Patent · US Expired

Fast user terminal position determination in a satellite communications system

US6298238A · kind A · utility

22Cited by
21References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 9, 1998
Grant dateOct 2, 2001
Priority date
Expiry dateSep 9, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S5/12
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

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.

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