Patent · US Expired

Variable frequency synthesizer with reduced phase noise

US4602220A · kind A · utility

134Cited by
4References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 14, 1985
Grant dateJul 22, 1986
Priority date
Expiry dateAug 14, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03L7/20
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A reference signal from a reference signal source is supplied to a frequency transformer and a side band signal generator. The frequency transformer is formed mainly by up-converters and produces a frequency m times as high as the frequency f.sub.s of the reference signal. The side band signal generator outputs signals of base and harmonic frequencies f.sub.s, 2f.sub.s, 3f.sub.s, . . . and nf.sub.s (where n is less than m) and produces less phase noise than does the frequency transformer. The outputs of the frequency transformer and the side band signal generator are frequency mixed by a frequency mixer, and one frequency component in the frequency-mixed output is selected by a variable filter.

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