JP4481106B2 - Wireless communication support system and mobile terminal device - Google Patents

Description

  The present invention relates to a wireless communication support system for notifying a mobile terminal apparatus connectable to a plurality of wireless communication systems of available wireless communication systems and the mobile terminal apparatus.

  In recent years, mobile terminal devices (MN: Mobile Node) having a communication function connectable to a plurality of wireless communication systems, for example, cellular, PHS (registered trademark) (Personal Handyphone System), wireless LAN, and the like have been realized. Then, studies are being conducted to enable the MN to move while continuing one communication across the plurality of wireless communication systems by performing handover between the plurality of wireless communication systems.

  For example, in the techniques (prior art 1) described in Non-Patent Documents 1 and 2, a common core network is provided in a plurality of wireless communication systems, and a base station (BS) of each wireless communication system is provided in the core network A resource manager (RM; Resource Manager) having a function of managing the location of the resource is arranged. The MN transmits its location information to the RM at the start of communication. The RM estimates the propagation pattern based on the transmission output of the BS based on the location information received from the MN and the location information of the managed BS, determines a radio communication system that can be used by the MN, A list describing the wireless communication system that can be used at the location of the MN is returned to the MN. Thereby, the MN can select a wireless communication system to be used from the wireless communication systems in the list and start communication.

Further, in the technique described in Non-Patent Document 3 (Prior Art 2), the MN always activates a plurality of wireless devices and constantly monitors the radio wave status of each wireless communication system. Is selected.
Masugi Inoue, Mahamdo Kared, Takashi Murakami, Mikio Hasegawa, “Development of MIRAI Demonstration System (1) Overview”, IEICE Communication Society Conference, September 2002 Takashi Murakami, Mikio Hasegawa, Mahamed Kared, Masugi Inoue, “Development of MIRAI Demonstration System (1) Resource Manager and Signaling Procedure”, IEICE Communication Society Conference, September 2002 Qian Zhang, Chuanxiong Guo, Zihua Guo, Wenwu Zhu, “Efficient mobility management for vertical handoff between WWAN and WLAN”, IEEE Communications Magazine, Nov. 2003.

  However, in the related art 1, the wireless communication system that can be used by the MN is determined from the estimation result of the propagation pattern based on the transmission output of the BS. The estimated propagation area is a circle centered on the BS. It is formed. However, in reality, the propagation area is not necessarily a circle due to the influence of an obstacle such as a building (shadowing, fading, etc.), and is formed in a complicated shape. Accordingly, there is a possibility that some of the available wireless communication systems in the list received by the MN from the RM cannot be actually connected, and the accuracy of the information of the available wireless communication system is poor. . Furthermore, since the location information of the BS is used, the database must be updated immediately in accordance with the BS installation / removal / failure, and the management cost is high. All BSs must have a means for acquiring location information and register their location information in the RM. This is difficult to realize between wireless communication systems managed by different managers.

  Further, in the above-described related art 2, since the MN always activates a plurality of wireless devices and monitors the reception environment, a great problem arises for the MN that power consumption increases and battery life is shortened. In addition, the MN having a software defined radio capable of supporting a plurality of radio communication systems by software using one radio device is not applicable because it can be connected to only one radio communication system at a time.

  The present invention has been made in view of such circumstances, and an object of the present invention is to use an available radio for notifying a mobile terminal device when switching the connection destination of the mobile terminal device in a plurality of radio communication systems. An object of the present invention is to provide a wireless communication support system capable of improving the accuracy of information in a communication system.

  Another object of the present invention is to provide a mobile terminal device applicable to the wireless communication support system of the present invention.

  In order to solve the above problems, a wireless communication support system according to the present invention is a wireless communication support system that notifies a mobile terminal device connectable to a plurality of wireless communication systems of available wireless communication systems. Receiving the location information and the information of the connected wireless communication system from the mobile terminal device, and storing the received location information and the wireless communication system information, and the registered location around the location of the received location information. A search device for searching for a wireless communication system from the database device, creating a usable system list describing information of the discovered wireless communication system, and returning the created usable system list to the mobile terminal device; It is characterized by.

  In the wireless communication support system according to the present invention, the database device receives reception state level information together with the position information and wireless communication system information from the mobile terminal device, and receives the received reception state level information as the position information and wireless information. The information is stored together with communication system information, and the search device includes reception state level information related to the wireless communication system together with the discovered wireless communication system information in the available system list.

  In the wireless communication support system according to the present invention, the database device performs weighted averaging of the received reception state level information, and stores a weighted average value of the reception state level information.

  The wireless communication support system according to the present invention includes a protocol device that transmits and receives a message of an existing communication protocol to and from the mobile terminal device, and the protocol device includes the message in the message received from the mobile terminal device. When the location information and the wireless communication system information are included, the message is transferred to the database device, and the search device includes the available system list in the message and transmits the message to the protocol device. The protocol device transfers the message to the mobile terminal device when the available system list is included in the message received from the search device.

  A mobile terminal device according to the present invention is a mobile terminal device connectable to a plurality of radio communication systems, and includes location information acquisition means for acquiring location information, and information on the acquired location information and a connected radio communication system Transmitting means to the registration destination, receiving means for receiving an available system list in which information of available wireless communication systems is described, and storage means for storing the received available system list It is characterized by that.

  The mobile terminal device according to the present invention is characterized by comprising display means for displaying information of the wireless communication system in the stored available system list.

  The mobile terminal apparatus according to the present invention comprises control means for selecting a radio communication system to switch connection according to a predetermined priority based on information of the radio communication system in the stored available system list. It is characterized by.

  In the mobile terminal apparatus according to the present invention, the mobile terminal apparatus includes measurement means for measuring reception state level information related to a connected wireless communication system, and the transmission means includes the measured reception together with the position information and the wireless communication system information. State level information is transmitted to the registration destination.

  In the mobile terminal apparatus according to the present invention, the transmission unit transmits the existing communication protocol message including the location information and the wireless communication system information, and the reception unit includes the available system list. The message is received.

  The mobile terminal device according to the present invention further includes a movement speed calculation unit that calculates a movement speed based on the acquired position information, and the transmission unit transmits to the registration destination at a frequency according to the calculated movement speed. It is characterized by doing.

  According to the present invention, the location information managed by the database device and the information of the wireless communication system that can be connected at the location are updated as needed based on the location information of the mobile terminal device and the information of the wireless communication system currently connected at the location. Therefore, a wireless communication system that can be used in accordance with the actual wireless environment at each position is registered in the database device. Since a list of available wireless communication systems corresponding to the position of the mobile terminal device is created based on the stored information of the database device and provided to the mobile terminal device, the mobile terminal among a plurality of wireless communication systems When switching the connection destination of the device, it is possible to improve the accuracy of the information of the available wireless communication system notified to the mobile terminal device. As a result, the mobile terminal apparatus can smoothly perform inter-system handover.

Hereinafter, embodiments of the present invention will be sequentially described with reference to the drawings.
[First Embodiment]
FIG. 1 is a block diagram showing a configuration of a wireless communication support system according to the first embodiment of the present invention. In FIG. 1, a mobile terminal device (MN; Mobile Node) 10 has a communication function that can be connected to a plurality of wireless communication systems (WCS-A, B, C) 30, 40, and 50.

  The wireless communication system (WCS-A) 30 is a cellular system having a wide service area, for example. The wireless communication systems (WCS-B, C) 40 and 50 have a smaller service area than WCS-A_30. WCS-B_40 is, for example, PHS (registered trademark) or wireless MAN (Metropolitan Area Network). WCS-C_50 is, for example, a wireless LAN. And as FIG. 1 shows, WCS-B_40 and WCS-C_50 are overlaid with respect to WCS-A_30.

  The WCS-A_30 includes a base station (BS) 31. WCS-B_40 includes BS_41. WCS-C_50 includes BS_51. Each BS_31, 41, 51 is connected to the core network 70.

  The core network 70 is a network common to the WCS-A, B, C_30, 40, and 50. The core network 70 is provided with a location information and applied system information data base (LAS-DB) 71 and a search device 72. The search device 72 can access the LAS-DB 71 and perform data search.

  The MN 10 is connected to the core network 70 via the WCS-A, B, C_30, 40, and 50, and can access the LAS-DB 71 and the search device 72.

  WCS-A, B, C_30, 40, and 50 may be systems of different communication carriers. Further, the LAS-DB 71 and the search device 72 may be provided in any one of the WCS-A, B, C_30, 40, and 50 systems. In this case, the WCS-A, B, C_30, 40, and 50 are connected by a public network such as the Internet or a dedicated line so that the LAS-DB 71 and the search device 72 can be accessed from any WCS.

FIG. 2 is a block diagram showing a configuration of the MN 10 shown in FIG.
In FIG. 2, a radio unit 11 transmits and receives radio signals to and from BSs 31, 41, and 51 via an antenna, and performs a voice call or data communication. The wireless environment measuring unit 12 measures a wireless environment such as received radio wave intensity. The control unit 13 controls each unit of the MN 10 and performs a control process for switching the connection destination wireless communication system. The storage unit 14 is accessed from the control unit 13 and stores various data. The operation unit 15 has input devices such as a numeric keypad and various function keys, and outputs input data to the control unit 13. The display unit 16 includes a display device such as a liquid crystal panel, and displays display data input from the control unit 13. The microphone 17 performs voice input during a call. The speaker 18 outputs sound during a call. A GPS (Global Positioning System) unit 19 detects transmission radio waves from an artificial satellite and obtains position information indicating the current position of the MN 10.

  The control unit 13 periodically notifies the LAS-DB 71 of the position information acquired by the GPS unit 19 and information (identifier etc.) of the currently connected wireless communication system.

FIG. 3 is a diagram showing a configuration example of the management table 101 provided in the LAS-DB 71 shown in FIG.
In the management table 101, position information and wireless communication system information (identifiers, etc.) notified from the MN 10 are registered. In FIG. 3, the management table 101 has an individual table for storing information of the wireless communication system to which the MN 10 is connected at the position for each position information (latitude, longitude, altitude). The individual table is provided with a timer for each wireless communication system. When newly registering each individual table, a timer is set and started. Then, the individual table that has timed out is deleted. On the other hand, when the registered wireless communication system information related to the registered position information is received before the timeout, the timer of the corresponding individual table is restarted after resetting. If the received wireless communication system information is not registered in the existing individual table, the wireless communication system information is added. The initial value of the timer is preset by the carrier.

Next, an operation according to the first embodiment of the present invention will be described with reference to FIG. FIG. 4 is a sequence diagram according to the first embodiment of the present invention.
In FIG. 4, the MN 10 periodically transmits the current location information and information of the currently connected wireless communication system to the LAS-DB 71 (step S1). When receiving the location information and the wireless communication system information, the LAS-DB 71 authenticates the MN 10 and updates the management table 101 based on the received information if the authentication is successful (step S2). Next, the search device 72 searches the registered wireless communication system around the location of the received location information from the management table 101 of the LAS-DB 71, and obtains an available system list describing the information of the discovered wireless communication system. Create (step S3). As a result, the available system list describes information on the wireless communication system that can be used around the position of the MN 10 that transmitted the position information and the wireless communication system information. Next, the search device 72 returns the created available system list to the MN 10 (step S4).

  Next, the MN 10 stores the received available system list in the storage unit 14 and displays the wireless communication system information in the available system list on the display unit 16. Accordingly, the user of the MN 10 can select a desired wireless communication system from the displayed available wireless communication systems and instruct a switching destination. Upon receiving this instruction, the MN 10 performs handover to the instructed wireless communication system (step S5).

  According to the first embodiment described above, the management table 101 of the LAS-DB 71 is updated at any time with the location information of the MN 10 and the information of the wireless communication system connected at the location. An available wireless communication system that matches the actual wireless environment is registered. Then, a list of available wireless communication systems corresponding to the position of the MN 10 is created based on the management table 101, and the list is provided to the MN 10. Therefore, when switching the connection destination of the MN 10 among a plurality of wireless communication systems In addition, it is possible to improve the accuracy of the information of the available wireless communication system notified to the MN 10. As a result, the MN 10 can smoothly perform handover between systems.

  In addition, since the MN 10 only needs to monitor the radio wave condition of the connected wireless communication system, it can cope with software radio.

  Note that the MN 10 may register WCS-A_30 having a wide service area as a default connection destination and normally connect to the WCS-A_30. In this case, if the MN 10 includes a wireless device for each WCS-A, B, C_30, 40, and 50, the wireless device for WCS-B, C_40, and 50 is normally set in a standby state. Note that the wireless device for WCS-A_30 may be always active.

  Further, the MN 10 may automatically select a switching destination from the available system list in accordance with preset priority information. Also, it may be determined whether to switch or maintain the current connection. The priority information is information indicating the priority order of connection destinations. For example, when both the PHS (registered trademark) and the wireless LAN can be used, the wireless LAN is preferentially selected.

Also, if the MN 10 has a wireless device for each WCS-A, B, C_30, 40, 50, before switching the connection destination, the wireless device of the switching destination wireless communication system is made active. Search for wireless environment such as radio field strength to see if it is actually possible to receive communication services. As a result, when the communication service can be actually received, inter-system handover is performed. On the other hand, when the communication service cannot be actually received due to the update time lag of the management table 101 of the LAS-DB 71 described above, the MN 10 informs the LAS-DB 71 that the wireless communication system cannot be used together with the location information. Notice. Thereby, the management table 101 of the LAS-DB 71 is updated.
Based on the search result of the wireless environment, a threshold value such as a radio wave state for determining to switch the connection destination system is set in advance.

  In addition, when the MN 10 leaves the service area of the wireless communication system with a narrow service area like the MN-2_10 in FIG. 1, the connection destination system is switched based on the radio wave condition of the connected wireless communication system. It may be determined whether or not. In other words, when the radio wave condition in the currently connected wireless communication system has deteriorated, a preliminary investigation of handover to the wireless communication system in the default wireless communication system or the available system list (activation of the wireless device and wireless communication) Environment search, etc.) and perform handover based on the result of this investigation.

  In the LAS-DB 71, when registering the location information of the MN 10 in the management table 101, for example, the latitude and longitude “seconds” may be rounded and registered. Alternatively, it may be converted into a hash value and registered. As a result, the load on the search of the management table 101 is reduced, and the search time can be shortened.

[Second Embodiment]
In the second embodiment, the LAS-DB 71 of the first embodiment includes the management table 201 shown in FIG. In the management table 201 of FIG. 5, information on the level of the reception state of the wireless communication system is added to the management table 101 of FIG. This reception state level information is a reception intensity level such as CIR (Carrier to Interference Ratio) at a certain position of the wireless communication system. In the example of FIG. 5, the reception intensity is divided into 8 levels.

  The MN 10 periodically transmits to the LAS-DB 71 information on the reception state level measured by the identifier of the currently connected wireless communication system and the wireless environment measuring unit 12 together with the current position information. Based on the information from the MN 10, the LAS-DB 71 updates the management table 201. At the time of this update, an average of the reception state level value already registered in the management table 201 and the newly notified reception state level value is taken as an update value. The average value is preferably a weighted average value. The reason for this is that information that is more suitable for the actual wireless environment can be obtained by setting the new value to a greater weight over time.

  Then, based on the search result of the management table 201, the search device 72 describes the identifier of the available wireless communication system and the reception state level information in the available system list.

  As a result, in a MN that cannot access two wireless communication systems at the same time (for example, a MN that implements only software defined radio), the reception state level information in the available system list is preset when performing inter-system handover. It is possible to ensure communication quality by comparing the received threshold value and performing a handover to a radio communication system having a reception state level equal to or higher than the threshold value.

[Third Embodiment]
In the third embodiment, the frequency at which the MN 10 notifies the LAS-DB 71 of the position information and the wireless communication system information is changed according to its own moving speed.
In the MN 10 of FIG. 2, the control unit 13 calculates the moving speed of the MN 10 based on the position information acquired by the GPS unit 19. When the moving speed of the MN 10 is v kilometers per hour, the notification frequency is α * v times per second. α is a parameter that can be determined by the service provider.

  As a result, the wireless environment is likely to change significantly during high-speed movement, so the notification frequency can be increased and information corresponding to the change in the wireless environment can be immediately notified to the LAS-DB 71 and reflected in the management table. . On the other hand, during low-speed movement, there is a low possibility that the radio environment will change greatly, and there may be cases where the LAS-DB 71 does not become effective even when frequently notified. For this reason, at low speed, the notification frequency is reduced to reduce the load on the network and the LAS-DB 71.

  In addition, when the moving speed is equal to or higher than a preset value, the control unit 13 may not perform inter-system handover that switches the connection destination to a specific wireless communication system. This prevents connection to a wireless communication system that cannot follow the MN 10 moving at high speed.

[Fourth Embodiment]
In the fourth embodiment, a message used in an existing communication protocol such as a mobility protocol is used to exchange information between the MN 10, the LAS-DB 71, and the search device 72.
For example, “Mobile IP” is known as a mobility protocol. With “Mobile IP”, the MN 10 manages the IP address of the MN 10 with the HA by notifying the HA (Home Agent) of the IP address of the destination using BU (Binding Update). Also, when HA receives BU from MN 10, it returns BAck to MN 10. Hereinafter, a case where BU and BAck used in “Mobile IP” are used will be described as an example.

  FIG. 6 is a block diagram showing a configuration of a wireless communication support system according to the fourth embodiment of the present invention. In FIG. 6, the HA 81 is provided in the core network 70 with respect to the wireless communication support system of FIG. The HA 81, the LAS-DB 71, and the search device 72 are preferably provided in the same domain.

  FIG. 7 is a diagram illustrating a configuration example of a BU used in the wireless communication support system according to the fourth embodiment of the present invention. In FIG. 7, the message data field of BU is expanded, and a field for storing position information (latitude, longitude, altitude) of the MN 10 and a field (Applied System) for storing information of the connected wireless communication system are provided. Yes. Then, one of the reserved bits of the BU is used as a G (Geographical Information) flag to clearly indicate that the information addressed to the LAS-DB 71 is included in the BU. That is, when notifying position information and wireless communication system information to the LAS-DB 71, the control unit 13 of the MN 10 stores the position information and wireless communication system information in the BU, and turns on the G flag of the BU.

  FIG. 8 is a diagram illustrating a configuration example of BAck used in the wireless communication support system according to the fourth embodiment of the present invention. In FIG. 8, the message data field of BAck is expanded, and a field (Available System List) for storing an available system list created by the search device 72 is provided. Then, one of the reserved bits of BAck is used as an A (Available System List) flag to clearly indicate that the information addressed to MN 10 is included in BAck. That is, when transmitting the available system list to the MN 10, the search device 72 stores the available system list in BAck and turns on the A flag of the BAck.

Next, with reference to FIG. 9, the operation | movement which concerns on the 4th Embodiment of this invention is demonstrated. FIG. 9 is a sequence diagram according to the fourth embodiment of the present invention.
In FIG. 9, the MN 10 stores the current location information and information of the currently connected wireless communication system in the BU and turns on the G flag to transmit the BU to the HA 81 (step S11). This BU is received by the HA 81. The HA 81 checks the G flag of the received BU. If the G flag is ON, the HA 81 transfers the BU to the LAS-DB 71 (step S12). Next, when receiving the transferred BU, the LAS-DB 71 acquires position information and wireless communication system information from the BU, and updates the management table 101 in the same manner as in step S2 in FIG. 4 (step S13). .

  Next, the search device 72 creates an available system list in the same manner as in step S3 of FIG. 4 (step S14), stores the available system list in BAck, turns on the A flag, and sets the BAck to HA81. (Step S15). This BAck is received by the HA 81. The HA 81 checks the A flag of the received BAck, and if the A flag is ON, transfers the BAck to the corresponding MN 10 (step S16). Next, when the MN 10 receives the transferred BAck, the MN 10 obtains an available system list from the received BAck and performs a handover process (step S17).

  According to the fourth embodiment described above, since a message of an existing communication protocol can be used, a system according to the present invention can be constructed with only a small overhead with respect to an existing system.

  Note that a signaling protocol such as SIP (Session Initiation Protocol) may be used as an existing communication protocol. For example, when SIP is used, the LAS-DB 71 is arranged in the vicinity of the location server or the SIP proxy, for example, SIP signaling data such as “REGISTER” is expanded, and information between the MN 10 and the LAS-DB 71 and the search device 72 is transmitted. Use for communication.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design changes and the like within a scope not departing from the gist of the present invention.

1 is a block diagram illustrating a configuration of a wireless communication support system according to a first embodiment of the present invention. It is a block diagram which shows the structure of MN10 shown in FIG. It is a figure which shows the structural example of the management table 101 with which LAS-DB71 shown in FIG. 1 is equipped. It is a sequence diagram concerning the 1st embodiment of the present invention. It is a figure which shows the structural example of the management table 201 which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the radio | wireless communication assistance system which concerns on the 4th Embodiment of this invention. It is a figure which shows the structural example of BU used with the radio | wireless communication assistance system which concerns on the 4th Embodiment of this invention. It is a figure which shows the structural example of BAck used with the radio | wireless communication assistance system which concerns on the 4th Embodiment of this invention. It is a sequence diagram concerning a 4th embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Mobile terminal device (MN), 11 ... Radio | wireless part, 12 ... Wireless environment measurement part, 13 ... Control part, 14 ... Memory | storage part, 15 ... Operation part, 16 ... Display part, 19 ... GPS (position information acquisition means) , 30, 40, 50 ... wireless communication system (WCS-A, B, C), 31, 41, 51 ... base station (BS), 70 ... core network, 71 ... LAS-DB, 72 ... search device, 101, 201 ... management table.

Claims (12)

A wireless communication support system for notifying a mobile terminal device connectable to a plurality of wireless communication systems of available wireless communication systems,
A database device that periodically receives location information and information of a connected wireless communication system from the mobile terminal device, and stores the received location information and wireless communication system information;
The wireless communication system registered at the position around the received positional information retrieved from said database device, create an available system list described the discovery information of the wireless communication system, the available system list created, the A search device that replies to the mobile terminal device as a response to the location information and wireless communication system information received by the database device ;
A wireless communication support system comprising: The database device receives reception state level information together with the position information and wireless communication system information from the mobile terminal device, stores the received reception state level information together with the position information and wireless communication system information,
2. The wireless communication support system according to claim 1, wherein the search apparatus includes reception state level information related to the wireless communication system together with information of the discovered wireless communication system in the available system list.   The wireless communication support system according to claim 2, wherein the database device performs weighted averaging of the received reception state level information and stores a weighted average value of the reception state level information. A protocol device for transmitting and receiving an existing communication protocol message to and from the mobile terminal device;
The protocol device, when the location information and wireless communication system information are included in the message received from the mobile terminal device, transfers the message to the database device,
The search device includes the available system list in the message and transmits the message to the protocol device,
2. The wireless communication support according to claim 1, wherein when the available system list is included in a message received from the search device, the protocol device transfers the message to the mobile terminal device. system. A mobile terminal device connectable to a plurality of wireless communication systems,
Position information acquisition means for acquiring position information;
Periodically, a transmission means for transmitting the acquired location information and information of the connected wireless communication system to a registration destination;
Receiving means for receiving an available system list in which information of available wireless communication systems is described as a response to the location information and wireless communication system information transmitted to the registration destination ;
Storage means for storing the received available system list;
A mobile terminal device comprising:   6. The mobile terminal apparatus according to claim 5, further comprising display means for displaying information on the wireless communication system in the stored available system list.   6. The control unit according to claim 5, further comprising: a control unit that selects a radio communication system to switch connection according to a predetermined priority based on information of the radio communication system in the stored available system list. Mobile terminal device. Comprising measuring means for measuring reception state level information relating to the connected wireless communication system;
The mobile terminal apparatus according to claim 5, wherein the transmission unit transmits the measured reception state level information to the registration destination together with the position information and wireless communication system information. The transmitting means transmits the existing communication protocol message including the position information and wireless communication system information,
The mobile terminal apparatus according to claim 5, wherein the receiving unit receives the message including the available system list. A moving speed calculating means for calculating a moving speed based on the acquired position information;
The mobile terminal apparatus according to claim 5, wherein the transmission unit transmits the registration destination to the registration destination at a frequency according to the calculated moving speed. The database device includes:
Information on the unavailability of the wireless communication system based on a wireless environment search result by the mobile terminal device for the wireless communication system described in the available system list returned from the search device to the mobile terminal device is stored in the mobile terminal device. Receiving from the mobile terminal device together with the location information, and updating the location information and the wireless communication system information stored in the own database device based on the received location information and information on the unavailability of the wireless communication system,
The wireless communication support system according to claim 1. A wireless environment search means for searching a wireless environment of each wireless communication system described in the received available system list;
A wireless communication system availability determination means for determining availability of each wireless communication system based on a wireless environment search result of each wireless communication system;
An available system list response means for transmitting information on a wireless communication system that is not usable by the determination together with the acquired location information to the registration destination;
The mobile terminal apparatus according to claim 5, further comprising:

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