JPH08289358A - Method and device for estimating position of cordless telephone set in cordless telephone system - Google Patents

Abstract

PURPOSE: To simplify the constitution of a station B and to quickly estimate the position by making each base station transmit a signal S including its own station discrimination code C and estimating the nearest station B in a mobile station M in accordance with reception levels and codes C of signals S from stations B. CONSTITUTION: A private branch exchange 1 receives signals S including base station discrimination codes C transmitted from cordless telephone sets 3A to 3C through base stations 2A to 2D and outputs them to a computer 4. The computer 4 uses codes C and levels of signals S to estimate the nearest base stations to telephone sets of transmission sources of signals S and displays them on a display device 5 which has a map to indicate respective base stations. Stations 2A to 2D are connected to the private branch exchange 1 by wires and transmit the radio signals including respective peculiar discrimination codes to telephone sets 3A to 3C, and telephone sets 3A to 3C are connected to one of stations 2A to 2D by radio to perform transmission and reception. Thus, the constitution of the base station is simplified, and the position is quickly estimated.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cordless telephone system, and more particularly to an estimation device and an estimation method for estimating a base station closest to the location of a cordless telephone.

[0001]

2. Description of the Related Art Conventionally, in this type of cordless telephone system, a plurality of base stations are installed in a distributed manner, and the cordless telephone performs location registration by radio signals to any of these base stations. When the cordless telephone moves and the reception level of the radio wave from the base station with which the cordless telephone is communicating becomes low, the cordless telephone cannot normally communicate with the base station, and thus the radio waves of other base stations are searched. When a base station with a reception level above a certain level is detected from the radio waves of the searched base stations,
The cordless telephone registers its location with the base station.

On the other hand, in a factory cordless telephone system, a manager calls a cordless telephone,
Alternatively, the position of the cordless telephone is detected to perform other management. The management side estimates that the cordless telephone exists near the base station by detecting the base station in which the cordless telephone is registered.

However, under normal base station installation conditions, the wireless zones of the individual base stations are set so as to overlap each other in order to eliminate the dead zone where calls can be made and received. The location of the cordless telephone may not always be the closest to the base station with which the cordless telephone is registered, which causes a problem that the estimation error of the position of the cordless telephone becomes large.

In order to solve such a problem, conventionally, the base station side detects the reception level of each cordless telephone,
A method of registering the location is used. For example, in the technique described in Japanese Patent Application Laid-Open No. 2-393738 (Reference 1), a plurality of fixed devices (base stations) detect a reception level of a signal from a wireless telephone (cordless telephone), and Notify wireless phone. The wireless telephone selects the nearest fixed device based on these reception levels and performs location registration.

By adopting this kind of configuration, in the technique described in Document 1, the location of the wireless telephone is registered based on the reception level between the wireless telephone and a plurality of fixed devices, so that the wireless telephone is located near the nearest location. The probability of location registration for a fixed device is high. Therefore, by detecting the base station in which the position of the wireless telephone is registered on the management side, the existence position of the wireless telephone can be known to some extent accurately.

As a related technique, among the radio waves from each base station, the electric field strengths of the radio waves of three base stations are measured in descending order of the electric field strength, and the ID codes of the three base stations are measured from the measured radio waves. Mobile phone for detection is Japanese Patent Laid-Open No. 5-297.
No. 107 (reference 2). In Reference 2, the mobile phone calculates the distance to each base station from the measured electric field strength, and determines the current position of the mobile phone from the calculated distance.

[0007]

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention
In the described technique, each fixed device needs to be provided with a reception level detection unit in order to detect the reception level of the wireless telephone, which causes a problem that the structure of the fixed device is complicated. .

Further, in the technique described in Document 2, the mobile phone detects the reception levels of a plurality of base stations to determine the current position, but the management side or the cordless phone side can estimate the nearest base station. There is a problem that the base station cannot detect the current position of the mobile phone.

An object of the present invention is to solve the above problems and provide a position estimating device and an estimating method for a cordless telephone in a cordless telephone system which can estimate the nearest base station only on the cordless telephone side.

Another object of the present invention is to provide a position estimating device and an estimating method for a cordless telephone in a cordless telephone system capable of estimating the nearest base station of a portable telephone by management.

[0011]

In order to achieve the above-mentioned object, the present invention provides an exchange, a plurality of base stations connected to the exchange, and wireless communication with these base stations. A cordless telephone system configured to perform at least one cordless telephone, wherein each of the plurality of base stations has means for transmitting a signal including a base station identification code indicating its own base station. The cordless telephone, the detection means for detecting a reception level of a signal including the base station identification code transmitted from each base station, a reception level of each reception signal detected by the detection means, and each reception Estimating means for estimating the nearest base station based on the base station identification code included in the signal.

Further, the present invention is a cordless telephone system comprising an exchange station, a plurality of base stations connected to the exchange station, and at least one cordless telephone that wirelessly communicates with these base stations. A method for estimating the position of a cordless telephone in, wherein each base station transmits a signal including a base station identification code indicating its own base station, and the cordless telephone identifies the base station transmitted from each base station. A step of receiving a signal containing a code, a reception level of each reception signal in the cordless telephone,
Estimating the nearest base station based on the base station identification code included in each received signal.

By adopting the above configuration, in the present invention, the cordless telephone creates a plurality of pair information in which each identification code is associated with the detected reception level based on the signal from each base station, and these pair information are created. Among them, the one having the highest reception level is selected, and the base station is estimated from the pair information corresponding to the selected reception level. Therefore, the nearest base station can be estimated.

[0014]

DETAILED DESCRIPTION OF THE INVENTION The present invention will now be described in detail with reference to the drawings.

In the present embodiment, an example in which the present invention is applied to a private cordless telephone system in which a plurality of base stations are connected to a private branch exchange of an exchange and each base station forms a wireless zone in which the base stations overlap each other is shown.

FIG. 1 is a system diagram of a cordless telephone system showing an embodiment of the present invention. In FIG.
The cordless telephone system includes a private branch exchange 1, a computer 4, a display device 5, base stations 2A to 2D, and cordless telephones 3A to 3C.

The private branch exchange 1 is connected to a computer 4, and the computer 4 is connected to a display device 5. The private branch exchange 1 includes the cordless telephones 3A to 3C to the base station 2
The pair information including the base station identification signal and the reception level signal transmitted via A to 2D is received, and the pair information is output to the computer 4.

Using the pair information, the computer 4 estimates the base station closest to the cordless telephone that has transmitted the pair information. The display device 5 has a map showing each base station, and displays the presence of the cordless telephone which has transmitted the pair information in the column of the nearest base station estimated by the computer 4.

The plurality of base stations 2A to 2D are private branch exchanges 1.
Is connected to the cordless telephones 3A to 3C with a wireless signal including a unique identification code.

The cordless telephones 3A to 3C wirelessly connect to one of the plurality of base stations 2A to 2D to send and receive signals.

Next, the signal format of the signal transmitted from each base station and the signal format of the signal transmitted from each cordless telephone will be described.

FIG. 2A is a signal format diagram showing a signal transmitted from each base station.

In FIG. 2A, the signals transmitted from each base station are the channel identification signal 211 for identifying the channel of the transmission signal, the system identification signal 212 for identifying the cordless telephone system, and the signal. A base station identification signal 213 for identifying a base station to be transmitted, an information signal 214 containing information from the base station, and a redundant signal 215 corresponding to a redundant bit.

FIG. 2B is a signal format diagram showing a signal transmitted from each cordless telephone to the base station.

In FIG. 2B, the signal transmitted from each cordless telephone to the base station is a channel identification signal 221 for identifying the channel of the transmission signal and a system identification signal 22 for identifying the cordless telephone system.
2, a base station identification signal 223 for identifying the base station currently communicating, and a cordless telephone identification signal 22 for identifying the cordless telephone transmitting the signal.
4, an information signal 225 into which pair information created by the mobile station is inserted, and a redundant signal 215 corresponding to a redundant bit.

The information channel 225 has type information 227 indicating that it is a pair of pair information, and a base station identification signal 2
28 and a reception level signal 229 indicating the reception level of the signal transmitted by the base station.

Next, the internal functional configuration of the cordless telephone will be described.

FIG. 3 is a functional block diagram of the cordless telephone.

In FIG. 3, the cordless telephone has an antenna 20 for transmitting and receiving radio signals, a transmitting / receiving unit 11 connected to the antenna 20, a transmitter 12, and a baseband circuit unit 14 to which a receiver 13 is connected. A reception level detection unit 15 connected to the transmission / reception unit 11 for detecting the reception level of a reception signal, and a control unit for processing the detected reception level and controlling the respective units, and an operation key unit 16 and a display unit 17 are connected. It has a control circuit 18 and a memory circuit 19 such as a ROM or a RAM.

FIG. 4 is a functional block diagram showing the internal structure of the control circuit.

In FIG. 4, the control circuit 18 includes a pair information section 181, a comparing section 182, and a judging section 183.

Next, the operation of the control circuit 18 will be described.

The pair information unit 181 identifies, for each signal transmitted from each of the base stations 2A to 2D, the reception level detected by the reception level detection unit 15 and the signal included in the signal decoded by the baseband circuit 14. Pair information corresponding to the code is created. The created pair information is stored in the memory 19 by the pair information unit 181.

After the pair information is stored in the memory 19, the comparison unit 182 reads the pair information from the memory 19, compares the read reception levels with each other, selects the pair information having the largest reception level, and reads the pair information. Judgment unit 1 with pair information
Output to 83. The determination unit 183 estimates that the base station indicated by the identification code of the pair information selected by the comparison unit 182 is the nearest base station, and that the pair information input from the comparison unit 182 includes the identification number of its own cordless telephone. Is added and transmitted to the base stations 2A to 2D whose current position is registered via the transmission / reception unit 11. Further, the determination unit 183 outputs the pair information to the display unit 17 to display it.

The location registration with respect to the base station is performed according to a sequence that has been conventionally used in addition to this embodiment. The control circuit 18 is, for example, an NEC M
It can be configured with a general-purpose chip such as PU “V40HL”.

Next, the operation will be described with reference to the flowchart shown in FIG.

In the following description, it is assumed that the cordless telephone 3A is registered in the base station 2A.

Now, when the cordless telephone 3A moves from the vicinity of the base station 2A to the point X1 near the base station 2B, the radio wave from the base station 2A gradually weakens, but the base detected by the reception level detector 15 While the reception level of the station 2A is higher than a preset threshold value, the control circuit 1
8 does not update the location registration with other base stations, but the reception level is a preset threshold value, for example 80 dB.
When it becomes lower than μm, the control circuit 18 updates the position registration with another base station as shown below (start).

The cordless telephone 3A receives the signals from the base stations 2A to 2D at the transmission / reception unit 11 and detects the identification code thereof, and at the same time, detects the reception level at the reception level detection unit 15 and compares them. Part 181
Is input (S501). The pair information unit 182 creates a pair information signal by pairing the identification code and the reception level for each base station, and stores the pair information signal in the memory 19 (S50).
2).

When the input of the identification code and the reception level for each base station is completed (S503), the comparison unit 182 compares the reception levels of the pair information and detects the reception level with the highest reception level (S504). . For example, the base station 2A
Each reception level of ~ 2D is 80 dBm, 30 dBm,
With 20 dBμm and 10 dBμm, 80 dBμm is detected, and it is estimated that the cordless telephone is located closest to the base station 2A. In addition, each reception level of each base station is 30 dBμm, 80 dBμm, 20 dBμm, 10 dBm
Assuming dB μm, 80 dB μm is detected, and it is estimated that the cordless telephone is closest to the base station 2B and close to the base station 2A.

Subsequently, the comparison unit 182 detects the identification signal of the base station paired with the reception level having the highest reception level (S505), and the identification signal of the base station detected by the determination unit 183 in S505 is displayed on the display unit. It is determined whether or not it is displayed in 17 (S506).

If it is determined in S506 that the display is not displayed on the display unit 17, the display is performed (S507). If the display is displayed, the determination unit 183 receives the paired received identification signal. The identification signal of the currently registered base station is added to the pair information signal including the level (S508).
Further, the determination unit 183 adds its own identification signal to the signal created in S508 (S509) and outputs it to the baseband circuit 14 (S510).

The baseband circuit 14 creates the signal shown in FIG. 2B based on the signal from the control circuit 18, and registers the current position in the base station via the transmitting / receiving unit 11 and the antenna 20. The signal is transmitted to the base station being operated.

Next, the operation of the private branch exchange will be described with reference to FIG.

In FIG. 6, the private branch exchange 1 transmits the received paired information to the computer 4 (start), and the computer 4 receives them (S601). The computer 4 detects the identification signal of the cordless telephone from the received signal (S602) and stores the pair information signal corresponding to the detected identification signal of the cordless telephone (S603). The computer 4 determines whether the reception is completed (S60
4) If not completed, return to the processing of S601.
On the other hand, when the reception is completed, the computer 4
Detects the maximum value of the reception level corresponding to each of the identification signals of the plurality of cordless telephones (S605) and detects the identification signal of the base station corresponding to the detected reception level (S606). Estimate the nearest base station. For example, the pair information transmitted from the cordless telephone is (A (identification code indicating the base station 2A), 30d
B μm), (B (identification code indicating the base station 2B), 80d
B μm), (C (identification code indicating the base station 2C), 20d
B μm), (D (identification code indicating the base station 2D), 10d
B μm), the computer 4 is the pair information having the maximum reception level among the four pieces of pair information (B (base station 2
(Identification code indicating B), 80 dBμm) are selected. Then, it is estimated that the base station 2B indicated by the identification code B of the pair information is the base station closest to the cordless telephone.

Subsequently, the computer 4 has the display device 5
The presence of the cordless telephone is displayed in the column of the base station 2B on the map (S607, see the memory 19 in FIG. 4).

The display device 5 can display the positions of all cordless telephones 3A to 3C used in the system. Therefore, by using the display of the display device 5, it is possible to confirm the current positions of all cordless telephones in the premises and the position of the person who is using the cordless telephone.

Next, another embodiment will be described.

In another embodiment, it is assumed that only the pair information is created by the control circuit 18 of the cordless telephones 3A to 3C,
The function of estimating the nearest base station is performed by a personal computer that is set arbitrarily. Also, the nearest base station shall be made to perform the personal computer.

FIG. 7 is a system diagram of a cordless telephone system showing another embodiment.

In FIG. 7, the personal computer 5
Since the system configuration other than 0 is the same as that of the system of the first embodiment, the description of the elements having the same numbers is omitted.

The personal computer 50 is arranged at an arbitrary place or is carried by a person who uses a cordless telephone.

Next, the internal configurations of the cordless telephone and personal computer will be described.

FIG. 8 is a functional block diagram of a cordless telephone and a personal computer.

In FIG. 8, each cordless telephone 3A-
The 3C and the personal computer 50 are configured to be connectable by a connector (not shown).

Control circuit 1 of cordless telephones 3A to 3C
Reference numeral 8 has only the function of creating pair information in the first embodiment, and stores it in the created pair information memory 19.
Further, the cordless telephones 3A to 3C do not have the display unit 17 that displays the nearest base station.

Control circuit 6 of personal computer 50
0 indicates that when the cordless telephones 3A to 3C and the personal computer 50 are connected, the cordless telephones 3A to 3C.
The pair information is received from 3C and temporarily stored in the memory 61.
Then, the maximum reception level is selected from the stored pair information, the base station indicated by the identification code of the selected pair information is estimated as the nearest base station, and the base station is displayed on the display unit 62. In this way, the cordless telephone can be made simpler.

Next, the operation of the personal computer will be described with reference to the flowchart shown in FIG.

In FIG. 9, the control circuit 60 receives the pair information signal from the control circuit 18 (S901), and stores the pair information signal in the memory 61 (S902). Control circuit 6
0 detects the maximum value of the reception level from the pair information signal (S
903), the identification signal of the base station that is paired with the detected reception level with the maximum value is detected from the pair information signal (S904).
Then, the control circuit 60 causes the display unit 62 to display the base station brightness of the detected identification signal.

If the control circuit 18 of the cordless telephones 3A to 3C has a function of transmitting pair information to the private branch exchange 1 via the base station whose location is registered as in the first embodiment, The location management of the cordless telephone can be performed by the exchange 10 as in the above embodiment.

If the personal computer 50 is provided with a function of creating pair information of the reception level and the identification code received by the cordless telephone, the cordless telephone simply has the reception level detecting function and the identification code receiving function. It may be provided, and the configuration of the cordless telephone can be further simplified.

In the above embodiment, the present invention is applied to a private branch exchange, but the present invention can be applied to a cordless telephone system using a central office exchange.

[0063]

As described above, according to the present invention, it is not necessary to provide each base station with a structure for detecting the reception level of a signal from each cordless telephone, and the structure of each base station can be simplified. In addition, when estimating the position of the cordless telephone, it is not necessary to send and receive signals in a complicated sequence between the cordless telephone and the base station, and the position can be estimated quickly, and the cordless telephone can be located near the base station. Can be estimated.

Further, according to the present invention, a computer is connected to an exchange connected to each base station, and the position detection is performed by the computer based on the pair information created by the cordless telephone, thereby displaying a plurality of cordless telephones on the display device. It can be displayed in and can be managed arbitrarily. Even in this case, since the position estimation can be performed only by the signal received by the cordless telephone, the configuration of the base station is not complicated.

Furthermore, the present invention connects a cordless telephone to a personal computer provided at an arbitrary position,
If the position estimation and the position display are performed in the personal computer based on the pair information, the position can be displayed even if the cordless telephone is not provided with a control circuit or a display unit for detecting the position. Can be simplified. Even in this case, since the position can be estimated only by the signal received by the cordless telephone, the structure of the base station is not complicated.

[Brief description of drawings]

FIG. 1 is a system diagram of a cordless telephone system showing a first embodiment of the present invention.

2 is a signal format diagram showing a signal transmitted from each base station of FIG. 1 and a signal transmitted from a cordless telephone.

FIG. 3 is a functional block diagram of the cordless telephone of FIG.

FIG. 4 is a functional block diagram of the control circuit of FIG.

5 is a flowchart for explaining the operation of the control circuit of FIG.

6 is a flow chart for explaining the operation of the computer shown in FIG.

FIG. 7 is a system diagram of a cordless telephone system showing a second embodiment of the present invention.

8 is a functional block diagram of the cordless telephone and personal computer of FIG.

9 is a flowchart for explaining the operation of the control circuit of FIG.

[Explanation of symbols]

 1 ... Private branch exchange 2A to 2D ... Base station 3A to 3C ... Cordless telephone 4 ... Computer 5 ... Display device 11 ... Transmitting / receiving device 12 ... Transmitter 13 ... Handset 14 ・ ・ ・ Baseband circuit section 15 ・ ・ ・ Reception level detection section 16 ・ ・ ・ Operation key section 17 ・ ・ ・ Display section 18 ・ ・ ・ Control circuit 181 ・ ・ ・ Correspondence information section 182 ・ ・ ・ Comparison section 183 ・..Determination unit 19 ... Memory 20 ... Antenna 50 ... Personal computer 60 ... Control circuit 61 ... Memory 62 ... Display device

Claims (16)

[Claims] 1. A cordless telephone system comprising a switching center, a plurality of base stations connected to the switching center, and at least one cordless telephone for wirelessly communicating with these base stations, comprising: Each of the plurality of base stations has means for transmitting a signal including a base station identification code indicating its own base station, and the cordless telephone includes the base station identification code transmitted from each base station. Estimating the nearest base station based on the detection means for detecting the reception level of the signal, the reception level of each reception signal detected by the detection means, and the base station identification code included in each reception signal And a position estimating device for a cordless telephone in a cordless telephone system. 2. The position estimating device for a cordless telephone in a cordless telephone system according to claim 1, wherein the cordless telephone further comprises a display unit for displaying the estimated nearest base station. 3. The estimating means, for each reception signal, means for generating paired information which is a pair of the detected reception level and a base station identification code included in the reception signal corresponding to the reception level. , A means for selecting pair information having a maximum reception level from a plurality of pair information and estimating the base station indicated by the base station identification code of the selected pair information as the nearest base station. The position estimating device for a cordless telephone in the cordless telephone system according to claim 1. 4. The cordless telephone sends means for adding the telephone identification code of its own cordless telephone to the pair information, and the pair information to which the telephone identification code is added to the exchange through an arbitrary base station. The switching center selects a pair of information having a maximum reception level from the plurality of pair of information, and a cordless telephone of a cordless telephone indicated by a telephone identification code added to the selected pair of information. 4. The position of the cordless telephone in the cordless telephone system according to claim 3, further comprising display means for displaying that the nearest base station is the base station indicated by the base station identification code of the selected pair information. Estimator. 5. The selecting means is means for receiving pair information from a plurality of cordless telephones and selecting pair information having a maximum reception level for each pair information of each cordless telephone, and the display means is each cordless. It is means for displaying, for each telephone, that the base station closest to the cordless telephone indicated by the telephone identification code added to the selected pair information is the base station indicated by the base station identification code of the selected pair information. A position estimating device for a cordless telephone in the cordless telephone system according to claim 4. 6. A cordless telephone system comprising a switching center, a plurality of base stations connected to the switching center, and at least one cordless telephone that wirelessly communicates with these base stations, comprising: Each of the plurality of base stations has means for transmitting a signal including a base station identification code indicating its own base station, and the cordless telephone includes the base station identification code transmitted from each base station. Detection means for detecting the reception level of the signal, and the detected reception level for each reception signal,
A means for generating paired information with the base station identification code included in the received signal corresponding to this received level as a pair, and the paired information with the largest received level is selected from the plurality of paired information and selected. A means for estimating the base station indicated by the base station identification code of the pair information as the nearest base station, a display means for displaying the estimated nearest base station, and a cordless telephone handset of itself for the plurality of generated pair information. A means for adding an identification code, and means for transmitting the pair information to which the telephone identification code is added to the exchange through an arbitrary base station, wherein the exchange has the received pair information. The selection means for selecting pair information having the highest reception level from among them, and the base station of the cordless telephone indicated by the telephone identification code added to the pair information, are the base station identification codes of the pair information selected by the selection means. Group represented by Display means for displaying that it is a ground station,
A position estimating apparatus for a cordless telephone in a cordless telephone system, comprising: 7. The switching center selecting means is means for receiving pair information from a plurality of cordless telephones and selecting pair information having a maximum reception level for each pair of cordless telephones. 7. The position estimating device for a cordless telephone in a cordless telephone system according to claim 6, wherein the display means is a means for displaying a base station closest to each cordless telephone. 8. A position of a cordless telephone in a cordless telephone system including an exchange, a plurality of base stations connected to the exchange, and at least one cordless telephone that wirelessly communicates with these base stations. An estimation method, in each base station, transmitting a signal including a base station identification code indicating its own base station, and in a cordless telephone, a signal including the base station identification code transmitted from each base station And a step of estimating the nearest base station based on the reception level of each reception signal and the base station identification code included in each reception signal in the cordless telephone. A method for estimating the position of a cordless telephone in a cordless telephone system. 9. The method of estimating the position of a cordless telephone in a cordless telephone system according to claim 8, further comprising the step of displaying the estimated nearest base station in the cordless telephone. 10. The step of estimating the nearest base station includes, for each received signal, a pair of a received level of the received signal and a base station identification code included in the received signal corresponding to the received level. And a step of selecting the one having the highest reception level from the plurality of pair information and making the base station indicated by the base station identification code of the selected pair information the nearest base station. 9. The method for estimating the position of a cordless telephone in a cordless telephone system according to claim 8, further comprising: 11. A cordless telephone, wherein pair information to which a telephone identification code indicating its own cordless telephone is added is transmitted to an exchange through an arbitrary base station, and among the pair information received at the exchange. , The step of selecting the pair information having the highest reception level, and the exchange identifying the base station of the selected pair information as the nearest base station of the cordless telephone indicated by the telephone identification code added to the selected pair information. 11. The method for estimating the position of a cordless telephone in a cordless telephone system according to claim 10, further comprising the step of displaying a base station indicated by a code. 12. An exchange station, a plurality of base stations connected to the exchange station, at least one or more cordless telephones that wirelessly communicate with these base stations, and at least one or more information processing devices. In the cordless telephone system, each of the plurality of base stations has means for transmitting a signal including a base station identification code indicating its own base station, and the cordless telephone is transmitted from each base station. Detecting means for detecting the reception level of the signal including the base station identification code, and the detected reception level for each reception signal,
A pair of base station identification code included in the received signal corresponding to this reception level, and means for generating pair information, the information processing device, means for receiving the pair information from the cordless telephone, Means for selecting pair information having the maximum reception level from the received pair information and displaying that the base station closest to the cordless telephone is the base station indicated by the base station identification code of the selected pair information. Means and
A position estimating apparatus for a cordless telephone in a cordless telephone system, comprising: 13. The cordless telephone transmits means for adding a telephone identification code of its own cordless telephone to pair information, and pair information to which the telephone identification code is added, to an exchange through an arbitrary base station. The switching center is indicated by a telephone identification code added to the selected pair information and a selection means for selecting the pair information having the maximum reception level from the plurality of received pair information. 13. The cordless telephone system according to claim 12, further comprising display means for displaying that the base station closest to the cordless telephone is a base station indicated by the base station identification code of the selected pair information. Position estimation device for cordless phones. 14. The selecting means is means for receiving pair information from a plurality of cordless telephones and selecting pair information having a maximum reception level for each pair of cordless telephones, and the display means is for each cordless telephone. By means of displaying, for each telephone, the base station closest to the cordless telephone indicated by the telephone identification code added to the selected pair information is the base station indicated by the base station identification code of the selected pair information. The position estimating device for a cordless telephone in the cordless telephone system according to claim 13, wherein 15. An exchange station, a plurality of base stations connected to the exchange station, at least one or more cordless telephones that perform wireless communication with these base stations, and at least one or more information processing devices. A method for estimating the position of a cordless telephone in a cordless telephone system, comprising: transmitting a signal containing a base station identification code indicating its own base station to each of a plurality of base stations; Receiving a signal including the base station identification code transmitted from the device, and detecting the reception level; in the cordless telephone, the detected reception level for each reception signal and the reception signal corresponding to this reception level Generating pair information including a base station identification code included in the pair information, and the pair information from the cordless telephone in the information processing device. A step of receiving, in the information processing apparatus, a step of selecting pair information having a maximum reception level from the received pair information, and in the information processing apparatus, as a base station closest to the cordless telephone that has transmitted the pair information, And a display unit that displays a base station indicated by the base station identification code of the selected pair information, and a position estimating method for a cordless telephone in a cordless telephone system. 16. A cordless telephone, wherein the telephone identification code of its own cordless telephone is added to the pair information, and the cordless telephone exchanges the pair information to which the telephone identification code is added, via an arbitrary base station. To the exchange, the step of selecting the pair information with the highest reception level from the received pair information at the exchange, and the cordless code indicated by the telephone identification code added to the selected pair information at the exchange. 16. The position estimation of the cordless telephone in the cordless telephone system according to claim 15, further comprising the step of displaying a base station indicated by the base station identification code of the selected pair information as a base station closest to the telephone. Method.