Patent · US Expired

Method of locating a fixed terminal using a constellation of satellites

US6195042A · kind A · utility

4Cited by
0References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 24, 1998
Grant dateFeb 27, 2001
Priority date
Expiry dateAug 24, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S5/0018
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method of locating a fixed terminal of a telecommunication system comprising a constellation of satellites, a plurality of gateway stations and a plurality of fixed terminals includes "coarse", "intermediate" and "fine" location phases. During the "intermediate" location phase, the terminal calculates at least three hyperboloids and their intersection, assuming a "coarse" estimated position of the terminal is known. Each hyperboloid can be written: EQU H.sub.i,j :dj-di=(tj'-tj).c-(ti'-ti).c where: PA1 di is the distance between the terminal and the position pi of the ith active satellite at time ti, PA1 dj is the distance between the terminal and the position pj of the jth active satellite at time tj, PA1 ti and tj are the ith and jth times of transmission by the ith and jth satellites, respectively, of ith and jth information relating to ti and di and to tj and dj, respectively, PA1 ti' and tj' are the ith and jth times of reception by the terminal of the ith and jth information, and PA1 c is the speed of light.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.