JP4777384B2 - switch - Google Patents

Description

The present invention includes, for example, a mobile terminal, a home base station or roaming base station that can accommodate and connect the mobile terminal, and a private branch exchange that accommodates and connects the home base station, and is particularly accommodated and connected to the private branch exchange. The present invention relates to an exchange capable of recognizing the position of a mobile terminal from a terminal with a display function.

Conventionally, as such a wireless communication system, the following technique is known (see Patent Document 1).
Japanese Patent No. 3157443

  The wireless communication system includes a mobile terminal, a base station that accommodates and connects the mobile terminal, and a center station that connects to the base station. The center station inputs a mobile terminal number that identifies the mobile terminal. The base station that accommodates and connects the mobile station corresponding to the mobile terminal number is detected, and the position of the mobile terminal is displayed on the display unit of the center station based on the base station.

  However, according to the conventional wireless communication system, when the mobile terminal moves from the home base station to an out-of-service base station, that is, a roaming base station, the center station does not support the roaming base station. The position of the mobile terminal cannot be recognized.

The present invention has been made in view of the above points, and an object thereof is to provide an exchange capable of recognizing the position of a mobile terminal even when the mobile terminal moves from a home base station to a roaming base station. There is to do.

Exchange of the present invention in order to achieve the above object, a base station that wirelessly connects with the mobile terminals, a switch that accommodates a display function terminal, a mobile terminal number of said mobile terminal, said A BS number for identifying a roaming base station other than the base station or the base station and storing an associated BS number identifying a roaming base station other than the base station or the base station that is accommodating the mobile terminal Storage means for associating and storing at least one of the BS accommodating position of the roaming base station other than the base station or the base station or the BS name of the roaming base station other than the base station or the base station ; From the terminal with display function, the mobile terminal number of the mobile terminal subject to location search and the location search special number for normal incoming call or the location search special number for ringing incoming call are received. When the received mobile terminal number is identified, the accommodated BS number is identified, and the call operation by the normal incoming call or the ringing incoming call according to the received location search special number is performed, the call corresponding to the identified accommodated BS number A control unit that executes the location search target mobile terminal via a base station or the roaming base station, and a response to the call operation from the location search target mobile terminal; When the BS name is stored in the storage means in association with the BS number corresponding to the accommodated BS number, the BS name corresponding to the identified accommodated BS number is displayed on the display unit of the terminal with display function together make, in a case where there is a response to the call operation from the position searched mobile terminal, the receiving BS number identified If the BS name is not stored in the storage means in association with the corresponding BS number, and the BS accommodation position is stored in association with the BS number corresponding to the identified accommodation BS number, and so and a display control means for displaying the BS receiving position corresponding to the accommodating BS number on the display portion of the display function terminal.

Therefore, according to the exchange of the present invention, when the location search special number from the terminal with display function is detected and the mobile terminal number from the terminal with display function is detected, the mobile terminal corresponding to this mobile terminal number is roaming base station If the mobile terminal is determined to be accommodated and connected to the roaming base station, identification information corresponding to the roaming base station is displayed on the display unit of the terminal with a display function. Therefore, even if the user of the terminal with a display function specifies a mobile terminal to be searched for position by a simple operation and the specified mobile terminal is accommodated and connected to the roaming base station, the roaming base station By displaying this identification information, it is possible to recognize this roaming base station as the current position of the mobile terminal.

In the exchange according to the present invention, when the control unit receives a location search special number for normal incoming call from the terminal with display function, the call operation is performed so that an incoming history remains in the mobile terminal subject to location search When a location search special number for a ringing incoming call is received from the terminal with display function, the call operation can be executed so that no incoming call history remains in the location search target mobile terminal .

Therefore, according to the exchange of the present invention, since the identification information stored in the storage means is the accommodation position number or name data for identifying the home base station or roaming base station, the user of the terminal with a display function can perform a simple operation. The mobile terminal that is the location search target is identified by the roaming base station by displaying the name data and the accommodating position number of the roaming base station even if the identified mobile terminal is accommodated and connected to the roaming base station. Can be recognized as the current location of the mobile terminal.

  According to the present invention, when a location search special number from a terminal with a display function is detected and a mobile terminal number from the terminal with a display function is detected, the mobile terminal corresponding to the mobile terminal number is accommodated and connected to the roaming base station. If the mobile terminal is determined to be accommodated and connected to the roaming base station, identification information corresponding to the roaming base station is displayed on the display unit of the terminal with a display function. Therefore, the user of the terminal with a display function specifies a mobile terminal that is a location search target by a simple operation, and even if the specified mobile terminal is accommodated and connected to the roaming base station, the identification information of the roaming base station is displayed. By displaying, this roaming base station can be recognized as the current position of the mobile terminal.

  A private wireless communication system showing an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration inside a private wireless communication system according to the present embodiment.

  A private wireless communication system 1 shown in FIG. 1 includes a private branch exchange (hereinafter simply referred to as a home station PBX) 1A, a plurality of mobile terminals (hereinafter simply referred to as PS) 2, and a home base station wirelessly connected to the PS2. 3A (hereinafter simply referred to as home BS). It is assumed that the local wireless communication system 1 has home BSs 3A for each department in a company facility, for example.

  The home station PBX 1A communicates with a base station interface (hereinafter simply referred to as a BS interface) 4 that communicates with the home BS 3A, a multi-function telephone (hereinafter simply referred to as MFT) 5 having a display function, and a communication connection with the MFT 5 An extension trunk (hereinafter simply referred to as LIN) 6, a local line interface (hereinafter simply referred to as COT) 8 for communication connection with the public network 1 D, a control terminal 9, and an ISDN extension for communication connection with the control terminal 9 A communication path switch (hereinafter simply referred to as TSW) 12 that forms a communication path between the interface 10, the BS interface 4, the LIN 6, the COT 8, and the ISDN extension interface 10; a memory 13 that stores various data and the like; A central control device (hereinafter simply referred to as CPE) that controls the entire private wireless communication system 1. ) And a 14. It is assumed that the communication sequence between PS2 and home BS3A and home station PBX1A is performed according to a communication sequence standardized by TTC standard-Q931-1a.

  The MFT 5 includes a dial operation unit and a display unit that displays various information such as a BS name and a BS accommodating position on the screen.

  FIG. 2 is an explanatory diagram briefly showing the memory contents of the memory 13.

  In FIG. 2, a memory 13 includes a mobile terminal identification number (hereinafter simply referred to as PS number) 21 for identifying PS2, and a home BS 3A or roaming base station (visitor base station, hereinafter simply referred to as roaming BS) that accommodates PS2. The storage BS number 22 indicating the BS number of 3B and the determination flag 23 indicating whether the PS2 is connected to the home BS 3A or the roaming BS 3B are stored for each PS2.

  Further, the memory 13 includes a BS number 24 for identifying the home BS 3A or the roaming BS 3B, a BS accommodation position 25 indicating the accommodation position of the home BS 3A or the roaming BS 3B, and a BS name 26 indicating the name of the home BS 3A or the roaming BS 3B. Remember every time.

  Further, the memory 13 stores a position search special number for normal incoming calls and a position search special number for ringing incoming calls. Note that the position search special number for normal incoming calls is to execute a position search by making a normal incoming call to the PS2 that is the position search target, and the incoming call history remains in the position search target PS2 according to the normal call. On the other hand, the position search special number for the ringing incoming call executes the position search by placing the ringing incoming call on the PS2 as the position search target, and the PS2 as the position search target responds to the ringing incoming call. No incoming call history will remain.

  FIG. 3 is a block diagram showing a schematic configuration inside the CPE 14.

  The CPE 14 detects a PS number for identifying the PS2 of the position search target from the MFT 5 when the special search unit 31 for detecting the position search special number from the MFT 5 and the position search special number by the special number detection unit 31 are detected. When the PS number is detected by the number detecting unit 32 and the PS number detecting unit 32, whether or not PS2 corresponding to this PS number is accommodated and connected to the roaming BS 3B based on the determination flag 23 stored in the memory 13 If the roaming determination unit 33 determines that the PS2 is accommodated and connected to the roaming BS 3B, the BS name 26 corresponding to the roaming BS 3B is displayed on the display unit of the MFT 5 At the same time, when the roaming determination unit 33 determines that PS2 is not accommodated and connected to the roaming BS 3B, Control that determines that S2 is accommodated and connected is the home BS 3A, and displays the BS name 26 or BS accommodating position 25 corresponding to the home BS 3A on the display unit of the MFT 5, and control for controlling the entire CPE 14 Part 35.

  FIG. 4 is an explanatory diagram simply showing the display contents of the display unit of the MFT 5.

  When the BS name 26 of the BS 3 that accommodates and connects the position search target PS 2 is in the memory 13 in the PS position search display processing described later, the MFT 5, as shown in FIG. The BS name 41 of the BS 3 that accommodates and connects, the PS number 42 of the PS 2 that is the position search target, the current date and time 43, and the extension number 44 of the MFT 5 are displayed on the display unit.

  The MFT 5 does not have the BS name 26 of the BS 3 that accommodates and connects the PS 2 that is the location search target in the PS location search display process, but when there is the BS accommodation location 25, as shown in FIG. The BS accommodating position 45 of the BS 3 that accommodates and connects the PS 2, the PS number 42 of the PS 2 to be searched for the position, the current date and time 43, and the extension number 44 of the MFT 5 are displayed on the display unit.

  When there is no BS accommodation position 25 or BS name 26 of the BS 3 that accommodates and connects the position search target PS2 in the PS position search display processing, the MFT 5 displays the position search target PS2 as shown in FIG. The out-of-service area 46 indicating the out-of-service area, the PS number 42 of the PS 2 as the position search target, the current date and time 43, and the extension number 44 of the MFT 5 are displayed on the display unit.

  In addition, when there is a BS name 26 of the BS 3 that accommodates and connects the PS 2 that is talking in the later-described call PS location search display process, the MFT 5 accommodates and connects the PS 2 that is talking as shown in FIG. The BS name 41 of the BS 3, the PS number 42 of the PS 2 during the call, the current date and time 43, and the extension number 44 of the MFT 5 are displayed on the display unit.

  Further, the control terminal 9 corresponds to, for example, a personal computer or the like, specifies the PS 2 as a position search target according to a special operation, and controls the current position of the PS 2 by the BS name 26 of the BS 3 that accommodates and connects the specified PS 2 9 is displayed on the screen.

  The terminal with a display function described in the claims is MFT5, the storage means is the memory 13, the special number detection means is the special number detection section 31, the mobile terminal number detection means is the PS number detection section 32, the roaming determination means is the roaming determination section 33, the display The control means corresponds to the display control unit 34.

  Next, the operation of the private wireless communication system 1 showing the present embodiment will be described. FIG. 5 is a flowchart showing the processing operation of the CPE 14 related to the PS position search display processing related to the present embodiment.

  The PS position search display process shown in FIG. 5 is to specify a PS2 as a position search target in accordance with a special operation from the MFT 5 and to specify a BS3 that accommodates and connects this PS2, so that the BS name of the BS3 and the BS In this process, the accommodation position is displayed on the display unit of the MFT 5 as position information of the PS2.

  In FIG. 5, the CPE 14 determines whether or not a location search special number and a PS number have been received from the MFT 5 (step S11). When the control unit 35 of the CPE 14 detects the position search special number from the MFT 5 through the special number detection unit 31, the PS position search display process is started, and on the basis of the detected position search special number, a ringing incoming call or a normal incoming call is received. The incoming call form is selected. Further, when the control unit 35 detects the PS number from the MFT 5 through the PS number detection unit 32, the control unit 35 specifies the PS 2 as a position search target.

  If the CPE 14 receives the position search special number and the PS number from the MFT 5, the CPE 14 reads the determination flag 23 corresponding to the PS number stored in the memory 13, and the position search target corresponding to the PS number based on the determination flag 23. It is determined whether or not the PS2 is accommodated and connected to the home BS 3A (step S12).

  When it is determined that the location search target PS2 is accommodated and connected to the home BS 3A, the CPE 14 starts a call operation on the location search target PS2 in the incoming call form selected by the location search special number in step S11. (Step S13).

  When starting the calling operation, the CPE 14 starts a home PS calling timer (step S14), and determines whether or not there is a response from the PS2 (step S15). Note that the response from PS2 corresponds to a response such as call acceptance information from PS2 to the setup information from home BS 3A to PS2, for example.

  When the CPE 14 determines that there is a response from the PS 2, the CPE 14 determines whether or not the BS name 26 of the home BS 3A that has received this response is in the memory 13 (step S16).

  When the CPE 14 determines that the BS name 26 of the home BS 3A is in the memory 13, the CPE 14 reads the BS name 26 from the memory 13 (step S17), and sets the read BS name 26 as the current position of the PS 2 as shown in FIG. As shown to (a), it displays on the display part of MFT5 (step S18), and this processing operation is complete | finished. Note that the user of the MFT 5 can recognize the current position of the position search target PS2 based on the BS name being displayed.

  If it is determined in step S16 that the BS name 26 of the home BS 3A is not in the memory 13, the BS accommodation position 25 of the home BS 3A is read from the memory 13 (step S19), and as shown in FIG. The BS accommodation position 25 of the home BS 3A is displayed on the display unit of the MFT 5 (step S20), and this processing operation is terminated. Note that the user of the MFT 5 can recognize the current position of the PS 2 as a position search target based on the BS accommodation position being displayed.

  If it is determined in step S15 that there is no response from PS2, the CPE 14 determines whether or not the home PS call timer started in step S14 has timed out (step S21). If the home PS call timer has not timed out, the process proceeds to step S15 in order to monitor the response from PS2.

  If the home PS call timer has timed out in step S21, it is determined that there is no response from this PS2 within this call timer time, this PS2 is determined to be out of range, and the MFT5 display section indicates that it is out of range. This is displayed (step S22), and this processing operation is terminated. Note that the user of the MFT 5 can recognize that the current position of the PS 2 that is the position search target is out of service area by displaying the out-of-service area being displayed.

  If it is determined in step S12 that PS2 is not accommodated and connected to home BS 3A, that is, if it is determined that PS2 is accommodated and connected to roaming BS 3B, CPE 14 calls PS2 through this roaming BS 3B. The operation is started (step S23).

  When the CPE 14 starts a call operation to PS2, the CPE 14 starts a roaming PS call timer (step S24), and determines whether there is a response from PS2 to the roaming BS 3B (step S25).

  When it is determined that there is a response from PS2, the CPE 14 determines whether or not the BS name 26 corresponding to the roaming BS 3B exists in the memory 13 (step S26).

  When the CPE 14 determines that the BS name 26 corresponding to the roaming BS 3B exists in the memory 13, the CPE 14 reads the BS name 26 (step S27) and displays the BS name 26 on the display unit of the MFT 5 (step S28). This processing operation ends. Note that the user of the MFT 5 can recognize the current position of the PS 2 based on the BS name 26 being displayed even if the PS 2 as a position search target is being accommodated and connected to the roaming BS 3B.

  If it is determined in step S25 that there is no response from PS2, CPE 14 determines whether or not the roaming PS call timer has expired (step S29).

  If the roaming PS call timer has not timed out, the CPE 14 proceeds to step S25 to monitor the response from PS2.

  If it is determined in step S29 that the roaming PS call timer has timed up, or if it is determined in step S26 that the BS name 26 corresponding to the roaming BS 3B is not in the memory 13, the CPE 14 Is determined to be out of service area, the service area is displayed on the display unit of the MFT 5 (step S30), and this processing operation is terminated. Note that the user of the MFT 5 can recognize that the current position of the PS 2 that is the position search target is out of service area by displaying the out-of-service area being displayed.

  According to the PS location search display process shown in FIG. 5, just by inputting the location search special number and the location search target PS number from the MFT 5, the BS name 26 of the BS 3 accommodating and connecting the location search target PS2 and the BS location 25 is displayed on the display unit of MFT5 as the current position of PS2, so that even if PS2 is accommodated and connected to home BS 3A or roaming BS 3B, the user of MFT 5 recognizes the current position of PS 2 with a simple dial operation. can do.

  Further, according to the PS position search display processing, the position search special number from the MFT 5 is detected, and the normal incoming call type or the non-ring incoming type is selected according to the position search special number. Then, the current position of PS2 can be specified by making an incoming call to PS2 without noticing the user of PS2 that is the position search target. In PS2, in the case of a ringing incoming call, no incoming call history corresponding to the ringing incoming call is left.

  FIG. 6 is a flowchart showing the processing operation of the CPE 14 related to the call PS position search display process.

  The call PS location search display process shown in FIG. 6 specifies the BS name 26 and BS accommodation location 25 of this BS 3 by specifying the BS 3 accommodating and connecting this PS 2 when the MFT 5 makes a call with the PS 2. Is displayed on the display unit of the MFT 5.

  In FIG. 6, the CPE 14 determines whether or not the PS number of PS2 is received from the MFT 5 (step S41). If it is determined that the PS number of the PS 2 has been received, the CPE 14 determines whether or not the PS 2 corresponding to this PS number is accommodated and connected to the home BS 3A based on the PS number determination flag 23 (step S42).

  When the CPE 14 determines that the PS2 corresponding to the PS number is accommodated and connected to the home BS 3A, the CPE 14 starts a ringing operation with a normal incoming call to the PS 2 (step S43), and a response from the PS 2 through the home BS 3A. It is determined whether or not there has been (step S44).

  If it is determined that there is a response from PS2, the CPE 14 determines whether or not the BS name 26 corresponding to this PS2 exists in the memory 13 (step S45). When the CPE 14 determines that the BS name 26 is in the memory 13, the CPE 14 reads the BS name 26 from the memory 13 (step S46), and as shown in FIG. The information is displayed on the display unit (step S47), and this processing operation is terminated. Note that the user of the MFT 5 can recognize the current position of the PS 2 that is the other party based on the BS name 26 being displayed.

  If there is no response from PS2 in step S44, the CPE 14 ends this processing operation. If the BS name 26 of the home BS 3A is not in the memory 13 in step S45, the CPE 14 reads the BS accommodating position 25 of the home BS 3A from the memory 13 (step S48), and reads the read BS accommodating position 25 to the MFT 5 Are displayed on the display unit (step S49), and this processing operation is terminated. Note that the user of the MFT 5 can recognize the current position of the PS 2 that is the call partner based on the BS accommodation position 25 being displayed.

  Also, if it is determined in step S42 that PS2 is not accommodated and connected to home BS 3A, CPE 14 determines that it is accommodated and connected to roaming BS 3B, and calls to PS 2 through this roaming BS 3B with a normal call. The operation is started (step S50).

  The CPE 14 determines whether or not there is a response from the PS2 through the roaming BS 3B (step S51). If there is no response from PS2, this processing operation is terminated.

  If there is a response from PS2 in step S51, CPE 14 determines whether or not BS name 26 of this roaming BS 3B is in memory 13 (step S52).

  When the CPE 14 determines that the BS name 26 of the roaming BS 3B is in the memory 13, the CPE 14 reads the BS name 26 from the memory 13 (step S53), and displays the BS name 26 on the display unit of the MFT 5 (step S53). ), This processing operation ends. Note that the user of the MFT 5 can recognize the current position of the PS 2 based on the BS name 26 being displayed even if the call partner PS 2 is accommodated and connected to the roaming BS 3B.

  If it is determined in step S53 that the BS name 26 of the roaming BS 3B is not in the memory 13, the CPE 14 displays the out-of-service area on the display unit of the MFT 5 (step S55), and ends this processing operation. Note that the user of the MFT 5 can recognize that the current position of the PS 2 that is the call partner is out of the service area by displaying the out-of-service area being displayed.

  According to the call PS position search display process shown in FIG. 6, when the MFT 5 makes a call with the PS 2, the BS name 26 of the BS 3 corresponding to the PS 2 is displayed on the display unit of the MFT 5, so that the PS 2 is the home BS 3A or Even if it is accommodated and connected to the roaming BS 3B, the user of the MFT 5 can recognize the current position of the PS 2 that is the call partner.

  According to the present embodiment, when the location search special number and the PS number are detected from the MFT 5, it is determined whether or not the PS2 corresponding to the PS number is accommodated and connected to the roaming BS 3B, and this PS2 is accommodated and connected to the roaming BS 3B. If it is determined that the BS name 26 corresponding to the roaming BS 3B is displayed on the display unit of the MFT 5, the user of the MFT 5 specifies the PS 2 as a position search target by a simple operation. Even if the specified PS2 is accommodated and connected to the roaming BS 3B, the BS name 26 of the roaming BS 3B can be displayed, so that the current position of the PS 2 can be recognized by the BS name 26.

  According to the present embodiment, when the location search special number related to the silent incoming call is detected from the MFT 5, the home BS 3A or the roaming BS 3B that accommodates and connects the PS 2 is detected by the silent incoming call to the PS 2, and the silent incoming call is supported. Since the incoming call history is not left in PS2, the user of MFT5 can recognize the current position of PS2 without being noticed by the user of PS2.

  In the above embodiment, the BS 3 is arranged for each department in the company facility. However, for example, the BS 3 is arranged for each room in the facility, such as a construction site or a hospital. Also good.

  Further, in the above embodiment, when PS2 is accommodated and connected to roaming BS 3B during the PS position search display process, if the BS name 26 of this roaming BS 3B is not in the memory 13, the display section of MFT 5 is out of range. Although displayed, if the BS accommodation position 25 of the roaming BS 3B is stored in the memory, the BS accommodation position 25 may be displayed.

When the present invention detects a location search special number from a terminal with a display function and detects a mobile terminal number from this terminal with a display function, whether the mobile terminal corresponding to this mobile terminal number is accommodated and connected to the roaming base station When it is determined whether or not this mobile terminal is accommodated and connected to the roaming base station, the identification information corresponding to this roaming base station is displayed on the display unit of the terminal with a display function. A user of a terminal with a display function specifies a mobile terminal that is a location search target by a simple operation, and displays the identification information of the roaming base station even if the specified mobile terminal is accommodated and connected to the roaming base station. Thus, since this roaming base station can be recognized as the current location of the mobile terminal, for example, the mobile terminal and a host A beam base station or a roaming base station, and a private branch exchange accommodating connecting the home base station, in particular a private branch exchange in the housing connected to the display function switch from the terminal can recognize the position of the mobile terminal or the like Is preferred.

It is a block diagram which shows schematic structure inside the local radio | wireless communications system which shows embodiment of this invention. It is a block diagram which shows schematic structure inside CPE in connection with the local radio | wireless communications system which shows this Embodiment. It is explanatory drawing which shows the memory content of the memory in connection with this Embodiment. It is explanatory drawing which shows the display content of the display part of MFT in connection with this Embodiment. It is a flowchart which shows the processing operation of CPE in connection with PS position search display processing of this Embodiment. It is a flowchart which shows the processing operation of CPE regarding the call PS position display process of this Embodiment.

Explanation of symbols

1 Private wireless communication system 1A Private branch exchange (home station PBX)
2 Mobile terminal (PS)
3A Home Base Station (Home BS)
3B roaming base station (visitor base station / roaming BS)
5 Multi-function telephone (MFT: Terminal with display function)
6 Extension trunk (LIN)
13 Memory (memory means)
14 Central control unit (CPE)
31 Special number detection part (Special number detection means)
32 PS number detection unit (mobile terminal number detection means)
33 Roaming determination unit (roaming determination means)
34 Display control unit (display control means)

Claims (2)

And a base station for radio connection between the mobile terminals, a switch that accommodates a display function terminal,
The mobile terminal number of the mobile terminal and the accommodated BS number for identifying the base station that is accommodatingly connecting the mobile terminal or the roaming base station other than the base station are stored in association with each other, and the base station or the base station At least one of the BS number for identifying a roaming base station other than the BS, the BS accommodating position of the roaming base station other than the base station or the base station, or the BS name of the roaming base station other than the base station or the base station. Storage means for associating and storing
When receiving the mobile terminal number of the mobile terminal subject to location search and the location search special number for normal incoming call or the location search special number for ringing incoming call from the terminal with display function, the mobile terminal number associated with the received mobile terminal number is received. Specifying the accommodated BS number and performing a call operation by a normal incoming call or a ringing incoming call according to the received location search special number via the base station or the roaming base station corresponding to the identified accommodated BS number A control unit that executes the mobile terminal to be searched;
When there is a response to the call operation from the location search target mobile terminal, and a BS name is stored in the storage means in association with a BS number corresponding to the specified accommodated BS number A BS name corresponding to the specified accommodated BS number is displayed on the display unit of the terminal with display function , and there is a response to the call operation from the mobile terminal of the location search target. When the BS name is not stored in the storage means in association with the BS number corresponding to the accommodated BS number, and the BS accommodation position is associated with the BS number corresponding to the identified accommodated BS number. Display control means for displaying the BS accommodation position corresponding to the identified accommodation BS number on the display unit of the terminal with display function ;
An exchange equipped with. When the control unit receives a location search special number for a normal call from the terminal with a display function, the control unit executes the call operation so that an incoming call history remains in the mobile terminal for the location search, and has the display function when receiving the location inquiry access code non-ringing for incoming from the terminal, the exchanger according to claim 1 that perform the call operation so as incoming call history in the position searched for the mobile terminal does not remain.