JP4896241B2 - Communication control device and location registration method - Google Patents

Description

  The present invention relates to a communication control device that controls location registration from a mobile terminal and a location registration method that performs location registration from a mobile terminal.

  Patent Document 1 discloses a technique related to a mobile communication system in which a base station for a specific user is introduced. When it is detected that a mobile station permitted to access the base station for specific users has entered or appeared in the location registration area associated with the base station for specific users, at least after the detection, the specific The mobile station individually notifies connection information including frequency information currently used by the user base station and ID information of the base station for specific users. The mobile station performs a cell search based on the notified connection information. Specifically, the mobile station receives the frequency information of the neighboring cell broadcast from the general public base station in which the mobile station is located, and based on the frequency information and the neighboring cell frequency information included in the notified connection information. Cell search.

JP 2008-278264 A

  When the communication area and frequency band of the base station for specific users overlap with the communication area and frequency band of the general public base station, the following may occur. For mobile stations that have already been registered for general public base stations, bands are allocated to other frequency bands that overlap the frequency band of the base station for specific users. When the strength is strong, the mobile station makes a location registration request to the base station for the specific user, not to the general public base station. However, if this mobile station is not allowed to register the location for the base station for specific users (this mobile station does not belong to a specific user), the location registration for the base station for specific users of this mobile station is rejected. The original frequency band is restored (frequency eviction). After that, band allocation may be performed again for this mobile station. In such a case, the above-described band allocation and frequency eviction are repeated. In this way, if the communication area and frequency band of the base station for specific users and the communication area and frequency band of the general public base station overlap each other, a flutter occurs at the time of location registration as described above, and wasteful communication processing occurs. May be performed. In such a case, the battery of the mobile station is consumed quickly, and the load on the communication processing on the communication network side such as the base station is further increased.

  Therefore, the present invention has been made in view of the above matters, and even for a mobile terminal that does not belong to a specific user, the communication area and frequency band of the base station for the specific user and the communication area of the general public base station and An object of the present invention is to perform location registration without excessively increasing the load on the communication processing of the battery of the mobile terminal and the base station when the frequency bands overlap each other.

  A communication control apparatus according to the present invention is a communication control apparatus that controls location registration of a mobile terminal performed for a first or second radio base station in which both a communication area and a frequency band overlap. A recording apparatus for recording an identification number of a mobile terminal capable of performing location registration with respect to one radio base station, and performing location registration of the mobile terminal with respect to the first or second radio base station and the recording Location registration means for rejecting location registration for the first radio base station from a mobile terminal whose identification number is not recorded in the device, and the number of rejections where location registration is rejected by the location registration means is counted for each mobile terminal And counting means for storing the count value in the recording device, wherein the first radio base station has a smaller communication area than the second radio base station, and When the count value reaches a threshold value, the means performs location registration of the mobile terminal corresponding to the count value with respect to the first radio base station, and the count means performs location registration with respect to the first radio base station. The count value is cleared when it is performed by the position registration means, and the count value is not cleared when the position registration with respect to the second radio base station is performed by the position registration means.

  As described above, in the case where the mobile terminal is a terminal that is not registered for permission to visit the first radio base station, if the count value indicating the number of refusal of location registration has reached the threshold, Location registration of mobile terminals is allowed. In addition, even when the location registration of the mobile terminal with respect to the second radio base station is performed, the count value corresponding to the mobile terminal is not cleared and held, so Even when the location registration rejection for one radio base station is repeated, if the count value reaches the threshold value, the location registration for the first radio base station is performed. Can be reduced. Therefore, location registration can be performed without imposing an excessive load on the communication processing of the battery of the mobile terminal, the first radio base station, the second radio base station, and the communication control apparatus.

  The communication control apparatus according to the present invention uses the mobile terminal currently registered among the plurality of frequency bands of the second radio base station to the mobile terminal for which location registration is performed for the second radio base station. If a change to another frequency band that is different from the existing frequency band is instructed and position registration in the change destination frequency band is rejected by the position registration means, the change to the change destination frequency band is different for the mobile terminal. Frequency band changing means for instructing location registration in another frequency band may be further provided. Therefore, even when the mobile terminal is once allowed to register the location with respect to the second radio base station, a change to another frequency band is made and the location registration with respect to the first radio base station is requested. Since the count value up to the previous time of the mobile terminal is held, the process of registering the position in another frequency band (for example, the original frequency band before the change) different from the change destination frequency band is repeated several times. Even if the increment of the count value continues, if the count value reaches the threshold value, the position registration is performed in another frequency band (for example, the original frequency band before the change) different from the frequency band after the change. No processing is performed, and finally, location registration for the first radio base station is permitted, and the flutter at the time of location registration is eliminated. Therefore, location registration can be performed without imposing an excessive load on the communication processing of the battery of the mobile terminal, the first radio base station, the second radio base station, and the communication control apparatus.

  The location registration method according to the present invention is a location registration method in which a communication control device performs location registration of a mobile terminal with respect to a first or second radio base station having both overlapping communication areas and frequency bands. The communication control device determines whether the mobile terminal is registered in advance as a terminal capable of performing location registration with respect to the first radio base station upon receiving a location registration request from the first radio base station. And when the communication control apparatus determines that the mobile terminal is not a terminal capable of performing location registration with the first radio base station in the first step. The communication control apparatus rejects the location registration of the mobile terminal with respect to the base station, and the communication control is performed with a count value indicating the number of times the mobile terminal location registration with respect to the first radio base station is rejected. A second step of updating the device, and when the communication control device registers the position of the mobile terminal with respect to the second radio base station after the second step, the communication control device holds the count value. When the request for location registration to the first radio base station is made again from the mobile terminal to the communication control device after the third step, whether the count value has reached the threshold value When the communication control device determines that the count value has reached the threshold value in the fourth step, and the communication control device clears the count value. And a fifth step of permitting location registration of the mobile terminal with respect to the first radio base station.

  As described above, in the case where the mobile terminal is a terminal that is not registered for permission to visit the first radio base station, if the count value indicating the number of refusal of location registration has reached the threshold, Location registration of mobile terminals is allowed. In addition, even when the location registration of the mobile terminal with respect to the second radio base station is performed, the count value corresponding to the mobile terminal is not cleared and held, so Even when the location registration rejection for one radio base station is repeated, if the count value reaches the threshold value, the location registration for the first radio base station is performed. Can be reduced. Therefore, location registration can be performed without imposing an excessive load on the communication processing of the battery of the mobile terminal, the first radio base station, the second radio base station, and the communication control apparatus.

  According to the present invention, even if a mobile terminal does not belong to a specific user, the communication area and frequency band of the base station for the specific user overlap with the communication area and frequency band of the base station for the general public, respectively. In addition, location registration can be performed without excessively increasing the load on the mobile terminal battery or base station communication processing.

FIG. 1 is a diagram illustrating a configuration of a communication control system according to the embodiment. FIG. 2 is a diagram illustrating a physical configuration of the core network device according to the embodiment. FIG. 3 is a diagram illustrating a functional configuration of the core network device according to the embodiment. FIG. 4 is a flowchart for explaining processing of the core network device according to the embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the description of the drawings, if possible, the same elements are denoted by the same reference numerals, and redundant description is omitted. FIG. 1 is a diagram illustrating a configuration of the communication control system 1. The communication control system 1 includes a femto BTS 3 (BTS: Base Transceiver Station), a macro BTS 5 (BTS: Base Transceiver Station), an RNC 7 (RNC: Radio Network Controller), a core network device 9, and a mobile terminal 11.

  The femto BTS 3 is a radio base station that is in charge of a communication area (femtoCell 3a) having a radius of several tens of meters. The femto BTS 3 is a radio base station for a specific user. The mobile terminals that can perform location registration with respect to femtoBTS 3 are limited to those that have been registered in the core network apparatus 9 for permission to visit with femtoBTS 3 in advance. Note that the mobile terminal 11 can be a terminal that has been previously registered in the area permission registration for the femtoBTS 3, or can be a terminal that has not been previously registered for the area permission registration for the femto BTS 3. The location permission registration for the femtoBTS 3 is performed by the core network device 9. The location permission registration for the femto BTS 3 is performed by the core network device 9 using the identification information such as the telephone number of the mobile terminal 11 and the identification information of the femto BTS 3. The frequency band used by femto BTS 3 is, for example, a 2000 MHz band.

  The macro BTS 5 is a radio base station that is in charge of a wider communication area (macroCell 5a) than the femto BTS 3. It is assumed that the macroCell 5a includes a femtoCell 3a. The macro BTS 5 is a radio base station for the general public. The location permission registration is not required for the location registration for the macro BTS 5. The macro BTS 5 uses, for example, three frequency bands. The frequency bands used by the macro BTS 5 are, for example, a 2000 MHz band, a 1700 MHz band, and an 800 MHz band.

  The RNC 7 is communicatively connected to the femto BTS 3, the macro BTS 5, and the core network device 9. The RNC 7 is a radio resource control device, and mediates communication between the core network device 9 and the femto BTS 3 and the macro BTS 5. The communication control system 1 shown in FIG. 1 has a configuration in which the femto BTS 3 and the macro BTS 5 are connected to the same RNC 7. However, the present invention is not limited to this configuration, and each of the femto BTS 3 and the macro BTS 5 has a configuration connected to different RNCs 7. Can do.

  The core network device 9 is a communication control device that performs communication control of the mobile terminal 11, and in particular controls location registration of the mobile terminal 11. The location registration controlled by the core network device 9 includes location registration for the femtoBTS 3 and location registration for the macro BTS 5.

  The core network device 9 has the number of mobile terminals currently in use with respect to the mobile terminal 11 in which the location registration for the macro BTS 5 is performed, in comparison with the frequency band currently used by the mobile terminal 11 among the plurality of frequency bands of the macro BTS 5. Instruct to change to other frequency bands (band distribution). The core network device 9 transmits another frequency band different from the change destination frequency band to the mobile terminal 11 whose location registration is rejected in the change destination frequency band after the change of the frequency band (after the band allocation). For example, it is instructed to register the position in the original frequency band before change (frequency eviction).

  The core network device 9 performs the registration for the femtoBTS 3 based on the information indicating the location permission registration for the femto BTS 3 (information in which the identification information of the femto BTS 3 and the identification information of the mobile terminal 11 whose location registration is previously permitted for the femto BTS 3 are associated). It is determined whether or not the location registration of the mobile terminal 11 is performed. Specifically, the core network device 9 stores the identification information of the mobile terminal 11 whose location registration with respect to the femtoBTS 3 is permitted (that is, where the location permission registration is performed) in the internal memory of the core network device 9 together with the identification information of the femtoBTS 3. It is determined whether the mobile terminal 11 is permitted to be located in the femto BTS 3, that is, whether or not to register the location of the mobile terminal 11 with respect to the femto BTS 3 by referring to the stored identification information of the mobile terminal 11 and femto BTS 3. To do.

  When the core network device 9 receives a location registration request for the femtoBTS 3 from the mobile terminal 11 that is registered for location permission, the core network device 9 permits the location registration. When the core network device 9 receives a location registration request for the femtoBTS 3 from the mobile terminal 11 that has not been registered for location permission, the core network device 9 rejects the location registration and counts the number of times the location registration of the mobile terminal 11 is rejected (rejection). (Total number of times) is incremented by one. When the count value reaches a preset threshold value, the core network device 9 registers the location of the mobile terminal 11 corresponding to this count value, that is, the mobile terminal 11 that refuses location registration for the femtoBTS 3 by the number of count values. The count value that has reached the threshold is cleared (set to zero). If the location registration for the macro BTS 5 is permitted, the core network device 9 continues to hold the count value without clearing the location registration even after the location registration for the femto BTS 3 is rejected. When the core network device 9 receives a location registration request for the femtoBTS 3 from the mobile terminal 11 that has been registered for permission to visit, the core network device 9 clears the count value corresponding to the mobile terminal 11.

  The mobile terminal 11 is a terminal such as a mobile phone that can communicate with the femto BTS 3 and the macro BTS 5. When the mobile terminal 11 performs location registration for the femto BTS 3, the mobile terminal 11 transmits the identification information of the mobile terminal 11 to the femto BTS 3, and the femto BTS 3 passes the received identification information of the mobile terminal 11 and the identification information of the femto BTS 3 via the RNC 7. To the core network device 9. The core network device 9 controls location registration of the mobile terminal 11 based on the identification information of the mobile terminal 11 and the identification information of the femtoBTS 3 received via the RNC 7 (location registration for determining whether or not to perform location registration). Or reject location registration). When the mobile terminal 11 performs location registration for the macro BTS 5, the mobile terminal 11 transmits the identification information of the mobile terminal 11 to the macro BTS 5, and the macro BTS 5 transmits the received identification information of the mobile terminal 11 and the identification information of the macro BTS 5 via the RNC 7. To the core network device 9. The core network device 9 registers the location of the mobile terminal 11 based on the identification information of the mobile terminal 11 and the identification information of the macro BTS 5 received via the RNC 7.

  FIG. 2 is a diagram illustrating a physical configuration of the core network device 9. The core network device 9 physically includes a CPU 91, a ROM 92, a RAM 93, a recording device 94, a communication device 95, and a bus 96. The CPU 91 is stored in a built-in memory of the core network device 9 such as the ROM 92. The core network device 9 is centrally controlled by loading a predetermined computer program (for example, a computer program for performing the processing shown in the flowchart of FIG. 4) into the RAM 93 and executing it.

  The recording device 94 is a memory capable of writing / reading, and stores data indicating identification numbers of the femto BTS 3 and the macro BTS 5. The recording device 94 stores information indicating in-zone permission registration, that is, data in which the identification number (for example, a telephone number) of the mobile terminal 11 that can perform location registration for the femtoBTS 3 is associated with the identification number of the femtoBTS 3. The recording device 94 stores, for each identification number of the mobile terminal 11, a count value indicating the number of times the location registration of the mobile terminal 11 with respect to the femto BTS 3 is rejected.

  The communication device 95 has an interface for communicating with the RNC 7 and can communicate with the femto BTS 3 and the macro BTS 5 via the RNC 7. The communication device 95 can communicate with the mobile terminal 11 via the femtoBTS3, the macroBTS5, and the RNC7. When the femto BTS 3 and the macro BTS 5 are connected to different RNCs 7, the communication device 95 has an interface for communicating with the RNC 7 connected to the femto BTS 3, and the femto BTS 3 via the RNC 7. The communication device 95 has an interface for communicating with the RNC 7 connected to the macro BTS 5, and can communicate with the macro BTS 5 via the RNC 7. The communication device 95 can communicate with the mobile terminal 11 via the femto BTS 3 and the RNC connected to the femto BTS 3, and the communication device 95 communicates with the mobile terminal 11 via the macro BTS 5 and the RNC 7 connected to the macro BTS 5. Can be done.

  FIG. 3 is a diagram illustrating a functional configuration of the core network device 9. Functionally, the core network device 9 includes a location registration unit 91a, a base station determination unit 91b, a count unit 91c, a registration determination unit 91d, and a rejection count determination unit 91e. The location registration unit 91a, the base station determination unit 91b, the count unit 91c, the registration determination unit 91d, and the rejection number determination unit 91e are computer programs stored in the internal memory (ROM 92, recording device 94, etc.) of the core network device 9 by the CPU 91. It is a function realized by executing. The CPU 91 sequentially executes the processing shown in the flowchart of FIG. 4 by executing this computer program (using the count unit 91c, the registration determination unit 91d, the base station determination unit 91b, and the rejection count determination unit 91e). Various data necessary for the execution of the computer program and various data generated by the execution of the computer program can all be stored in the ROM 92, the RAM 93, and the recording device 94 of the core network device 9.

  The location registration unit 91a performs location registration processing (permits location registration and performs location registration) in response to a request for location registration of the mobile terminal 11 to the femto BTS 3 and a request for location registration of the mobile terminal 11 to the macro BTS 5. , Reject location registration). When the location registration unit 91a receives a location registration request for the femtoBTS 3 from the mobile terminal 11 in which the location permission registration for the femto BTS 3 is performed, the location registration unit 91a permits the location registration. If there is a location registration request from a mobile terminal 11 that has not been registered for location permission for femtoBTS3, the location registration unit 91a moves to femtoBTS3 if the count value corresponding to this mobile terminal 11 is less than a certain threshold value Sr1. When the location registration of the terminal 11 is rejected and the count value corresponding to the mobile terminal 11 is not less than the threshold value Sr1 and less than the threshold value Sr2 (Sr1 <Sr2), the location registration of the mobile terminal 11 with respect to the femtoBTS3 is rejected and the femtoBTS3 The femto BTS 3 is instructed to lower the radio field strength to a preset strength. When the count value corresponding to the mobile terminal 11 reaches the threshold value Sr2, the location registration for the femto BTS 3 is permitted and the location registration is performed.

  Upon receiving the location registration request, the base station determination unit 91b determines whether this location registration is location registration with respect to femtoBTS3 or location registration with respect to macroBTS5.

  The count unit 91c counts the number of rejections (count value) in which the location registration of the mobile terminal 11 with respect to the femtoBTS 3 is rejected by the location registration unit 91a, and stores this count value in the recording device 94 for each identification information of the mobile terminal 11. . When there is a location registration request from the mobile terminal 11 that has not been registered to permit access to the femtoBTS 3 and the location registration is rejected by the location registration unit 91a, the count unit 91c counts corresponding to the mobile terminal 11. Is incremented by one. When the count value reaches the threshold value Sr1, the count unit 91c clears the count value (sets it to zero). When the location registration for the macro BTS 5 is permitted, the count unit 91c continues to hold the count value without clearing the location registration even after the location registration for the femto BTS 3 is rejected. When the count unit 91c receives a location registration request for the femtoBTS 3 from the mobile terminal 11 that is registered for permission to visit the femto BTS 3, the count unit 91c clears the count value corresponding to the mobile terminal 11.

  When there is a location registration request for femtoBTS 3, registration determination unit 91 d determines whether mobile terminal 11 that has made this request is a terminal that has been registered for permission to access femtoBTS 3.

  When there is a location registration request from the mobile terminal 11 that has not been registered for permission to visit the femto BTS 3, the rejection number determination unit 91 e determines whether the count value corresponding to the mobile terminal 11 reduces the radio field intensity of the femto BTS 3 to a predetermined value. It is determined whether or not threshold values (threshold value Sr1 and threshold value Sr2) for determining whether or not to perform location registration have been reached.

  The frequency band changing unit 91f allows the mobile terminal 11 that has been registered for the location of the macro BTS 5 to have the number of terminals currently in use more than the frequency band currently used by the mobile terminal 11 among the plurality of frequency bands of the macro BTS 5. Instruct to change to other frequency bands (band distribution). When the location registration is rejected in the change destination frequency band due to the change (band distribution) of the frequency band, the frequency band changing unit 91f gives the change destination frequency to the mobile terminal 11 in which the location registration is rejected. An instruction is given to perform location registration in another frequency band different from the band (for example, the original frequency band before the change) (frequency eviction).

  Next, the operation of the core network device 9 will be described with reference to FIG. When the location registration unit 91a receives a location registration request from the mobile terminal 11 (step S1), the base station determination unit 91b determines whether the location registration is location registration for the femtoBTS3 or location registration for the macroBTS5. Is determined (step S2).

  In step S2, if the base station determination unit 91b determines that the location registration is for femtoBTS 3 (step S2; femto BTS), the location registration unit 91a starts location registration for femto BTS 3 (step S3).

  After step S3, the registration determination unit 91d determines whether or not the mobile terminal 11 is a terminal that has been registered for the femtoBTS 3 (whether or not the mobile terminal 11 has been registered for the area permission). In step S4), when the registration determination unit 91d determines that the mobile terminal 11 is a terminal that is permitted to be located in the area (step S4; registered), the count unit 91c counts corresponding to the mobile terminal 11. The value is cleared (step S5), and thereafter, the location registration unit 91a registers the location of the mobile terminal 11 with respect to the femtoBTS 3 (step S6).

  In step S4, when the registration determination unit 91d determines that the mobile terminal 11 is not a terminal that has been registered to permit access to the femto BTS 3 (step S4; not registered), the rejection count determination unit 91e The magnitude relationship between the corresponding count value and the threshold values Sr1 and Sr2 is determined (step S7).

  In step S7, when the count value corresponding to the mobile terminal 11 is less than the threshold value Sr1 (step S7; 0 ≦ count value <threshold value Sr1), the counting unit 91c increments the count value corresponding to the mobile terminal 11 by one ( Thereafter, the location registration unit 91a rejects the location registration of the mobile terminal 11 with respect to the femto BTS 3 (step S9).

  In step S7, when the count value corresponding to the mobile terminal 11 is not less than the threshold value Sr1 and less than the threshold value Sr2 (step S7; threshold value Sr1 ≦ count value <threshold value Sr2), the counting unit 91c sets the count value corresponding to the mobile terminal 11 to one. After that, the location registration unit 91a rejects the location registration of the mobile terminal 11 with respect to the femtoBTS 3, and sets the radio field strength of the femto BTS 3 to a preset strength (the current of the mobile terminal 11 in the femtoCell 3a). A signal instructing the femto BTS 3 to be lowered to a position below the radio field intensity of the macro BTS 5 at the position is transmitted to the femto BTS 3 (step S11). Since the mobile terminal 11 performs position registration with respect to the base station having strong radio field strength among the femto BTS 3 and macro BTS 5, the radio field intensity of the femto BTS 3 is less than the radio field intensity of the macro BTS 5 at the current position of the mobile terminal 11 in the femtoCell 3a. By being reduced to a high strength, the mobile terminal 11 can easily perform location registration for the macro BTS 5.

  In step S7, when the count value corresponding to the mobile terminal 11 is greater than or equal to the threshold value Sr2 (step S7; threshold value Sr2 ≦ count value), the count unit 91c clears the count value corresponding to the mobile terminal 11 (step S12). Thereafter, the location registration unit 91a permits location registration of the mobile terminal 11 with respect to the femto BTS 3, and performs this location registration (step S13).

  In step S2, if the base station determination unit 91b determines that the location registration requested in step S1 is location registration for the macro BTS 5 (step S2; macro BTS), the location registration unit 91a starts location registration for the macro BTS 5. (Step S14), the count unit 91c continues to hold the count value corresponding to the mobile terminal 11 (Step S15). After step S14 and step S15, the location registration unit 91a registers the location of the mobile terminal 11 with respect to the macro BTS 5 (step S16).

  In particular, after step S9 or step S11, when the location registration of the mobile terminal 11 with respect to the macroBTS 5 is performed in step S16 by, for example, frequency eviction by the frequency band changing unit 91f, the count value corresponding to the mobile terminal 11 Is retained in step S15. Thereafter, in step S1, when a request for location registration for the femtoBTS 3 is made again from the mobile terminal 11, for example, by band allocation by the frequency band changing unit 91f, the steps S2, S3, and S4 are performed. Through the above processes, it is determined in step S7 whether or not the count value corresponding to the mobile terminal 11 has reached the threshold value Sr2, and if it is determined that the count value corresponding to the mobile terminal 11 has reached the threshold value ( Step S7: Threshold value Sr2 ≦ K Cement value), the count value corresponding to the mobile terminal 11 is cleared (step S12), the location registration of the mobile terminal 11 is permitted with respect to FemtoBTS3 (step S13).

  As described above, in the case where the mobile terminal 11 is a terminal that is not registered to permit access to the femto BTS 3, if the count value indicating the number of times of location registration rejection reaches the threshold value Sr2, the location registration of the mobile terminal 11 with respect to the femto BTS 3 is permitted. Is done. After the mobile terminal 11 is once granted location registration by the macro BTS 5, for example, even when the band is allocated and the location registration for the femto BTS 3 is requested, the count value until the previous time of the mobile terminal 11 is held. Even if the band allocation and the frequency extraction are repeated several times and the count value continues to be incremented, if the count value reaches the threshold value Sr2, then the band allocation and the frequency extraction are not performed, and finally the femtoBTS3 Location registration for is allowed. Therefore, location registration can be performed without excessively increasing the load on the battery of the mobile terminal 11 and the communication processing of the base station.

  Next, functions and effects of the core network device 9 according to the embodiment will be described. The core network device 9 is a communication control device that controls the location registration of the mobile terminal 11 performed for the femto BTS 3 and the macro BTS 5 in which both the communication area and the frequency band overlap. The core network device 9 includes a recording device 94, a location registration unit 91a, and a count unit 91c. The recording device 94 records the identification number of the mobile terminal capable of performing location registration with respect to the femto BTS 3 (information included in the location permission registration with respect to the femto BTS 3). The location registration unit 91a performs location registration of the mobile terminal 11 with respect to femtoBTS3 and macroBTS5, but the identification number is not recorded in the recording device 94 (that is, the location permission registration with respect to femtoBTS3 is not performed). Reject location registration for. The count unit 91c counts the number of times the location registration is rejected by the location registration unit 91a for each mobile terminal, and stores this count value in the recording device 94. The communication area (femtoCell3a) of femtoBTS3 is narrower than the communication area (macroCell5a) of macroBTS5. When the count value corresponding to the mobile terminal 11 reaches the threshold value Sr2, the location registration unit 91a performs location registration for the femto BTS 3 of the mobile terminal 11 corresponding to the count value. When the location registration of the mobile terminal 11 with respect to the femtoBTS 3 is performed by the location registration unit 91a, the count unit 91c clears the count value corresponding to the mobile terminal 11 stored in the recording device 94, and the mobile terminal 11 with respect to the macro BTS 5 When the location registration is performed by the location registration unit 91a, the count value corresponding to the mobile terminal 11 stored in the recording device 94 is not cleared.

  As described above, in the case where the mobile terminal 11 is a terminal that is not registered to permit access to the femto BTS 3, if the count value indicating the number of times of location registration rejection reaches the threshold value Sr2, the location registration of the mobile terminal 11 with respect to the femto BTS 3 is permitted. Is done. Further, even when the location registration of the mobile terminal 11 with respect to the macro BTS 5 is performed, the count value corresponding to the mobile terminal 11 is not cleared but is retained, so that location registration with respect to the macro BTS 5 and rejection of location registration with respect to the femto BTS 3 are repeated. Even if the count value has reached the threshold value Sr2, position registration with respect to femtoBTS3 is performed, so that flutter during position registration can be reduced. Therefore, location registration can be performed without imposing an excessive load on the communication processing of the battery of the mobile terminal 11, the femto BTS 3, the macro BTS 5, the RNC 7, and the core network device 9.

  Furthermore, the core network device 9 includes a frequency band changing unit 91f. The frequency band changing unit 91 f changes the mobile terminal 11 whose location is registered for the macro BTS 5 to a different frequency band different from the frequency band currently used by the mobile terminal 11 among the plurality of frequency bands of the macro BTS 5. When the location registration in the change destination frequency band is rejected by the location registration unit 91a, the mobile terminal 11 to which the location registration is rejected is given another frequency band different from the change destination frequency band (for example, Instruct to register the location in the frequency band before change). Therefore, even when the location registration of the mobile terminal 11 with respect to the macro BTS 5 is once permitted by frequency eviction and the bandwidth is allocated and the location registration with respect to the femto BTS 3 is requested, the count value until the previous time of the mobile terminal 11 is held. Therefore, even if the band allocation and the frequency extraction are repeated several times and the count value continues to be incremented, if the count value reaches the threshold value Sr2, the band allocation and the frequency extraction are not performed thereafter, and finally The location registration for femtoBTS3 is permitted, and the flutter at the time of location registration is eliminated. Therefore, location registration can be performed without imposing an excessive load on the communication processing of the battery of the mobile terminal 11, the femto BTS 3, the macro BTS 5, the RNC 7, and the core network device 9.

  DESCRIPTION OF SYMBOLS 1 ... Communication control system, 11 ... Mobile terminal, 3 ... femtoBTS, 3a ... femtoCell, 5 ... macroBTS, 5a ... macroCell, 7 ... RNC, 9 ... Core network apparatus, 91 ... CPU, 91a ... Location registration part, 91b ... Base Station determining unit, 91c ... counting unit, 91d ... registration determining unit, 91e ... rejection number determining unit, 91f ... frequency band changing unit, 92 ... ROM, 93 ... RAM, 94 ... recording device, 95 ... communication device, 96 ... bus .

Claims (3)

A communication control apparatus for controlling location registration of a mobile terminal performed for a first or second radio base station in which both a communication area and a frequency band overlap,
A recording device for recording an identification number of a mobile terminal capable of performing location registration with respect to the first radio base station;
Location registration for performing location registration of a mobile terminal with respect to the first or second radio base station and rejecting location registration with respect to the first radio base station from a mobile terminal whose identification number is not recorded in the recording device Means,
Counting the number of refusals for which location registration was rejected by the location registration means for each mobile terminal, and storing the count value in the recording device;
With
The first radio base station has a smaller communication area than the second radio base station,
The location registration means rejects location registration of the mobile terminal with respect to the first radio base station when the count value is greater than or equal to a first threshold and less than a second threshold greater than the first threshold. At the same time, the first radio base station is instructed to lower the radio field intensity of the first radio base station to a preset intensity, and when the count value reaches the second threshold value, the count value corresponds to the count value. Performing location registration of the mobile terminal with respect to the first radio base station;
The counting unit clears the count value when the location registration with respect to the first radio base station is performed by the location registration unit, and the location registration with respect to the second radio base station is performed by the location registration unit. If the count value is cleared,
A communication control device.   Another frequency band different from the frequency band currently used by the mobile terminal among the plurality of frequency bands of the second radio base station for the mobile terminal whose location is registered with the second radio base station When the location registration in the change destination frequency band is rejected by the location registration means, the mobile terminal performs location registration in another frequency band different from the change destination frequency band. The communication control apparatus according to claim 1, further comprising frequency band changing means for instructing A position registration method in which a communication control apparatus performs position registration of a mobile terminal with respect to a first or second radio base station in which both a communication area and a frequency band overlap.
When receiving a location registration request from the mobile terminal, the communication control apparatus determines whether or not the mobile terminal is registered in advance as a terminal capable of performing location registration with respect to the first radio base station. A first step to:
When the communication control apparatus determines that the mobile terminal is not a terminal capable of performing location registration with respect to the first radio base station in the first step, the communication with respect to the first radio base station is performed. A second step in which the communication control device updates a count value indicating the number of times that the location control of the mobile terminal is rejected by the communication control device and the location registration of the mobile terminal is rejected for the first radio base station;
A third step in which the communication control device holds a count value when the communication control device performs location registration of the mobile terminal with respect to the second radio base station after the second step;
When the location registration request for the first radio base station is made again from the mobile terminal to the communication control device after the third step, the count value is greater than the first threshold value or the first threshold value. A fourth step in which the communication control device determines whether or not a threshold value of 2 is reached ;
When the communication control apparatus determines that the count value is greater than or equal to the first threshold value and less than the second threshold value in the fourth step, the communication control apparatus determines that the first radio base station The first radio base station is instructed to reject the location registration of the mobile terminal and reduce the radio field strength of the first radio base station to a preset strength. In the fourth step, the count value is When the communication control apparatus determines that the threshold value of 2 has been reached, the communication control apparatus clears the count value and permits a location registration of the mobile terminal with respect to the first radio base station; ,
A location registration method comprising:

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