Patent · US Active

Voltage controlled oscillator having reduced phase noise

US8102216B1 · kind B1 · utility

17Cited by
5References
19Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 6, 2009
Grant dateJan 24, 2012
Priority date
Expiry dateJul 28, 2029

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03B5/1228
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A VCO comprises an LC tank circuit coupled to a plurality of cross-coupled transistor devices. A first resonance frequency of a waveform output of the VCO is dependent upon the values of a first capacitor and a first inductor of the LC tank. The VCO further comprises a first series LC resonator comprising a second capacitor and a second inductor in parallel to the first capacitor and the first inductor. The values of the second capacitor and second inductor are selected to produce a second resonance frequency that is a third harmonic of the first resonance frequency, thereby increasing a slope of the voltage controlled oscillator output. The increased slope reduces phase noise, which leads to improved signal-to-noise ratio.

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