TWI412262B - Mobile communication system and method for determining distance between two mobile phones - Google Patents

Abstract

A method determining a distance between two mobile phones includes: choosing a Base Transceiver Station (BTS) acting as a primary BTS, obtaining first positioning information of a first mobile phone relative to the primary BTS, obtaining second positioning information of a second mobile phone relative to the primary BTS, calculating the distance between the first mobile phone and the second mobile phone according to the first positioning information and the second positioning information. A corresponding mobile communication system is provided as well.

Description

Method for measuring distance between mobile phone users and mobile communication system

The present invention relates to a distance measuring method and system, and more particularly to a method and a mobile communication system for measuring the distance between mobile phone users.

The mobile phone communicates by interacting with a Base Transceiver Station (BTS). As shown in FIG. 1, a mobile communication system 100 includes a plurality of base stations 102 that are typically arranged in the form of a distribution of cells 104. The mobile phone 106 is enclosed in the cell 104, and the base station 102 enclosing the corresponding cell 104 assumes the service of interacting with the mobile phone 106. When the mobile phone 106 is moved from one cell to another, the corresponding service is also switched from the previous base station to the base station enclosing the new cell. Thus, by interacting with the base station 102, mobile communication is enabled between the mobile phones 106.

The location of the mobile phone user can be calculated based on the location of the cell in which the mobile phone user is located and the base station surrounding the cell. As shown in FIG. 2, in the mobile communication system 200, a user of the mobile phone 210 to be located transmits a positioning command, which is transmitted to the adjacent three base stations 202, 204, 206, and by using the base station. Connected base station control center (Base The Station Controller (BSC) is transmitted to the Mobile Switching Center (MSC). Calculating the time difference according to different times when the command arrives at the three base stations, and obtaining the distances S1, S2, and S3 between the mobile phone 210 and each of the base stations 202, 204, and 206, since the positions of the base stations are known to be fixed, The location of the mobile phone 210 can be determined.

However, mobile phone users often not only want to know where they are, but also want to know the distance between themselves and another user.

In view of this, it is necessary to provide a method for measuring the distance between mobile phone users.

In addition, it is necessary to provide a mobile communication system that can measure the distance between mobile phone users.

A method for measuring a distance between mobile phone users, comprising: selecting a base station as a reference base station; acquiring first location information of the first mobile phone relative to the reference base station; acquiring a second mobile phone relative to the reference base station a second location message; calculating a distance between the first mobile phone and the second mobile phone based on the first and second location messages.

A mobile communication system comprising a base station and a mobile exchange for transmitting/receiving a communication signal of a mobile phone; the mobile exchange is configured to select a service base station from a service base station of the mobile phones as a reference base a platform, and calculating first and second location messages of the first and second mobile phones relative to the reference base station, thereby calculating between the first and second mobile phones according to the first and second location messages The distance.

The above method for measuring the distance between mobile phone users and the mobile communication system calculates the distance between the mobile phones by using the location information of the mobile phone relative to the base station, and satisfies the user's demand for distance measurement between the mobile phones.

300, 400, 900‧‧‧ mobile communication systems

302, 304, 306, 308, 402, 404, 406408, 410, 412, 902, 904, 906 ‧ ‧ base station

310, 320, 420, 430, 910, 920‧‧‧ mobile phones

552‧‧‧Request mobile phone

556, 600‧‧‧ mobile switches

554‧‧‧Requested Base Station Control Center

558‧‧‧Requested Base Station Control Center

560‧‧‧Requested mobile phone

S502~S534‧‧‧Digital measurement signaling process

602‧‧‧ message receiving/transmitting module

604‧‧‧ register

606‧‧‧Location Area Database

608‧‧‧Operation processor

S702~S728‧‧‧Signaling process for processing distance measurement service requests

The flow of the distance calculated by the S802~S822‧‧‧ computing processor

FIG. 1 is a schematic structural diagram of a mobile communication system.

2 is a schematic diagram of a mobile communication system for user positioning.

3 is a schematic structural diagram of a mobile communication system according to a preferred embodiment.

4 is a schematic structural diagram of a mobile communication system according to another preferred embodiment.

FIG. 5 is a schematic structural diagram of a mobile communication system according to another preferred embodiment.

6 is a signaling flow chart of a distance measurement of a mobile communication system according to a preferred embodiment.

FIG. 7 is a schematic structural diagram and a signaling flowchart of a distance calculation performed by a mobile switch according to a preferred embodiment.

FIG. 8 is a detailed flow chart of the calculation processor 608 shown in FIG. 7 calculating the distance between the two mobile phones based on the location information of the two mobile phones.

As shown in FIG. 3, a mobile communication system 300 of a preferred embodiment includes a plurality of Base Transceiver Stations (BTS) 302, 304. 306, 308, the mobile phones 310, 320 in the encirclement of the base stations can communicate with the base station. The base stations 302, 304, 306, 308 enclose two adjacent location areas, wherein the base stations 304, 306 are service base stations common to the mobile phones 310, 320.

When calculating the distance between the two mobile phones 310, 320, the base station 304 is determined to be the reference base station, and the base station 306 is determined to be the reference base station. The location of the mobile phone 310 can be achieved by the base stations 302, 304, 306, that is, when the mobile phone 310 issues a positioning request, the Mobile Switching Center (MSC) connected to the base stations 302, 304, 306 will calculate the distance from the positioning requirements of the mobile phone 310 and the reference base station 304 L _1, the distance between the reference base station 306 L _2; Similarly, the operation switch may also be calculated by mobile phone 320 and the reference base station 304 The distance L ₃ between the distance L ₃ and the reference base station 306 is L ₄ .

When the mobile communication service provider sets the base station, the distance D ₁ between the reference base station 304 and the reference base station 306 is determined, and thus the distance between the mobile phone 310 and the reference base station 304 can be determined according to the distance D ₁ . The distance L ₂ between the L ₁ and the reference base station 306 calculates the angle θ ₁ between the mobile phone 310 and the reference base station 306 with respect to the reference base station 304. The specific calculation method may adopt a cosine theorem, namely: Thus, you can get:

Similarly, the angle θ ₂ between the mobile phone 320 and the reference base station 306 relative to the reference base station 304 can also be calculated, namely:

The angle formed by the mobile phones 310 and 320 with respect to the reference base station 304 is θ ₁ + θ ₂ , and thus, the distance X ₁ between the mobile phone 310 and the mobile phone 320 can be calculated by the following formula:

As shown in FIG. 4, another preferred embodiment of the mobile communication system 400 includes a plurality of base stations 402, 404, 406, 408, 410, and 412 surrounded by base stations 402, 404, and 406. In the location area, the mobile telephone 430 is enclosed in a location area enclosed by the base stations 408, 410, and 412. The locations of the two location areas enclosed by the base stations are not adjacent, so there is no common service base station between the mobile phones 420, 430.

Similar to the previous embodiment, when calculating the distance between the two mobile phones 420, 430, the base station 402 is determined as the reference base station, the base station 406 is determined as the first reference base station, and the base station 408 is determined to be the first Second reference base station. The mobile phone 420 can be located by the adjacent three base stations 402, 404, 406, and the distance L ₁ ' between the base station 402 and the reference base station 402 can be obtained, and the mobile phone 420 and the first reference base station can also be obtained. 406 is at an angle θ ₁ ' with respect to the base base station 402. Similarly, the mobile phone 430 can be located by the adjacent three base stations 408, 410, 412, and obtained with the second reference base station 408. The distance L ₂ 'and the mobile phone 430 and the base station 410 are at an angle θ ₂ ' with respect to the second reference base station 408.

When the mobile communication service provider sets up the base station, the distance D ₁ ' between the reference base station 402 and the second reference base station 408 is determined, and the reference base station 402 and the base station 410 are formed relative to the second reference base station 408. the angle θ _3, with reference to the first base station 406 and the second base station 408 with respect to the reference base station 402 to the base of an angle θ _4, and thus the distance between the mobile phone 402 and the reference base station 430 L ₃ 'according to the following Formula to determine: At the same time, the angle θ ₅ formed by the mobile phone 430 and the second reference base station 408 with respect to the reference base station 402 can also be determined according to the following formula:

Thus, applying the cosine theorem to the triangle formed by the reference base station 402, the mobile phone 420, and the mobile phone 430 can determine the distance X ₁ ' between the mobile phones 420 and 430, which can be expressed as:

As shown in FIG. 5, in another embodiment of the mobile communication system 900, two mobile phones 910, 920 are in the same grid surrounded by base stations 902, 904, 906, then base stations 902, 904 906 is a service base station for mobile phones 910 and 920, respectively. In this case, the distance between the mobile phones 910, 920 is calculated in a similar manner to the embodiment shown in FIG. 3: the base station 904 is determined to be the reference base station, and the base station 906 is the reference base station, whereby the mobile phone 910, The distance between the 920 X ₁ " can be expressed as:

It can be seen from the above three implementation manners that the distance measurement between the two mobile phones is achieved by selecting one of the plurality of service base stations of the two mobile phones as the reference base station (for example, the base station 304 in FIG. 3, The base station 402 in FIG. 4 and the base station 904 in FIG. 5 are calculated by the reference base station and the triangle enclosed by the two mobile phones, so that the distance between the two mobile phones can be obtained.

However, if the relative positions of the location areas of the two mobile phones are different, the process of calculating the distance is different. If the two mobile phones are located adjacent to each other, the two mobile phones have at least two common service base stations. (e.g., base stations 304, 306 in Figure 3, or base stations 904, 906 in Figure 5), then only one common serving base station (e.g., base station 304 in Figure 3, base station in Figure 5) 904) as the above reference base station, additionally selecting a common service base station (for example, 306 in FIG. 3, base station 906 in FIG. 5) as a reference base station, and the two mobile phones are in common with the two mobile phones. The location information of the service base station can calculate the distance between the two mobile phones. If the location areas of the two mobile phones are not adjacent, and the two mobile phones do not have a common service base station, then a service base station (such as base station 402 in Figure 4) must be selected as the reference base station. Each service base station of each mobile phone serves as a reference base station (for example, base station 406, 408 in FIG. 4), and calculates two relative position information based on two mobile phones, two reference base stations, and one reference base station. The distance between the mobile phones.

The following is an example of the mobile communication system shown in FIG. 4, which illustrates the working principle of the distance measurement by the mobile communication system. When the mobile phone 420 proposes a distance measurement with the mobile phone 430, the Mobile Switching Center (MSC) connected to the base station in the area where the mobile phone (ie, the mobile phone 420) is located is requested by the base station on the requested side. The Base Station Controller (BSC) sends a service request to the requested mobile phone (i.e., mobile phone 430). After receiving the service request, the mobile phone 430 can request the service to send a response message according to the actual situation, and the response message is sent to the mobile switch. If the response message of the mobile phone 430 indicates that the requested mobile phone 430 agrees to perform the distance measurement, the mobile switch root Calculate the location of the two mobile phones based on the regional information of the two mobile phones 420 and 430, and further calculate the distance between the two mobile phones based on the location information of the two mobile phones, and calculate the calculated distance by the base. The station control center sends a request to the mobile phone 420 to complete a service. If the response message of the mobile phone 430 indicates that the requested mobile phone 430 does not agree to perform the distance measurement, the base station control center BSC sends a reject message to the requesting mobile phone 420 via the mobile exchange MSC.

As shown in FIG. 6, it is a signaling flow chart for distance measurement of a mobile communication system of a preferred embodiment.

In step S502, the requesting mobile phone 552 transmits a distance measurement request (REQ) to the base station control center 554 on the request side.

In step S504, the requesting side base station control center 554 forwards the distance measurement request REQ to the mobile exchange (MSC) 556.

In step S506, the mobile exchange 556 notifies the requesting side base station control center 554 to send a test signal to the requesting mobile phone 552.

In step S508, the feedback message requesting the mobile phone 552 is forwarded to the mobile exchange (MSC) 556 by the base station control center 554 on the request side.

Step S510, the mobile exchange (MSC) 556 calculates a location message requesting the mobile phone 552 according to the feedback message, where the location information includes the distance between the requesting mobile phone 552 and the adjacent base station, and the adjacent base station. Relative angle and so on.

In steps S512 to S514, the distance measurement request (REQ) is finally transmitted to the requested mobile phone 560 by the transfer of the mobile exchange (MSC) 556 and the requested side base station control center 558.

In step S516, the requested mobile phone 560 responds to the distance measurement request and sends a corresponding response message (RSP) to the base station control center 558 on the requested side.

In step S518, the response message RSP is forwarded to the mobile exchange (MSC) 556 by the base station control center 558 on the requested side.

In step S520, the mobile exchange (MSC) 556 determines that the response message RSP indicates whether the requested mobile phone 560 accepts the distance measurement request.

Step S522, if the response message indicates that the requested mobile phone 540 does not agree to perform the distance measurement, the mobile exchange (MSC) 556 sends a rejection signal to the requesting mobile phone 552 by the requesting side base station control center 554.

Step S524, if the response message indicates that the requested mobile phone 540 agrees to perform the distance measurement, the mobile exchange (MSC) 556 notifies the requested side base station control center 558 to send the test signal to the requested mobile phone 560.

In step S526, the feedback message of the requested mobile phone 560 is forwarded to the mobile exchange (MSC) 556 by the base station control center 558 on the requested side.

Step S528, the mobile exchange (MSC) 556 calculates a location message of the requested mobile phone 560 according to the feedback message, where the location information includes the distance between the requested mobile phone 560 and the adjacent base station, and the adjacent base station. between The relative angle and so on.

In step S530, the mobile exchange (MSC) 556 calculates the distance between the two mobile phones based on the location message requesting the mobile phone 552 and the location information of the requested mobile phone 560.

In steps S532-S534, the mobile exchange (MSC) 556 sends a result (RST) to the base station control center 554 on the request side, and forwards it to the requesting mobile phone 552 via the requesting side base station control center 554.

As shown in FIG. 7, it is a schematic structural diagram of distance calculation inside a mobile switch (MSC). The mobile exchange (MSC) 600 includes a message receiving/transmitting module 602, a temporary register 604, a location area database 606, and an arithmetic processor 608.

The message receiving/transmitting module 602 is configured to receive a service request for requesting a mobile phone forwarded by the base station control center on the requesting side, a feedback message for the test message, and forward the service request for requesting the mobile phone to the base station control of the requested side. center. The message receiving/transmitting module 602 is further configured to receive a response message of the requested mobile phone forwarded by the base station control center on the requested side, a feedback message for the test message, and the like.

The operation processor 604 is configured to calculate a location information of the mobile phone, the feedback message of the requested mobile phone for the test message, and calculate the distance between the two mobile phones according to the location information.

The register 606 is used to register the request mobile phone, the location information of the requested mobile phone, and the intermediate data generated by the arithmetic processor 608 when performing the distance calculation.

The location area database 608 stores the location area data of each mobile phone. When the location area where the mobile phone is located changes, the location area data stored in the location area database 608 is also updated immediately.

The signaling flow of the mobile switch 600 processing the service request for distance measurement will be described below.

Step S702, the base station control center on the request side transmits a service request for distance measurement of the mobile phone to the message receiving/transmitting module 602.

In step S704, the message receiving/transmitting module 602 sends a test signal to the base station control center on the request side, and the test signal is forwarded to the requesting mobile phone by the requesting side base station control center.

In step S706, the message receiving/transmitting module 602 receives the feedback message of the requesting mobile phone requested by the requesting base station control center for the test signal, and transmits the feedback message to the operation processor 604.

Step S708, the operation processor 604 calculates a location message requesting the mobile phone according to the feedback message, and registers the location message requesting the mobile phone in the temporary register 606.

In step S710, the message receiving/transmitting module 602 forwards the service request message requesting the mobile phone to the base station control center on the requested side.

Step S712, after the requested mobile phone responds to the service request, the message receiving/transmitting module 602 receives the response message of the requested mobile phone forwarded from the base station control center of the requested side, and will be requested to the mobile phone. Respond The message is passed to the arithmetic processor 604.

In step S714, the operation processor 604 determines whether the response message indicates that the requested mobile phone agrees to the service request of the distance measurement.

Step S716: If the response message indicates that the requested mobile phone does not agree with the service request, the message receiving/transmitting module 602 sends a rejection message to the requesting base station control center.

Step S718, if the response message indicates that the requested mobile phone agrees to perform the distance measurement, the message receiving/transmitting module 602 sends a test signal to the requested base station control center, and the test signal is forwarded to the called side base station control center. Request a mobile phone call.

In step S720, the message receiving/transmitting module 602 receives the feedback message of the requested mobile phone forwarded by the requested base station control center for the test signal, and transmits the feedback message to the operation processor 604.

Step S722, the operation processor 604 calculates a location message of the requested mobile phone according to the feedback message, and registers the location message of the requested mobile phone in the temporary register 606.

In step S724, the operation processor 604 reads the location information of the two mobile phones from the temporary memory 606, and calculates the distance between the two mobile phones based on the location information of the two mobile phones to generate a calculation result.

Steps S726~S728, the operation processor 604 transmits the calculation result to the message receiving/transmitting module 602, and the message receiving/transmitting module 602 transfers the calculation result to the requesting side. The base station control center then sends the calculation result to the requesting mobile phone through the requesting side base station control center, thereby completing a service service.

As shown in FIG. 8, it is a detailed process for the arithmetic processor 604 to calculate the distance between the two mobile phones according to the location information of the two mobile phones.

Step S802, if the mobile phone user is requested to agree to the service request for the distance measurement, the operation processor 604 reads the location information of the two mobile phones from the temporary memory 606.

In step S804, the operation processor 604 performs an inquiry in the location area database 608 according to the location information of the two mobile phones to determine the location area where the two mobile phones are located.

In step S806, the location area database 608 returns the query result to the operation processor 604, that is, the location area information of the two mobile phones respectively.

In step S808, the operation processor 604 determines whether the two mobile phones have two common service base stations according to the location area information of the two mobile phones. If the two mobile phones have two service base stations in common, step S810 is performed; if there are no two common service base stations, step S816 is performed.

Step S810, if the two mobile phones have two common service base stations, select one of the common service base stations as the reference base station (for example, the base station 304 in FIG. 3), and then select a common service base station as the base station. Reference base station (e.g., base station 306 in Figure 3).

Step S812, the mobile phone is determined relative to the position of the two posts of the reference base station, the location message comprising the mobile phone and the distance between two of the reference base station (referred to as L _1, L ₃₎ and two mobile phone And refer to the angle formed by the base station with respect to the reference base station (set to θ ₁ , θ ₂ ).

Step S814, calculating the distance between the two mobile phones (set to X ₁ ) according to the location information of the two mobile phones relative to the reference base station, and the specific calculation formula may be: or Thus, the business service of a distance measurement is completed.

In step S814, which of the two calculation formulas is used as the calculation formula determines whether the two mobile phones are in the same grid, and whether the two mobile phones are in the same grid can be the actual positions of the two mobile phones. The message is judged.

Step S816, if the two mobile phones do not have two common service base stations, then one service base station of one of the mobile phones (hereinafter referred to as the first mobile phone) is selected as the reference base station and the other service base station as the first Referring to the base station; another service base station of another mobile phone (hereinafter referred to as the second mobile phone) is selected as the second reference base station.

Step S818, the first mobile phone is determined relative to the reference base station of the post, the post comprising a distance between the position of the first mobile phone and the reference base station (referred to as L ₁ ') and the first mobile phone, the first The angle between the reference base station and the reference base station (set to θ ₁ ').

Step S820, the second mobile phone is calculated relative to the posts of the reference base station, the message comprising a distance between the position of the second mobile phone and the reference base station (referred to as L ₃ ') and the second mobile phone, the first The angle of the reference base station relative to the reference base station (set to θ ₅ ).

Step S822, calculating the distance between the two mobile phones (set to X ₁ ') according to the location information of the first mobile phone and the second mobile phone relative to the reference base station, and the specific calculation formula may be: Where θ ₄ is the angle formed by the first reference base station and the second reference base station relative to the reference base station. Thus, the business service of a distance measurement is completed.

The method for measuring the distance between the mobile phone users and the mobile communication system, after receiving the service request from the requesting side, if the consent response of the requested mobile phone is obtained, the location information of the received mobile phone relative to the base station To calculate the distance between mobile phones. The invention satisfies the user's demand for distance measurement between mobile phones; and does not need to change the existing network, and can use the existing mobile communication network to add a new service to the network operator. Service; since the above process is implemented on the core network circuit domain device, the stability of the service is high.

In summary, the present invention complies with the requirements of the invention patent and submits a patent application according to law. However, the above is only a preferred embodiment of the present invention, and those skilled in the art will be able to include the equivalent modifications or variations in the spirit of the present invention.

300‧‧‧Mobile communication system

310, 320‧‧‧ mobile phones

302, 304, 306, 308‧‧‧ base station

Claims (14)

A method for measuring a distance between mobile phone users, comprising: determining whether there are two or more common service base stations between the first mobile phone and the second mobile phone; and between the first and second mobile phones When there are no two or more service base stations: one service base station of the first mobile phone is selected as the reference base station, and another service base station of the first mobile phone is selected as the first reference base station, and is selected. a service base station of the second mobile phone is a second reference base station; acquiring a first location message of the first mobile phone relative to the reference base station, the first location message including the first mobile phone and the reference base station a first distance between the first mobile phone and the first reference base station relative to the reference base station; acquiring second position information of the second mobile phone relative to the reference base station, the second position The message includes a second distance between the second mobile phone and the reference base station, and the second mobile phone and the second reference base station are relative to the reference a second angle formed by the platform; obtaining a third angle formed by the first reference base station and the second reference base station relative to the reference base station; calculating according to the first and second position information and the third angle The distance between the first mobile phone and the second mobile phone. A method of measuring the distance between mobile phone users as described in claim 1 wherein: when there are two or more common between the mobile phones The service base station further includes: selecting one of the common service base stations as the reference base station, and selecting another common service base station as the reference base station; obtaining the first position of the first mobile phone relative to the reference base station Information, the first location information includes a first distance between the first mobile phone and the reference base station, and a first angle formed by the first mobile phone, the reference base station relative to the reference base station; a second location message of the mobile phone relative to the reference base station, the second location message including a second distance between the second mobile phone and the reference base station, and the second mobile phone, the reference base station relative to the a second angle formed by the reference base station; calculating a distance between the first mobile phone and the second mobile phone based on the first and second location messages. The method for measuring the distance between mobile phone users according to claim 1, wherein the method further comprises: forwarding a service request for distance measurement sent by the first mobile phone to the second mobile phone; receiving the second mobile phone A response message to the service request; determining whether the response message indicates whether the second mobile phone agrees to the service request; and if the response message indicates that the second mobile phone agrees to the service request, selecting a base station as the reference base station. The method for measuring the distance between mobile phone users as described in claim 3, wherein: the method further comprises: if the response message indicates that the second mobile phone does not agree with the service request, sending a rejection message to the first mobile phone. A mobile communication system includes a base station and a mobile exchange for transmitting/receiving a communication signal of a mobile phone; the mobile exchange is configured to determine whether there are two or two between the first mobile phone and the second mobile phone The above-mentioned common service base station; and when there is no two or more service base stations between the first and second mobile phones, one service base station of the first mobile phone is selected as the reference base station, and is selected Another service base station of the first mobile phone is a first reference base station, and one service base station of the second mobile phone is selected as a second reference base station; and the first mobile phone is obtained first with respect to the reference base station a first location information including a first distance between the first mobile phone and the reference base station and a first angle formed by the first mobile phone and the first reference base station relative to the reference base station; Second location information of the second mobile phone relative to the reference base station, the second location message including the second mobile phone and the reference base station a second distance and a second angle formed by the second mobile phone and the second reference base station relative to the reference base station; acquiring the first reference base station and the second reference base station relative to the reference base station a third angle; calculating a distance between the first mobile phone and the second mobile phone according to the first and second location messages and the third angle. The mobile communication system according to claim 5, wherein the mobile switch comprises a message receiving/transmitting module, an arithmetic processor and a location area database, and the message receiving/transmitting module can receive the first action a location area message of the second mobile phone, the operation processor is configured to perform an inquiry in the location area database according to the location area information, to determine whether the first and second mobile phone service base stations are in the service base station There is a common service base station. The mobile communication system of claim 6, wherein: if the service base stations of the first and second mobile phones have two or more service base stations, the mobile switch performs the operation The processor selects one of the common service base stations of the common service base station as the reference base station, and the other common service base station is the reference base station; calculates the first position of the first mobile phone relative to the reference base station Information, the first location information includes a first distance between the first mobile phone and the reference base station, and a first angle formed by the first mobile phone and the reference base station relative to the reference base station; a second location message of the mobile phone relative to the reference base station, the second location message including a second distance between the second mobile phone and the reference base station, and the second mobile phone, the reference base station relative to the a second angle formed by the reference base station; and calculating a distance between the first mobile phone and the second mobile phone according to the first and second location messages. The mobile communication system of claim 6, wherein: if there is no two or more common service base stations in the service base stations of the first and second mobile phones, the mobile exchange is The operation processor selects one service base station of the first mobile phone as the reference base station, and selects another service base station of the first mobile phone as the first reference base station and one service base station of the second mobile phone a second reference base station; and calculating, by the operation processor, a first angle formed by the first mobile phone and the first reference base station relative to the reference base station, the second mobile phone and the second reference base a second angle formed by the station relative to the reference base station and a second distance between the second mobile phone and the reference base station. The mobile communication system of claim 8, wherein: the line The dynamic switch is further used by the computing processor to calculate a first distance between the first mobile phone and the reference base station. The mobile communication system of claim 9, wherein: the mobile switch is further configured by the arithmetic processor according to the first reference base station and the second reference base station relative to the reference base station The distance between the first and second mobile phones is calculated from the three angles, the first location information, and the second location message. The mobile communication system according to claim 6, wherein: the message receiving/transmitting module is configured to receive a service request of the first mobile phone sent by the base station on the requesting side, and forward the service request The base station on the requested side, whereby the base station on the requested side can send the service request to the requested second mobile phone. The mobile communication system of claim 11, wherein the message receiving/transmitting module is further configured to receive a response message of the second mobile phone sent by the base station on the requested side. The mobile communication system of claim 12, wherein: the operation processor is configured to determine, according to the response message, whether the second mobile phone agrees to the service request; if the response message indicates that the second mobile phone agrees to The service request calculates the distance between the first and second mobile phones. The mobile communication system of claim 13, wherein: if the response message indicates that the second mobile phone does not agree with the service request, the message receiving/transmitting module sends a rejection message to the first mobile phone.