JP2003134553A - Position searching phs terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position searching PHS terminal 15 that can sequentially confirm the position of the terminal in a state close to real time without decreasing a call time interval to a center station. SOLUTION: The center station and the position searching PHS terminal 15 transmit data with each other via a base station, the position searching PHS terminal 15 acquires the position information of a base station close to the position searching PHS terminal 15 at a prescribed time interval, transmits the information to the center station, and the center station is provided with a position searching function to search for the position of the position searching PHS terminal 15 on the basis of the received position information in a mobile communication system, the position searching PHS terminal 15 acquires the position information at an interval shorter than a prescribed time interval, stores the information to a RAM 4, and the position searching PHS terminal 15 reads the position information from the RAM 4 and transmits the information to the center station at the transmission of the position information at the prescribed time interval.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a PHS for position search.
Terminals, in particular, a mobile communication system that performs time-division data transmission between a center station and a PHS terminal for position search via a base station, and an existing transmission by the PHS terminal for position search The present invention relates to a position-finding PHS terminal device capable of searching an existing position of the position-finding PHS terminal device in a center station based on position information.

[0002]

2. Description of the Related Art Recently, as one of mobile communication systems, PHS (Personal Handy-phone) is used.
e System) has become widespread and is being used along with mobile phones. The PHS is designed as an extension of a cordless phone and is called a digital simple mobile phone system. It has a PHS terminal device that generates low output radio waves and a base station that transmits and receives radio waves between the PHS terminal device and the PHS terminal device. A mobile communication system is configured by a public communication line that is connected to a large number of base stations and performs data transmission between these base stations. In this case, the base station is provided at each place so as to cover the range within which the radio waves transmitted from the PHS terminal device reach, thereby setting the communicable range by the PHS terminal device.

By the way, in such a mobile communication system, in addition to the call function using the PHS terminal device, the center station is connected to the public communication line so that the existing position of the PHS terminal device for position search can be determined. Has a position search function for searching. A mobile communication system having this position search function is used for a position search PHS to be searched.
When transmitting or receiving a high frequency radio signal between the terminal device and the center station on a regular basis or according to one of the requests, the position searching PHS terminal device transmits the position searching PHS terminal device to the center station. The existing position information indicating the existing position is transmitted, and the position registration information obtained by processing the existing position information received by the center station is acquired or registered. Then, the center station can track the movement locus of the existing position of the PHS terminal for position search by acquiring and registering the position registration information. Further, by acquiring the position registration information, the center station can search for position search. It is possible to confirm the existing position of the PHS terminal.

Here, FIG. 3 is a schematic diagram showing an example of a main part configuration of a known mobile communication system having a position searching function.

As shown in FIG. 3, this mobile communication system
The stem is a position-finding PHS terminal device (P
S) 31 and the PHS terminal 31 for position search
Multiple base stations, four base stations (C
S) 32₁, 32₂, 32₃, 32_FourAnd each base station 32
₁, 32₂, 32₃, 32_FourA digital camera that connects the
Network (ISDN; Integrated Service)
Public communication such as es Digital Network)
The line (ISDN) 33 and the network connected to the integrated digital network.
Center station (CT) 34. In this case,
The center station 34 includes a control unit, a display unit, a storage unit, an input unit, etc.
Equipped information terminal device 34₁Is equipped with. Also,
Search PHS terminal 31 and each base station 32₁, 32₂, 32
₃, 32 _FourAre high-frequency transmitting and receiving antennas (see Fig. 3
PHS terminal device 31 for location search
And each base station 32₁, 32₂, 32₃, 32_FourBetween
Transmit and receive high frequency radio signals in a time division manner.

The mobile communication system having the above structure operates as follows.

First, the operation for calling the position searching PHS terminal 31 to be searched from the center station 34 and acquiring and registering the position registration information representing the existing position of the position searching PHS terminal 31 will be described.

A PHS terminal 3 for position search which is a search target
1 is a fixed time designated by the center station 34
PHS end for location search at the time of calling
A plurality of base stations 32 arranged close to the terminal 31₁Three
Two₂, 32₃, 32_FourHigh-frequency radio communication in time division between
Send and receive the No. The PHS terminal 31 for position search is
A plurality of base stations 32 when transmitting and receiving high frequency radio signals₁Three
Two₂, 32₃, 32_FourHigh-frequency radio signal transmitted by each
Signal is received and the reception level at that time is individually detected and acquired.
It The PHS terminal 31 for position search uses the received reception level.
Base station 32 corresponding to₁, 32₂, 32₃, 32_FourWhen
When transmitting / receiving, the corresponding base station 32₁, 32 ₂, 32
₃, 32_FourID and its reception level as the current location information
To send. Each base station 32₁, 32₂, 32₃, 32_Four
Receives the current position information from the PHS terminal device 31 for position search.
Then, the existing position information is sent through the public communication line 33.
It transmits to the center station 34. The center station 34 is at each base
Station 32₁, 32₂, 32₃, 32 _FourPosition supplied by
When the current location information of the search PHS terminal device 31 is received,
Predetermined information processing is performed on the existing position information, and
PH for position search which is a search target using the result of information processing
The S terminal device 31 indexes the existing location area and indexes it.
Acquire the existing location area as location registration information
Register the registered location information in the storage unit (database)
It

In this case, the center station 34 uses the position registration information registered in the storage section (database),
The movement locus of the existing position of the PHS terminal 31 for position search can be tracked and confirmed, and if the position registration information acquired immediately before is used, the existing position of the PHS terminal 31 for position search can be immediately confirmed. can do.

Next, the PHS terminal 31 for position search, which is the search target, makes an emergency call to the center station 34, and the center station 3
The operation when the position acquisition information indicating the existing position of the PHS terminal device 31 for position search is acquired by the terminal 4 will be described.

The PHS terminal 31 for position search is usually provided with an emergency call switch (not shown in FIG. 3),
When the emergency call switch is operated, even if there is no call from the center station 34, the position search PHS is performed.
A plurality of base stations 32 ₁ , which are arranged close to the terminal device 31,
High frequency radio signals are transmitted and received between 32 ₂ , 32 ₃ and 32 ₄ . At the time of transmitting / receiving the high frequency radio signal, the high frequency radio signals transmitted by the plurality of base stations 32 ₁ , 32 ₂ , 32 ₃ , 32 ₄ are respectively received, and the reception levels at that time are individually detected and acquired. The position-finding PHS terminal 31 has the base stations 32 ₁ , 32 ₂ , 3 corresponding to the acquired reception level.
When transmitting / receiving to / from 2 ₃ , 32 ₄ , the corresponding base station 32 ₁ ,
The IDs of 32 ₂ , 32 ₃ and 32 ₄ and their reception levels are transmitted as the existing position information. Base stations 32 ₁ , 32 ₂ , 3
Upon receiving the existing position information from the PHS terminal 31 for position search, 2 ₃ and 32 ₄ transmit the existing position information to the center station 34 through the public communication line 33. Center station 3
4 receives the existing position information of the PHS terminal 31 for position search supplied from each base station 32 ₁ , 32 ₂ , 32 ₃ , 32 ₄ , performs predetermined information processing on the existing position information, Using the result of the information processing, the location-searching PHS terminal 31 to be searched determines the existing location area and acquires the determined existing location area as location registration information. The center station 34 can immediately confirm the existing position of the PHS terminal 31 for position search that has made an emergency call by using the acquired position registration information. Note that the center station 34 immediately disconnects the line connection with the PHS terminal 31 for position search when acquiring the position registration information.

Next, when the center station 34 calls the position-finding PHS terminal device 31 to be searched at a fixed time interval, the position-finding PHS terminal device 31 is moved by the center station 34.
This section describes the callback function that allows you to set the calling time interval of.

When receiving the call back setting information from the center station 34, the location searching PHS terminal 31 sets the calling time interval of the center station 34 on the side of the location searching PHS terminal 31 within the range of 1 to 32767 seconds. The time can be set to any time interval, and the center station 34 thereafter calls the PHS terminal device 31 for position search at time intervals according to the set time interval. When the call back function is set, the center station 34 only acquires the location registration information obtained by processing the existing location information transmitted from the location searching PHS terminal 31 to the center station 34, and then performs the location registration. Information is not registered. Therefore, the center station 34 can confirm the existing position of the PHS terminal device 31 for position search, but cannot confirm the tracking of the movement locus of the existing position of the PHS terminal device 31 for position search.

[0014]

In the known mobile communication system, when the center station 34 calls the position-finding PHS terminal 31 to be searched at a fixed time interval, the center station 34 PH for position search at each time when the PHS terminal 31 for position search is called
Although it is possible to intermittently confirm the existing position of the S terminal device 31 and to know the movement trajectory of the existing position of the position searching PHS terminal device 31 in a fragmentary manner, the existing position of the position searching PHS terminal device 31 can be determined. It cannot be confirmed sequentially in real time.

Further, the known mobile communication system is
When the position-finding PHS terminal device 31 to be searched makes an emergency call to the center station 34, the center station 34 causes the position-search PHS terminal device 31 to make an emergency call. However, the existing position of the PHS terminal 31 for position search cannot be sequentially confirmed in real time.

Further, in the known mobile communication system, if the center station 34 is set to greatly shorten the time interval for calling the position-finding PHS terminal 31 to be searched by using the callback function, PHS for location search
Although the existing position of the terminal device 31 can be sequentially confirmed in a near real-time state, if the time interval for calling the position searching PHS terminal device 31 is set to be significantly shortened, the center station 34 and the position searching PHS terminal are set. Bowl 31
Since the line connection is frequently made between the location and, the power consumption of the power supply battery of the PHS terminal device 31 for position search greatly increases,
Not only the replacement cycle of the power supply battery becomes faster and the maintenance cost including the power supply battery increases, but also the public communication line 3
Since the exclusive time of the PHS terminal 31 for position search in No. 3 is significantly increased, it becomes necessary to improve the traffic of the public communication line 33.

The present invention has been made in view of such a technical background, and an object thereof is to provide an existing PHS terminal for position search which is a search target without shortening a time interval for calling from a center station. It is an object of the present invention to provide a PHS terminal device for position search capable of sequentially confirming a position in near real time.

[0018]

In order to achieve the above object, according to the present invention, data transmission is performed in a time division manner between a center station and a PHS terminal for position search via a base station.
The position-finding PHS terminal device acquires the existing position information of the base stations arranged close to the position-finding PHS terminal device at regular time intervals according to a command from the center station, and transmits the acquired existing position information to the center station. A PHS terminal for position search used for a mobile communication system having a position search function for searching the existing position of a PHS terminal for position search based on existing position information received by a center station, The PHS terminal voluntarily acquires the existing position information at intervals shorter than the fixed time interval and stores it in the built-in memory, and when transmitting the existing position information at the fixed time interval, the existing position information stored in the built-in memory is stored. And a means for reading out and transmitting it to the center station.

According to the above-mentioned means, the position searching PHS terminal voluntarily acquires the existing position information at an interval shorter than the fixed time interval for the center station to call the position searching PHS terminal, and the acquired existing position information is acquired. The location information is stored in the built-in memory. When the center station transmits the location information at a fixed time interval for calling the PHS terminal for location search, the location information stored in the built-in memory after the last location information was transmitted. Since the position information is read and the read existing position information is transmitted to the center station, the center station uses the existing position information acquired at intervals shorter than a certain time interval to detect the position searching PHS terminal device. The movement locus of the existing position can be tracked, and the existing position of the PHS terminal for position search can be sequentially confirmed in near real time. In addition, even if the existing position information is acquired at an interval shorter than a fixed time interval, transmission / reception (communication) is not performed with the center station when the existing position information is acquired. It is possible to reduce the consumption of the power source battery and to improve the traffic of the public communication line separately.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows one embodiment of a PHS terminal device for position search according to the present invention, and is a block diagram showing the configuration of the main part thereof.

As shown in FIG. 1, the PHS terminal 15 for position search according to the present embodiment has a control unit (CPU) 1 for integrally controlling each component, a high frequency signal transmission process and a high frequency signal reception. High-frequency signal transceiver 2 for processing
A clock signal oscillator 3 for generating a base clock signal for the control unit 1, and a RAM 4 for storing various data.
And a ROM 5 storing an operation program of the control unit 1,
Communication status display light emitting element (communication status display LED) 6 for displaying communication status by a light emitting element (LED), and program ROM storing registration data such as subscriber data
(PROM) 7, reset integrated circuit (reset IC) 8 for generating an internal reset signal of control unit 1, emergency call switch 9 for generating an emergency call by operation, and external equipment (not shown in FIG. 1) I / that inputs and outputs data to and from
O terminal 10, power supply battery (BAT) 11, power supply battery 1
Power switch 12 for turning on and off 1 and power battery 1
A voltage regulator (REG) 13 for adjusting the output voltage of 1;
A high frequency antenna 14 for transmitting and receiving high frequency radio signals.

The control unit 1 includes a high frequency signal transmission / reception unit 2, a clock signal oscillator 3, a RAM 4, a ROM 5, a communication status display light emitting element 6, a program ROM 7, a reset integrated circuit 8, an emergency call switch 9 and an I / O terminal. 10 and the voltage regulator 12, respectively. The power supply battery 11 includes a high frequency signal transmitter / receiver 2, a clock signal oscillator 3, a reset integrated circuit 8, and a voltage regulator 1 via a power switch 12.
3 are connected respectively.

2 (a) and 2 (b) are external views of the main body case accommodating the PHS terminal 15 for position search shown in FIG. 1, and FIG. b) is a side view thereof.

2 (a) and 2 (b), 16 is a main body case, 16 ₁ is a cover of the battery housing portion of the power supply battery 11 housed in the main body case 16, and other components shown in FIG. The same components as those of the elements are designated by the same reference numerals.

As shown in FIG. 2 (a), the main body case 16 has a flat shape in which the front surface is substantially square, and the constituent parts including the control unit 1 are housed in the left half portion when viewed from the front. A battery compartment for accommodating the power supply battery 11 is arranged in the right half when viewed from the front. A cover 16 _{1 which} is openable and closable with one end as a fulcrum is provided on the upper part of the battery housing, and the power battery 11 is detachably housed inside the battery housing. On the upper left side of the main body case 16, a PH for position search
A light emitting element (L
ED), for example, a communication status display light emitting element 6 that emits blue, red, and orange, and an emergency call switch 9 that makes an emergency call are provided. The high frequency antenna 14 is arranged so as to extend above the body case 16.

As shown in FIG. 2B, the body case 16 has a slide type power switch 1 on the left side surface.
2 are arranged.

By the way, the position searching PHS terminal 15
R program subscriber data prior to use
It is necessary to write in the OM7 and register the subscriber data. The writing of the subscriber data is performed by a predetermined operation member such as the emergency call switch 7 and the power switch 12.
This is performed by performing a predetermined operation as described below. The predetermined operation in this case is as follows, for example.

First, the power switch 12 is turned on to supply a power supply voltage to each component of the position-finding PHS terminal 15.

Next, after turning on the power switch 12,
The emergency call switch 7 is operated twice within 3 seconds. At this time, if the emergency call switch 7 is not operated within 3 seconds or more after the power switch 12 is turned on, even if the emergency call switch 7 is operated, the operation is performed twice. If not, the normal operating state is entered.

Next, when the emergency call switch 7 is operated twice, the blue light emitting element in the communication status display light emitting element 6 blinks for about 2 seconds. Therefore, the emergency call switch 7 is operated three times during this blinking period. To do. At this time, if the emergency call switch 7 is not operated during the blinking period of the blue light emitting element, or if the emergency call switch 7 is not operated three times even if the emergency call switch 7 is operated, the normal operation state is set. become.

Subsequently, when the emergency call switch 7 is operated three times, the blue light emitting element in the communication state display light emitting element 6 lights for about 2 seconds, and the subscriber data registration state is entered. At this time, the subscriber data is imported from the data writer (not shown in FIG. 1) to the position searching PHS terminal 15 through the I / O terminal 10 or the high frequency antenna 14, and the registered registration of the imported subscriber data is performed. During the subscriber data write / registration operation, the orange light emitting element in the communication status display light emitting element 6 blinks.

Next, when the subscriber data write registration is completed, the orange light emitting element is turned off. At this time, when the subscriber registration of the subscriber data is not properly performed, the red light emitting element in the communication status display light emitting element 6 blinks.

After this, when the subscriber data write registration is completed, the power switch 12 is once turned off. Then, when the power switch 12 is turned on, the PHS terminal 15 for position search comes to have a position registration function based on the registered subscriber data.

If the subscriber data is not properly registered for writing, the power switch 12 may be turned off once, and the subscriber data may be registered again for writing in accordance with the operation procedure.

The operating members and operating procedures used when such subscriber data write-in registration is not limited to the operating members and operating procedures described above,
It is possible to change the operation member and the operation procedure.

Here, referring to FIGS. 1 and 2A and 2B, the PHS terminal 1 for position search according to this embodiment.
The operation of No. 5 will be described.

The PHS terminal 15 for position search is provided with the control unit 1.
When called by the center station (not shown) at fixed time intervals, the position searching PH is transmitted through the high frequency signal transmitting / receiving unit 2 at the time of calling.
Not shown in the drawing, which is arranged close to the S terminal 15
High frequency radio signals are transmitted and received to and from one or a plurality of base stations in a time division manner. When the high-frequency signal transmitting / receiving unit 2 receives the high-frequency wireless signals transmitted by one or more base stations during transmission / reception of the high-frequency wireless signals, the control unit 1 individually detects and acquires the reception levels of those high-frequency wireless signals. The existing position information including the acquired reception level and the ID of the base station corresponding to the reception level is formed, and the formed existing position information is stored in the RAM 4.

Further, the position searching PHS terminal device 15 is controlled by the control unit 1 before the fixed time interval designated by the center station arrives, that is, from the time when the last time interval arrives to the next time interval. During the arrival time of 1), it is time-divided with one or a plurality of base stations (not shown) which are arranged in proximity to the position-finding PHS terminal 15 once or a plurality of times through the high-frequency signal transmitting / receiving unit 2. It transmits and receives high frequency wireless signals. Also at this time, the high-frequency signal transmitting / receiving unit 2 does not perform 1
When receiving the high frequency radio signals transmitted by one or a plurality of base stations, the control unit 1 individually detects and acquires the reception levels of those high frequency radio signals, and acquires the obtained reception levels and the base stations corresponding to the reception levels. The existing position information including the ID is formed, and the formed existing position information is stored in the RAM 4.

Then, the PHS terminal 15 for position search is
When a certain time interval designated by the center station arrives under the control of the control unit 1, the position finding PHS terminal device 15 and the center station are communicated with each other through the high-frequency signal transmitting / receiving unit 2, the base station, and a public communication line (not shown). Connect the line. At the time of this line connection, the control unit 1 reads out a plurality of existing position information stored in the RAM 4 which are respectively formed between the arrival time of the previous time interval and the arrival time of the current time interval, and read out a plurality of read out position information. The existing position information is transmitted to the center station through the high frequency signal transmitter / receiver 2, the base station and a public communication line (not shown).

The center station is the PHS terminal 1 for position search.
When receiving the plurality of existing position information supplied from 5, the predetermined information processing is performed on each of the plurality of existing position information, and the position search PHS terminal device 15 currently exists using the result of the information processing. Position area indexing,
The position areas of the PHS terminal 15 for position search that have changed between the arrival time of the previous time interval and the arrival time of the current time interval are indexed, and the indexed position areas are acquired as position registration information and acquired. The registered position registration information is registered in the storage unit (database).

In this case, the center station uses the position registration information registered in the storage unit (database), for example, the position registration information acquired at the latest point in time, to detect the position searching PHS terminal device 15. The existing position can be confirmed immediately, and by using the position registration information acquired at a plurality of time points dating from the latest time point, the movement trajectory of the position transition of the PHS terminal 15 for position search can be tracked and confirmed. Is something that can be done.

Further, the position searching P according to this embodiment is also used.
Also in the HS terminal device 15, when the emergency call switch 9 is operated, even if there is no call from the center station under the control of the control unit 1, the position searching PHS terminal device 15 through the high frequency signal transmitting / receiving unit 2 High frequency radio signals are transmitted and received to and from one or a plurality of base stations arranged close to each other. When the high-frequency signal transmitting / receiving unit 2 receives the high-frequency wireless signals transmitted by one or a plurality of base stations during the transmission / reception of the high-frequency wireless signals, the control unit 1 individually detects and acquires the reception levels of the high-frequency wireless signals. Then, the existing position information including the acquired reception level and the ID of the base station corresponding to the reception level is formed. At this time, the control unit 1 connects the position-finding PHS terminal 15 and the center station through the high-frequency signal transmission / reception unit 2, the base station, and the public communication line, and transmits the formed existing position information and emergency information to the center station. Send. When the center station receives the supplied current position information of the position-finding PHS terminal device 15, the center station performs predetermined information processing on the existing position information and uses the result of the information processing to perform the position-finding PHS terminal device. 15 determines the existing position area, and acquires the calculated existing position area as position registration information.

By using the acquired position registration information, the center station can immediately confirm the existing position of the PHS terminal 15 for position search which has made an emergency call. In addition,
Upon acquiring the location registration information, the center station immediately disconnects the line connection with the location-finding PHS terminal 15.

Further, in the position-finding PHS terminal device 15 according to this embodiment, when the center station calls the position-finding PHS terminal device 15 at regular time intervals, the call time interval can be arbitrarily set. It has a back function, and the PHS terminal 15 for position search
When receiving the call back setting information from the center station, the location searching PHS terminal 15 side can set the calling time interval of the center station to any time interval within the range of 1 to 32767 seconds. When the calling time interval is set, the center station subsequently calls the position searching PHS terminal 15 at a time interval according to the set time interval. When this callback function is set, the center station
Only the location registration information obtained by processing the existing location information transmitted from the terminal 15 to the center station is acquired, but the location registration information is not registered. Therefore, the center station can confirm the existing position of the PHS terminal device 15 for position searching, but cannot confirm the tracking of the movement locus of the existing position of the PHS terminal device 15 for position searching.

As described above, according to the position searching PHS terminal device 15 of this embodiment, in the center station,
Since the movement locus of the existing position of the PHS terminal 15 for position search can be tracked by using the existing position information acquired at intervals shorter than the fixed time interval, the PH for position search is used.
The existing position of the S terminal device 15 can be sequentially confirmed in near real time.

Further, the position searching P according to this embodiment is used.
According to the HS terminal device 15, even if the existing position information is acquired at an interval shorter than a fixed time interval, transmission / reception with the center station is not performed when the existing position information is acquired. It is possible to reduce the consumption of the power supply battery 11 of the PHS terminal device 15 and to separately improve the traffic of the public communication line.

[0048]

As described above, according to the present invention, the location searching PHS terminal voluntarily voluntarily uses the existing location information at intervals shorter than a certain time interval for the center station to call the location searching PHS terminal. And the acquired existing position information is stored in the built-in memory. When the center station transmits the existing position information at a fixed time interval for calling the PHS terminal for position search, the existing position information was transmitted last time. Since the existing position information stored in the internal memory later is read and the read existing position information is transmitted to the center station, the center station uses the existing position information acquired at intervals shorter than a certain time interval, It is possible to track the movement locus of the existing position of the PHS terminal for position searching, and to sequentially confirm the existing position of the PHS terminal for position searching in a near real-time state. Not only is this possible, but even if the existing position information is acquired at intervals shorter than a fixed time interval, transmission / reception (communication) is not performed with the center station when the existing position information is acquired. It is possible to reduce the consumption of the power supply battery of the terminal device and to improve the traffic of the public communication line separately.

[Brief description of drawings]

FIG. 1 is a block diagram showing one embodiment of a PHS terminal device for position search according to the present invention and showing a main configuration thereof.

2A and 2B are a front view and a side view showing the appearance of the PHS terminal for position search shown in FIG.

FIG. 3 is a schematic diagram showing an example of a main configuration of a mobile communication system having a known position searching function.

[Explanation of symbols]

1 Controller (CPU) 2 High Frequency Signal Transmitter / Receiver 3 Clock Signal Oscillator 4 RAM 5 ROM 6 Communication Status Display Light Emitting Element (Communication Status Display LED) 7 Program ROM (PROM) 8 Reset Integrated Circuit (Reset IC) 9 Emergency Call Switch 10 I / O Terminal 11 Power Battery (BAT) 12 Power Switch 13 Voltage Regulator (REG) 14 High Frequency Antenna 15 PHS Terminal for Position Search 16 Body Case 16 ₁ Cover

Claims (2)

[Claims] 1. Data transmission is performed in a time division manner between a center station and a PHS terminal for position search via a base station,
The position-finding PHS terminal device obtains the existing position information of the base stations arranged in proximity to the position-finding PHS terminal device at regular time intervals according to a command from the center station, and the obtained existing position information is used by the center. A PHS terminal for position search used in a mobile communication system having a position search function for transmitting the current position of the PHS terminal for position search based on the existing position information received by the center station. Therefore, the position-finding PHS terminal voluntarily acquires the existing position information at intervals shorter than the fixed time interval and stores it in the built-in memory, and when transmitting the existing position information at the fixed time interval. A PHS terminal device for position search, which reads out the existing position information stored in the built-in memory and transmits it to the center station. 2. The position-finding PHS terminal according to claim 1, wherein the existing location information includes a base station ID and electric field strength information of a received radio wave.