Method for providing satellite orbit ephemeris, server, and positioning system

• US 8,446,315 B2
• Filed: 06/15/2009
• Issued: 05/21/2013
• Est. Priority Date: 06/19/2008
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Tomita, Kyoichi
• Primary Examiner(s): LIU, HARRY K
• Application Number:
  US12/484,634
• Publication Number:
  US 20090315773A1
• Time in Patent Office: 1,436 Days
• Field of Search: 342/357.44
• US Class Current: 342/357.66
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/258 relating to the satellite constellation, e.g. almanac, ephemeris data, lists of satellites in view
• CPC Class Codes: G01S 19/33 Multimode operation in different systems which transmit time stamped messages, e.g. GPS/GLONASS

Abstract

A method for providing satellite orbit ephemeris includes: determining a positioning satellite in view of a reference position; and providing to a positioning device a satellite orbit ephemeris of the positioning satellite in view of the reference position, the satellite orbit ephemeris being valid for at least one day.

Claims

1. A method for providing long-term ephemeris of a positioning satellite, the method comprising:

determining whether or not a positioning satellite is in view from a reference position in each of plural unit time, a predicted period of the long-term predicted ephemeris including the plural unit time, the predicted period being a predetermined period from generation of the long-term predicted ephemeris; and

providing the long-term predicted ephemeris including satellite orbit data of a unit time that the positioning satellite is in view from the reference position and not including satellite orbit data of a unit time that the positioning satellite is not in view from the reference position.

2. The method according to claim 1, wherein

the reference position is at least one of a position of the positioning device, a registered district, and a predetermined district for which the long-term predicted ephemeris is to be provided.

3. The method according to claim 1, further comprising

obtaining time series data of predicted positions for the positioning satellite;

extracting data of a unit time that the positioning satellite is in view from the reference position, from the obtained time series data; and

generating the long-term predicted ephemeris based on the data.

4. The method according to claim 3, wherein

the generating the long-term predicted ephemeris includes generating parameters of a predetermined approximate model expression based on the data .

5. The method according to claim 1, wherein

the determining whether or not the positioning satellite is in view includes determining that the positioning satellite is in view from the reference position in a unit time when an elevation angle of the positioning satellite is more than predetermined value in the unit term.

6. The method according to claim 1, wherein

the predicted period is at least one day.

7. A server for providing long-term ephemeris of a positioning satellite, the method comprising:

a determining unit that determines whether or not a positioning satellite is in view from a reference position in each of plural unit time, a predicted period of the long-term predicted ephemeris including the plural unit time, the predicted period being a predetermined period from generation of the long-term predicted ephemeris; and

a transmitting unit that transmits the long-term predicted ephemeris including satellite orbit data of a unit time that the positioning satellite is in view from the reference position and not including satellite orbit data of a unit time that the positioning satellite is not in view from the reference position.

8. A positioning system comprising:

a positioning device that measures a position using long-term predicted ephemeris; and

a server that provides the long-term predicted ephemeris to the positioning device,

the positioning device includes

a transmitting unit that transmits a reference position information to the server,

a receiving unit that receives the long-term predicted ephemeris from the server, and

a positioning unit that measures the position using the long-term predicted ephemeris,

the server includes

a determining unit that determines whether or not a positioning satellite is in view from a reference position in each of plural unit time, a predicted period of the long-term predicted ephemeris including the plural unit time, the predicted period being a predetermined period from generation of the long-term predicted ephemeris, and

a transmitting unit that transmits the long-term predicted ephemeris including satellite orbit data of a unit time that the positioning satellite is in view from the reference position and not including satellite orbit data of a unit time that the positioning satellite is not in view from the reference position.