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:
Nov. 09, 2004
Filed:
Dec. 15, 1997
Philip Hon Nghia Quan, Surrey, GB;
Richard Wyrwas, London, GB;
ICO Services Ltd., London, GB;
Abstract
A satellite communications system and method, where a satellite can pass messages between a user terminal and an earth station , as the satellite moves in an orbit ′ as indicated by arrow , comprises means for measuring the position of the user terminal , on the surface of the earth , relative to the nadir , by means of doppler shift measurements and propagation delay measurements between the satellite and the user terminal . Where more than one satellite is visible to the user terminal , combination means are employed using propagation delays to plural satellites , and/or recordal of the receipt times, by the user terminal , of timed broadcasts from one or more satellites to determine the propagation delay between the one or more satellites and the user terminal