Position estimation system

• US 8,121,621 B2
• Filed: 06/27/2008
• Issued: 02/21/2012
• Est. Priority Date: 06/27/2007
• Status: Expired due to Fees

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Ogata, Susumu, Kimoto, Masatoshi, Hoshino, Jin
• Primary Examiner(s): Patel, Nimesh
• Application Number:
  US12/163,386
• Publication Number:
  US 20090005083A1
• Time in Patent Office: 1,334 Days
• Field of Search: 455/456.2, 455/456.5, 455/457, 342/357.49, 342/357.2, 342/357.78
• US Class Current: 455/456.2
• CPC Class Codes: G01S 5/0236 Assistance data, e.g. base station almanac
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location

Abstract

A position of a mobile communication terminal in an environment where the terminal cannot communicate with a GPS is defined more narrowly than a sector area of a base station in which the mobile communication terminal is located so that the position of the mobile communication terminal can be estimated more accurately. Even if a mobile communication terminal is in an environment where the terminal cannot communicate with a GPS, the latitude and longitude of the center of a sector of the wireless base station in which the mobile communication terminal is located is obtained according to a predetermined calculation by a base station database device, and the obtained latitude and longitude is sent back as an estimated latitude and longitude of the mobile communication terminal to the mobile communication terminal via the wireless base station.

Claims

1. A position estimation system comprising:

a mobile communication terminal;

a base station which wirelessly communicates with the mobile communication terminal and which holds its own base station ID that is unique information; and

a database device which holds an information table having base station information including a latitude, a longitude, a tilt angle, an antenna aperture angle, antenna directivity, and an antenna height of the base station which are associated with the base station ID,

wherein the position estimation system estimates a position of the mobile communication terminal located in a radio area of the base station by using the database device, even in an environment where the mobile communication terminal cannot communicate with a Global Positioning System,

wherein the base station comprises;

an ID transmission section for sending the base station ID to the database device when the mobile communication terminal requests acquisition of the position; and

a relay section for relaying information of an estimated latitude and longitude of the mobile communication terminal which is sent from the database device to the mobile communication terminal requesting the acquisition of the position,

wherein the database device comprises;

a calculating section for performing processing for reading the base station information associated with the base station ID from the information table when the base station ID is received, obtaining a latitude and a longitude of the center of a sector that is the centroid of gravity of the sector in the radio area of the base station according to a predetermined calculation using the base station information, and determining the obtained latitude and longitude as the estimated latitude and longitude of the mobile communication terminal; and

a position transmission section for sending the information of the estimated latitude and longitude of the mobile communication terminal obtained by the calculating section to the relevant base station,

wherein, for obtaining the latitude and the longitude of the center of the sector, the calculating section comprises;

a first calculating section for obtaining a cell radius of the radio area of the base station by use of information of the tilt angle and the antenna height from the base station information;

a second calculating section for obtaining a distance between the base station and the center of the sector by use of information of the cell radius obtained by the first calculating section, the antenna directivity, and the antenna aperture angle, and position coordinates of the center of the sector; and

a third calculating section for converting the position coordinates of the center of the sector obtained by the second calculating section into a latitude and a longitude, so that the calculating section obtains latitude and longitude of the center of the sector by use of the latitude and longitude converted by the third calculating section and information on a latitude and a longitude of the base station, and outputs the latitude and longitude of the center of the sector as the estimated latitude and longitude, and

wherein the mobile communication terminal identifies the relayed information of the estimated latitude and longitude of the mobile communication terminal as position information of the latitude and the longitude of the mobile communication terminal.

13. The position estimation system according to any one of claims 1 to 7,

wherein the database device further comprises a map database section for storing map information in which an exceptional location is defined, and

wherein, after obtaining the estimated latitude and longitude of the mobile communication terminal, the calculating section performs processing for deleting information of the estimated latitude and longitude if the estimated latitude and longitude corresponds to the exceptional location in the map information of the map database section.

2. A position estimation system comprising:

a position request terminal which specifies a terminal ID of any mobile communication terminal and which requests acquisition of a position of the relevant mobile communication terminal;

a mobile communication terminal which holds its own terminal ID that is unique information;

a base station which wirelessly communicates with the mobile communication terminal as well as communicates with the position request terminal via a relay server, and which holds its own base station ID that is unique information; and

a database device which holds an information table having base station information including a latitude, a longitude, a tilt angle, an antenna aperture angle, an antenna directivity, and an antenna height of the base station which are associated with the base station ID,

the position estimation system estimating the position of the mobile communication terminal located in a radio area of the base station by the database device when the acquisition of the position is requested, even in an environment where the mobile communication terminal cannot communicate with a Global Positioning System,

wherein the base station comprises;

a request transmission section for, when position acquisition request information including the terminal ID at a time when the acquisition of the position is requested is received, sending the information to the mobile communication terminal;

an ID transmission section for sending the base station ID to the database device when a response signal is received from the mobile communication terminal in response to the request for the acquisition of the position sent by the request transmission section; and

a relay section for relaying information of an estimated latitude and longitude of the mobile communication terminal which is sent from the database device to the request terminal requesting the acquisition of the position,

wherein the mobile communication terminal comprises an acknowledgement section for sending back the response signal to the base station which has sent the request for the acquisition of the position if the terminal ID included in the position acquisition request information received from the base station is identical to the terminal ID held by the mobile communication terminal,

wherein the database device comprises;

a calculating section for performing processing for reading the base station information associated with the base station ID from the information table when the base station ID is received, obtaining a latitude, a longitude of the center of a sector that is the centroid of gravity of the sector in the radio area of the base station according to a predetermined calculation using the base station information, and determining the obtained latitude and longitude as the estimated latitude and longitude of the mobile communication terminal; and

a position transmission section for sending the information of the estimated latitude and longitude of the mobile communication terminal obtained by the calculating section to the base station,

wherein, for obtaining the latitude and the longitude of the center of the sector, the calculating section comprises;

a first calculating section for obtaining a cell radius of the radio area of the base station by use of information of the tilt angle and the antenna height from the base station information;

a second calculating section for obtaining a distance between the base station and the center of the sector by use of information of the cell radius obtained by the first calculating section, the antenna directivity, and the antenna aperture angle, and position coordinates of the center of the sector; and

a third calculating section for converting the position coordinates of the center of the sector obtained by the second calculating section into a latitude and a longitude, so that the calculating section obtains latitude and longitude of the center of the sector by use of the latitude and longitude converted by the third calculating section and information on a latitude and a longitude of the base station, and outputs the latitude and longitude of the center of the sector as the estimated latitude and longitude, and

wherein the request terminal identifies the relayed information of the estimated latitude and longitude of the mobile communication terminal as position information of the latitude and the longitude of the mobile communication terminal whose position is requested to be acquired.

3. A position estimation system comprising:

a mobile communication terminal which holds its own terminal ID that is unique information;

a base station which wirelessly communicates with the mobile communication terminal as well as communicates with a position acquisition terminal via a relay server, and which holds its own base station ID that is unique information; and

a database device which holds an information table having base station information including a latitude, a longitude, a tilt angle, an antenna aperture angle, an antenna directivity, and an antenna height of the base station which are associated with the base station ID,

the position estimation system estimating a position of the mobile communication terminal by using the database device when the mobile communication terminal notifies the position acquisition terminal of the position of the mobile communication terminal, even in an environment where the mobile communication terminal cannot communicate with a Global Positioning System,

wherein the mobile communication terminal comprises;

a position notification section for notifying the position acquisition terminal of the position of the mobile communication terminal using position notification information including a position acquisition terminal ID that is unique information of the position acquisition terminal and the terminal ID of the mobile communication terminal,

wherein the base station comprises;

an ID transmission section for sending the base station ID to the database device when the position notification request information is received; and

a relay section for adding the position acquisition terminal ID and the terminal ID of the terminal requesting the position notification request to estimated latitude and longitude information of the mobile communication terminal sent from the database device and sending the estimated latitude and longitude information to the relay server,

wherein the relay server comprises a recognition transmission section for recognizing the position acquisition terminal ID included in the estimated latitude and longitude information from the base station and sending the estimated latitude and longitude information to the position acquisition terminal having the recognized ID,

wherein the database device comprises;

a calculating section for performing processing for reading the base station information associated with the base station ID from the information table when the base station ID is received, obtaining a latitude, a longitude of a center of the sector that is the centroid of gravity of the sector in a radio area of the base station according to a predetermined calculation using the base station information, and determining the obtained latitude and longitude as the estimated latitude and longitude of the mobile communication terminal; and

a position transmission section for sending the information of the estimated latitude and longitude of the mobile communication terminal obtained by the calculating section to the base station,

wherein, for obtaining the latitude and the longitude of the center of the sector, the calculating section comprises;

a first calculating section for obtaining a cell radius of the radio area of the base station by use of information of the tilt angle and the antenna height from the base station information;

a second calculating section for obtaining a distance between the base station and the center of the sector by use of information of the cell radius obtained by the first calculating section, the antenna directivity, and the antenna aperture angle, and position coordinates of the center of the sector; and

a third calculating section for converting the position coordinates of the center of the sector obtained by the second calculating section into a latitude and a longitude, so that the calculating section obtains latitude and longitude of the center of the sector by use of the latitude and longitude converted by the third calculating section and information on a latitude and a longitude of the base station, and outputs the latitude and longitude of the center of the sector as the estimated latitude and longitude, and

wherein the position acquisition terminal identifies the estimated latitude and longitude information sent form the relay server as position information of the latitude and the longitude of the mobile communication terminal having the terminal ID of the terminal requesting the position notification request that is included in the estimated latitude and longitude information.

4. A position estimation system comprising:

a base station which holds its own base station ID that is unique information;

a mobile communication terminal which stores acquired base station IDs that are IDs of a plurality of base stations acquirable through wireless communication; and

a database device which holds an information table having base station information including a latitude, a longitude, a tilt angle, an antenna aperture angle, an antenna directivity, and an antenna height of each base station which are associated with each respective base station ID,

the position estimation system estimating a position of the mobile communication terminal located in a radio area of the base station by the database device, even in an environment where the mobile communication terminal cannot communicate with a Global Positioning System,

wherein the mobile communication terminal comprises an acquired ID transmission section for, in response to a request for acquisition of the acquired base station IDs sent from the base station in response to a request for acquisition of a position of the mobile communication terminal, sending the plurality of acquired base station IDs held by the mobile communication terminal to the base station requesting the acquisition of the acquired base station IDs,

wherein the base station comprises;

an acquired ID requesting section for requesting acquisition of the acquired base station IDs when the mobile communication terminal requests the acquisition of the position;

an ID sending/receiving section for receiving the plurality of acquired base station IDs sent in response to the request for the acquisition request and sending the acquired base station IDs to the database device; and

a relay section for relaying information of an estimated latitude and longitude of the mobile communication terminal which is sent from the database device to the mobile communication terminal requesting the acquisition of the position,

wherein the database device comprises;

a calculating section for performing processing for reading the base station information associated with each of the acquired base station IDs from the information table when the plurality of acquired base station IDs are received, obtaining a latitude, a longitude of the center of a sector that is the centroid of gravity of the sector in the radio area for each of the base stations having the respective acquired base station IDs according to a predetermined calculation using the base station information, and determining an average of the obtained latitudes and longitudes as the estimated latitude and longitude of the mobile communication terminal; and

a position transmission section for sending the information of the estimated latitude and longitude of the mobile communication terminal obtained by the calculating section to the relevant base station,

wherein, for obtaining the latitude and the longitude of the center of the sector, the calculating section comprises;

a first calculating section for obtaining a cell radius of the radio area of the base station by use of information of the tilt angle and the antenna height from the base station information;

a second calculating section for obtaining a distance between the base station and the center of the sector by use of information of the cell radius obtained by the first calculating section, the antenna directivity, and the antenna aperture angle, and position coordinates of the center of the sector; and

a third calculating section for converting the position coordinates of the center of the sector obtained by the second calculating section into a latitude and a longitude, so that the calculating section obtains latitude and longitude of the center of the sector by use of the latitude and longitude converted by the third calculating section and information on a latitude and a longitude of the base station, and outputs the latitude and longitude of the center of the sector as the estimated latitude and longitude, and

wherein the mobile communication terminal identifies the relayed information of the estimated latitude and longitude of the mobile communication terminal as position information of a latitude and a longitude of the mobile communication terminal.

8. The position estimation system according to any one of claims 4 to 7, wherein each base station ID of the information table is associated with a priority level, and the calculating section performs processing for obtaining the latitude and longitude of the center of the sector for each of the base stations and then determining the latitude and longitude of the center of the sector of the base station having a base station ID which is higher in the priority level as the estimated latitude and longitude of the mobile communication terminal.

9. The position estimation system according to any one of claims 4 to 7, wherein each base station ID of the information table is associated with an exception flag which represents a wireless base station in a narrow area where a plurality of wireless base stations are installed, and the calculating section is not allowed to perform calculation to obtain the latitude and the longitude of the center of the sector of the base station having the base station ID that is associated with the exception flag.

10. The position estimation system according to any one of claims 4 to 7, wherein the calculating section is not allowed to perform calculation to obtain the latitude and the longitude of the center of the sector of the base station having a base station ID associated with the tilt angle if the tilt angle is zero degrees.

11. The position estimation system according to claim 9, wherein the calculating section obtains the latitude and longitude of the center of the sector of the base station having the base station ID that is not associated with the exception flag, and when the obtained latitude and longitude is determined as the estimated latitude and longitude of the mobile communication terminal, adds an error on a random basis to the estimated latitude and longitude.

12. The position estimation system according to claim 10, wherein the calculating section obtains the latitude and longitude of the center of the sector of the base station having the base station ID that is not associated with the tilt angle, when the tilt angle is zero degrees, and when the obtained latitude and longitude is determined as the estimated latitude and longitude of the mobile communication terminal, adds an error on a random basis to the estimated latitude and longitude.

14. The position estimation system according to any one of claims 4 to 7,

wherein the second calculating section reads the latitudes and the longitudes of the respective base stations in the base station information associated with the respective acquired base station IDs from the information table when the plurality of acquired base station IDs are received, and determining an average of the latitudes and longitudes of the base stations as the estimated latitude and longitude of the mobile communication terminal, and

wherein the position transmission section sends information of the estimated latitude and longitude of the mobile communication terminal obtained by the second calculating section to the relevant base station.

15. The position estimation system according to claim 14,

wherein the database device further comprises a map database section for storing map information in which an exceptional location is defined, and

wherein, after obtaining the estimated latitude and longitude of the mobile communication terminal, the second calculating section performs processing for deleting information of the estimated latitude and longitude if the estimated latitude and longitude corresponds to the exceptional location in the map information of the map database section.

5. A position estimation system comprising:

a position request terminal which specifies a terminal ID of any mobile communication terminal and requests acquisition of a position of the relevant mobile communication terminal;

a base station which communicates with the position request terminal via a relay server and holds its own base station ID that is unique information;

a mobile communication terminal which stores acquired base station IDs that are IDs of a plurality of base station acquirable through wireless communication; and

a database device which holds an information table having base station information including a latitude, a longitude, a tilt angle, an antenna aperture angle, an antenna directivity, and an antenna height of each base station which are associated with each respective base station ID,

the position estimation system estimating the position of the mobile communication terminal located in a radio area of the base station by the database device when the acquisition of the position is requested, even in an environment where the mobile communication terminal cannot communicate with a Global Positioning System,

wherein the base station comprises;

a request transmission section for, when position acquisition request information including the terminal ID at a time when the acquisition of the position is requested is received, sending the information to the mobile communication terminal;

an ID sending/receiving section for receiving the plurality of acquired base station IDs from the mobile communication terminal in response to the request for the acquisition of the position sent by the request transmission section and sending the plurality of acquired base station IDs to the database device; and

a relay section for relaying information of an estimated latitude and longitude of the mobile communication terminal which is sent from the database device to the request terminal requesting the acquisition of the position,

wherein the mobile communication terminal comprises a check/transmission section for sending the plurality of acquired base station IDs held by the mobile communication terminal to the base station which has sent the position acquisition request information if the terminal ID included in the position acquisition request information received from the base station is identical to the terminal ID held by the mobile communication terminal,

wherein the database device comprises;

a calculating section for performing processing for reading the base station information associated with each of the acquired base station IDs from the information table when the plurality of acquired base station IDs are received, obtaining a latitude and a longitude of the center of a sector that is the centroid of gravity of the sector in the radio area for each of the base stations having the respective acquired base station IDs according to a predetermined calculation using the base station information, and determining an average of the obtained latitudes and longitudes as the estimated latitude and longitude of the mobile communication terminal; and

a position transmission section for sending the information of the estimated latitude and longitude of the mobile communication terminal obtained by the calculating section to the relevant base station,

wherein, for obtaining the latitude and the longitude of the center of the sector, the calculating section comprises;

a first calculating section for obtaining a cell radius of the radio area of the base station by use of information of the tilt angle and the antenna height from the base station information;

a second calculating section for obtaining a distance between the base station and the center of the sector by use of information of the cell radius obtained by the first calculating section, the antenna directivity, and the antenna aperture angle, and position coordinates of the center of the sector; and

a third calculating section for converting the position coordinates of the center of the sector obtained by the second calculating section into a latitude and a longitude, so that the calculating section obtains latitude and longitude of the center of the sector by use of the latitude and longitude converted by the third calculating section and information on a latitude and a longitude of the base station, and outputs the latitude and longitude of the center of the sector as the estimated latitude and longitude, and

wherein the request terminal identifies the relayed information of the estimated latitude and longitude of the mobile communication terminal as position information of a latitude and a longitude of the mobile communication terminal whose position is requested to be acquired.

6. A position estimation system comprising:

a mobile communication terminal which stores its own terminal ID which is unique information and acquired base station IDs which are IDs of a plurality of base stations acquirable through wireless communication;

a base station which wirelessly communicates with the mobile communication terminal as well as communicates with a position acquisition terminal via a relay server; and

a database device which holds an information table having base station information including a latitude, a longitude, a tilt angle, an antenna aperture angle, an antenna directivity, and an antenna height of each base station which are associated with each respective base station ID,

the position estimation system estimating a position of the mobile communication terminal by the database device when the mobile communication terminal notifies the position acquisition terminal of the position of the mobile communication terminal, even in an environment where the mobile communication terminal cannot communicate with a Global Positioning System,

wherein the mobile communication terminal comprises a position notification section for notifying the position acquisition terminal of the position of the mobile communication terminal using position notification information including a position acquisition terminal ID that is unique information of the position acquisition terminal, the acquired base station IDs, and the terminal ID of the mobile communication terminal,

wherein the base station comprises a request receiving section for receiving the position notification request information and obtains the acquired base station IDs, the position acquisition terminal ID, and the terminal ID in the information;

an ID sending/receiving section for sending the acquired base station IDs obtained by the request receiving section to the database device; and

a relay section for adding the position acquisition terminal ID and terminal ID obtained by the request receiving section to estimated latitude and longitude information of the mobile communication terminal sent from the database device and sending the estimated latitude and longitude information to the relay server,

wherein the relay server comprises a recognition transmission section for recognizing the position acquisition terminal ID included in the estimated latitude and longitude information from the base station and sending the estimated latitude and longitude information to the position acquisition terminal having the recognized ID,

wherein the database device comprises;

a calculating section for performing processing for reading the base station information associated with each of the acquired base station IDs from the information table when the plurality of acquired base station IDs are received, obtaining a latitude, a longitude of a center of the sector that is the centroid of gravity of the sector in the radio area for each of the base stations having the respective acquired base station IDs according to a predetermined calculation using the base station information, and determining an average of the obtained latitudes and longitudes as the estimated latitude and longitude of the mobile communication terminal; and

a position transmission section for sending the information of the estimated latitude and longitude of the mobile communication terminal obtained by the calculating section to the relevant base station,

wherein, for obtaining the latitude and the longitude of the center of the sector, the calculating section comprises;

a first calculating section for obtaining a cell radius of the radio area of the base station by use of information of the tilt angle and the antenna height from the base station information;

a second calculating section for obtaining a distance between the base station and the center of the sector by use of information of the cell radius obtained by the first calculating section, the antenna directivity, and the antenna aperture angle, and position coordinates of the center of the sector; and

a third calculating section for converting the position coordinates of the center of the sector obtained by the second calculating section into a latitude and a longitude, so that the calculating section obtains latitude and longitude of the center of the sector by use of the latitude and longitude converted by the third calculating section and information on a latitude and a longitude of the base station, and outputs the latitude and longitude of the center of the sector as the estimated latitude and longitude, and

wherein the position acquisition terminal identifies the estimated latitude and longitude information sent form the relay server as position information of a latitude and a longitude of the mobile communication terminal having the terminal ID of the terminal requesting the position notification request that is included in the estimated latitude and longitude information.

7. A position estimation system comprising:

a position request terminal which specifies a terminal ID of any mobile communication terminal and requests acquisition of a position of the relevant mobile communication terminal;

a base station which communicates with the position request terminal via a relay server and holds its own base station ID that is unique information;

a mobile communication terminal which stores acquired base station IDs that are IDs of a plurality of base stations acquirable through wireless communication; and

a database device which holds an information table having base station information including a latitude, a longitude, a tilt angle, an antenna aperture angle, an antenna directivity, and an antenna height of each base station which are associated with each respective base station ID,

the position estimation system estimating the position of the mobile communication terminal located in a radio area of the base station by the database device when the acquisition of the position is requested, even in an environment where the mobile communication terminal cannot communicate with a Global Positioning System,

wherein the mobile communication terminal comprises an acquired ID transmission section for sending its own terminal ID associated with the acquired base station IDs to the relevant base station when the mobile communication terminal is located in the radio area of the base station,

wherein the base station comprises;

an acquired ID receiving section for receiving the acquired base station IDs paired with the terminal ID from the mobile communication terminal;

a terminal ID information storage section for storing the received acquired base station IDs paired with the terminal ID;

a location checking/ID transmission section for, when position acquisition request information including the terminal ID at a time when the acquisition of the position is requested is received, if the mobile communication terminal having the relevant terminal ID is located in the area of the base station, sending the acquired base station IDs paired with the relevant terminal ID stored by the terminal ID information storage section to the database device; and

a relay section for relaying information of an estimated latitude and longitude of the mobile communication terminal which is sent from the database device to the request terminal requesting the acquisition of the position,

wherein the database device comprises;

a calculating section for performing processing for reading the base station information associated with each of the acquired base station IDs from the information table when the plurality of acquired base station IDs are received, obtaining a latitude, a longitude of the center of a sector that is the centroid of gravity of the sector in the radio area for each of the base stations having the respective acquired base station IDs according to a predetermined calculation using the base station information, and determining an average of the obtained latitudes and longitudes as the estimated latitude and longitude of the mobile communication terminal; and

a position transmission section for sending the information of the estimated latitude and longitude of the mobile communication terminal obtained by the calculating section to the relevant base station,

wherein, for obtaining the latitude and the longitude of the center of the sector, the calculating section comprises;

a first calculating section for obtaining a cell radius of the radio area of the base station by use of information of the tilt angle and the antenna height from the base station information;

a second calculating section for obtaining a distance between the base station and the center of the sector by use of information of the cell radius obtained by the first calculating section, the antenna directivity, and the antenna aperture angle, and position coordinates of the center of the sector; and

a third calculating section for converting the position coordinates of the center of the sector obtained by the second calculating section into a latitude and a longitude, so that the calculating section obtains latitude and longitude of the center of the sector by use of the latitude and longitude converted by the third calculating section and information on a latitude and a longitude of the base station, and outputs the latitude and longitude of the center of the sector as the estimated latitude and longitude, and

wherein the request terminal identifies the relayed information of the estimated latitude and longitude of the mobile communication terminal as position information of the latitude and longitude of the mobile communication terminal whose position is requested to be acquired.