The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 12, 2011
Filed:
Mar. 18, 2009
Hung-sheng Chen, Taipei County, TW;
Hung-Sheng Chen, Taipei County, TW;
Altek Corporation, Hsinchu, TW;
Abstract
A method for obtaining a precise intermediate frequency for a global positioning system (GPS) is applied in a GPS receiver having a radio frequency (RF) module. Using a satellite signal received by the RF module, ephemeris data of a satellite is completely obtained, and present coordinate of the GPS receiver is calculated. First coordinate of the satellite at first time point and second coordinate of the satellite at second time point are calculated using the ephemeris data. Then, traveling speed of the satellite and projection value of the traveling speed on position vector from the first coordinate to the present coordinate are calculated using the first time point, the first coordinate, the second time point, and the second coordinate. Finally, the precise intermediate frequency is calculated using the signal frequency, a carrier frequency of the satellite, the projection value, and velocity of light.