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:
Oct. 02, 2001
Filed:
Sep. 09, 1998
Jin Dai, San Diego, CA (US);
Qualcomm Incorporated, San Diego, CA (US);
Abstract
An apparatus, method, and process for quickly and accurately determining the position of a user terminal in a satellite communications system. An initial coarse estimate of the radius of the Earth at a terminal position is made. The geometry of satellites being used and the user terminal is then determined. When only one satellite is used, the satellite-user terminal geometry includes the range and range rate of the satellite with respect to the user terminal. When two satellites are used, the satellite-user terminal geometry includes the range of each satellite with respect to the user terminal. An initial position estimate is determined based on the radius and the satellite-user terminal geometry. The coarse radius estimate can then be formed into a fine estimate and the initial position estimate further refined.