Patent · US Expired

Tunable filter and method of tuning a filter

US6778023B2 · kind B2 · utility

318Cited by
9References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 31, 2001
Grant dateAug 17, 2004
Priority date
Expiry dateJul 31, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03J2200/10
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A bandpass filter is tuned by converting the filter into an oscillator using a negative resistance circuit, tuning the oscillator by using conventional tuning techniques such as tuning a varactor via a phase locked loop, sampling and holding the tuning signal and switching off the negative resistance circuit to convert the oscillator back into a bandpass filter.

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