Low noise amplifiers
US4264871A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 16, 1979 |
| Grant date | Apr 28, 1981 |
| Priority date | — |
| Expiry date | Apr 16, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/26
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Circuits are described which optimize the signal-to-noise ratio of a signal amplifier by means of active circuits which simulate low-noise resistors. When such "absorbers" or "desorbers," as they are termed, are used in amplifier circuits with signal sources characterized by equivalent thermal noise resistances they provide low-noise means for matching the source and amplifier for optimum noise behavior. In accordance with the invention therefore, it is possible to utilize active circuit elements such as transistors or op-amps in such a way as to realize amplifiers which have better noise figures than conventional amplifiers fabricated of the same circuit elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.