Patent · US Expired

Onboard system in a vehicle and central system for locating the vehicle accurately

US6735521B1 · kind B1 · utility

1Cited by
22References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 30, 2000
Grant dateMay 11, 2004
Priority date
Expiry dateMar 30, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M2215/0196
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An onboard system determines the position of a vehicle from radio signals from a constellation of navigation satellites and periodically transmits to a traffic control center the position thus determined, a time label supplied by the constellation of navigation satellites and the identity of the vehicle. A central system for accurately locating at least one vehicle provided with a system of the above kind calculates the position at the current time as a function of the position and the speed vector of the vehicle and the time label transmitted by the vehicle. These systems can determine a position periodically and with great accuracy because the time label supplied by the constellation of navigation satellites can be used to compensate fluctuations in the transmission time between the vehicle and the traffic control center when the position is received in the traffic control center.

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