Location estimating apparatus and location estimating method

• US 7,593,739 B2
• Filed: 04/27/2006
• Issued: 09/22/2009
• Est. Priority Date: 04/28/2005
• 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: Oguri, Shin, Kimoto, Masatoshi
• Primary Examiner(s): Feild, Joseph H
• Assistant Examiner(s): Nguyen, Huy D
• Application Number:
  US11/411,881
• Publication Number:
  US 20060247890A1
• Time in Patent Office: 1,244 Days
• Field of Search: 455/456.1, 455/456.2, 455/456.6, 455/456.5
• US Class Current: 455/456.1
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: G01S 5/0054 of actual mobile position, i.e. position calculation on base station
• CPC Class Codes: G01S 5/0294 Trajectory determination or predictive filtering, e.g. target tracking or Kalman filtering

Abstract

A location estimating apparatus 10 has an information acquiring part 12, an information storing part 18, and an arithmetic processing part 20. The information acquiring part 12 has a location information acquirer 14 for acquiring location information of a mobile object from information, and an error information acquirer 16 for acquiring error information from information. The information storing part 18 stores the location information and error information sent from the information acquiring part 12, at each measurement time. The arithmetic processing part 20 estimates a location from the location information and error information from the information acquiring part 12. The arithmetic processing part 20 of the location estimating apparatus estimates the location of the mobile object by successively executing a first step of estimating a moving area per unit time of the mobile object, a second step of estimating an existing area at present of the mobile object, and a third step of estimating a location at present of the mobile object. This makes it feasible to provide location estimating means capable of achieving a high matching rate with an actual state, without use of other device information, while effectively utilizing information.

Claims

1. A location estimating apparatus comprising:

information acquiring means for acquiring location information pieces and error information pieces of a mobile object measured at present and at a plurality of time points in the past; and

arithmetic processing means for arithmetically processing the location information pieces and the error information pieces acquired by the information acquiring means, for estimating a moving area per unit time of the mobile object from the location information pieces and the error information pieces of the mobile object measured at a plurality of time points in the past, acquired by the information acquiring means, for estimating an existing area at present of the mobile object from the moving area per unit time of the mobile object and from the location information piece and the error information piece of the mobile object measured at a time point in the past, acquired by the information acquiring means, and for estimating a location at present of the mobile object from the existing area at present of the mobile object and from the location information piece and the error information piece of the mobile object measured at the present time, acquired by the information acquiring means.

2. The location estimating apparatus according to claim 1, wherein the arithmetic processing means estimates the moving area per unit time from the location information pieces and the error information pieces of the mobile object measured at a plurality of time points in the past, acquired by the information acquiring means, until an area of the moving area estimated per unit time is not more than a certain value.

3. The location estimating apparatus according to claim 1, wherein the arithmetic processing means provides a point value based on the error information pieces to the moving area estimated per unit time and estimating the moving area per unit time from the location information pieces and the error information pieces of the mobile object measured at a plurality of time points in the past, acquired by the information acquiring means, until the point value is not less than a certain value.

4. The location estimating apparatus according to any one of claims 1 to 3, wherein the arithmetic processing means estimates the existing area at present of the mobile object from the moving area per unit time of the mobile object and from the location information pieces and the error information pieces of the mobile object measured at a plurality of time points in the past, acquired by the information acquiring means.

5. A location estimating method comprising:

a first step of estimating a moving area per unit time of a mobile object from location information pieces and error information pieces of the mobile object measured at a plurality of time points in the past;

a second step of estimating an existing area at present of the mobile object from the moving area per unit time of the mobile object and from the location information piece and the error information piece of the mobile object measured at a time point in the past; and

a third step of estimating a location at present of the mobile object from the existing area at present of the mobile object and from the location information piece and the error information piece of the mobile object measured at the present time.

6. The location estimating method according to claim 5, wherein the first step comprises estimating the moving area per unit time from the location information pieces and the error information pieces of the mobile object measured at the plurality of time points in the past, until an area of the moving area estimated per unit time is not more than a certain value.

7. The location estimating method according to claim 5, wherein the first step comprises giving a point value based on the error information pieces to the moving area estimated per unit time and estimating the moving area per unit time from the location information pieces and the error information pieces of the mobile object measured at the plurality of time points in the past, until the point value is not less than a certain value.

8. The location estimating method according to any one of claims 5 to 7, wherein the second step comprises estimating the existing area at present of the mobile object from the moving area per unit time of the mobile object and from the location information pieces and the error information pieces of the mobile object measured at a plurality of time points in the past.

9. A location estimating apparatus, comprising:

a receiver configured to acquire location information pieces and error information pieces of a mobile object measured at present and at a plurality of time points in the past; and

a processor configured to arithmetically process the location information pieces and the error information pieces acquired by the receiver, to estimate a moving area per unit time of the mobile object from the location information pieces and the error information pieces of the mobile object measured at the plurality of time points in the past, acquired by the receiver, to estimate an existing area at present of the mobile object from the moving area per unit time of the mobile object and from the location information piece and the error information piece of the mobile object measured at a time point in the past, acquired by the receiver, and to estimate a location at present of the mobile object from the existing area at present of the mobile object and from the location information piece and the error information piece of the mobile object measured at the present time, acquired by the receiver.

10. The location estimating apparatus according to claim 9, wherein the processor is configured to estimate the moving area per unit time from the location information pieces and the error information pieces of the mobile object measured at the plurality of time points in the past, acquired by the receiver, until an area of the moving area estimated per unit time is not more than a certain value.

11. The location estimating apparatus according to claim 9, wherein the processor is further configured to provide a point value based on the error information pieces to the moving area estimated per unit time and estimate the moving area per unit time from the location information pieces and the error information pieces of the mobile object measured at the plurality of time points in the past, acquired by the receiver, until the point value is not less than a certain value.

12. The location estimating apparatus according to any one of claims 9 to 11, wherein the processor is configured to estimate the existing area at present of the mobile object from the moving area per unit time of the mobile object and from the location information pieces and the error information pieces of the mobile object measured at the plurality of time points in the past, acquired by the receiver.