Method of correcting nonlinearities of an amplifier, and radio transmitter employing a method of this type
US5903611A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 1997 |
| Grant date | May 11, 1999 |
| Priority date | — |
| Expiry date | Mar 20, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2201/3233
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In order to correct nonlinearities of an amplifier which receives a radio signal and produces an amplified radio signal representing an input complex digital signal, a predistortion table, associating a value of a predistorted complex digital signal with each value of the input complex digital signal, is stored, and the predistorted complex signal is modulated in order to obtain the radio signal addressed to the amplifier. In an adaptation period, a fraction of the amplified radio signal is demodulated in order to obtain a demodulated complex signal which is compared with the input complex signal, with which the predistorted complex signal modulated in said adaptation period is associated, in order to update the predistortion table. The predistortion table is updated on the basis of mean values calculated from blocks of samples of the input complex signal and of the demodulated complex signal, which are stored in the adaptation period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.