Patent · US Expired

Low-noise amplifying circuit

US7057457B2 · kind B2 · utility

10Cited by
8References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 19, 2002
Grant dateJun 6, 2006
Priority date
Expiry dateJul 16, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03F2203/7236
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A low-noise amplifier circuit is specified which has a switchable gain ratio. For this purpose, a parallel circuit comprising a first and a second current path (3, 4) is provided between a radio-frequency signal input and output (1, 2), with the first current path (3) having a transistor which is connected in a common-base circuit for signal amplification, and the second current path (4) having a transistor which is connected in a common-emitter circuit (7) for signal amplification, and has input impedance matching (25, 27). Owing to the good noise characteristics and the good linearity characteristics, the described low-noise amplifier circuit is suitable for use in radio-frequency receivers in which adaptive pre-amplification is required even before a frequency converter, that is to say at the radio-frequency level, because the input signal has a wide dynamic range, such as that in the case of UMTS.

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