JPH11178042A - Position detection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a mobile station small in scale and to enhance the convenience of the position detection system in which a position is detected, not depending on reception of a radio wave of a GPS. SOLUTION: This system is provided with plural base stations 210 connecting with an electric communications network, a mobile station 110 that makes communications with the base stations, a reception level detection means 216 each installed in plural base stations to detect Q reception level of a radio wave from the mobile station, a distance detection means 217 that obtains each distance between the mobile station and the base stations, and a position detection means 500 that detects the position of the mobile station, based on the respective distances between the mobile station and plural base stations obtained by the distance means. The plural base stations 210 measure reception levels of radio waves from the mobile station 110 so that the distance between each of the plural base stations and the mobile station are obtained. The position of the mobile station 110 is detected based on the distances. Thus, positions are detected without receiving a radio wave from a GPS. That is, it is not required to provide a receiver to receive the radio wave of the GPS to the mobile station, and the size of the mobile station can be made small and the operational cost of the mobile station is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for detecting a current position of a mobile station using a mobile communication system having indoor and outdoor service areas.

[0002]

2. Description of the Related Art As a position detection system for detecting the position of a moving object, a GPS (Global) has conventionally been used.
Positioning System (Global Positioning System). In this position detection system, a signal from a GPS satellite is received, and this signal is demodulated to obtain information on the latitude and longitude of the position of the moving object at the reception point. Further, in this type of apparatus, a map is generally displayed on a display device using map information stored in a memory in advance, and a current position is displayed on the map. Further, in order to improve the reliability of position detection, the position information measured by the GPS satellite signal may be corrected by referring to the map information.

[0003]

In the conventional position detection system, a signal from a GPS satellite is received, and the position is determined by referring to map information. Therefore, a GPS radio wave receiving apparatus becomes large and expensive. There is a problem that becomes.
Therefore, it is inconvenient for a person to carry and carry a receiving device or the like for position detection. In addition, there is a problem that position detection becomes impossible in places where it is difficult to receive GPS radio waves, such as indoors and underground malls. Further, even outdoors, there is a problem that the position detection accuracy is degraded due to the shielding of GPS radio waves by high-rise buildings.

The present invention relates to a position detecting system, comprising:
It is an object of the present invention to enable position detection without receiving a PS radio wave, to reduce the size of a mobile station and improve convenience.

[0005]

According to a first aspect of the present invention, there is provided a position detecting system comprising: a plurality of base stations connected to a predetermined telecommunications network; and first wireless communication means provided in each of the plurality of base stations. A mobile station having second wireless communication means and capable of communicating with the base station, and a reception level detection apparatus installed on each of the plurality of base stations and detecting a reception level of a radio wave from the mobile station. Means, distance detection means for obtaining a distance between the mobile station and the base station from the reception level detected by the reception level detection means, and each of the mobile station and the plurality of base stations obtained by the distance detection means And a position detecting means for detecting the position of the mobile station based on a distance to the base station and a position of each base station, and display means for displaying information on the position detected by the position detecting means. I do.

That is, at a plurality of base stations, the reception levels of radio waves from the mobile station are measured, and the distance between the plurality of base stations and the mobile station is obtained. Based on these distances, the position of the mobile station is detected. Therefore, position detection can be performed without receiving GPS radio waves. That is, there is no need to provide a receiver for receiving GPS radio waves in the mobile station, and the mobile station can be reduced in size and economical.

[0007] Since the position of the base station is fixed, information on the position where each base station exists can be obtained as needed. The position detecting means detects the position of the mobile station based on the position of the base station and the distance. According to a second aspect of the present invention, in the position detection system according to the first aspect, each of the base stations transmits at least one of an identification code of the base station and information on the location of the base station to the position detection means. It is characterized by comprising information sending means.

The position detecting means detects the position of the mobile station using the position information of the base station transmitted from each base station.
Alternatively, the position of each base station is specified based on the identification information transmitted from each base station, and the position of the mobile station is detected based on the position of the base station. According to a third aspect of the present invention, in the position detection system according to the second aspect, the base station information transmitting means transmits a mobile station identification code transmitted from the mobile station to be detected to the base station to the position detecting means. And

The position detecting means can specify one mobile station based on the mobile station identification code transmitted from the base station. That is, even if there are a plurality of mobile stations, the position can be detected for each mobile station. Claim 4
The position detecting system according to claim 1, further comprising a first display unit connected to the telecommunication network as the display unit.

[0010] The position of the mobile station can be displayed on the first display means connected to the telecommunications network. Therefore, it is convenient to monitor the position of the mobile station. According to a fifth aspect of the present invention, in the position detection system according to the first aspect, a second display unit mounted on the mobile station is provided as the display unit, and the position detection unit transmits information on the detected position to the base station. And transmitting position information to the mobile station via the mobile station.

[0011] The second display means on the mobile station can display its own position. Therefore, it is convenient for a person carrying the mobile station to grasp the current position.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a position detecting system embodying the present invention is shown in FIGS. This form corresponds to all claims.

FIG. 1 is a block diagram showing the main components of the position detection system. FIG. 2 is a block diagram showing a configuration of a mobile station of the position detection system of FIG. FIG.
FIG. 2 is a block diagram showing a configuration of a base station of the position detection system of FIG. FIG. 4 is a block diagram showing a configuration of a position detection station of the position detection system of FIG. FIG. 5 is a block diagram showing a process for assigning a mobile station to one base station. FIG. 6 is a map showing a data configuration of a table generated on the position detecting station.

FIG. 7 is a plan view showing the positional relationship between a plurality of base stations and mobile stations. FIG. 8 is a flowchart showing a mobile station detection process of each base station. FIG. 9 is a flowchart showing the position detecting process of the position detecting station. In this embodiment, the base station according to claim 1 includes the base stations 210, 230,
The mobile stations are embodied as 250 and 270, and the mobile stations are embodied as mobile stations 110, 130, 150 and 170.

The first wireless communication means, the second wireless communication means, the reception level detection means, the distance detection means and the position detection means according to claim 1 are a high-frequency circuit 212, a high-frequency circuit 112, and a reception level detection circuit, respectively. 216, control unit 217 (step S13) and control unit 512
This is embodied as (Step S25). Further, the display means of the present invention is embodied as the display unit 120, the display unit 219, and the display device 600.
Further, the base station information transmitting means of claim 2 and the first of claim 4
Display means, second display means of claim 5, and claim 5
The position information transmitting means of the control unit 217
(Steps S14, S15), Display Device 600, Display Unit 120, Control Unit 512 (Step S26)
It is embodied as

First, the overall configuration of the position detection system will be described with reference to FIG. This system uses the mobile station 11
0, 130, 150 and 170 and base stations 210 and 23
0, 250, and 270, a line control station 300, a telecommunications network 400, a position detection station 500, and a display device 600. In this example, four mobile stations and four base stations are shown, but in an actual system, the number of mobile stations and the number of base stations are increased or decreased as necessary.

Base stations 210, 230, 250 and 270
Are connected to a telecommunications network 400 via a line control station 300. Further, the line control station 300 is connected to the position detection station 500 and the display device 600. The wireless zones Z1, Z2, Z3 and Z4 are respectively
10, 230, 250, and 270 means a range in which wireless communication is possible. The mobile stations 110, 130, 150 and 170 are connected to at least one of the radio zones Z1 to Z4.
Base station 210, 230, 25
Wireless communication (transmission and reception) is possible with any one of 0 and 270.

Base stations 210, 230, 250 and 270
Are connected to the telecommunications network 400 via the line control station 300, so that the mobile stations 110, 130, 150 and 17
0 can communicate with various terminal devices (not shown) connected to the telecommunications network 400. Mobile station 11
Each of 0, 130, 150 and 170 is a base station 2
It is registered in any one of 10, 230, 250, and 270, and performs wireless communication with the registered base station.

Mobile stations 110, 130, 150 and 170
Is registered in the base stations 210, 230, 250 and 270 under the control of the line control station 300 as shown in FIG. This will be described with reference to FIG. First, mobile station 1
Base stations 210 and 23 capable of receiving radio waves from
0, 250, and 270 detect the reception level of the radio wave from the mobile station 110, respectively. Each base station that has detected the reception level sends the reception level, the mobile station identification code, and the base station identification code to the line control station 300.

The line control station 300 specifies the base station having the highest reception level by comparing the input reception levels of the base stations. An instruction is given to this one base station to register the mobile station 110 corresponding to the mobile station identification code. The base station instructed to register registers itself with the mobile station 110 corresponding to the mobile station identification code, and notifies the mobile station 110 of the result of the registration.

In the position detection system shown in FIG. 1, when detecting the position of mobile station 110, base stations 210 and 2
Each of 30, 250, and 270 receives the transmission radio wave of the mobile station 110, and detects the reception level and the identification code of the mobile station. Then, each base station sends the data of the reception level together with the identification code of the mobile station and the identification code of the base station (the latitude / longitude data of the installation position of the base station may be used) to the position detection station 500 via the line control station 300. Transfer to

As shown in FIG. 6, the position detecting station 500 stores, for each mobile station, the latitude / longitude data of each base station, the base station identification code, the reception level, and the data of the distance between the base station and the mobile station. Be stacked. The position detecting station 500 detects the position of each mobile station based on these data. The latitude / longitude data of the mobile station obtained by the position detection is transmitted from the position detection station 500 to the display device 60 connected to the telecommunications network 400.
0 and is displayed on the display device 600.
Further, the latitude / longitude data of the mobile station obtained by the position detection is transferred to the mobile station 110 via the base station having the highest reception level among the base stations 210, 230, 250, and 270, and is transmitted to the mobile station 110. Also the position is displayed.

As shown in FIG. 2, the mobile station 110 includes an antenna 111, a high-frequency circuit 112, a modulation / demodulation circuit 113, a communication information processing circuit 114, a codec 115, a speaker 1
16, microphone 117, control unit 118, storage circuit 1
19, a display unit 120 and a map data storage unit 121. Other mobile stations 130, 150, 17
The configuration of 0 is the same as that of the mobile station 110.

For example, a signal transmitted from base station 210 is received by antenna 111, converted to a low-frequency signal by high-frequency circuit 112, demodulated by modulation / demodulation circuit 113, and decoded by communication information processing circuit 114. The audio information included in the communication channel in the received signal of the mobile station 110 is D / A converted by the codec 115 and output from the speaker 116 as an analog signal. Also, the mobile station 11
0, various data included in the control channel are transmitted from the communication information processing circuit 114 to the control unit 118.
Is input to

The control unit 118 is a device incorporating a microcomputer, and performs various controls. The data input to the control unit 118 is stored in the storage circuit 11
9 and read as needed. The map data storage unit 121 holds map information including a position where the mobile station 110 exists. When the location information of the mobile station is input to the mobile station 110 via the base station 210 or the like, a map near the current location of the mobile station 110 and a mark indicating the current location are displayed under the control of the control unit 118. Displayed above.

The audio signal input from the microphone 117 is
The data is A / D converted by the codec 115 and applied to the communication information processing circuit 114 as a digital signal. This digital signal is encoded as a signal of the communication channel,
It is output from the communication information processing circuit 114. The signal output from the communication information processing circuit 114 is modulated by the modulation / demodulation circuit 113, converted into a high-frequency signal by the high-frequency circuit 112, and transmitted as a radio wave from the antenna 111. The control channel of the signal to be transmitted includes data (for example, a mobile station identification code) output from the control unit 118.

As shown in FIG. 3, the base station 210 includes an antenna 211, a high-frequency circuit 212, a modulation / demodulation circuit 213, a communication information processing circuit 214, a codec 215, a reception level detection circuit 216, a control unit 217, and a storage circuit 21.
8, a display unit 219 and a map database 220 are provided. The configuration of other base stations 230, 250, and 270 is the same as base station 210.

For example, a signal transmitted from the mobile station 110 is received by the antenna 211, converted into a low-frequency signal by the high-frequency circuit 212, demodulated by the modulation / demodulation circuit 213, and decoded by the communication information processing circuit 214. Of the received signals of the base station 210, audio information included in the communication channel is D / A converted by the codec 215 and output as an analog signal from a speaker (not shown). Various data included in the control channel among the received signals of the base station 210 are transmitted from the communication information processing circuit 214 to the control unit 2.
17 is input.

One output of the high frequency circuit 212 is
The signal is input to the reception level detection circuit 216. The reception level detection circuit 216 outputs the output level of the high frequency circuit 212, that is, the reception level proportional to the intensity of the received radio wave, to the control unit 217 as a digital signal. The reception level detected by the reception level detection circuit 216 is a component of one of the control channel and the communication channel of the signal.

The control unit 217 is a device incorporating a microcomputer, and performs various controls. The data input to the control unit 217 is stored in the storage circuit 21
8 and read as needed. When the reception level detection circuit 216 measures the reception level, the control unit 217 detects the mobile station identification code included in the control channel of the received signal at the same time. The reception level and the corresponding mobile station identification code are 1
The data is stored in the storage circuit 218 as a pair of data.

FIG. 8 shows the contents of the mobile station detection process periodically executed under the control of the control unit 217. Next, the contents of the processing shown in FIG. 8 will be described. Base station 2
10 detects, for example, a signal from the mobile station 110,
The process of the control unit 217 proceeds to step S11 through step S10 in FIG. In step S11, the reception level of the radio wave from the mobile station 110 is measured. At about the same time, step S12 is executed.
In step S12, the mobile station identification code included in the control channel of the received signal is detected.

In step S13, based on the reception level measured in step S11, the base station 210 and the mobile station 1
Calculate the distance r to 10. Distance between base station and mobile station,
The reception level, propagation attenuation constant, transmission output, and transmission / reception antenna gain at the base station are represented by r, Pr, α, and Pt, respectively.
And A, the following first equation holds.

Pr = Pt + A−10 · α · 1 log (r) (1) In the first equation, the reception level Pr, the propagation attenuation constant α, the transmission output Pt, and the transmission / reception antenna gain A at the base station.
Is known in the base station 210, the distance r between the base station and the mobile station can be obtained from the first equation. In step S14 of FIG. 8, the base station identification code assigned to the base station 210 in advance is read from the internal memory (ROM). In the next step S15, the reception level detected in step S11, the mobile station identification code detected in step S12, the distance r obtained in step S13, and step S14
Is transmitted as a set of data to the position detection station 500 via the line control station 300.

When the position of the mobile station is determined by the processing of the position detecting station 500 and the position information of the mobile station is input from the position detecting station 500 to the base station 210, the processing of the control unit 217 proceeds through step S16. Proceed to step S17. In step S17, the map data including the input position of the mobile station is read out from the map database 220 and displayed on the display unit 219, and the position of the mobile station is displayed on the map with a predetermined mark. In the next step S18, information indicating the position coordinates is transmitted to the mobile station 110 subjected to position detection.

The position detection station 500, as shown in FIG.
An interface circuit 511, a control unit 512, a storage circuit 513, and a base station position information storage unit 514 are provided. The interface circuit 511 is connected to the line control station 300. The control unit 512 is a control device having a built-in microcomputer, and mainly executes a position detection process of the mobile station.

The base station position information storage section 514 is constituted by a read-only memory (ROM), and includes a plurality of base stations 2.
The coordinate data of the installation positions of 10, 230, 250, and 270 are stored in advance in association with the respective base station identification codes. Next, the contents of the position detection processing executed by the processing of the control unit 512 will be described with reference to FIG. Note that the processing in FIG. 9 is periodically executed.

When the information of the mobile station arrives at the position detecting station 500 from each base station via the line control station 300, the processing of the control unit 512 proceeds to step S21 through step S20. That is, when information is input from the base station to the position detecting station 500 by the processing of step S15 shown in FIG. 8, the process proceeds to step S21. Utilizing the base station identification code included in the input information, the data in the base station position information storage unit 514 is referred to, and the position information of a specific base station is input. If the position information of the base station is directly input from the base station to the position detection station 500, the process proceeds to step S21.
May be omitted.

In the next step S22, a table T as shown in FIG.
Create BL. The table TBL is created for each mobile station. On each table TBL, a mobile station identification code and information on a base station number, a base station position (latitude and longitude), a base station identification code, a reception level, and a distance (r) between the base station and the mobile station are written. It is.

In the next step S23, if there are data from a plurality of base stations, the order of the contents of the table TBL is changed so that the data from each base station are arranged in descending order of the reception level. . For example, in the example of FIG. 6, as a result, the base station identification code is “JSGH001”.
Since the reception level (50 dBμV) at the base station “1” is the highest, the data of this base station is arranged first. Similarly, when the base station identification code is “FGYX003
8 ", the reception level (46 dBμV) at the base station is 2
The data of this base station is placed second since it is the second largest.

In this example, based on the principle of three-point distance measurement,
The mobile station position is detected. Therefore, to perform position detection, data from at least three base stations is required. When the data from the three base stations is prepared on the table for each mobile station, the position can be detected, and the process proceeds to step S25 via step S24.

In step S25, as shown in FIG.
A plurality of circles centering on the respective locations of three or more base stations are obtained, and their intersection points are detected as the positions of the mobile stations. That is, the (x, y) coordinates of the base station 1, the base station 2, and the base station 3 are (x1, y1), (x2,
y2) and (x3, y3), the distance between the base station 1 and the mobile station is r1, the distance between the base station 2 and the mobile station is r2, and the distance between the base station 3 and the mobile station is r3 , Each circle is represented by the following second equation.

[0042] ^{(x-x1) 2 + (} y-y1) 2 = r1 2, (x-x2) 2 + (y-y2) 2 = r2 2, (x-x3) 2 + (y-y3) 2 = R3 ² ... (2) By substituting the coordinates (x1, y1), (x2, y2) and (x3, y3) and the distances r1, r2 and r3 into the second equation, the intersection of three circles Are obtained (xa, ya). The coordinates of this intersection are detected as the location of the mobile station.

In step S26 of FIG. 9, step S2
The information on the position coordinates of the mobile station detected in step 5 is displayed on the display device 60.
0, and at the same time, to the specific base station where the mobile station is registered via the line control station 300. This position information is also transmitted to the mobile station via the base station. Therefore, each of the mobile station, the base station, and the display device 600 can display the position of the mobile station.

Although FIG. 7 shows the case where the number of base stations is three, even when information from four or more base stations is present, the intersection of four or more circles is obtained to obtain the mobile station. Can be obtained with higher accuracy.

[0045]

According to the present invention, the reception level is measured at the base station, and the distance between the base station and the mobile station is obtained from a calculation formula.
Since the position of the mobile station can be determined from the coordinates of the intersection of a circle having a radius equal to the distance between the base station and the mobile station, it is not necessary to equip the mobile station with a receiver for receiving GPS radio waves.

Accordingly, the size and economy of the mobile station can be reduced. Furthermore, position detection is possible even indoors where GPS radio waves cannot be received. Further, if the distance is calculated only by the base station and the position is displayed by the mobile station, the memory and the display unit of the map data for displaying the position of the base station can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing main components of a position detection system.

FIG. 2 is a block diagram showing a configuration of a mobile station of the position detection system of FIG.

FIG. 3 is a block diagram showing a configuration of a base station of the position detection system of FIG.

FIG. 4 is a block diagram showing a configuration of a position detection station of the position detection system of FIG.

FIG. 5 is a block diagram showing a process for assigning a mobile station to one base station.

FIG. 6 is a map showing a data configuration of a table generated on the position detection station.

FIG. 7 is a plan view showing a positional relationship between a plurality of base stations and a mobile station.

FIG. 8 is a flowchart showing a mobile station detection process of each base station.

FIG. 9 is a flowchart showing a position detecting process of the position detecting station.

[Explanation of symbols]

 110, 130, 150, 170 Mobile station 111 Antenna 112 High frequency circuit 113 Modulation / demodulation circuit 114 Communication information processing circuit 115 Codec 116 Speaker 117 Microphone 118 Control unit 119 Storage circuit 120 Display unit 121 Map data storage unit 210, 230, 250, 270 Base Station 211 antenna 212 high frequency circuit 213 modulation / demodulation circuit 214 communication information processing circuit 215 codec 216 reception level detection circuit 217 control unit 218 storage circuit 219 display unit 220 map database 300 line control station 400 telecommunication network 500 position detection station 511 interface circuit 512 control Unit 513 Storage circuit 514 Base station position information storage unit 600 Display device TBL table Z1, Z2, Z3, Z4 None Zone

Claims (5)

[Claims] 1. A base station comprising: a plurality of base stations connected to a predetermined telecommunications network; first wireless communication means provided in each of the plurality of base stations; and second wireless communication means. A mobile station capable of communicating with the mobile station; a reception level detection unit installed on each of the plurality of base stations to detect a reception level of a radio wave from the mobile station; and a reception detected by the reception level detection unit. Distance detecting means for determining a distance between the mobile station and the base station from a level, based on a distance between the mobile station and each of the plurality of base stations and an existing position of each base station obtained by the distance detecting means. A position detecting means for detecting the position of the mobile station; and a display means for displaying information on the position detected by the position detecting means. 2. The position detection system according to claim 1, wherein each of said base stations sends at least one of an identification code of said base station and information on the location of said base station to said position detection means. A position detection system comprising information sending means. 3. The position detecting system according to claim 2, wherein said base station information transmitting means transmits a mobile station identification code transmitted from the mobile station to be detected to the base station to said position detecting means. And position detection system. 4. The position detection system according to claim 1, further comprising a first display unit connected to said telecommunication network as said display unit. 5. The position detection system according to claim 1, further comprising a second display unit mounted on said mobile station as said display unit, wherein said position detection unit transmits information on the detected position to said base station. A position information transmitting means for transmitting the position information to the mobile station via the mobile station.