Method of determining a gps position fix and a gps receiver for the same

• US 20060224317A1
• Filed: 04/28/2004
• Published: 10/05/2006
• Est. Priority Date: 05/07/2003
• Status: Active Grant

• Current Assignee: Titan Intelligence Technology Limited
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Sarkar, Amites
• Granted Patent: US 8,560,233 B2
• Time in Patent Office: Days
• US Class Current: 701/213
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/254 relating to Doppler shift of satellite signals
• 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 19/27 creating, predicting or correcting ephemeris or almanac data within the receiver

Abstract

A method of determining a GPS position fix is disclosed together with a corresponding GPS receiver and server for the same. The method comprising the steps of: (i) providing standard GPS ephemeris corresponding to that transmitted by a GPS satellite; (ii) providing supplemental GPS ephemeris including at least one parameter describing the fluctuation over time of at least one satellite orbit parameter of standard GPS ephemeris; (iii) measuring psuedoranges to GPS satellites; and (iv) determining a GPS position fix from both the standard and supplemental GPS ephemeris provided in steps (i) and (ii) respectively and the psuedoranges measured in step (iii).

Claims

1. A method of determining a GPS position fix comprising the steps of:

(i) providing standard GPS ephemeris corresponding to that transmitted by a GPS satellite;

(ii) providing supplemental GPS ephemeris including at least one parameter describing the fluctuation over time of at least one satellite orbit parameter of standard GPS ephemeris;

(iii) measuring psuedoranges to GPS satellites; and

(iv) determining a GPS position fix from both the standard and supplemental GPS ephemeris provided in steps (i) and (ii) respectively and the psuedoranges measured in step (iii).

2. A method according to claim 1 wherein the supplemental GPS ephemeris includes at least one parameter describing a frequency component of the fluctuation over time of at least one satellite orbit parameter of standard GPS ephemeris.

3. A method according to claim 2 wherein the or at least one of the frequency components corresponds to a lunar cycle.

4. A method according to claim 2 wherein the or at least one of the frequency components corresponds to a solar cycle.

5. A GPS receiver configured to determine a GPS position fix from (i) standard GPS ephemeris corresponding to that transmitted by a GPS satellite;

(ii) supplemental GPS ephemeris including at least one parameter describing the fluctuation over time of at least one satellite orbit parameter of standard GPS ephemeris; and

(iii) psuedoranges measured from the GPS receiver to GPS satellites.

6. A GPS receiver according to claim 5 wherein the supplemental GPS ephemeris includes at least one parameter describing a frequency component of the fluctuation over time of at least one satellite orbit parameter of standard GPS ephemeris.

7. A GPS receiver according to claim 6 wherein the or at least one of the frequency components corresponds to a lunar cycle.

8. A GPS receiver according to claim 6 wherein the or at least one of the frequency components corresponds to a solar cycle.

9. A GPS receiver according to claim 5 further configured to determine at least one parameter of the supplemental GPS ephemeris from a history of standard GPS ephemeris received directly from the GPS satellites by the GPS receiver.

11. A server according to claim 5 wherein the supplemental GPS ephemeris includes at least one parameter describing a frequency component of the fluctuation over time of at least one satellite orbit parameter of standard GPS ephemeris.

12. A server according to claim 11 wherein the or at least one of the frequency components corresponds to a lunar monthly cycle.

13. A server according to claim 11 wherein the or at least one of the frequency components corresponds to a yearly cycle.

10. A server configured to transmit to a remote GPS receiver supplemental GPS ephemeris including at least one parameter describing the fluctuation over time of at least one satellite orbit parameter of standard GPS ephemeris corresponding to that transmitted by a GPS satellite.