Positioning system, positioning apparatus, positioning information providing apparatus, positioning method, control program for positioning system, and computer readable recording medium having recorded therein control program for positioning system

• US 20060066478A1
• Filed: 09/21/2005
• Published: 03/30/2006
• Est. Priority Date: 09/24/2004
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kurata, Tomoyuki, Maruyama, Akira
• Granted Patent: US 7,408,503 B2
• Time in Patent Office: Days
• US Class Current: 342/357.640
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 19/28 Satellite selection

Abstract

A positioning system is provided to set easily initial position information at a low cost without using a database in which positions of base stations are stored. A GPS server 200 has a server positioning section 210a that receives a position related signal transmitted by a GPS satellite to obtain data. A server-orbit-information acquiring program 232 analyzes the data to generate orbit information 262 and stores orbit information 262 in a server third storing unit 260 (ST30). A satellite-direction-information generating program 234 generates satellite direction information 264a, which includes an elevation angle and an azimuth angle of the GPS satellite viewed from a reference point (ST31). A generation-time-information generating program 236 acquires the time when the satellite direction information 264a is generated from a server clock section 218a and stores the time in the server third storing unit 260 (ST32).

Claims

1. A positioning system comprising:

a positioning apparatus being configured to perform positioning utilizing positional information satellites;

a positioning information providing apparatus being configured to provide positioning information being used by said positioning apparatus to generate an initial position information indicating a general position of said positioning apparatus;

a communication network being configured to allow said positioning apparatus to communicate with said positioning information providing apparatus; and

a base station being configured to mediate communication between said positioning apparatus and said positioning information providing apparatus,

the positioning information providing apparatus including

an orbit information acquiring section on a positioning information providing apparatus side acquiring orbit information indicating orbits of said positional information satellites,

a reference-point-information storing unit on a positioning information providing apparatus side storing reference point information indicating coordinates of a reference point serving as a reference to calculate said initial position information,

a satellite-direction-information generating section generating satellite direction information indicating elevation angles and azimuth angles of said positional information satellites at said reference point on the basis of said orbit information and said reference point information,

a time information generating section generating time information indicting a time when said positioning information providing apparatus generates said satellite direction information, and

a positioning information transmitting section transmitting said positioning information to said positioning apparatus in response to a request from said positioning apparatus, and

said positioning apparatus including

an orbit information acquiring section on a positioning apparatus side acquiring said orbit information,

a reference-point-information storing unit on said positioning apparatus side storing said reference point information,

a positioning information acquiring section acquiring said satellite direction information and said time information from said positioning information providing apparatus through said communication network,

a satellite distance information generating unit generating satellite distance information indicating distances between said reference point and said positional information satellites on the basis of said reference point information and said satellite direction information,

a satellite-general-position-information generating section generating satellite general position information indicating general positions of said positional information satellites at the time when the satellite direction information is generated on the basis of said reference point information and said satellite direction information,

a satellite-present-position-information generating section generating satellite present position information indicating positions of the positional information satellites at a point when said positioning apparatus performs positioning on the basis of said orbit information, and

an initial-position-information generating section generating said initial position information on the basis of said reference point information, said satellite general position information, and said satellite present position information.

2. A positioning system according to claim 1, wherein said positioning apparatus includes an elevation angle/distance-associating-information storing unit that stores elevation angle/distance associating information that associates elevation angles of said positional information satellites and said satellite distance information, and said satellite-distance-information generating section generates said satellite distance information on the basis of said elevation angle/distance-associating information.

3. A positioning system according to claim 1, wherein said positioning information providing apparatus includes a maximum-elevation-satellite selecting section that selects a maximum elevation satellite that is a positional information satellite having the largest elevation angle at the reference point at a point when said positioning information is generated apart from said positional information satellite, and said positioning information providing apparatus provides said positioning apparatus with said satellite direction information, said satellite distance information, and said time information for said maximum-elevation satellite.

4. A positioning information providing apparatus that provides a positioning apparatus that performs positioning utilizing positional information satellites with positioning information that the positioning apparatus uses in order to generate an initial position information indicating a general position of the positioning apparatus through a communication network and a base station mediating communication, the positioning information providing apparatus comprising:

an orbit information acquiring section on a positioning information providing apparatus side acquiring orbit information indicating orbits of the positional information satellites;

a reference-point-information storing unit on a positioning information providing apparatus side storing reference point information indicating coordinates of a reference point serving as a reference to calculate the initial position information;

a satellite-direction-information generating section generating satellite direction information indicating elevation angles and azimuth angles of the positional information satellites at the reference point on the basis of the orbit information and the reference point information;

a time information generating section generating time information indicting time when the positioning information providing apparatus generates the satellite direction information and satellite distance information; and

a positioning information transmitting section transmitting the positioning information to the positioning apparatus in response to a request from the positioning apparatus.

5. A positioning apparatus that performs positioning utilizing positional information satellites, the positioning apparatus comprising:

an orbit information acquiring section on a positioning apparatus side being configured to acquire orbit information;

a reference-point-information storing unit on a positioning apparatus side storing the reference point information;

a positioning information acquiring section being configured to acquire satellite direction information and time information from the positioning information satellite through a communication network;

a satellite distance information generating unit being configured to generate satellite distance information indicating distances between a reference point and the positional information satellites on the basis of said reference point information and said satellite direction information;

a satellite-general-position-information generating section being configured to generate satellite general position information indicating general positions of the positional information satellites at the time when the satellite direction is generated on the basis of said reference point information and said satellite direction information;

a satellite-present-position-information generating section being configured to generate satellite-present-position- information indicating positions of the positional information satellites at a point when the positioning apparatus performs positioning on the basis of said orbit information; and

an initial-position-information generating section being configured to generate initial position information on the basis of said reference point information, said satellite general position information, and said satellite present position information.

6. A positioning method comprising:

Acquiring orbit information indicating orbits of the positional information satellites on a positioning information providing apparatus side S4 an orbit information acquiring section on said positioning information providing apparatus side of a positioning information providing apparatus, providing a positioning apparatus being configured to perform positioning utilizing positional information satellites with positioning information being used by send positioning apparatus to generate initial position information indicating a general position of said positioning apparatus through a communication network and a base station being configured to mediate communication;

storing reference point information indicating coordinates of a reference point serving as a reference to calculate said initial position information indicating a general position of said positioning apparatus on said positioning information providing apparatus side by a reference-point-information storing unit on said positioning information providing apparatus side of said positioning information providing apparatus;

a generating satellite direction information indicating elevation angles and azimuth angles of said positional information satellites at a reference point on the basis of said orbit information and said reference point information a satellite-direction-information generating section of said positioning information providing apparatus;

generating time information indicating time when said positioning information providing apparatus generates said satellite direction information by a time information generating section of said positioning information providing apparatus;

transmitting step said positioning information to said positioning apparatus in response to a request from said positioning apparatus by a positioning information transmitting section of said positioning information providing apparatus;

acquiring orbit information on said positioning apparatus side by an orbit information acquiring section on said positioning apparatus side of said positioning apparatus;

storing reference point information on said positioning apparatus side by a reference-point-information storing unit on said positioning apparatus side of said positioning apparatus;

acquiring step said satellite direction information and said time information from said positioning information providing apparatus through said communication network by a positioning information acquiring section of said positioning apparatus;

a satellite distance information generating step in which a satellite distance information generating unit of the positioning apparatus generates satellite distance information, which indicates distances between the reference point and the positional information satellites, on the basis of the reference point information and the satellite direction information;

generating satellite distance information indicating distances between said reference point and said positional information satellites on the basis of said reference point information and said satellite direction information by a satellite-general-position-information generating section of the positioning apparatus;

generating satellite general position information indicating general position of said positional information satellites at the time when the satellite direction is generated on the basis of said reference point information and said satellite direction information by a satellite-present-position-information generating section of said positioning apparatus; and

generating satellite-present- position- information indicating position of said positional information satellites at a point when said positioning apparatus performs positioning on the basis of said orbit information by an initial-position-information generating section of said positioning apparatus.

7. A control program for a positioning system having code causes a computer to execute the positioning method of claim 6.

8. A computer readable recording medium having recorded therein the control program for a positioning system according to claim 7.