Power amplifier pre-distortion
US7924942B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 18, 2003 |
| Grant date | Apr 12, 2011 |
| Priority date | — |
| Expiry date | Aug 14, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2201/3209
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A power amplifier pre-distorter is formed by a FIR filter structure which includes an individual look-up table for each filter tap, where each look-up table represents a sampled polynomial in a variable representing signal amplitude, and means for selecting, from each filter tap look-up table, a filter coefficient that depends on the amplitude of a corresponding complex signal value to be multiplied by the filter tap. A training method for such a pre-distorter determines (S1) a first estimate of a first look-up table assigned to a first filter tap, assuming a second look-up table assigned to a second filter tap is set to predetermined table values. Thereafter the method determines (S2) a second estimate of the second look-up table, assuming the first look-up table is set to the determined first estimate. If deemed necessary, the method includes the further steps (a) refining (S3) the first estimate refined, assuming the second look-up table is set to the latest determined second estimate, and (b) refining (S4) the second estimate, assuming the first look-up table is set to the latest determined first estimate. Steps (a) and (b) may be repeated (S5) until convergence is reached.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.