JP2004254229A - Location positioning system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a location positioning system in which a location of a mobile machine is grasped on the basis of information from one base station when positioning cannot be performed by a global positioning system. <P>SOLUTION: The location positioning system 10 for positioning the location of a mobile telephone set 30 having a function with which the global positioning system is utilized to position its own location, includes: a positioning judgement part 102 for judging whether the mobile telephone set 30 can utilize the global positioning system for positioning; and a location specifying part 103 for specifying the location resulting from positioning by the mobile telephone set 30 as a location of the mobile telephone set 30 when the judged result indicates that positioning is possible, and specifying the location of the mobile telephone set 30 on the basis of distance information and area information for specifying a distance between the base station corresponding to the mobile telephone set 30 and the mobile telephone set 30 when the judged result indicates positioning is impossible. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a position identification system.
[0002]
[Prior art]
As a method of measuring the own position, a global positioning system (GPS) is used. This global positioning system receives radio waves from four GPS satellites, calculates the distance from each GPS satellite, and calculates the position. However, since this global positioning system uses radio waves from GPS satellites at a distance of more than 20,000 km from the earth, positioning cannot be performed in places where radio waves from GPS satellites are blocked such as indoors or behind buildings. There were challenges. In particular, this problem is remarkable when the global positioning system is used in a portable information terminal such as a mobile device. In order to solve this problem, there has been proposed a method of specifying a position in a place where positioning cannot be performed by the global positioning system by using the electric field strength of a radio wave from a base station corresponding to a mobile device (for example, Patent Document 1). reference.).
[0003]
[Patent Document 1]
JP 2000-348297 A
[Problems to be solved by the invention]
In the related art, information obtained from one base station is information indicating that the mobile station exists on a circle having a radius equal to a predetermined distance from the base station. Therefore, there is a problem to be solved such that information must be acquired from a plurality of base stations in order to accurately grasp the position of the mobile device.
[0005]
In view of the above, an object of the present invention is to provide a position specifying system that can grasp the position of a mobile device based on information obtained from one base station when positioning cannot be performed by the global positioning system.
[0006]
[Means for Solving the Problems]
The position specifying system of the present invention is a position specifying system for specifying the position of a mobile device having a function of specifying its own position using a global positioning system. Positioning area storing means for storing area information indicating an available area and an impossible area; and a positioning judging means for judging whether the mobile station can perform positioning using the global positioning system. If the result of the determination is that positioning is possible, the position determined by the mobile device is specified as the position of the mobile device.If the result of the determination is that positioning is not possible, the base station and mobile device corresponding to the mobile device are identified. And position specifying means for specifying the position of the mobile device based on the distance information and the area information for specifying the distance of the mobile device.
[0007]
According to the position specifying system of the present invention, when the mobile device cannot perform positioning using the global positioning system, the position is determined based on the distance information and the region information for specifying the distance between the base station and the mobile device. Is specified, the position of the mobile device can be specified even in a place where the global positioning system cannot be used, such as in a building. In addition, when a region that can be positioned and a region that cannot be positioned using the global positioning system are dispersedly distributed, it can be estimated that the mobile device exists in a region on an equidistant circle.
[0008]
In the position specifying system of the present invention, it is preferable that the distance information includes information indicating the electric field strength of a radio wave transmitted from the base station to the mobile device. Since the electric field strength changes according to the distance from the base station, if the area that can be located and the area that cannot be located using the global positioning system are dispersedly distributed, It can be estimated that the mobile device exists in the area on the line.
[0009]
In the position specifying system of the present invention, the distance information is a time interval between the time when the base station transmits the inspection signal to the mobile station and the time when the base station receives a response signal returned from the mobile station in response to the inspection signal. It is also preferable to include information indicating a distance calculated based on the information. Radio waves, which are transmission media for test signals and response signals, are not easily affected by obstacles, and if the distance is calculated based on this time, the distance between the base station and the mobile device can be grasped more accurately.
[0010]
In the position specifying system of the present invention, it is preferable that the area information includes visible satellite information indicating how many satellites of the global positioning system can be seen for each area. Based on the visible satellite information, it is possible to accurately determine whether or not the mobile device is in a state where positioning is possible using the global positioning system.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
The findings of the present invention can be readily understood by considering the following detailed description with reference to the accompanying drawings shown by way of example only. Subsequently, embodiments of the present invention will be described with reference to the accompanying drawings. When possible, the same parts are denoted by the same reference numerals, and redundant description will be omitted.
[0012]
A position identification system according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a diagram for explaining the position identification system 10. The position identification system 10 is configured to be able to mutually communicate with a mobile phone (mobile device) 30 via a network 20. The mobile phone 30 is a mobile phone used by a user who uses the position identification system 10. The mobile phone 30 is configured to be able to measure its own position using a GPS (Global Positioning System). When the user using the mobile phone 30 inputs a command for positioning the own location, the mobile phone 30 transmits a positioning request including the number of visible GPS satellites and information indicating the distance to each GPS satellite to the position specifying system 10. . The positioning request further includes the ID of the base station that is currently communicating with the mobile phone 30 and the electric field strength of the radio wave transmitted from the base station.
[0013]
Subsequently, the position specifying system 10 will be described. The position identification system 10 is physically a computer system (or computer) including a CPU (Central Processing Unit), a memory, an input device such as a mouse and a keyboard, a display device such as a display, a storage device such as a hard disk, and a communication device such as a modem. System).
[0014]
The position specifying system 10 includes, as functional components, a receiving unit 101, a positioning determining unit (position determining unit) 102, a position specifying unit (position specifying unit) 103, a transmitting unit 104, a positioning area storage unit ( Positioning area storage means) 110 and a base station information storage unit 111. Subsequently, each component will be described in detail.
[0015]
The receiving unit 101 is a unit that receives a positioning request transmitted from the mobile phone 30 and outputs the request to the positioning determining unit 102. As described above, this positioning request is input by the user of the mobile phone 30 and includes information indicating the number of visible GPS satellites and the distance to each GPS satellite. The positioning request further includes the ID of the base station that is currently communicating with the mobile phone 30 and the electric field strength of the radio wave transmitted from the base station.
[0016]
The positioning determination unit 102 is a part that determines whether the mobile phone 30 can perform GPS positioning. More specifically, based on the number of GPS satellites visible to mobile phone 30 included in the positioning request output from receiving section 101, it is determined whether or not mobile phone 30 can perform GPS positioning. For example, if the number of visible GPS satellites is three or more, it is determined that GPS positioning is possible, and if the number is two or less, it is determined that GPS positioning is impossible. The positioning determination unit 102 outputs the determination result to the position identification unit 103 together with the positioning request.
[0017]
If the determination result output from positioning determining section 102 indicates that GPS positioning is possible, position specifying section 103 determines the position of mobile phone 30 based on information indicating the distance to each GPS satellite included in the positioning request. To identify. On the other hand, if the determination result output from the positioning determination unit 102 indicates that GPS positioning is impossible, the area information stored in the positioning area storage unit 110 and the area information stored in the base station information storage unit 111 are stored. The position of the mobile phone 30 is specified based on the base station information. The area information stored in the positioning area storage unit 110 is information indicating an area where positioning is possible using GPS and an area where positioning is not possible. The base station information stored in the base station information storage unit 111 is information indicating the position of each base station.
[0018]
FIG. 2 shows an example of the area information. The area information 40 is information for specifying an area on the map where GPS positioning is possible and an area where GPS positioning is not possible. According to the example of FIG. 2, since the GPS positioning cannot be performed in the buildings 50, 51, 54, and 55, the buildings are recognized in black on the map. An area 52 where three GPS satellites can see through near the building 50, an area 53 where only two GPS satellites can see through near the building 51, and three GPS satellites near the building 54 can see. In the vicinity of the building 55, there are regions 57 in which only two GPS satellites can be seen. In the case of the example of FIG. 2, a region other than the building and in which the region is not particularly specified is a region where four GPS satellites can see through.
[0019]
FIG. 3 shows an example of base station information. According to the example of FIG. 3, the base station ID and the position information are stored in correspondence. Therefore, if the ID of the base station corresponding to the mobile phone 30 is 001, its position is 135 ° 20'30 ″ east longitude and 38 ° 20′55 ″ latitude north. Since the base station ID is sent together with the electric field strength from the mobile phone 30, the base station 60 and the equal electric field strength line 60a centered on the base station 60 can be drawn as shown in FIG. Therefore, if the number of GPS satellites that can be seen by the mobile phone 30 is two or less, it means that the mobile phone 30 is in the area 53 or the area 57, but it is specified that the mobile phone 30 is in the area 53 from the relationship with the isoelectric field intensity line 60a. The information indicating the specified position of the mobile phone 30 is output to the transmitting unit 104.
[0020]
The transmitting unit 104 is a unit that transmits the information indicating the position of the mobile phone 30 output from the position specifying unit 104 to the mobile phone 30.
[0021]
Subsequently, a method for specifying a position using the position specifying system 10 will be described with reference to a flowchart shown in FIG. The user using the mobile phone 30 transmits a positioning request to the position identification system 10. The positioning request is received by the receiving unit 101 of the position identification system 10 (Step S01). The receiving unit 101 outputs the received positioning request to the positioning determining unit 102.
[0022]
The positioning determination unit 102 determines whether or not the mobile phone 30 can perform GPS positioning based on the number of GPS satellites that the mobile phone 30 can see (step S02). The positioning determination unit 102 outputs the determination result to the position identification unit 103 together with the positioning request. If the determination result in step S02 indicates that GPS positioning is possible, the position specifying unit 103 specifies the position of the mobile phone 30 based on information indicating the distance to each GPS satellite included in the positioning request (step S03). ). The position specifying unit 103 outputs information indicating the position of the specified mobile phone 30 to the transmitting unit 104. The transmitting unit 104 transmits this information to the mobile phone 30 (Step S08).
[0023]
If the result of the determination in step S02 is that GPS positioning is not possible, the position specifying unit 103 specifies the base station currently corresponding to the mobile phone 30 based on the base station ID transmitted from the mobile phone 30. (Step S04). Further, based on the electric field strength transmitted from the mobile phone 30, the position specifying unit 103 specifies an equi-field strength line from the corresponding base station (step S05).
[0024]
The position specifying unit 103 specifies an area where the mobile phone 30 exists based on the number of line-of-sight GPS satellites transmitted from the mobile phone 30 (step S06). The position specifying unit 103 specifies the position of the mobile phone 30 based on the results of steps S04 to S06 as illustrated in FIG. 2 (step S07). The position specifying unit 103 outputs information indicating the position of the specified mobile phone 30 to the transmitting unit 104. The transmitting unit 104 transmits this information to the mobile phone 30 (Step S08).
[0025]
A position specifying program 92 for causing a computer to function as the position specifying system of the present embodiment and a computer-readable recording medium 9 on which the program is recorded will be described. FIG. 5 is a diagram showing a configuration of the recording medium 9 on which the position specifying program 92 is recorded. Examples of the recording medium 9 include a magnetic disk, an optical disk, a CD-ROM, and a memory built in a computer.
[0026]
As shown in FIG. 5, the recording medium 9 includes a program area 91 for recording a program and a data area 93 for recording data. The data area 93 stores a positioning area database 931 similar to the positioning area storage unit 110 described with reference to FIG. 1 and a base station information database 932 similar to the base station information storage unit 111, respectively.
[0027]
In the program area 91, a position specifying program 92 is recorded. The position specifying program 92 includes a main module 921 for controlling the processing, a receiving module 922, a positioning determining module 923, a position specifying module 924, and a transmitting module 925. Here, the functions realized by operating each of the receiving module 922, the positioning determining module 923, the position specifying module 924, and the transmitting module 925 are the receiving unit 101, the positioning determining unit 102, and the position specifying unit of the position specifying system 10. The functions are the same as those of the transmission unit 103 and the transmission unit 104.
[0028]
According to the present embodiment, when the mobile device cannot perform positioning using the GPS, the position is specified based on the electric field strength of the radio wave from the base station and the area information. The position of the mobile phone 30 can be specified even in a place where the system cannot be used. In addition, since the electric field intensity changes according to the distance from the base station, as shown in FIG. 2, when the area that can be measured using GPS and the area that cannot be measured are distributed in a distributed manner. Can be presumed that the mobile phone 30 exists in an area on the isoelectric field strength line.
[0029]
In the case of the present embodiment, the distance between the base station and the mobile phone 30 is specified based on the electric field strength, but the embodiment of the present invention is not limited to this. For example, based on the time from when the base station transmits a test signal to the mobile phone 30 to when the base station receives a response signal returned from the mobile phone 30 to the test signal, the base station and the mobile phone 30 May be determined. The radio wave, which is a transmission medium for the inspection signal and the response signal, is not easily affected by obstacles. If the distance is calculated based on this time, the distance between the base station and the mobile phone 30 can be grasped more accurately.
[0030]
Preferably, the area information includes visible satellite information indicating how many satellites of the global positioning system can be seen for each area. Based on the visible satellite information, it is possible to accurately determine whether or not the mobile device is in a state where positioning is possible using the global positioning system.
[0031]
【The invention's effect】
According to the present invention, when the mobile device cannot perform positioning using the global positioning system, the position is specified based on the distance information and the area information for specifying the distance between the base station and the mobile device. For example, the position of the mobile device can be specified even in a place where the global positioning system is not available, such as in a building. In addition, when a region that can be positioned and a region that cannot be positioned using the global positioning system are distributed in a distributed manner, it can be estimated that the mobile device exists in a region on an equidistant circle. Accordingly, it is an object of the present invention to provide a position specifying system and a position specifying program that can grasp the position of a mobile device based on information obtained from one base station when positioning by a global positioning system cannot be performed. did it.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a position identification system according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of information stored in a positioning area storage unit in FIG. 1;
FIG. 3 is a diagram illustrating an example of information stored in a base station information storage unit in FIG. 1;
FIG. 4 is a flowchart showing a method for specifying the position of the mobile phone using the position specifying system.
FIG. 5 is a diagram for explaining a position specifying program according to the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Position specifying system, 101 ... Receiving part, 102 ... Positioning determination part, 103 ... Position specifying part, 104 ... Transmission part, 110 ... Positioning area storage part, 111 ... Base station information storage part, 20 ... Network, 30 ... Mobile Phone.

Claims (4)

A location identification system for identifying the position of a mobile device having a function of identifying its own position using a global positioning system, and an area where positioning is possible and an area where positioning is impossible using a global positioning system And positioning area storage means for storing area information indicating
Positioning determination means for determining whether positioning is possible or impossible using the global positioning system by the mobile device,
If the result of the determination is that positioning is possible, the position determined by the mobile device is specified as the position of the mobile device.If the result of the determination is that positioning is not possible, the base station corresponding to the mobile device and the Position specifying means for specifying the position of the mobile device based on the distance information and the area information for specifying the distance to the mobile device,
Positioning system including. The position specifying system according to claim 1, wherein the distance information includes information indicating an electric field intensity of a radio wave transmitted from the base station to the mobile device. The distance information is calculated based on the time from when the base station transmits a test signal to the mobile station to when the base station receives a response signal returned from the mobile station in response to the test signal. The location system of claim 1, comprising information indicating a distance to be performed. The position specifying system according to claim 1, wherein the area information includes visible satellite information indicating how many satellites of the global positioning system can be seen for each area.

Images