination are associated with each other and stored in the own VLR 340b. It is necessary to keep it. That is, the MSC 330b needs to store the identifier “MS1” of the mobile device 310 and the identifier “VLR1” of the VLR 340a in association with its own VLR 340b.

Therefore, the capacity of the VLR 340b is consumed for purposes other than holding subscriber information. Further, when the service request signal 301f is transmitted from the mobile device 310, it is necessary to transfer the subscriber information between the MSC 330a and VLR 340a that are the storage destinations and the MSC 330b and VLR 340b that process the service request signal 301f. As a result, this method also
There is a risk of increasing connection delay, signal amount, and processing load.

  Therefore, an object of the present invention is to provide a mobile communication service to more mobile devices and prevent an increase in connection delay and signal amount at the time of outgoing / incoming calls.

  One feature of the present invention is a communication system comprising a plurality of exchanges and a plurality of area subscriber information holding means respectively corresponding to the plurality of exchanges, and a mobile station addressed to one of the plurality of exchanges. The communication control device for processing the location registration signal transmitted by the mobile station according to the available capacity of one area subscriber information holding means corresponding to the one exchange among the plurality of area subscriber information holding means. A transfer means for transferring the location registration signal to another exchange, and a notification for notifying the mobile station of the other exchange when the location of the mobile station is registered by the other exchange. And a service request signal for requesting service provision is transmitted from the mobile station to the other exchange.

  According to such a communication control device, even when the area subscriber information holding means of a certain exchange has a small free space, the position registration signal can be transferred to another exchange and the position of the mobile station can be registered. it can. In addition, the communication control apparatus can notify the mobile station of the transfer destination exchange that has performed location registration. Therefore, after the location registration, the mobile device can perform location registration and transmit a signal to the transfer destination exchange that holds the subscriber information of the mobile device in the area subscriber information holding means. Therefore, the communication control apparatus can provide mobile communication services to more mobile devices, and can prevent an increase in connection delay and signal amount at the time of outgoing / incoming calls.

  One feature of the present invention is that, in the one feature described above, the transfer means determines whether or not to transfer the location registration signal based on a transfer history of the location registration signal.

  One feature of the present invention is that, in the one feature described above, the transfer means transfers the transfer history together with the location registration signal to the other exchange.

  One feature of the present invention is that, in the one feature described above, the transfer means includes a capacity management device that manages the free capacity of the plurality of area subscriber information holding means, and the one of the area subscriber information holding means. The main point is to acquire the free space.

  One feature of the present invention is that, in the one feature described above, the communication control device is a wireless control device connected to the plurality of exchanges or the exchange.

  One feature of the present invention is a communication system comprising a plurality of exchanges and a plurality of area subscriber information holding means respectively corresponding to the plurality of exchanges, and a mobile station addressed to one of the plurality of exchanges. The mobile communication method for processing the location registration signal transmitted by the mobile station is based on the free capacity of one area subscriber information holding means corresponding to the one exchange among the plurality of area subscriber information holding means. A step of transferring the location registration signal to another exchange, and a step of notifying the mobile station of the other exchange when the location registration of the mobile station is performed by the other exchange. The service request signal for requesting the provision of the service is transmitted from the mobile station to the other exchange.

  As described above, according to the present invention, mobile communication services can be provided to more mobile devices, and connection delay and signal amount increase at the time of outgoing / incoming calls can be prevented.

[First Embodiment]
(Mobile communication system)
As shown in FIG. 1, a mobile communication system 100 includes a mobile device 10, an RNC (Radio Network Controller) 20, a plurality of MSCs (Mobile Switching Center) 30a, 30b, 30c, and a plurality of VLRs (Visitor Location Registers). 40a, 40b, 40c and an HLR (Home Location Register) 50.

  The mobile communication system 100 employs a VLR system and employs a distributed processing system called an Iu-Flex system. Specifically, in the mobile communication system 100, a plurality of MSCs 30a to 30c manage one area, and for each MSC 30a to 30c, a VLR 40a that holds subscriber information of the mobile device 10 located in the area managed by the MSC 30a to 30c. ˜40c. Therefore, in the mobile communication system 100, load distribution of the VLRs 40a to 40c corresponding to the MSCs 30a to 30c can be achieved.

  The MSCs 30a to 30c are exchanges that perform location registration processing and call processing. The MSCs 30a, 30b, and 30c include VLRs 40a, 40b, and 40c, respectively. Each of the VLRs 40a, 40b, and 40c is an area subscriber information holding unit that holds subscriber information of the mobile device 10 located in an area managed by the corresponding MSC 30a, 30b, or 30c.

  The RNC 20 is a radio control device that controls radio communication between the mobile device 10 and the base station. The RNC 20 transmits and receives signals to and from the mobile device 10 via the base station. The HLR 50 holds subscriber information of the entire mobile communication system 100 and provides it to the MSCs 30a to 30c.

  In the mobile communication system 100, the MSCs 30a to 30c function as communication control devices that transfer location registration signals, and transfer location registration signals between the MSCs 30a to 30c based on the VLR free capacity. That is, when the VLR capacity is insufficient, the MSC that has received the location registration signal from the RNC distributes the processing of the location registration signal to other MSCs. “MSC1”, “MSC2”, and “MSC3” are assigned to the MSCs 30a, 30b, and 30c as MSC identifiers for identifying the MSCs.

  Next, the configuration of the MSCs 30a to 30c and the VLRs 40a to 40c will be described with reference to FIG. The MSC 30 a includes a transfer unit 31, a VLR management unit 32, a control unit 33, and a signal transmission / reception unit 34. The VLR 40 a includes a subscriber information management unit 41 and a subscriber information memory 42. The MSCs 30b and 30c and the VLRs 40b and 40c have the same configuration as the MSC 30a and the VLR 40a.

  The VLR 40a may be provided inside the MSC 30a or may be provided outside the MSC 30a. FIG. 2 shows a case where the MSC 30a includes the VLR 40a outside the MSC 30a. The signal transmission / reception unit 34 transmits / receives signals to / from the HLR 50, RNC 20, and other MSCs 30b, 30c. The VLR management unit 32 manages the VLR 40a. Specifically, the VLR management unit 32 stores subscriber information in the VLR 40a, deletes subscriber information from the VLR 40a, acquires subscriber information from the VLR 40a at the time of outgoing / incoming calls, etc. Is detected.

  The transfer unit 31 is a transfer unit that transfers a location registration signal from the mobile device 10 to a transfer destination exchange (hereinafter referred to as “transfer destination MSC”) according to the free capacity of the VLR 40a. The transfer unit 31 determines whether or not the position registration signal can be transferred, and selects a transfer destination MSC. The control unit 33 performs various processes. In particular, the control unit 33 performs processing related to location registration. The control unit 33 also functions as a notification unit that notifies the mobile device 10 of the transfer destination MSC for which location registration has been performed.

  The subscriber information memory 42 holds subscriber information of the mobile device 10 whose location is registered in the MSC 30a. The subscriber information management unit 41 acquires subscriber information stored in the VLR 40a from the MSC 30a and stores it in the subscriber information memory 42. The subscriber information management unit 41 deletes the subscriber information from the subscriber information memory 42 according to the instruction of the MSC 30a, acquires the subscriber information from the subscriber information memory 42, and provides it to the MSC 30a. 42 detects the free capacity of 42 and notifies the MSC 30a.

  Next, specific processing at the time of location registration and outgoing / incoming calls will be described. First, the process at the time of location registration will be described with reference to FIG. For example, the mobile device 10 performs position registration at the time of activation, change of a service area, or periodically. The mobile device 10 transmits a location registration signal 1a to the RNC 20 via the base station. The RNC 20 that has received the location registration signal 1a selects one MSC 30a from the MSCs 30a to 30c that manage the area where the mobile device 10 is located. The RNC 20 transfers the location registration signal 1a to the selected MSC 30a. Thus, the mobile device 10 can transmit the location registration signal 1a to any MSC via the RNC 20.

  The signal transmission / reception unit 34 of the MSC 30a receives the location registration signal 1a. The VLR management unit 32 detects the free capacity of the VLR 40a. The transfer unit 31 determines whether the location registration signal 1a is processed in the MSC 30a or transferred to another MSC based on the free space of the VLR 40a. For example, the transfer unit 31 can determine by determining a free capacity threshold value for determining whether transfer is possible and comparing the detected free capacity with the threshold value.

  If the VLR 40a has insufficient free space and determines that the location registration signal 1a is to be transferred, the transfer unit 31 selects the transfer destination MSC from the MSCs 30b and 30c that manage the same area. The transfer unit 31 transfers the location registration signal 1a to the MSC 30b selected as the transfer destination MSC. Specifically, the transfer unit 31 generates a location registration transfer signal 1b including the location registration signal 1a from the mobile device 10 and transfers it to the MSC 30b via the signal transmission / reception unit 34.

  The signal transmission / reception unit 34 of the MSC 30b receives the location registration transfer signal 1b. The transfer unit 31 of the MSC 30b detects the free capacity of the VLR 40b in the same manner as the MSC 30a. If the free space is insufficient, the MSC 30b also transfers the location registration transfer signal 1b to the MSC 30c in the same manner as the MSC 30a.

The MSC 30c that has received the location registration transfer signal 1b detects the free space of the VLR 40c in the same manner as the MSC 30a. When the free space of the VLR 40c is sufficient for location registration, the transfer unit 31 of the MSC 30c instructs the location registration process to the control unit 33, and the control unit 33 performs the location registration process.

  Specifically, the control unit 33 transfers the location registration signal 1 a to the HLR 50 via the signal transmission / reception unit 34. The HLR 50 transmits to the MSC 30c the subscriber information 1c of the mobile device 10 whose location is registered, and downloads it. The VLR management unit 32 acquires the subscriber information 1c via the signal transmission / reception unit 34 and stores it in the VLR 30c. After completion of storage, the VLR management unit 32 transmits a storage completion signal to the HLR 50 via the signal transmission / reception unit 34. When the HLR 50 receives the storage completion signal, the HLR 50 updates the location registration destination MSC of the mobile device 10 to the MSC 30c. The HLR 50 transmits a registration completion signal to the MSC 30c.

  After the location registration process is completed, the control unit 33 generates a location registration completion transfer signal 1d for notifying the transfer source exchange (hereinafter referred to as “transfer source MSC”) of the completion of location registration. The control unit 33 generates a location registration completion transfer signal 1d in which the MSC identifier “MSC3” of the MSC 30c itself that has performed the location registration process is set. The control unit 33 transfers the generated location registration completion transfer signal 1 d via the signal transmission / reception unit 34. The location registration completion transfer signal 1d follows the transfer path of the location registration signal 1a, and is transferred to the MSC 30a that is the transfer source MSC via the MSC 30b.

  The control unit 33 of the MSC 30a that has received the location registration completion transfer signal 1d receives the location registration completion signal 1e in which the MSC identifier “MSC3” of the transfer destination MSC that has performed location registration is set in the location registration completion transfer signal 1d. Generate. The control unit 33 transmits the generated location registration completion signal 1e to the RNC 20 via the signal transmission / reception unit 34. The RNC 20 transmits the received location registration completion signal 1 e to the mobile device 10. As described above, the MSC 30a of the transfer source MSC transmits the position registration completion signal 1e in which the MSC identifier “MSC3” of the transfer destination MSC that has performed the position registration is set to the mobile device 10 via the RNC 20, and performs the position registration. The mobile station 10 is notified of the implemented transfer destination MSC.

  The mobile device 10 that has received the location registration completion signal 1e stores the MSC identifier “MSC3” included in the location registration completion signal 1e. The MSC 30c is used for outgoing / incoming calls after location registration. When the transfer unit 31 of the MSC 30a determines that the VLR 40a has enough free space and the location registration signal 1a is to be processed by the MSC 30a, the transfer unit 31 instructs the control unit 33 to process the location registration signal 1a. The control unit 33 performs normal location registration processing based on the location registration signal 1a.

  Next, processing at the time of outgoing / incoming calls will be described with reference to FIG. The mobile device 10 transmits a service request signal 1f to the RNC 20 when making / receiving a call. At this time, the mobile device 10 sets the MSC identifier “MSC3” acquired during the location registration process in the service request signal 1f. The RNC 20 that has received the service request signal 1f determines the signal transmission destination to be the MSC 30c based on the MSC identifier “MSC3”, and transmits the service request signal 1f to the MSC 30c. In this way, the mobile device 10 can transfer the service request signal to the MSC 30c holding the subscriber information via the RNC 20. The MSC 30c that has received the service request signal 1f performs processing using the subscriber information held by its own VLR 40c.

  Thus, at the time of outgoing / incoming call, access to the MSC 30a, 30b via the location registration signal 1a does not occur during location registration. That is, the process is the same as that performed when direct location registration is performed in the MSC 30c. The MSC 30c does not need to acquire subscriber information from the other VLRs 40a and 40b and the HLR 50. As a result, an increase in connection delay and signal amount can be prevented, and the processing load can be reduced.

  Next, the determination of whether or not the location registration signal can be transferred and the selection of the transfer destination MSC will be described in more detail with reference to FIGS. The transfer unit 31 can determine whether or not the position registration signal can be transferred based on the transfer history of the position registration signal. The transfer history includes, for example, the number of times the position registration signal is transferred, the MSC to which the position registration signal has been transferred, and the like.

  When the number of transfers is used, the transfer unit 31 adds the number of transfers as a transfer history to the position registration signal and transfers it. Specifically, the transfer unit 31 generates a location registration transfer signal that includes the location registration signal and sets the number of transfers. Each time the transfer unit 31 of each MSC transfers the location registration signal, the transfer count increases. That is, the counter value of the number of transfers is incremented by 1 for each transfer.

  If the VLR has insufficient free space, the transfer unit 31 determines whether to perform transfer based on the number of transfers. For example, the transfer unit 31 can determine the threshold value of the transfer count for determining whether transfer is possible or not by comparing the threshold value with the transfer count included in the location registration transfer signal. As the threshold value for the number of transfers, for example, a value obtained by subtracting 1 from the number of MSCs managing the same area can be set.

  When the number of transfers reaches the threshold, the transfer unit 31 determines that transfer is not performed and stops the transfer. According to this, when the capacity of the VLR of any of the plurality of MSCs managing the same area is insufficient, it is possible to prevent a loop in which the transfer destination MSC is obtained and the transfer is repeated many times.

  FIG. 4 shows a specific example in which transfer is limited by the number of transfers. The threshold value for the number of transfers is set to “2” obtained by subtracting “1” from the number “3” of the MSCs 30 a to 30 c managing the same area. The transfer unit 31 of the MSC 30a that has received the location registration signal 1a from the mobile device 10 via the RNC 20 transfers the location registration signal to another MSC 30b because the capacity of the VLR 40a is insufficient. The transfer unit 31 can freely select a transfer destination MSC. At this time, the transfer unit 31 generates and transfers a location registration transfer signal (a) 101b including the location registration signal 1a and set the number of transfers “1”.

  When the MSC 30b that has received the location registration transfer signal (a) 101b also has insufficient free space in the VLR 40b, the transfer unit 31 of the MSC 30b uses the transfer count “1” set in the location registration transfer signal (a) 101b and a threshold value. Compare with “2”. The transfer unit 31 determines to transfer because the transfer count is less than the threshold. The transfer unit 31 selects an MSC 30c other than the MSC 30a that is the transfer source MSC as the transfer destination MSC. The transfer unit 31 adds 1 to the number of transfers “1” set in the position registration transfer signal (a) 101b to generate and transfer a position registration transfer signal (b) 201b in which the number of transfers “2” is set.

  When the MSC 30c that has received the location registration transfer signal (b) 201b also has insufficient free space in the VLR 40c, the transfer unit 31 of the MSC 30c sets the transfer count “2” set in the location registration transfer signal (b) 201b and the threshold value. Compare with “2”. The transfer unit 31 stops the transfer because the transfer count has reached the threshold value. In this case, the transfer unit 31 instructs the control unit 33 to reject the location registration process.

  The control unit 33 generates a location registration rejection transfer signal 1g for notifying the transfer source MSC of rejection of the location registration process. The control unit 33 transfers the generated location registration rejection transfer signal 1 g via the signal transmission / reception unit 34. The location registration rejection transfer signal 1g follows the transfer path of the location registration signal 1a, and is transferred to the MSC 30a that is the transfer source MSC via the MSC 30b.

  Upon receiving the location registration rejection transfer signal 1g, the control unit 33 of the MSC 30a generates a location registration rejection signal 1h that notifies the mobile device 10 that subscriber information cannot be registered in the VLR and location registration is rejected. The control unit 33 transmits the generated location registration rejection signal 1h to the RNC 20 via the signal transmission / reception unit 34. The RNC 20 transmits the received location registration rejection signal 1 h to the mobile device 10.

  Further, when using information on the MSC to which the location registration signal has been transferred (hereinafter referred to as “transfer completed information”), the transfer unit 31 adds the transferred information to the location registration signal as a transfer history and transfers it. Specifically, the transfer unit 31 includes a location registration signal and generates a location registration transfer signal in which the transferred information is set. Each time the transfer unit 31 of each MSC transfers the location registration signal, it records the transferred information.

  When selecting the transfer destination MSC, the transfer unit 31 refers to the transferred information, excludes the transferred MSC, and selects the transfer destination MSC. As described above, the transfer unit 31 records the transferred information in the position registration signal to be transferred, and determines the transfer destination MSC based on the transferred information, thereby avoiding repeatedly selecting the same MSC. To do. In particular, when the VLR capacity of any of a plurality of MSCs managing the same area is insufficient, it is possible to prevent a loop in which a transfer destination MSC is obtained and transfer is repeated many times.

  FIG. 5 shows a specific example of selecting the transfer destination MSC based on the transferred information. The transfer unit 31 of the MSC 30a that has received the location registration signal 1a from the mobile device 10 via the RNC 20 transfers the location registration signal to another MSC 30b because the capacity of the VLR 40a is insufficient. The transfer unit 31 can freely select a transfer destination MSC. At this time, the transfer unit 31 generates and transfers a location registration transfer signal (c) 301b that includes the location registration signal 1a and sets “MSC1” of the MSC 30a itself as the MSC identifier of the transferred MSC.

  When the MSC 30b that has received the location registration transfer signal (c) 301b also has insufficient free space in the VLR 40b, the transfer unit 31 of the MSC 30b sets the transferred MSC “MSC1” set in the location registration transfer signal (c) 301b. Based on this, the MSC 30c other than the MSC 30a indicated by “MSC1” is selected as the transfer destination MSC.

  The transfer unit 31 generates and transfers a location registration transfer signal (d) 401b in which “MSC2” of the MSC 30b itself is set in addition to the transferred MSC “MSC1” set in the location registration transfer signal (c) 301b.

  The MSC 30c that has received the location registration transfer signal (d) 401b performs location registration processing in the same manner as in FIG. 1 when the free space of the VLR 40c is sufficient, and transfers the location registration completion transfer signal 1d to the MSC 30a that is the source MSC. To do.

  When the transfer history is used as shown in FIGS. 4 and 5, the MSCs 30 b and 30 c indicate that the transfer history indicates that there is no free space in any of the VLRs 40 a to 40 c (for example, when the number of transfers is large, the transfer has been completed. For example, when there is no MSC other than the MSC), the location registration signal can be transferred according to the situation of the plurality of VLRs 40a to 40c. In addition, the transfer unit 31 can add the transfer history such as the transfer count and the transferred information to the position registration signal 1a and transfer it. Therefore, the MSCs 30b and 30c can easily determine whether or not the location registration signal 1a can be transferred using the transfer history added to the location registration signal 1a.

  Further, as shown in FIG. 6, the mobile communication system 100 may be provided with a VLR capacity management database 60 and used for selection of the transfer destination MSC. The VLR capacity management database 60 is a capacity management apparatus that holds the free capacity of a plurality of area subscriber information holding means. The VLR capacity management database 60 stores a VLR identifier for identifying a VLR assigned to the VLRs 40a to 40c and a free capacity in association with each other. VLR identifiers “VLR1”, “VLR2”, and “VLR3” are assigned to the VLRs 40a, 40b, and 40c, respectively.

  The VLR capacity management database 60 periodically acquires and holds free capacity from the MSCs 30a to 30c. In this case, the VLR management unit 32 of each of the MSCs 30a to 30c periodically notifies the VLR capacity management database 60 of the free capacity of its own VLR 40a to 40c via the transmission / reception unit 34. The VLR capacity management database 60 may be installed in any location of the mobile communication system 100, may be provided in any MSC or HLR 50, or may be provided outside the MSC or HLR 50.

  When selecting the transfer destination MSC, the transfer unit 31 acquires the free capacity from the VLR capacity management database 60, selects the transfer destination MSC based on the acquired free capacity, and transfers the location registration signal. Specifically, the transfer unit 31 inquires of the VLR capacity management database 60 about the free capacity of another MSC, and selects an MSC having a free capacity capable of location registration as the transfer destination MSC. According to this, the MSC 30a can easily acquire the free capacity of the plurality of VLRs 40b and 40c, and can appropriately select the transfer destination MSC based on the free capacity of the plurality of VLRs 40b and 40c. In particular, when the VLR capacity of any of a plurality of MSCs managing the same area is insufficient, the transfer destination MSC is determined by selecting the transfer destination MSC after grasping the free space of the VLR in advance. Can be prevented from falling into a loop that repeats transfer.

  A specific example of selecting the transfer destination MSC using the VLR capacity management database 60 will be described with reference to FIG. The transfer unit 31 of the MSC 30a that has received the location registration signal 1a from the mobile device 10 via the RNC 20 determines that the location registration signal is to be transferred because the capacity of the VLR 40a is insufficient.

  At this time, the transfer unit 31 transmits a capacity confirmation signal 1i to the VLR capacity management database 60 via the signal transmission / reception unit 34, and inquires about the free capacity of the VLRs 40b and 40c of the other MSCs 30b and 30c. The transfer unit 31 generates a capacity confirmation signal 1i specifying the VLR identifiers “VLR2” and “VLR3”.

  The VLR capacity management database 60 generates a capacity response signal 1j according to the capacity confirmation signal 1i and transmits it to the MSC 30a. The VLR capacity management database 60 acquires free capacity based on the VLR identifier specified in the capacity confirmation signal 1i. The VLR capacity management database 60 generates a capacity response signal 1j including the free capacity “10%” of the VLR 40b (VLR identifier = VLR2) and the free capacity “20%” of the VLR 40c (VLR identifier = VLR3).

  The transfer unit 31 receives the capacity response signal 1 j from the VLR capacity management database 60 via the signal transmission / reception unit 34. The transfer unit 31 selects the transfer destination MSC based on the free capacity of the VLRs 40b and 40c included in the capacity response signal 1j. For example, the transfer unit 31 selects the MSC 30c including the VLR 40c with the largest available capacity as the transfer destination MSC. The transfer unit 31 transfers the location registration transfer signal 1b to the MSC 30c.

  The MSC 30c performs the location registration process in the same manner as in FIG. Then, the control unit 33 of the MSC 30c transfers the location registration completion transfer signal 1d to the MSC 30a that is the transfer source MSC. The MSC 30a transmits a location registration completion signal 1e to the mobile device 10 via the RNC 20 in the same manner as in FIG. Note that the transfer unit 31 of the MSC 30a stops the transfer if any of the VLRs 40b and 40c has insufficient free space. Then, the transfer unit 31 transmits a location registration rejection signal 1h to the mobile device 10 via the RNC 20 in the same manner as in FIG.

  Further, when receiving the location registration signal, the transfer unit 31 of the MSC 30a may inquire the MSCs 30b and 30c about the free capacity of the respective VLRs 40b and 40c and select the transfer destination MSC based on the acquired free capacity.

  Regarding the determination of whether or not the location registration signal can be transferred and the selection of the transfer destination MSC, the mobile communication system 100 uses the number of times of transfer of the location registration signal, the transferred information, and the VLR capacity management database 60 shown in FIGS. Two or more may be combined.

(Mobile communication method)
Next, a procedure of a mobile communication method using the mobile communication system 100 will be described. FIG. 7 shows a processing procedure when the MSC 30 a receives the location registration signal 1 a from the mobile device 10. The MSC 30a receives the location registration signal 1a from the mobile device 10 via the RNC 20 (S101). The MSC 30a detects the free capacity of its own VLR 40a. The MSC 30a determines whether or not there is an available capacity for location registration (S102). When the VLR 40a has an available capacity for location registration, the MSC 30a acquires subscriber information of the mobile device 10 from the HLR 50, and performs location registration processing. Then, the MSC 30a transmits a location registration completion signal 1e including the MSC identifier (MSC1) of the MSC 30a itself that has performed location registration to the mobile device 10 (S103).

  On the other hand, in step (S102), if there is no free space available for location registration in the VLR 40a, the MSC 30a decides to transfer the location registration signal 1a and selects the transfer destination MSC (S104). If the transfer destination MSC can be selected, the MSC 30a transfers the location registration transfer signal 1b including the location registration signal 1a to the transfer destination MSC (S106).

  On the other hand, in step (S104), when the VLR of another MSC has no free space and the transfer destination MSC cannot be selected, the MSC 30a stops the transfer of the location registration signal and stops the location registration process. Then, the MSC 30a transmits a location registration rejection signal 1h to the mobile device 10 (S105).

  When the location registration signal 1a is transferred, the MSC 30a receives the location registration completion transfer signal 1d from the transfer destination MSC that has performed location registration (S107). The MSC 30a transmits a location registration completion signal 1e including an MSC identifier indicating the transfer destination MSC that has performed location registration to the mobile device 10 (S108).

  FIG. 8 shows a processing procedure when the MSC 30b receives the location registration transfer signal 1b from the transfer source MSC. The MSC 30b receives the location registration transfer signal 1b from the transfer source MSC (S201). The MSC 30b detects the free capacity of its own VLR 40b. The MSC 30b determines whether or not there is a free space that can be registered (S202). The MSC 30b acquires subscriber information of the mobile device 10 from the HLR 50 when the VLR 40b has a free capacity for location registration, and performs location registration processing. Then, the MSC 30b transmits a location registration completion transfer signal 1d including the MSC identifier (MSC2) of the MSC 30b itself that has performed location registration to the transfer source MSC (S203).

  On the other hand, in step (S202), if there is no free space available for location registration in the VLR 40b, the MSC 30b decides to transfer the location registration signal 1a and selects the transfer destination MSC (S204). If the transfer destination MSC can be selected, the MSC 30b transfers the location registration transfer signal 1b including the location registration signal 1a to the transfer destination MSC (S206).

  On the other hand, in step (S204), if the VLR of another MSC has no free capacity and the transfer destination MSC cannot be selected, the MSC 30b stops the transfer of the location registration signal and stops the location registration process. Then, the MSC 30b transmits a location registration rejection transfer signal 1g to the transfer source MSC (S205).

(effect)
According to the mobile communication system 100, the MSCs 30a to 30c, and the mobile communication method, even when the free space of the VLR of a certain MSC is small at the time of location registration, the location registration signal 1a is transferred to another MSC, The location of the mobile device 10 can be registered.

  In addition, location registration is performed in one MSC (transfer destination MSC), and the transfer source MSC can notify the mobile device 10 of the transfer destination MSC for which location registration has been performed. Therefore, after the location registration, the mobile device 10 can perform location registration and transmit a service request signal or the like to the transfer destination MSC that holds the subscriber information of the mobile device 10 in the VLR. That is, a signal related to outgoing / incoming calls is relayed to the MSC whose location is registered. Therefore, the MSCs 30a to 30c can provide mobile communication services to more mobile devices 10, and can prevent connection delay and signal amount increase at the time of outgoing / incoming calls.

  Thus, the mobile communication system 100 performs distributed processing by the Iu-Flex method, and efficiently accommodates the mobile device 10 in the VLR without impairing the service to the mobile device 10 or the processing capability of the network. A service can be provided to many mobile devices 10.

[Second Embodiment]
(Mobile communication system)
As shown in FIG. 9, the mobile communication system 200 includes a mobile device 10, an RNC 220, a plurality of MSCs 30a, 30b, and 30c, a plurality of VLRs 40a, 40b, and 40c, and an HLR 50. In the mobile communication system 200, the RNC 220 functions as a communication control device that transfers the location registration signal, and the RNC 220 transfers the location registration signal to the MSCs 30a to 30c based on the free space of the VLR. That is, the RNC 220 distributes the processing of the location registration signal from the mobile device 10 to the MSCs 30a to 30c. Except for this point, the mobile communication system 200 is substantially the same as the mobile communication system 100 shown in FIG.

  Next, the configuration of the RNC 220 will be described with reference to FIG. The RNC 220 includes a transfer unit 221, a VLR capacity management unit 222, a control unit 223, and a signal transmission / reception unit 224. The signal transmission / reception unit 224 transmits / receives signals to / from the mobile device 10, the base station, the MSCs 30a to 30c, and the like.

  The VLR capacity management unit 222 manages the capacity of the VLRs 40a to 40c. For example, the VLR capacity management unit 222 can hold the capacity of each VLR 40a to 40c. The transfer unit 221 is a transfer unit that transfers a location registration signal from the mobile device 10 to the transfer destination MSC according to the free capacity of the VLRs 40a to 40c. The transfer unit 221 determines whether or not the position registration signal can be transferred, and selects a transfer destination MSC. The control unit 223 performs various processes. In particular, the control unit 223 performs processing related to location registration. In addition, the control unit 223 functions as a notification unit that notifies the mobile device 10 of the transfer destination MSC for which location registration has been performed.

  Next, specific processing at the time of location registration and outgoing / incoming calls will be described. First, the process at the time of location registration will be described with reference to FIG.

  For example, the mobile device 10 performs position registration at the time of activation, change of a service area, or periodically. The mobile device 10 transmits a location registration signal 1a to the RNC 220 via the base station. The signal transmission / reception unit 224 receives the location registration signal 1a. The transfer unit 221 selects one MSC 30a from the MSCs 30a to 30c that manage the area where the mobile device 10 is located. For example, the transfer unit 221 refers to the VLR capacity management unit 222 and selects an MSC having a VLR with a large VLR capacity. The transfer unit 221 of the RNC 220 transfers the location registration signal 1a to the selected MSC 30a. In this way, the mobile device 10 can transmit the location registration signal 1a to any MSC via the RNC 220.

  The signal transmission / reception unit 34 of the MSC 30a receives the location registration signal 1a. The VLR management unit 32 detects the free capacity of the VLR 40a. The control unit 33 determines whether to process the location registration signal 1a in the MSC 30a based on the free space of the VLR 40a. For example, the transfer unit 31 can determine the free space threshold for determining whether or not the location registration process is possible in advance, and can compare the detected free space with the threshold.

  If the controller 33 determines that the VLR 40a has insufficient free space and cannot process the location registration signal 1a, it generates a location registration rejection signal 201h. The control unit 33 generates a location registration rejection signal 201h in which a reason display parameter indicating that location registration has been rejected due to insufficient free space in the VLR 40a is set. The control unit 33 transmits the generated location registration rejection signal 201h to the RNC 220 via the signal transmission / reception unit 34.

  The transfer unit 221 of the RNC 220 that has received the location registration rejection signal 201h from the MSC 30a determines from the reason display parameter set in the location registration rejection signal 201h that the location registration is rejected due to insufficient free space in the VLR 40a. Then, the transfer unit 221 selects a transfer destination MSC from the other MSCs 30b and 30c. Then, the transfer unit 221 transfers the position registration signal 1a again to the MSC 30b that is the newly selected transfer destination MSC.

  The MSC 30b that has received the location registration signal 1a detects the free space of the VLR 40b in the same manner as the MSC 30a. When the free space is insufficient, the MSC 30b also transmits a location registration rejection signal 201h to the RNC 220 in the same manner as the MSC 30a.

  The transfer unit 221 of the RNC 220 that has received the location registration rejection signal 201h from the MSC 30b determines from the reason display parameter set in the location registration rejection signal 201h that the location registration is rejected due to insufficient free space in the VLR 40b. Then, the transfer unit 221 selects another MSC 30c as the transfer destination MSC. Then, the transfer unit 221 transfers the position registration signal 1a again to the MSC 30b that is the newly selected transfer destination MSC.

  The control unit 33 of the MSC 30c that has received the location registration signal 1a determines whether or not to process the location registration signal 1a in the MSC 30c based on the free capacity of the VLR 40c. When the free space of the VLR 40c is sufficient for location registration, the control unit 33 performs location registration processing in the same manner as in FIG. After completion of the location registration process, the control unit 33 generates a location registration completion signal 1e in which the MSC identifier “MSC3” of the MSC 30c that has performed the location registration process is set. The control unit 33 transmits the generated location registration completion signal 1e to the RNC 220 via the signal transmission / reception unit 34.

  The RNC 220 transmits the location registration completion signal 1e in which the MSC identifier “MSC3” of the transfer destination MSC that has performed the location registration is set to the mobile device 10 via the signal transmission / reception unit 224, and the transfer destination MSC that has performed the location registration is transmitted. Notify the mobile device 10. The mobile device 10 that has received the location registration completion signal 1e stores the MSC identifier “MSC3” included in the location registration completion signal 1e. The MSC 30c is used for outgoing / incoming calls after location registration.

  Next, processing at the time of outgoing / incoming call will be described with reference to FIG. The mobile device 10 transmits a service request signal 1 f to the RNC 220 when making and receiving a call. At this time, the mobile device 10 sets the MSC identifier “MSC3” acquired during the location registration process in the service request signal 1f. The RNC 220 that has received the service request signal 1f determines the signal transmission destination to be the MSC 30c based on the MSC identifier “MSC3”, and transmits the service request signal 1f to the MSC 30c. In this way, the mobile device 10 can transfer the service request signal to the MSC 30c holding the subscriber information via the RNC 20. The MSC 30c that has received the service request signal 1f performs processing using the subscriber information held by its own VLR 40c.

  Thus, at the time of outgoing / incoming call, access to the MSCs 30a and 30b transferred by the location registration signal 1a at the time of location registration does not occur. That is, the process is the same as that performed when direct location registration is performed in the MSC 30c. The MSC 30c does not need to acquire subscriber information from the other VLRs 40a and 40b and the HLR 50. As a result, an increase in connection delay and signal amount can be prevented, and the processing load can be reduced.

  Next, whether or not the location registration signal can be transferred and selection of the transfer destination MSC will be described in more detail with reference to FIGS. The transfer unit 221 can determine whether or not the position registration signal can be transferred based on the transfer history of the position registration signal. The transfer history includes, for example, the number of times the position registration signal is transferred, the MSC to which the position registration signal has been transferred, and the like.

  When the number of transfers is used, the transfer unit 221 includes a counter 221a that counts the number of transfers as shown in FIG. The counter 221a holds mobile device identifiers “MS1” and “MS2” for identifying mobile devices and the number of transfers in association with each other. Each time the transfer unit 221 transfers the location registration signal to the MSC, the transfer unit 221 increases the transfer count associated with the mobile device that is the source of the location registration signal. That is, the counter value of the transfer count of the corresponding mobile device in the counter 221a is incremented by 1 for each transfer.

  The transfer unit 221 determines whether to perform transfer based on the number of transfers. For example, the transfer unit 221 can determine the threshold value of the transfer count for determining whether or not transfer is possible, and compare the transfer count held by the counter 221a with the threshold value. As the threshold value for the number of transfers, for example, the number of MSCs managing the same area can be set.

  When the transfer count reaches the threshold, the transfer unit 221 determines that transfer is not performed, and stops the transfer. According to this, when the capacity of the VLR of any of the plurality of MSCs managing the same area is insufficient, it is possible to prevent a loop in which the transfer destination MSC is obtained and the transfer is repeated many times.

  A specific example in which transfer is limited by the number of transfers will be described using FIG. The threshold for the number of transfers is set to the number “3” of the MSCs 30a to 30c managing the same area. The MS identifier of the mobile device 10 is “MS1”.

  The transfer unit 221 of the RNC 220 that has received the location registration signal 1a from the mobile device 10 selects the MSC 30a as the transfer destination MSC and transfers the location registration signal 1a. At this time, the transfer unit 221 adds 1 to the number of transfers associated with MS1 of the counter 221a to set the number of transfers to “1”.

  When the free space of the VLR 40a of the MSC 30a is insufficient, the RNC 220 receives the location registration rejection signal 201h. The transfer unit 221 compares the number of transfers “1” of the MS 1 of the counter 221 a with the threshold value “3”. The transfer unit 221 determines to transfer again because the number of transfers is less than the threshold. The transfer unit 221 selects the MSC 30b other than the MSC 30a that is the transferred MSC as the transfer destination MSC, and transfers the location registration signal 1a. At this time, the transfer unit 221 adds 1 to the number of transfers associated with MS1 of the counter 221 to set the number of transfers to “2”.

  When the free capacity of the VLR 40b of the MSC 30b is also insufficient, the RNC 220 receives the location registration rejection signal 201h. The transfer unit 221 compares the number of transfers “2” of the MS1 of the counter 221a with the threshold “3”. The transfer unit 221 determines to transfer again because the number of transfers is less than the threshold. The transfer unit 221 selects MSCs 30c other than the transferred MSCs 30a and 30b as transfer destination MSCs, and transfers the location registration signal 1a. At this time, the transfer unit 221 adds 1 to the number of transfers associated with MS1 of the counter 221a to set the number of transfers to “3”.

  When the free space of the VLR 40c of the MSC 30c is also insufficient, the RNC 220 receives the location registration rejection signal 201h. The transfer unit 221 compares the number of transfers “3” of the MS 1 of the counter 221 a with the threshold value “3”. The transfer unit 221 stops the transfer because the transfer count has reached the threshold value. In this case, the transfer unit 221 instructs the control unit 223 to reject the location registration process. The control unit 223 generates a location registration rejection signal 1h for notifying the mobile device 10 of location registration rejection. The control unit 223 transmits the generated location registration rejection signal 1h to the mobile device 10 via the signal transmission / reception unit 224.

  When the transferred information is used, the transfer unit 221 includes a transferred table 221b that holds the transferred information as shown in FIG. The transferred table 221b holds the mobile device identifiers “MS1” and “MS2” and the transferred MSC in association with each other. Each time the transfer unit 221 transfers the location registration signal to the MSC, the transfer unit 221 records the MSC identifier of the transferred MSC in association with the mobile device that transmitted the location registration signal.

  When selecting the transfer destination MSC, the transfer unit 221 selects the transfer destination MSC by referring to the transferred table 221b and excluding the transferred MSC. As described above, the transfer unit 221 holds the transferred information and determines the transfer destination MSC based on the transferred information, thereby avoiding repeatedly selecting the same MSC. In particular, when the VLR capacity of any of a plurality of MSCs managing the same area is insufficient, it is possible to prevent a loop in which a transfer destination MSC is obtained and transfer is repeated many times.

  A specific example of selecting the transfer destination MSC based on the transferred information will be described with reference to FIG. The transfer unit 221 of the RNC 220 that has received the location registration signal 1a from the mobile device 10 selects the MSC 30a as the transfer destination MSC and transfers the location registration signal 1a. At this time, the transfer unit 221 records “MSC1” indicating the MSC 30a in the transferred MSC associated with the MS1 of the transferred table 221b.

  When the free space of the VLR 40a of the MSC 30a is insufficient, the RNC 220 receives the location registration rejection signal 201h. The transfer unit 221 refers to the transferred table 221b and selects the MSC 30b other than the MSC 30a indicated by the transferred MSC “MSC1” as the transfer destination MSC. The transfer unit 221 adds “MSC2” indicating the MSC 30b to the transferred MSC associated with MS1 in the transferred table 221b.

  When the free capacity of the VLR 40b of the MSC 30b is also insufficient, the RNC 220 receives the location registration rejection signal 201h. The transfer unit 221 refers to the transferred table 221b and selects the MSC 30c other than the MSCs 30a and 30b indicated by the transferred MSCs “MSC1” and “MSC2” as the transfer destination MSC. The transfer unit 221 adds “MSC3” indicating the MSC 30c to the transferred MSC associated with the MS1 of the transferred table 221b.

  The MSC 30c that has received the location registration signal 1a performs location registration processing in the same manner as in FIG. 9 when the free space of the VLR 40c is sufficient, and transmits a location registration completion signal 1e to the RNC 220.

  When the transfer history is used as shown in FIGS. 12 and 13, the RNC 220 indicates that the transfer history indicates that there is no free space in any of the VLRs 40 a to 40 c (for example, when the number of transfers is large, it is not the transferred MSC. The location registration signal can be transferred according to the situation of the plurality of VLRs 40a to 40c, such as when the transfer of the location registration signal is stopped when the MSC does not exist.

  Furthermore, as shown in FIG. 14, the mobile communication system 200 may be provided with a VLR capacity management database 60 and used for selection of the transfer destination MSC. The VLR capacity management database 60 may be installed anywhere in the mobile communication system 200, may be provided in the RNC 220, the MSCs 30a to 30c, the HLR 50, or provided outside the RNC 220, the MSCs 30a to 30c, and the HLR 50. Also good.

  When the transfer unit 221 selects a transfer destination MSC, the transfer unit 221 acquires a free capacity from the VLR capacity management database 60, selects a transfer destination MSC based on the acquired free capacity, and transfers a location registration signal. Specifically, the transfer unit 221 inquires the VLR capacity management database 60 about the free capacity of another MSC, and selects an MSC having a free capacity that can be registered as a transfer destination MSC. According to this, the RNC 220 can easily acquire the free capacity of the plurality of VLRs 40a to 40c, and can appropriately select the transfer destination MSC based on the free capacity of the plurality of VLRs 40a to 40c. In particular, when the VLR capacity of any of a plurality of MSCs managing the same area is insufficient, the transfer destination MSC is determined by selecting the transfer destination MSC after grasping the free space of the VLR in advance. Can be prevented from falling into a loop that repeats transfer.

  A specific example of selecting the transfer destination MSC using the VLR capacity management database 60 will be described with reference to FIG. When the RNC 220 receives the location registration signal 1a, the transfer unit 221 transmits a capacity confirmation signal 1i to the VLR capacity management database 60 via the signal transmission / reception unit 224, and inquires about the free capacity of the VLRs 40a to 40c of the MSCs 30a to 30c.

  The VLR capacity management database 60 generates a capacity response signal 1j in response to the capacity confirmation signal 1i and transmits it to the RNC 220. The VLR capacity management database 60 generates a capacity response signal 1j including the free capacity “0%” of the VLR 40a, the free capacity “10%” of the VLR 40b, and the free capacity “20%” of the VLR 40c.

  The transfer unit 221 receives the capacity response signal 1j from the VLR capacity management database 60 via the signal transmission / reception unit 224. The transfer unit 221 selects the transfer destination MSC based on the free capacity of the VLRs 40a to 40c included in the capacity response signal 1j. For example, the transfer unit 221 selects the MSC 30c including the VLR 40c having the largest free space as the transfer destination MSC. The transfer unit 221 transfers the location registration signal 1a to the MSC 30c. The MSC 30c performs the location registration process in the same manner as in FIG.

  Note that the transfer unit 221 transfers the location registration signal 1a once to any MSC even if any of the VLRs 40a to 40c has insufficient free space. Then, the transfer unit 221 receives the location registration rejection signal 201h from the MSC. Since the transfer unit 221 knows that any of the VLRs 40a to 40c has insufficient free space, the transfer unit 221 instructs the control unit 223 to reject the location registration process. The control unit 223 transmits a location registration rejection signal 1h to the mobile device 10 based on the received location registration rejection signal 201h. Thus, even if the RNC 220 knows that any of the VLRs 40a to 40c has insufficient free space, at least once to transmit the location registration rejection signal 1h to the mobile device 10. Transfers the location registration signal 1a to the MSC and receives the location registration rejection signal 201h from the MSC.

  Further, the VLR capacity management unit 222 may periodically acquire the free capacity of the VLRs 40a to 40c from the VLR capacity management database 60 and hold it. In this case, the transfer unit 221 can acquire the free capacity from the VLR capacity management unit 222. Alternatively, when the RNC 220 receives the location registration signal, the transfer unit 221 may inquire the MSCs 30a to 30c about the free capacity of the respective VLRs 40a to 40c and select the transfer destination MSC based on the acquired free capacity.

  Regarding the determination of whether or not the location registration signal can be transferred and the selection of the transfer destination MSC, the mobile communication system 200 uses the method of using the location registration signal transfer count, the transferred information, and the VLR capacity management database 60 shown in FIGS. Two or more may be combined.

(Mobile communication method)
Next, a procedure of a mobile communication method using the mobile communication system 200 will be described. As shown in FIG. 15, the RNC 220 receives the location registration signal 1a from the mobile device 10 (S301). The RNC 220 selects the transfer destination MSC (S302), and transfers the location registration signal 1a to the selected transfer destination MSC (S303).

  The RNC 220 receives either the location registration completion signal 1e or the location registration rejection signal 201h from the transfer destination MSC (S304). When the RNC 220 receives the location registration completion signal 1e, the RNC 220 transmits a location registration completion signal 1e including an MSC identifier indicating the transfer destination MSC that has performed location registration to the mobile device 10 (S305).

  On the other hand, in step (S304), when the RNC 220 receives the location registration rejection signal 201h, the RNC 220 selects the transfer destination MSC again (S306). If the transfer destination MSC can be selected, the RNC 220 transmits the location registration signal 1a to the selected transfer destination MSC again (S308).

  On the other hand, in step (S306), if there is no free space in any VLR and the transfer destination MSC cannot be selected, the RNC 220 stops the transfer of the location registration signal and stops the location registration process. Then, the RNC 220 transmits a location registration rejection signal 1h to the mobile device 10 (S307).

(effect)
According to such mobile communication system 200, RNC 220, and mobile communication method, even when the free space of VLR of a certain MSC is small at the time of location registration, the location registration signal 1a is transferred to another MSC, and the mobile device Ten location registrations can be performed.

  In addition, the location registration process is transferred to another MSC, the location registration is performed in one MSC (transfer destination MSC), and the RNC 220 can notify the mobile device 10 of the transfer destination MSC in which the location registration has been performed. Therefore, after the location registration, the mobile device 10 can perform location registration and transmit a service request signal or the like to the transfer destination MSC that holds the subscriber information of the mobile device 10 in the VLR. That is, a signal related to outgoing / incoming calls is relayed to the MSC whose location is registered. Therefore, the RNC 220 can provide a mobile communication service to more mobile devices 10 and can prevent an increase in connection delay and signal amount at the time of outgoing / incoming calls.

  As described above, the mobile communication system 200 performs distributed processing by the Iu-Flex method, and efficiently accommodates the mobile device 10 in the VLR without impairing the service to the mobile device 10 or the processing capability of the network. A service can be provided to many mobile devices 10.

[Example of change]
The present invention is not limited to the above embodiment, and various modifications can be made. In the above embodiment, MSCs and VLRs according to the circuit switching system are used as the exchanges and area subscriber information holding means. However, SGSNs (Serving GRPS Support Nodes) according to the packet switching system are used as the exchanges and area subscriber information holding means. It may be used.

It is a figure which shows the process at the time of the position registration of the mobile communication system which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structure of MSC and VLR which concern on the 1st Embodiment of this invention. It is a figure which shows the process at the time of the transmission / reception of the mobile communication system which concerns on the 1st Embodiment of this invention. It is a figure which shows the case where the frequency | count of transfer which concerns on the 1st Embodiment of this invention is used. It is a figure which shows the case where the transferred information which concerns on the 1st Embodiment of this invention is used. It is a figure which shows the case where the VLR capacity management database which concerns on the 1st Embodiment of this invention is used. It is a flowchart which shows the process sequence at the time of receiving the position registration signal from the mobile apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the process sequence when the position registration transfer signal is received from transfer origin MSC which concerns on the 1st Embodiment of this invention. It is a figure which shows the process at the time of the position registration of the mobile communication system which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structure of RNC which concerns on the 2nd Embodiment of this invention. It is a figure which shows the process at the time of the transmission / reception of the mobile communication system which concerns on the 2nd Embodiment of this invention. It is a figure which shows the case where the frequency | count of transfer which concerns on the 2nd Embodiment of this invention is used. It is a figure which shows the case where the transferred information which concerns on the 2nd Embodiment of this invention is used. It is a figure which shows the case where the VLR capacity management database which concerns on the 2nd Embodiment of this invention is used. It is a flowchart which shows the procedure of the mobile communication method which concerns on the 2nd Embodiment of this invention. It is a figure which shows the process at the time of the conventional location registration. It is a figure which shows the process at the time of the conventional outgoing / incoming call. It is a figure which shows the subject of the method of deleting subscriber information. It is a figure which shows the subject of the method of storing subscriber information in another VLR.

Explanation of symbols

10,310 mobile station 20,220,320 RNC
30a, 30b, 30c, 330a, 330b, 330c MSC
31, 221 Transfer unit 32 VLR management unit 33, 223 Control unit 34, 224 Signal transmission / reception unit 40a, 40b, 40c, 340a, 340b, 340c VLR
41 Subscriber Information Management Unit 42 Subscriber Information Memory 50,350 HLR
221a Counter 221b Transferred table 222 VLR capacity management unit

Claims (6)

In a communication system comprising a plurality of exchanges and a plurality of area subscriber information holding means respectively corresponding to the plurality of exchanges, a position registration signal transmitted by a mobile station to one exchange among the plurality of exchanges is processed. A communication control device,
Of the plurality of area subscriber information holding means, the location registration signal is sent to another exchange among the plurality of exchanges according to the free space of one area subscriber information holding means corresponding to the one exchange. A transfer means for transferring;
A notification means for notifying the mobile station of the other exchange when the location of the mobile station is registered by the other exchange;
A communication control apparatus, wherein a service request signal for requesting provision of a service is transmitted from the mobile station to the other exchange.   The communication control apparatus according to claim 1, wherein the transfer unit determines whether to transfer the location registration signal based on a transfer history of the location registration signal.   The communication control device according to claim 2, wherein the transfer unit transfers the transfer history together with the location registration signal to the other exchange.   The transfer means acquires the free capacity of the one area subscriber information holding means from a capacity management device that manages the free capacity of the plurality of area subscriber information holding means. Item 4. The communication control device according to any one of Items 3 to 4.   The communication control apparatus according to any one of claims 1 to 4, wherein the communication control apparatus is a radio control apparatus connected to the plurality of exchanges or the exchange. In a communication system comprising a plurality of exchanges and a plurality of area subscriber information holding means respectively corresponding to the plurality of exchanges, a position registration signal transmitted by a mobile station to one exchange among the plurality of exchanges is processed. A mobile communication method
Of the plurality of area subscriber information holding means, the location registration signal is sent to another exchange among the plurality of exchanges according to the free space of one area subscriber information holding means corresponding to the one exchange. A transfer step;
Notifying the other exchange to the mobile station when the location of the mobile station is registered by the other exchange, and
A mobile communication method, wherein a service request signal for requesting provision of a service is transmitted from the mobile station to the other exchange.

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