Patent · US Expired

GPS satellite signal tracking method for GPS receivers

US5059969A · kind A · utility

21Cited by
7References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 7, 1990
Grant dateOct 22, 1991
Priority date
Expiry dateSep 7, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S19/29
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method for recapturing a satellite at the highest elevation angle as quickly as possible with a GPS receiver having a plurality of receiving channels when a state of receiving satellite signals recovers to normal after having been interrupted by obstacles like a tunnel, wherein a search range of satellite signal receiving frequency is divided into a plurality of frequency bands and each of which is assigned to the plurality of receiving channels in a one-to-one relationship, a search frequency of each receiving channel is changed in step wise for searching a satellite signal simultaneously in the receiving channels, and further, by providing a time difference for a step wise change-over timing of the search frequency between receiving channels, a time required for recapturing the satellite is greatly reduced by increasing a change to lock up one of the receiving channels with the satellite signal receiving frequency, since there are as many chances as a number of receiving channels within one cycle of the step wise search frequency change-over for one receiving channel.

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