Patent · US Expired

Mixer noise reduction technique

US6748204B1 · kind B1 · utility

43Cited by
11References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 17, 2000
Grant dateJun 8, 2004
Priority date
Expiry dateMay 17, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03D2200/0043
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

In accordance with the present invention a mixer circuit noise reduction technique is provided. The mixer circuit of the present invention includes a gain stage for receiving a first signal and producing an output signal. The mixer circuit also includes a bias circuit coupled to the gain stage through a common node for providing a bias current to the gain stage, the bias circuit having an input for receiving a second signal, and in accordance therewith, varying the bias current. Additionally, the mixer circuit includes a frequency dependent current shunt circuit coupled between the common node and a reference voltage, wherein a first portion of the bias current frequency components within a first frequency range are coupled to the reference voltage by the shunt circuit, and a second portion of the bias current frequency components within a second frequency range are coupled to the reference voltage by the shunt circuit, the first portion being larger than the second portion. As a result, the noise in the mixer circuit is reduced while the gain is enhanced.

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