Patent · US Expired

Communication device

US7333533B2 · kind B2 · utility

1Cited by
6References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 2004
Grant dateFeb 19, 2008
Priority date
Expiry dateOct 30, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B2201/70715
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A communication device can reliably find a frequency and establish frequency synchronization, despite relying on a variable reference frequency, and may do so, e.g., by searching only during one or more periods of frequency stability. Once gained, such synchronization may be held continuously. An acquisition unit receives from a control unit information about a frequency change of a reference signal. The acquisition unit may nonetheless continue to search for, e.g., a satellite at the frequency that had been in use before the frequency change of the reference signal. An acquisition unit in such a device may search over extended periods, e.g., by using two or more frequency-stable periods. The acquisition unit may, e.g., transmit information about a change in the reference frequency to a tracking unit to maintain synchronization with the satellite.

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