Low distortion amplifier
US5589797A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1995 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | Sep 26, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/372
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Disclosed is a low distortion amplifier circuit of the predistortion type that employs a cuber circuit in the predistortion path to provide optimized signal energy at third order intermodulation frequencies, which cancels IMD products generated by the main power amplifier. The cuber circuit employs a pair of anti-parallel diodes that are biased with at least one D.C. source to produce a D.C. current flow through each diode. The input signal applied to the cuber circuit produces signal current flow in each diode to enable a third order output current to be extracted. A desired amount of third order power is thereby provided to realize minimal IMD power in the main amplifier output over a wide dynamic range of the input signal. Using a circuit analysis based on a power series approach, circuit parameters of the cuber circuit can be optimized to provide a desired amount of cancellation of third order IMD products in the main amplifier, without generating excessive higher order power, over an optimized dynamic range of the input signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.