Patent · US Expired

Frequency Reference Compensation

US5542095A · kind A · utility

12Cited by
13References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 24, 1993
Grant dateJul 30, 1996
Priority date
Expiry dateAug 24, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03J1/0008
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The present invention provides a frequency tracking and compensation system and methods for minimizing the frequency offset between remote and local units of a communications system. The system of the present invention resides in the local unit and comprises a downconverter, a digital transceiver, a processor, a reference oscillator and a frequency synthesizer. The downconverter mixes a signal received from the remote unit with a local oscillator (LO) signal generated by the frequency synthesizer. The frequency of the LO signal is based on the frequency of a reference signal generated by the reference oscillator. The system of the present invention utilizes the digital transceiver to determine a frequency offset of the received signal without comparing the received signal to the reference signal. The processor then utilizes the frequency offset to adjust the frequency of the reference signal. The method of the present invention accumulates the frequency offsets and compares the accumulated offset to a predetermined threshold. The reference frequency is adjusted if the accumulated offset exceeds the threshold. In one embodiment, the reference frequency is adjusted after complete rec…

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