JP4951089B2 - Positioning support apparatus and positioning support method - Google Patents

Description

  The present invention relates to a positioning support apparatus that transmits approximate position information used as assist data in positioning calculation by a communication terminal to a communication terminal and a positioning support method by the positioning support apparatus.

  Along with the improvement in performance of communication terminals such as mobile phones, communication terminals having a positioning function using GPS (Global Positioning System) are spreading. When performing a positioning calculation using GPS in a communication terminal, there is a concern that the positioning time may be prolonged and the power consumption in the communication terminal may be increased in a single positioning method in which only a radio wave from a GPS satellite is received for positioning. For this reason, a network assist method is adopted that shortens positioning time by transmitting capture information (assist data) such as the position of a GPS satellite from a positioning support server to a communication terminal. Also, in network-assisted GPS positioning, as information indicating the approximate position of a communication terminal (approximate position information), information that specifies the position of a base station in an area where the communication terminal is located is one of assist data. Is transmitted from the positioning support server to the communication terminal (see, for example, Patent Document 1). The approximate position information of the communication terminal is information that greatly contributes to the success rate of GPS positioning.

JP 2008-175824 A

  However, if the base station where the communication terminal is located is not that of the own network, for example, when roaming out to an overseas mobile communication network, information specifying the position of the base station where the communication terminal is located May not be grasped by the positioning support server. In this case, the positioning support server calculates the approximate position information from limited information such as information specifying the country in which it is transmitted from the communication terminal and transmits it to the communication terminal. Accuracy is reduced. For this reason, there existed a problem that the success rate of the GPS positioning by a communication terminal fell.

  The present invention has been made in view of the above, and an object of the present invention is to provide a positioning support apparatus that transmits high-precision approximate position information to a communication terminal, and a positioning support method using the positioning support apparatus.

  In order to achieve the above object, a positioning support apparatus according to the present invention is used for positioning calculation in a communication terminal that captures a satellite and performs positioning using information from the satellite, and a communication area in which the communication terminal is located Including the approximate position information storing means for storing the approximate position information indicating the location of the communication and the information specifying the communication area in association with each other, and the information specifying the communication area where the communication terminal is located. Based on the positioning information transmission request, the approximate position information that is stored in the approximate position information storage means in association with the information that identifies the communication area in which the communication terminal is located is acquired and transmitted to the communication terminal. A positioning result receiving means for receiving positioning result information that is transmitted from the communication terminal that has acquired the approximate position information transmitted by the approximate position information transmitting means and that indicates the result of the positioning calculation; A position information update means for updating the approximate position information stored in the approximate position information storage means based on the position result information, and the positioning result information includes success / failure information indicating whether the positioning operation has succeeded or failed. And the satellite number information indicating the number of satellites captured by the communication terminal in the positioning calculation, and the approximate position information update means determines whether the approximate position information is defective based on the success / failure information and the satellite number information. Then, based on the result, the approximate position information transmitted to the communication terminal among the approximate position information stored in the approximate position information storage means is initialized.

  According to the above positioning support device, the positioning result information transmitted from the communication terminal is received, and based on this positioning result information, the approximate position information stored in the approximate position information storage means and indicating the position of the communication area is updated. Is done. As described above, since the accuracy of the approximate position information can be increased based on the results of positioning by the communication terminal, it is possible to transmit the approximate position information with higher accuracy to the communication terminal. In addition, when the positioning calculation by the communication terminal fails, the approximate position information update unit has a failure in the approximate position information transmitted to the communication terminal based on the success / failure information and the satellite number information captured by the communication terminal. The approximate position information is initialized based on the result. Thus, by having the aspect which initializes the approximate position information determined to be defective, it is possible to prevent a decrease in positioning accuracy due to continuing the positioning calculation using the approximate position information determined to be defective. Also, by using the satellite number information to determine whether the approximate position information is defective, for example, if the positioning calculation fails due to insufficient acquisition of the satellite by the communication terminal, the approximate position information Can be prevented from being initialized, unnecessary initialization of the approximate position information can be suppressed, and more accurate approximate position information can be provided.

  Here, as a configuration that effectively achieves the above-described operation, specifically, the approximate position information update unit is information indicating that the success / failure information has failed in the positioning calculation, and the number of satellites specified by the satellite number information is It is determined whether or not it is greater than a predetermined value, and if the success / failure information is information indicating that the positioning operation has failed and the number of satellites is greater than the predetermined value, the approximate position information transmitted to the communication terminal is defective. A mode of initializing the approximate position information transmitted to the communication terminal among the approximate position information stored in the approximate position information storage means when the number of times determined to be defective and the number of times determined to be defective exceeds a threshold value Is mentioned.

  Further, the approximate position information is information for specifying the position of the base station in the communication area, and the approximate position information and the positioning result information may be information including latitude and longitude.

  Furthermore, the approximate position information update means can use an aspect that uses information specifying the position of a base station management apparatus that manages a plurality of base stations including the base station as new approximate position information after initialization. .

  As described above, the approximate position information is information for specifying the position of the base station in the communication area, and the information for specifying the position of the base station management apparatus that manages a plurality of base stations including the base station is newly added. By using it as position information, even if the approximate position information is initialized, it is prevented that the position of the communication area where the communication terminal is located and the approximate position information after initialization are largely separated, A decrease in positioning accuracy can be prevented.

  In addition, the approximate position information update unit calculates new approximate position information based on the position specified by the approximate position information transmitted to the communication terminal and the position specified by the positioning result information. be able to.

  As described above, it is more appropriate to calculate new approximate position information based on the position specified by the approximate position information transmitted to the communication terminal and the position specified by the positioning result information, and Highly accurate approximate position information is newly calculated.

  The approximate position information storage means stores a flag indicating whether or not the approximate position information needs to be updated in association with the approximate position information, and the approximate position information update means needs to update the approximate position information based on the flag. When it is determined that there is, it is possible to update the approximate position information.

  If the approximate position information stored in the approximate position information storage means is accurate information, there is a possibility that the accuracy of the approximate position information may be lowered by updating based on the positioning result by the communication terminal. is there. Therefore, by storing the flag indicating whether update is necessary in association with the approximate position information, it is possible to prevent the accuracy of the approximate position information from being lowered.

  The present invention can be described as the invention of the positioning support apparatus as described above, and can also be described as the invention of the positioning support method as follows. This is substantially the same invention only in different categories, and has the same operations and effects.

  That is, the positioning support method according to the present invention is used for positioning calculation in a communication terminal that acquires a satellite and performs positioning using information from the satellite, and indicates a position of a communication area where the communication terminal is located. A positioning support method by a positioning support apparatus comprising approximate position information storage means for storing position information and information for specifying the communication area in association with each other, and communication in which a communication terminal is located by the approximate position information transmission means Based on the positioning information transmission request transmitted from the communication terminal including information for specifying the area, the approximate position information stored in the approximate position information storage means in association with the information for specifying the communication area in which the communication terminal is located is The approximate position information transmission step to be acquired and transmitted to the communication terminal, and the communication terminal that has acquired the approximate position information transmitted by the approximate position information transmitting means perform the positioning calculation to perform the communication. The positioning result receiving step for receiving positioning result information, which is information indicating the result of the positioning calculation transmitted from the terminal, is stored in the approximate position information storage means based on the positioning result information by the approximate position information updating means. A positioning information update step for updating the positioning information, and positioning result information includes success / failure information indicating whether the positioning calculation has succeeded or failed, and the number of satellites indicating the number of satellites captured by the communication terminal in the positioning calculation In the approximate position information update step, it is determined whether or not the approximate position information is defective based on the success / failure information and the number of satellites information, and is stored in the approximate position information storage means based on the result. Of the approximate position information, the approximate position information transmitted to the communication terminal is updated to an initial value.

  ADVANTAGE OF THE INVENTION According to this invention, the positioning assistance apparatus which transmits approximate position information with high precision with respect to a communication terminal, and the positioning assistance method by the said positioning assistance apparatus are provided.

It is a block diagram explaining the structure of the positioning system which concerns on suitable embodiment of this invention. It is a figure which shows the hardware constitutions of a SUPL server, a positional information management apparatus, a user information management apparatus, a GW apparatus, and a base station apparatus. It is a figure which shows the hardware constitutions of a communication terminal. It is an example of the approximate position information stored in the approximate position information DB. It is an example of the positional information on SGSN stored in rough position information DB. It is an example of the information stored in management DB. It is a sequence diagram explaining the process for communicating between a communication terminal and a SUPL server. It is a sequence diagram explaining the process which concerns on the authentication process of the communication terminal in a mobile communication network, and the preparation regarding the approximate position information transmitted with respect to a communication terminal. It is a flowchart explaining the process which determines the transmission data transmitted with respect to a SUPL server in a positional infomation management apparatus. It is a flowchart explaining the process which determines the positional information used as rough positional information transmitted with respect to a communication terminal from a SUPL server. It is a flowchart explaining the process which determines the positional information used as rough positional information transmitted with respect to a communication terminal from a SUPL server. It is a sequence diagram explaining the process which concerns on GPS positioning in a communication terminal, and the process after positioning. It is a flowchart explaining the process at the time of updating approximate position information in a SUPL server.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

<Configuration of positioning system including positioning support system>
FIG. 1 is a block diagram illustrating a configuration of a positioning system 1 according to a preferred embodiment of the present invention. The positioning system 1 includes a SUPL (Secure User Plane Location) server 20 and a location information management device 30, a user information management device 40, a GW (Gateway) device 50, a communication terminal 60, and a base that constitute the positioning support system 10. And a station device 70. Among these, the positioning support system 10 including the SUPL server 20 and the location information management device 30 is a device that supports the positioning calculation by the communication terminal 60, and includes the user information management device 40, the GW device 50, and the base station device 70. Are apparatuses related to communication between the communication terminal 60 and the positioning support system 10, respectively. The SUPL server 20, the location information management device 30, the user information management device 40, and the GW device 50 are devices included in the same mobile communication network, and the communication terminal 60 is connected to the mobile communication network N1. Has a function to connect. In the present embodiment, the communication terminal 60 is in a state of roaming out from the mobile communication network N1, for example, when used overseas, and is included in the mobile communication network N2 different from the mobile communication network N1. Communication is performed by connecting to the base station device 70 to be connected. At this time, a case where the communication terminal 60 performs positioning upon receiving assistance data from the positioning support system 10 included in the mobile communication network N1 will be described.

  Here, a positioning method performed by the communication terminal 60 in the present embodiment will be described. In the present embodiment, the positioning method performed by the communication terminal 60 is GPS (Global Positioning System) positioning by a network assist method. GPS positioning refers to the position of the receiving terminal (communication terminal 60) (specifically, latitude, longitude and altitude) based on the positional information of the GPS satellite by receiving signals from three or more GPS satellites in the sky. In order to do this, it is necessary to capture a GPS satellite by the communication terminal 60, and this process takes a certain time. For this reason, in the GPS positioning by the network assist method according to the present embodiment, information (assist data) such as the position of the GPS satellite and the approximate position (initial position) information of the communication terminal 60 is transmitted from the positioning support system 10 to the communication terminal. By transmitting, the processing related to the acquisition of GPS satellites by the communication terminal 60 and the shortening of the positioning time are achieved. In this embodiment, when the communication terminal 60 requests the positioning support system 10 to provide assist data, information indicating the approximate position of the communication terminal 60 and the position of the GPS satellite from which the communication terminal 60 can receive a signal. By receiving information from the positioning support system 10, GPS positioning is performed by the communication terminal 60 and the position of the communication terminal 60 is obtained.

  Among the assist data sent from the positioning support system 10 to the communication terminal 60, the position information of the GPS satellite is from an assist data provider (not shown) that manages the activation information of the GPS satellite in the positioning support system 10. The acquired information is used. On the other hand, as the approximate position information of the communication terminal 60, the position information of the base station device that transmits radio waves to the cell that is the communication area in which the communication terminal 60 is located is used. In this case, since the position of the base station apparatus is determined in advance, the position information of the base station apparatus can be stored in advance in the positioning support system 10, and information specifying the cell where the communication terminal 60 is located is communicated. This is because when it is transmitted from the terminal 60, it can be transmitted to the communication terminal 60 based on the information.

  When the above base station apparatus is provided by the mobile communication network N1 (that is, the base station apparatus included in the mobile communication network N1), the position information of the base station apparatus can be easily obtained. Therefore, it is easy to store the position information as assist data in the positioning support system 10. However, when the communication terminal 60 is roaming out as in the present embodiment, the base station device 70 in which the communication terminal 60 is located is installed by another mobile communication network N2. It is difficult for the positioning support system 10 to grasp accurate information on the position where the station device 70 is provided. Therefore, when the approximate position information is created based on information provided from the communication terminal 60 (for example, information specifying a country in which the mobile terminal 60 is located or a communication carrier providing the mobile communication network N2), the accuracy is remarkably high. Therefore, the accuracy of the result of performing GPS positioning using this information may be lowered. In the following embodiment, the positioning system 1 including the positioning support system 10 in which the accuracy of the approximate position information transmitted to the communication terminal 60 is improved in view of the above problem will be described.

  Next, each device included in the positioning system 1 will be described. First, the SUPL server 20 constituting the positioning support system 10 included in the positioning system 1 is a device having the main functions of the positioning support system 10, stores assist data to be transmitted to the communication terminal 60, and On the basis of the request, the assist data is transmitted to the communication terminal 60.

  Similar to the SUPL server 20, the location information management device 30 that constitutes the positioning support system 10 has a function of performing an authentication process for performing communication related to positioning with the communication terminal 60, and also includes location information in the mobile communication network N1. It has a GMLC (Gateway Mobile Location Center) function for managing such data, and is realized, for example, as an EBSCP (External Business User Service Control Point). Specifically, profile data of a communication network (including mobile communication network N2) different from its own network (mobile communication network N1) is stored, and the data is transmitted to the SUPL server 20 as necessary. To do. Detailed processing according to the present embodiment will be described later.

  The user information management device 40 has a function of storing information (user profile) related to the owner (user) of a communication terminal that performs communication related to positioning with the positioning support system 10, and includes, for example, SUSCP (Specific User Service) Control Point). Then, the information is provided in response to a request from the location information management device 30.

  The GW apparatus 50 is provided between a mobile communication network (for example, the mobile communication network N2) different from the mobile communication network N1, and has a function of connecting the mobile communication network N2 and the mobile communication network N1. For example, it is realized as a Charging and Protocol Conversion Gateway (CPCG). In order for the communication terminal 60 roaming out like the communication terminal 60 to communicate with each device included in the mobile communication network N1, it is necessary to first connect to the GW device 50. The GW device 50 mediates communication between the communication terminal 60 that has transmitted a connection request from an external mobile communication network and each device (SUPL server 20 in the present embodiment) included in the mobile communication network N1. .

  The communication terminal 60 is used by a user. Specifically, for example, the communication terminal 60 is realized as a device having a communication function such as a mobile phone or a PDA (Personal Digital Assistance). In addition, the communication terminal 60 according to the present embodiment includes a function related to roaming that can perform communication using equipment (for example, the base station device 70) provided by another communication carrier, so that the mobile terminal It has a function of performing communication via the communication network N2. Further, the communication terminal 60 has a function of performing GPS positioning using assist data from the positioning support system 10.

  The base station device 70 is a device included in the mobile communication network N2, and forms a cell C1 by transmitting radio waves to a specific range. When the communication terminal 60 is in the cell C <b> 1, the communication terminal 60 can perform communication by transmitting and receiving information via the base station device 70. Each cell is given a unique cell ID, and this cell ID makes it possible to distinguish which base station device 70 is a related cell. A plurality of base station apparatuses including the base station apparatus 70 are managed by an SGSN (Serving GPRS Support Node) (not shown) that is located upstream of the base station apparatus in the mobile communication network N2 and controls packet communication. Has been.

  As shown in FIG. 2, the SUPL server 20, the location information management device 30, the user information management device 40, the GW device 50, and the base station device 70 included in the positioning system 1 are respectively a CPU 101 and a RAM that is a main storage device. (Random Access Memory) 102 and ROM (Read Only Memory) 103, a communication module 104 for performing communication, and a computer including hardware such as an auxiliary storage device 105 such as a hard disk. And the function of each apparatus is exhibited when these components operate. As shown in FIG. 3, the communication terminal 60 includes hardware such as a CPU (Central Processing Unit) 601, a RAM 602, a ROM 603, an operation unit 604, a wireless communication unit 605, a display 606, and an antenna 607. And the function of the communication terminal 60 is exhibited by these components operating.

  Note that, between the SUPL server 20 and the location information management device 30, between the location information management device 30 and the user information management device 40, between the user information management device 40 and the GW device 50, and between the GW device 50 and the SUPL server 20. Are connected via a wired network. Information is exchanged between the communication terminal 60 and the GW apparatus 50 and between the communication terminal 60 and the base station apparatus 70 by wireless communication.

  Returning to FIG. 1, the SUPL server 20 and the position information management device 30 included in the positioning support system 10 that is a positioning support device included in the positioning system 1 and that characterizes the present invention will be described in detail. The SUPL server 20 includes a communication unit (approximately position information transmitting unit, positioning result receiving unit) 21, a control unit (approximately position information transmitting unit, approximate position information updating unit) 22, an approximate position information DB (database) (approximately position). Information storage means) 23. The location information management device 30 includes a communication unit 31, a control unit (general location information transmission means) 32, and a management DB 33.

  The communication unit 21 of the SUPL server 20 functions as approximate position information transmitting means for transmitting assist data including approximate position information to the communication terminal 60 based on a positioning information transmission request transmitted from the communication terminal 60. Further, it also has a function as positioning result receiving means for receiving the positioning result transmitted from the communication terminal 60. Further, it further has a function of transmitting / receiving information to / from the location information management device 30. Information received by the communication unit 21 is sent to the control unit 22.

  The control unit 22 has a part of the function of the approximate position information transmitting unit that acquires approximate position information stored in the approximate position information DB 23 based on the positioning information transmission request transmitted from the communication terminal 60. Note that the approximate position information transmitted from the control unit 22 to the communication terminal 60 includes information transmitted from the position information management device 30 described later for the purpose of transmitting approximate position information with higher accuracy to the communication terminal 60. To be determined. The specific processing will be described in the description related to the positioning support method described later.

  In addition, the control unit 22 serves as an approximate position information update unit that updates approximate position information stored in an approximate position information DB 23 described later based on positioning result information indicating the result of GPS positioning transmitted from the communication terminal 60. It has a function. The update of the approximate position information by the control unit 22 is not limited to the rewriting of the approximate position information when the communication terminal 60 succeeds in GPS positioning, but when the approximate position information is determined to be defective because the GPS positioning has failed. Initialization of approximate position information is also included. The update of the approximate position information by the control unit 22 will be described later.

  The approximate position information DB 23 functions as approximate position information storage means for storing information on base stations related to the cell in association with the cell ID of the cell. FIG. 4 is an example of approximate position information stored in the approximate position information DB 23. Among the information shown in FIG. 4, MCC (Mobile Country Code), MNC (Mobile Network Code, operator code (for example, determined for each communication carrier)), and cell ID are predetermined. is there. The positioning information transmission request transmitted from the communication terminal 60 also includes the above MCC, MNC, and cell ID as information for specifying the cell where the communication terminal 60 is located. Also, Lat (Latitude (Y), latitude), Lon (Longitude (X), longitude), Alt (Altitude, altitude from the WGS84 ellipsoid used as a reference for GPS positioning), Unc (Uncertainty (k), latitude / longitude Unc-Alt (Uncertainty Altitude (k), altitude uncertainty) indicates the approximate position information stored corresponding to the cell ID. The uncertainty indicates the accuracy based on the calculation method of the approximate position information, the size (width) of the cell corresponding to the cell ID, the GPS positioning result using the approximate position information, and the like. Further, the necessity of update is a flag indicating whether or not the information stored in the table shown in FIG. 4 needs to be updated based on the positioning result transmitted from the communication terminal 60.

  As shown in FIG. 4, the approximate position information stored in association with the cell ID is either (1) information indicating the exact position of the base station apparatus related to the cell specified by the cell ID, or (2) the base station It is not information that accurately indicates the position of the device, but information that has been updated based on the results of positioning in the same cell in the past. Of these, the information indicating the exact location of the base station device (1) is inquired of the GMLC of the carrier managing the base station device by specifying the cell ID corresponding to the base station device, for example. Can be obtained. In this case, since accurate information is already stored in the approximate position information DB 23, it is not necessary to further update the information in the approximate position information DB 23, and a flag indicating “update unnecessary” is given to the information.

  However, as described above, since the number of communication carriers that provide information indicating the position of the base station apparatus is limited, it is difficult to grasp the accurate position of the base station apparatus in the approximate position information DB 23. Accordingly, the approximate position information DB 23 stores (2) approximate position information calculated based on the approximate position information and positioning results used in the past in the same cell. Thus, when the exact position of the base station apparatus is not known, new approximate position information is created based on the result of positioning in the cell specified by the cell ID by the control unit 22 (approximate position information update means). The information stored in the approximate position information DB 23 is updated. As a specific method, for example, when the communication terminal 60 performs positioning, it is specified by the approximate position information of the cell ID used by transmitting to the communication terminal 60 in response to a request from the communication terminal 60. And the midpoint of the position specified by the positioning result (in the same cell ID) by the communication terminal 60 and the latitude, longitude, and altitude are calculated, and the result is used as new approximate position information. And a method of calculating an average value of positioning results in the same cell ID in the past for each of latitude, longitude, and altitude, and using the result as new approximate position information. As described above, when the approximate position information is updated based on the positioning result by the communication terminal 60, a flag indicating “update required” is given to the approximate position information.

  In addition, as described above, when the position of the base station apparatus is not accurately known and positioning has not been performed in the cell having the same cell ID in the past, it is associated with the cell ID. The approximate position information is not stored in the approximate position information DB 23 in advance. In this case, position information obtained from the MCC and MNC transmitted from the communication terminal 60 is used as approximate position information transmitted to the communication terminal 60. This information is transmitted from the location information management device 30 described later, and the processing will be described later.

  FIG. 5 is a diagram illustrating an example of the approximate position information of the SGSN that is also stored in the approximate position information DB 23. As described above, the SGSN is a device that manages a plurality of base station devices, and the positioning information transmission request transmitted from the communication terminal 60 specifies the SGSN that manages the base station device 70 to which the communication terminal 60 is connected. Contains the IP (Internet Protocol) address of the SGSN. For this reason, although the position of the base station apparatus 70 is not known, when the SGSN position information is known, this information can also be used as the approximate position information. Since there are a plurality of base station devices under the management of the SGSN, it is necessary to cover a wider area than a cell managed by a single base station device. Therefore, the SGSN approximate position information may be set with higher uncertainty than the cell approximate position information. That is, the uncertainty of latitude / longitude and the uncertainty of altitude are appropriately changed according to the region in which approximate position information is estimated to be used. The information shown in FIG. 5 is stored when it is transmitted from a location information management device 30 described later for use in GPS positioning.

  Next, returning to FIG. 1, the position information management device 30 included in the positioning support system 10 will be described. The communication unit 31 of the location information management device 30 performs a communication process with the user information management device 40, thereby performing authentication processing of the communication terminal 60 that transmits a connection request to the SUPL server 20, and a SUPL server. A function of transmitting position information (position information specified by MCC and MNC, position information of SGSN, etc.) stored in the position information management apparatus 30 to the SUPL server 20 by performing communication with the position information management apparatus 30. Have.

  The control unit 32 has a function of performing authentication processing related to the communication terminal 60 based on a request from the SUPL server 20 and a part of the approximate position information transmitting unit that determines approximate position information to be transmitted to the communication terminal 60. It has the function of. The information included in the approximate location information transmission request transmitted from the communication terminal 60 and transmitted from the SUPL server 20 to the location information management device 30 includes the above-described MCC, MNC, and cell ID. It is included as information on roaming cells (roaming area information). Similarly, information (SGSN IP address) for specifying the SGSN that controls the base station apparatus 70 related to the cell where the communication terminal 60 is located is included. Based on these pieces of information, the control unit 32 can obtain (1) information for specifying the exact position of the base station apparatus 70, or (2) position of the SGSN that controls the base station apparatus 70. A determination is made as to whether the information management apparatus 30 holds the information. Based on this determination result, information related to the approximate position information determination transmitted from the control unit 32 to the SUPL server 20 is selected and transmitted to the SUPL server 20. Details of the above determination and processing based on the determination result will be described later.

  The management DB 33 functions as a part of approximate position information storage means for storing information related to determination of approximate position information to be transmitted to the communication terminal 60. An example of information stored in the management DB 33 is shown in FIG. The management DB 33 stores MCC, MNC, SGSN IP address, and location information (Lat, Lon, Alt, Unc, Unc-Alt) in association with each other. Also included are those in which the position information is stored in association with MCC and MNC. Of the information stored in the management DB 33 (information shown in FIG. 6), the location information stored in association with the IP address of the SGSN is based on, for example, information transmitted from an operator specified by the MCC and MNC. Is accurate and accurate information. In addition, when the SGSN location information is not disclosed, such as an operator (communication carrier) specified by the MNC “ZZZ”, location information (for example, the operator's (Location information indicating the location of the head office) is stored. As described above, the management DB 33 stores approximate position information obtained using at least a part of the IP addresses of the MCC, MNC, and SGSN.

Further, the information stored in the management DB 33 is provided with a flag indicating “whether or not inquiry to GMLC is possible” in association with MCC and MNC. This is a flag indicating whether the location information management device 30 can inquire the location information of the base station device corresponding to the cell ID to the GMLC of the operator. When a flag indicating “inquiry is possible” is given to the GMLC of a specific operator, the location information management device 30 inquires the location information of the base station device to the GMLC of the operator using the cell ID. , Accurate position information of the base station apparatus can be obtained. Whether or not it is possible to make an inquiry to GMLC is determined by, for example, exchanging a contract in advance between the communication carrier providing mobile communication network N1 and the operator of the other party. Information stored in the management DB 33 of the location information management device 30 is stored in advance by a communication provider that provides the mobile communication network N1. The control unit 32 of the location information management device 30 determines which information is to be transmitted to the SUPL server 20 based on the information stored in the management DB 33 described above, and appropriate information is determined based on the result. It is transmitted to the SUPL server 20.
In the positioning system 1 according to the present invention, each device functions as described above, so that approximate position information is transmitted to the communication terminal 60 in response to a request from the communication terminal 60, and a GPS positioning result by the communication terminal 60 is obtained. Based on the information, the approximate position information is updated.

<Positioning method by positioning system including positioning support system (positioning support method)>
Next, regarding the positioning method (positioning support method by the positioning support system 10) by the positioning system 1 including the above positioning support system 10, the sequence diagrams shown in FIGS. 7, 8, and 12, and FIGS. 9 to 11 and FIG. This will be described with reference to the flowchart shown in FIG. FIG. 7 is a sequence diagram for explaining processing for performing communication between the communication terminal 60 and the SUPL server 20. FIG. 8 is a sequence diagram for explaining the authentication process of the communication terminal 60 in the mobile communication network N1 and the process related to the preparation of the approximate position information to be transmitted to the communication terminal 60. FIG. 12 is a sequence diagram for explaining processing related to GPS positioning in the communication terminal 60 and processing after positioning. 9 to 11 are flowcharts illustrating details of the process shown in FIG. FIG. 13 is a flowchart for explaining details of the processing shown in FIG.

  First, a process for performing communication between the communication terminal 60 and the SUPL server 20 will be described with reference to FIG. When performing GPS positioning in the communication terminal 60, it is necessary to provide a communication path between the communication terminal 60 and the SUPL server 20 that transmits assist data for GPS positioning to the communication terminal 60. Therefore, the communication terminal 60 transmits a connection request for providing a communication path with the SUPL server 20 to the GW device 50 via the base station device 70. This connection request is transmitted when the user of the communication terminal 60 operates the communication terminal 60. The GW apparatus 50 receives this connection request, performs a TCP (Transmission Control Protocol) connection establishment process between the communication terminal 60 and the GW apparatus 50 (S01), and also between the GW apparatus 50 and the SUPL server 20. A TCP connection establishment process is performed (S02).

  In addition, when the TCP connection establishment process is performed between the GW device 50 and the communication terminal 60 (S01), information related to the communication terminal 60 transmitted from the communication terminal 60 is transmitted to the user information management device 40. The Here, the information transmitted to the user information management apparatus 40 includes the source IP address, source port number, SGSN IP address, and roaming location information of the communication terminal 60. These pieces of information are also transmitted to the SUPL server 20 when the above TCP connection is established. When receiving this information from the GW device 50, the user information management device 40 updates the user information stored in the user information management device 40 based on this information (S04). Thereby, the roaming location information (MCC, MNC and cell ID) related to the cell C1 where the communication terminal 60 is located and the information related to the IP address of the SGSN which controls the base station apparatus 70 related to the cell C1 are stored in the user information management. It is stored in the device 40.

  Subsequently, a process of establishing a TLS (Transport Layer Security) tunnel used for transmission / reception of information related to positioning is performed between the communication terminal 60 and the SUPL server 20 via the TCP connection created by the above process. (S05). With the above processing, a communication path for performing communication related to positioning between the communication terminal 60 and the SUPL server 20 is provided, and preparation for transmission / reception of information is completed.

  Next, an authentication process related to positioning in the communication terminal 60 will be described with reference to FIG. When a TLS tunnel is established by the above processing (S05), a positioning start request (ULP_SUPL-START) is transmitted from the communication terminal 60 to the SUPL server 20 (S11, approximate position information transmission step). Here, the positioning start request transmitted from the communication terminal 60 to the SUPL server 20 includes a session ID (an identifier commonly assigned for processing related to GPS positioning once) and communication indicating the positioning capability of the communication terminal 60. The terminal function (information indicating the communication terminal function), roaming location information, positioning accuracy by the communication terminal 60, and the connection status of the communication terminal 60 to the cell C1 are included. Further, as information for specifying the communication terminal 60, an MSISDN (Mobile Subscriber ISDN Number) of the communication terminal 60 is included. When receiving the positioning start request, the communication unit 21 of the SUPL server 20 requests the location information management device 30 for authentication processing related to the communication terminal 60 (HTTP_Authentication-Request) (S12). This request includes the session ID, roaming location information, the MSISDN of the communication terminal 60, the source IP address, and the source port number.

  Upon receiving this request from the SUPL server 20, the communication unit 31 of the location information management device 30 transmits the MSISDN of the communication terminal 60 to the user information management device 40 in order to confirm the user information. Is made (ISCP_Authentication-Request) (S13). When receiving the MSISDN of the communication terminal 60, the user information management device 40 calls the user information by reading the profile of the user (S14). Information relating to the user of the communication terminal 60 is transmitted from the GW apparatus 50 to the user information management apparatus 40 in advance and updated (S04). Therefore, the user information management device 40 acquires this information (source IP address, source port number, roaming location information, SGSN IP address) and transmits it to the location information management device 30 as a user information response (ISCP_Authentication-Response). (S15). In the position information management device 30, when the information transmitted from the user information management device 40 is received, the information is transmitted from the communication unit 31 to the control unit 32 together with the information transmitted from the SUPL server 20 first. And it is judged in the control part 32 whether communication with the communication terminal 60 and the SUPL server 20 may be continued by confirming whether both correspond (S16). Here, if the above information does not match, it is determined that the communication with the communication terminal 60 cannot be continued, and the connection is stopped. If it is determined that the process can be continued, the process proceeds to the process related to the approximate position information transmission.

  As processing related to determination of information to be transmitted to the communication terminal 60 as approximate position information, first, the control unit 32 determines information to be transmitted from the position information management device 30 to the SUPL server 20 (determination of transmission data). (S17, approximate position information transmission step), by transmitting the determined transmission data from the communication unit 31 to the SUPL server 20, the authentication process is completed and preparation for outputting the approximate position information is performed. (HTTP_Authentication-Response) is performed (S18, approximate position information transmission step). The instruction transmitted from the location information management device 30 to the SUPL server 20 includes a session ID, an authentication result, location information acquired by the location information management device 30 and the level of the location information (details will be described later). , Roaming location information, and SGSN IP address.

  Here, processing performed in the control unit 32 of the location information management device 30 will be described with reference to the flowchart shown in FIG. The control unit 32 uses the roaming area information and the information stored in the management DB 33 among the information transmitted from the communication terminal 60 via the SUPL server 20, and asks "Can other network operators be inquired?" Is determined (S101). This is determined based on whether or not the information stored in the management DB 33 includes a flag of “inquiry to GMLC is possible” for the operator specified by the MCC and MNC included in the roaming location information. Here, when it is determined that an inquiry to the GMLC is possible, the communication unit 31 of the location information management device 30 requests the operator's GMLC to provide location information using the cell ID (Lr-IF SRLIR). As a result, the location information of the base station device 70 specified by the cell ID is acquired (Lr-IF SRLIA) (S102). Then, it is determined that the position information of the base station device 70 obtained as a result is to be the transmission data, and is transmitted from the communication unit 31 to the SUPL server 20 (S103 (S18)). At this time, for transmission data transmitted from the communication unit 31 to the SUPL server 20, information indicating that the transmission data has been acquired by inquiring the GMLC of another network (mobile communication network N2). It is transmitted in correspondence.

  In addition, when transmitting the location information of the base station device 70 as transmission data from the location information management device 30 to the SUPL server 20, the information stored in the approximate location information DB 23 is associated with the information. And a flag indicating that “not to update the approximate position information DB 23 based on the positioning result transmitted from the communication terminal 60”. This is because the information of the base station device 70 acquired by making an inquiry to the GMLC is the most accurate, so this information is instructed to be used as the approximate position information with the highest priority, and the position information of the base station device 70 It is prohibited to use the result of positioning in the communication terminal 60 by using for updating the approximate position information stored in the approximate position information DB 23.

  On the other hand, when the flag indicating “inquiry to GMLC is not possible” is given, accurate position information of the base station device 70 corresponding to the cell ID cannot be acquired, so the base station device 70 is controlled next. It is confirmed whether the location information of the SGSN to be stored is stored in the management DB 33 (S105). Here, when the SGSN location information is stored in the management DB 33, it is determined that this location information is to be the transmission data described above, and is transmitted from the communication unit 31 to the SUPL server 20 (S106 ( S18)). At this time, the transmission data transmitted from the communication unit 31 to the SUPL server 20 is transmitted in association with information indicating that the transmission data is the SGSN position information stored in the management DB 33.

  If the SGSN location information is not stored in the management DB 33, it is determined that the location information derived from the MCC and MNC is the transmission data described above, and is transmitted from the communication unit 31 to the SUPL server 20. (S108 (S18)). At this time, for transmission data transmitted from the communication unit 31 to the SUPL server 20, information indicating that the transmission data is position information derived from the MCC and MNC stored in the management DB 33 corresponds to the transmission data. To be sent. As described above, the transmission data is transmitted from the position information management device 30 to the SUPL server 20, and the preparation of the approximate position information is instructed.

  On the other hand, when the communication unit 21 of the SUPL server 20 receives an instruction related to preparation of approximate position information together with transmission data, these pieces of information are sent to the control unit 22 to prepare approximate position information to be notified to the communication terminal 60. Is performed (S19, approximate position information transmission step).

  First, in the control unit 22, transmission data transmitted from the location information management device 30 includes (1) location information of the base station device 70, (2) location information of the SGSN, (3) information calculated by the MCC-MNC, It is confirmed from the information attached to the transmission data. Then, the control unit 22 performs processing according to this result.

  First, when the transmission data is (1) position information of the base station apparatus 70, the control unit 22 determines that the position information of the base station apparatus 70 is transmitted to the communication terminal 60 as approximate position information. . Then, the location information of the base station device 70 transmitted from the location information management device 30 is stored in the approximate location information DB 23 in association with the cell ID. At this time, for the information stored in the approximate position information DB 23, since the information is the most accurate information as approximate position information, a flag of “update unnecessary” is given.

  Next, when the transmission data is (2) SGSN position information, approximate position information to be notified to the communication terminal 60 is determined according to the flowchart shown in FIG. First, the control unit 22 determines whether the information stored in the approximate position information DB 23 is available (S201). For example, when the approximate position information DB 23 is disconnected from the network for some reason, the information stored in the approximate position information DB 23 cannot be used. In this way, it is determined whether or not the information stored in the approximate position information DB 23 in association with the cell ID can be used.

  Here, when it is determined that the information stored in the approximate position information DB 23 is available, the status of the communication terminal 60 is next checked (S202). The status of the communication terminal 60 confirmed here is information for confirming whether or not the communication terminal 60 is located in the area of the cell C1, and from the communication terminal 60 at the time of positioning start request (ULP_SUPL-START). This is information indicating the connection status for the notified cell C1. The case where the status is “Unknown” is a case where it is unknown whether or not the communication terminal 60 is continuously located in the cell C1 (possibility of not being located). Use of information stored in the position information DB 23 is suppressed. When this status is not “Unknown”, that is, when it is considered that the communication terminal 60 is continuously located in the cell C1, information corresponding to the cell ID is already stored. It is confirmed whether or not there is (S203).

  Here, for example, when the current GPS positioning by the communication terminal 60 is the first GPS positioning in the cell C1, the approximate position information associated with the cell ID of the cell C1 is still stored in the approximate position information DB23. Therefore, the information stored in the approximate position information DB 23 cannot be used. On the other hand, when the GPS positioning by the communication terminal has been performed in the cell C1 in the past, the approximate position information updated based on the GPS positioning result is stored in the approximate position information DB 23. It is determined to use the approximate position information stored in the position information DB 23 (S204). When it is determined that there is a problem in any of the above confirmations (that is, when it is determined that the information stored in the approximate position information DB 23 is not available), the status of the communication terminal 60 is “Unknown”. ”And when the information corresponding to the cell ID is not stored in the approximate position information DB 23), the SGSN position information transmitted from the position information management device 30 is used as the approximate position information. Is determined, and preparations thereof are advanced (S205).

  Next, when the transmission data is information calculated by (3) MCC-MNC, approximate position information to be notified to the communication terminal 60 is determined according to the flowchart shown in FIG. First, the control unit 22 determines whether the information stored in the approximate position information DB 23 is available (S301). Here, when it is determined that the information stored in the approximate position information DB 23 is available, the status of the communication terminal 60 is next confirmed (S302). If this status is not “Unknown”, that is, if it is considered that the communication terminal 60 is continuously located in the cell C1, then whether the information corresponding to the cell ID has already been stored. Confirmation is made (S303). Here, when the GPS positioning by the communication terminal has been performed in the cell C1 in the past, the approximate position information updated based on the GPS positioning result is stored in the approximate position information DB 23. It is determined to use the approximate position information stored in the DB 23 (S304). The above processing is performed in the same manner as (2) when the SGSN location information is transmitted from the location information management device 30.

  On the other hand, when it is determined that there is a problem in any of the above confirmations (that is, when it is determined that the information stored in the approximate position information DB 23 is unavailable), the status of the communication terminal 60 is “Unknown” ”And when the information corresponding to the cell ID is not stored in the approximate position information DB 23), it is confirmed whether the SGSN position information is stored in the approximate position information DB 23 ( S305). That is, the control unit 22 confirms whether or not the position information associated with the SGSN IP address transmitted from the communication terminal 60 is stored in the table shown in FIG. Here, when the location information of the SGSN is stored in the approximate location information DB 23, the location information is considered to be more accurate than the information calculated by the MCC-MNC. Is used, and preparations for notifying the communication terminal 60 are made (S306). However, when the SGSN location information is not stored in the approximate location information DB 23, it is determined that the information calculated by the MCC-MNC transmitted from the location information management device 30 is used as the approximate location information. Preparation for notifying is performed (S307).

  Through the above processing, the control unit 22 of the SUPL server 20 prepares the approximate position information to be transmitted to the communication terminal 60 (S19), and then performs positioning from the communication unit 21 to the communication terminal 60. A positioning start response (ULP_SUPL-RESPONSE) to the start request (S11) is transmitted (S20). The positioning start response at this time includes a session ID and information indicating the positioning method (“SET-Based-A-GPS” specifying the network assist method).

  Then, the process regarding the GPS positioning in the communication terminal 60 and the process after positioning are demonstrated using FIG. Based on the positioning method (network assist method) specified in the positioning start response (S20) from the SUPL server 20, the communication terminal 60 supplies a request for providing assist data (ULP_SUPL-POS-INT) including approximate position information to SUPL. It transmits to the server 20 (S21). This provision request includes session ID, roaming location information, and positioning performance (performance related to functions used in positioning by the network assist method) of the communication terminal 60.

  When the communication unit 21 of the SUPL server 20 receives the approximate position information provision request from the communication terminal 60, the communication unit 21 is notified to the control unit 22, and the approximate position information to be transmitted to the communication terminal 60 is transmitted by the control unit 22. Obtained (S22, approximate position information transmission step). Here, the process for transmitting the information to be transmitted to the communication terminal 60 determined in the above-described notification information output preparation (S19) to the communication terminal 60 (specifically, the information is converted into a SUPL_POS message). Storage process). Then, a response (ULP_SUPL-POS (RRLP_Measure-Position-Request)) including the GPS satellite route information and approximate position information acquired by a process different from the above process is transmitted to the communication terminal 60 ( S23, approximate position information transmission step). Here, as the session ID and assist data, approximate position information (latitude, longitude, altitude, latitude / longitude uncertainty, altitude uncertainty), and GPS satellite route information (ephemeris, almanac) It is transmitted to the communication terminal 60.

  Subsequently, in the communication terminal 60, GPS positioning is performed based on these pieces of information (S24), and the position of the communication terminal 60 is calculated by performing calculations in the communication terminal 60. Specifically, at the time of GPS positioning, the communication terminal 60 captures three or more GPS satellites using route information of GPS satellites transmitted from the SUPL server 20 as assist data, and from these satellites, The terminal is positioned using the transmitted signal and the approximate position information.

  Here, if the signals from three or more GPS satellites can be correctly received and the approximate position information is more accurate information, the GPS positioning is successful, and the latitude, longitude, altitude, and error radius of the communication terminal 60 are obtained. Can be obtained. Here, the error radius indicates whether the latitude, longitude, and altitude obtained as a result of the positioning calculation by the communication terminal 60 are accurate, and the uncertainty of the approximate position information transmitted from the SUPL server 20; Calculated based on the GPS signal reception accuracy and the like. However, if the number of GPS satellites that could receive the signal is small, or if the approximate position information is extremely inaccurate, GPS positioning may fail. As a case where the communication terminal 60 fails to capture three or more GPS satellites, for example, there is a case where positioning is performed indoors. In addition, when the approximate position information is extremely inaccurate, for example, it may not be included in the positioning result used for updating the approximate position information in the past (for example, obtained by malfunction or the like). ) When the positioning result is included, or when the approximate position information associated with the cell ID is not changed even though the cell ID of the cell is changed due to the change of accommodation. When the above problems occur, the GPS positioning by the communication terminal 60 may fail, and the communication terminal 60 may not be able to obtain information indicating the position of the terminal itself.

  After GPS positioning by the communication terminal 60, positioning result information (ULP_SUPL-POS (RRLP_Measure-Position-Response)) is transmitted from the communication terminal 60 to the SUPL server 20 and received by the communication unit 21 of the SUPL server 20. (S25, positioning result receiving step).

  At this time, the positioning result information transmitted from the communication terminal 60 to the SUPL server 20 includes a session ID and a positioning result (latitude, longitude, altitude, error radius) when the GPS positioning is successful in the communication terminal 60. And are included. In addition, when GPS positioning fails in the communication terminal 60, a session ID, an error code indicating the positioning failure, and satellite number information indicating the number of GPS satellites captured by the communication terminal 60 during GPS positioning are included. It is.

  Next, in the SUPL server 20, the approximate position information stored in the approximate position information DB 23 is updated by the control unit 22 based on the positioning result information transmitted from the communication terminal 60 (S26, approximate position information update step). ).

  A specific procedure for updating the approximate position information by the control unit 22 will be described with reference to FIG. First, the control unit 22 refers to the positioning result information transmitted from the communication terminal 60, and determines whether positioning is successful (S401). Whether the positioning is successful or not can be determined by whether the positioning result includes the positioning result or the error code. That is, these pieces of information become information (success / failure information) indicating the success or failure of GPS positioning in the communication terminal 60. If it is determined that the positioning is successful, the approximate position information stored in the approximate position information DB 23 is updated using the positioning result (S411). Specifically, when the approximate position information associated with the cell ID has not yet been stored in the approximate position information DB 23, the positioning result by the communication terminal 60 is newly stored as the approximate position information. Further, when the approximate position information stored in the approximate position information DB 23 is transmitted to the communication terminal 60, as described above, the approximate position information transmitted to the communication terminal 60 and the communication terminal 60 after positioning are used. The approximate position information is updated based on the transmitted result.

  Next, when it is determined that the positioning has failed, that is, when the error code is included in the positioning result information, the satellite number information included in the positioning result information is referred to and the satellite captured by the communication terminal 60 is acquired. It is determined whether the number is three or more (S402). Here, when the number of captured satellites is not three or more, that is, when the number of captured satellites is less than two, the communication terminal 60 can capture a sufficient number of GPS satellites for successful GPS positioning. Since it is conceivable that the GPS positioning has failed due to the absence, the update of the approximate position information is not performed, and the process related to the update of the approximate position information is terminated. On the other hand, when the number of captured satellites is three or more, the GPS positioning has failed even though the communication terminal 60 can capture a sufficient number of GPS satellites. 1 is added to the number of failures using this approximate position information (S403). The control unit 22 fails as a result of positioning using the same approximate position information, and holds the number of times that the control unit 22 regards it as defective for each approximate position information (that is, for each cell ID). . Then, as a result of adding 1 to the number of failures considered to be defective, it is determined whether the number of failures exceeds a predetermined threshold (for example, 5 times) (S404). The approximate position information is initialized (S405). If the number of failures is less than or equal to the threshold, the process is terminated without updating the approximate position information (S412). This threshold value is determined in advance by the administrator of the SUPL server 20 and held in the control unit 22. Note that the number of failures held by the control unit 22 is reset when the approximate position information is updated.

  As a method of initializing the approximate position information (S405), specifically, when approximate position information of the SGSN that manages the base station apparatus 70 corresponding to the cell ID is stored in the approximate position information DB 23, There is a method of inputting the approximate position information of the SGSN as new approximate position information (initial value) corresponding to the cell ID after deleting the approximate position information whose number of failures exceeds a threshold. Further, when the SGSN approximate position information is not held in advance, a method of inputting the position information specified by the MCC and the MNC as new approximate position information (initial value) corresponding to the cell ID can be used. . As another method, there is a method in which the approximate position information itself corresponding to the cell ID is deleted, and the approximate position information corresponding to the cell ID is not stored in the approximate position information DB 23. When the approximate position information is deleted from the approximate position information DB 23, the next time the communication terminal performs positioning in the cell specified by this cell ID, the same processing as when positioning is performed for the first time in the cell is performed. As a result, the approximate position information to be transmitted to the communication terminal is selected and transmitted.

  Thereafter, a notification (ULP_SUPL-END) indicating that a series of processing related to positioning has been completed is transmitted from the communication unit 21 of the SUPL server 20 to the communication terminal 60 (S27), thereby relating to the positioning by the communication terminal 60. Processing is terminated.

  If the communication terminal 60 fails in GPS positioning, after a series of processes related to GPS positioning described above, an assist data addition request is transmitted to the SUPL server 20, new assist data is received, and GPS positioning is performed again. Can also be done.

<Effects of positioning support system and positioning support method>
According to the positioning support system 10 according to the embodiment and the positioning method (positioning support method) by the positioning system 1 including the positioning support system 10, the SUPL server 20 receives the positioning result information transmitted from the communication terminal 60, Based on this positioning result information, the approximate position information stored in association with the cell ID is updated in the approximate position information DB 23. As described above, since the approximate position information stored in the approximate position information DB 23 is updated based on the results of positioning by the communication terminal in the same cell, the accuracy of the approximate position information can be improved. When the terminal 60 performs GPS positioning, approximate position information with higher accuracy can be transmitted to the communication terminal 60.

  In the positioning support system 1 described above, when the positioning calculation by the communication terminal 60 fails, the control unit 22 uses the error code included in the positioning result information transmitted from the communication terminal 60 and the satellite captured by the communication terminal 60. Based on the numerical information, it is determined whether the approximate position information transmitted to the communication terminal 60 is defective, and the approximate position information is initialized based on the result. Thus, by having the aspect which initializes the approximate position information determined to be defective, the accuracy of GPS positioning by the communication terminal 60 is reduced by continuing the positioning calculation using the approximate position information determined to be defective. Can be prevented. Further, by using the satellite number information to determine whether or not the approximate position information is defective, for example, when the positioning calculation fails due to insufficient capture of GPS satellites by the communication terminal 60, Initialization of the position information can be prevented, unnecessary initialization of the approximate position information can be suppressed, and approximate position information with higher accuracy can be provided.

  In the above embodiment, the new approximate position information is calculated based on the position specified by the approximate position information transmitted to the communication terminal 60 and the position specified by the positioning result information. The approximate position information stored in the information DB 23 can be updated to more appropriate and highly accurate information.

  Further, in the above embodiment, when the approximate position information is updated, information for specifying the position of the SGSN that is a base station management apparatus that manages a plurality of base stations including the base station 70 corresponding to the cell ID is newly added. By using it as location information, even when the approximate location information is initialized, the location of the cell where the communication terminal 60 is located and the approximate location information after initialization are prevented from being largely separated, A decrease in positioning accuracy can be prevented.

  In addition, when the approximate position information stored in the approximate position information DB 23 is accurate information obtained, for example, by making an inquiry to the GMLC of the mobile communication network N2, based on the positioning result by the communication terminal 60. The accuracy of the approximate position information is reduced by updating the approximate position information by storing the "flag indicating whether update is necessary" that can be flagged to be updated in association with the approximate position information. Can be prevented.

  As mentioned above, although preferred embodiment of this invention was described, the positioning system 1 containing the positioning assistance system 10 which concerns on this invention can perform a various change.

  For example, the functions related to the SUPL server 20 and the position information management device 30 included in the positioning support system 10 may be included in one device, or each function is distributed to different devices. It may be. In the above-described embodiment, the case where the communication terminal 60 acquires assist data from the SUPL server 20 to perform GPS positioning, and further performs the positioning calculation process for calculating the current position of the communication terminal 60 from the positioning data. About the positioning calculation process calculated to the present position of the communication terminal 60, it can also be set as the aspect performed with the apparatus different from the communication terminal 60. FIG.

  Moreover, although the said embodiment demonstrated using a cell as a communication area in which the client terminal 10 exists, the communication area which concerns on this invention is not limited to a cell. For example, even when the area managed by the SGSN that controls the packet communication and is located upstream of the base station device that manages the cell is regarded as the communication area, the positioning support similar to the above embodiment can be performed, and the SGSN The approximate position information can be updated in the same manner as in the above embodiment.

  In the above-described embodiment, a state is described in which the communication terminal 60 is roaming out from the mobile communication network N1, as in the case where the communication terminal 60 is used overseas, for example. However, the positioning support system 10 and the positioning support method according to the present invention can be applied even when the communication terminal 60 is not roaming out. That is, when the position information of the base station apparatus to which the communication terminal 60 is connected cannot be accurately grasped, the positioning support method according to the present embodiment can be suitably used.

  The update method for updating the approximate position information based on the positioning result information from the communication terminal 60 is the method described in the above embodiment (the position based on the approximate position information transmitted to the communication terminal 60 and the communication terminal. The method is not limited to a method in which the midpoint of the position based on the positioning result information from 60 is used as new approximate position information, or a method in which the average value of the results measured in the past in the same cell is used as new approximate position information). Various methods can be used. In that case, for example, a method of updating approximate position information by further utilizing the success rate of GPS positioning or the like can be used.

  In the above embodiment, the communication terminal 60 fails in GPS positioning, and the control unit 22 fails to determine whether to initialize the approximate position information based on the positioning result information from the communication terminal 60. A mode has been described in which the number of times is counted and initialization is performed when a predetermined threshold is exceeded. However, it is not essential to determine whether to perform initialization based on whether or not the threshold is exceeded. For example, when positioning result information including success / failure information (error code) indicating that GPS positioning has failed is received, it is confirmed whether or not the number of captured satellites is three or more (S404 in FIG. 13). As a result, when the number is three or more, the approximate position information may be initialized. In the above embodiment, it is confirmed whether or not the number of satellites to be captured is three or more, but this number is an example, and is not limited to three.

  Further, in the above-described embodiment, the aspect in which the satellite number information and the error code are transmitted to the SUPL server 20 only when the communication terminal 60 fails in GPS positioning has been described. However, the satellite number information may be transmitted to the SUPL server 20 even when the GPS positioning is successful in the communication terminal 60. That is, regardless of the success or failure of GPS positioning, the satellite number information can be included in the positioning result information and transmitted.

  Moreover, although the said embodiment demonstrated the aspect which updates approximate position information when the frequency | count (failure frequency) considered to be defect in the control part 22 exceeded the predetermined threshold value, rough position information was demonstrated. Is not limited to the above embodiment. For example, the ratio (failure rate) of the number of failures to the number of measurements using specific approximate position information may be used as a threshold for whether or not the approximate position information needs to be updated.

  Moreover, although the said embodiment demonstrated the aspect which updates the approximate position information stored in approximate position information DB23 based on the positioning result information from the communication terminal 60 which transmitted approximate position information, approximate position information is not necessarily changed. Only the positioning result of the transmitted communication terminal is not used for updating the approximate position information, and is stored in the approximate position information DB 23 based on the positioning result information obtained by positioning without transmitting the approximate position information (for example, by an independent method). Updated information may be updated.

  Moreover, in the said embodiment, although the communication terminal 60 has demonstrated the aspect which performs GPS positioning using the assist data transmitted from the SUPL server 20, when GPS positioning using assist data is not successful, It is also possible to stop using the assist data at the communication terminal 60 or continue the GPS positioning using the assist data uniquely generated at the communication terminal 60. In this case, when the positioning result information is notified from the communication terminal 60 to the SUPL server 20, it is possible to further notify the approximate position information by notifying which assist data is used to perform the GPS positioning. High accuracy can be achieved.

DESCRIPTION OF SYMBOLS 1 ... Positioning system, 10 ... Positioning support system, 20 ... SUPL server, 30 ... Location information management apparatus, 40 ... User information management apparatus, 50 ... GW apparatus, 60 ... Communication terminal, 70 ... Base station apparatus.

Claims (7)

Used for positioning calculation in a communication terminal that captures a satellite and performs positioning using information from the satellite, approximate position information indicating the position of the communication area in which the communication terminal is located, and information for identifying the communication area Approximate position information storage means for storing
Based on the positioning information transmission request transmitted from the communication terminal including information specifying the communication area where the communication terminal is located, the approximate position is associated with information specifying the communication area where the communication terminal is located. An approximate position information transmitting means for acquiring the approximate position information stored in the information storage means and transmitting the approximate position information to the communication terminal;
Positioning result receiving means for receiving positioning result information which is information transmitted from the communication terminal which has acquired the approximate position information transmitted by the approximate position information transmitting means and which indicates a result of the positioning calculation;
An approximate position information updating means for updating the approximate position information stored in the approximate position information storage means based on the positioning result information, and
The positioning result information includes success / failure information indicating whether the positioning calculation has succeeded or failed, and satellite number information indicating the number of satellites captured by the communication terminal in the positioning calculation,
The approximate position information update means determines whether the approximate position information is defective based on the success / failure information and the satellite number information, and based on the result, the approximate position stored in the approximate position information storage means The positioning support apparatus characterized by initializing the approximate position information transmitted to the communication terminal among the information. The approximate position information update means includes:
The success / failure information is information indicating that the positioning calculation has failed, and it is determined whether the number of satellites specified by the satellite number information is greater than a predetermined value, and the success / failure information has failed the positioning calculation. When the number of satellites is greater than a predetermined value and information indicating that the approximate position information transmitted to the communication terminal is determined to be defective,
Initializing the approximate position information transmitted to the communication terminal among the approximate position information stored in the approximate position information storage means when the number of times determined to be defective exceeds a threshold value. The positioning support apparatus according to claim 1, characterized in that: The approximate position information is information for specifying a position of a base station related to the communication area,
The positioning support device according to claim 1, wherein the approximate position information and the positioning result information are information including latitude and longitude.   The approximate position information update means uses, as the new approximate position information, information specifying the position of a base station management apparatus that manages a plurality of base stations including the base station at the time of initialization. The positioning support device according to claim 3. The approximate position information update means calculates new approximate position information based on the position specified by the approximate position information transmitted to the communication terminal and the position specified by the positioning result information. The positioning support apparatus according to any one of claims 1 to 4. The approximate position information storage means stores a flag indicating whether or not the approximate position information needs to be updated in association with the approximate position information,
6. The approximate position information update unit updates the approximate position information when it is determined that the update of the approximate position information is necessary based on the flag. The positioning support device according to any one of the above. Used for positioning calculation in a communication terminal that captures a satellite and performs positioning using information from the satellite, approximate position information indicating the position of the communication area in which the communication terminal is located, and information for identifying the communication area A positioning support method by a positioning support device comprising approximate position information storage means for storing the information in association with each other,
Information for specifying the communication area in which the communication terminal is located based on a positioning information transmission request transmitted from the communication terminal, including information for specifying the communication area in which the communication terminal is located by the approximate position information transmission means An approximate position information transmitting step for acquiring the approximate position information stored in the approximate position information storage means in association with and transmitting the approximate position information to the communication terminal;
The communication terminal that has acquired the approximate position information transmitted by the approximate position information transmitting means receives positioning result information that is information indicating a result of the positioning calculation transmitted from the communication terminal by performing a positioning calculation. Positioning result receiving step;
An approximate position information update means for updating the approximate position information stored in the approximate position information storage means based on the positioning result information by an approximate position information update means,
The positioning result information includes success / failure information indicating whether the positioning calculation has succeeded or failed, and satellite number information indicating the number of satellites captured by the communication terminal in the positioning calculation,
In the approximate position information update step, it is determined whether the approximate position information is defective based on the success / failure information and the satellite number information, and based on the result, the approximate position stored in the approximate position information storage means The positioning support method characterized by initializing the approximate position information transmitted to the communication terminal in the information.

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