Transmitter linearized in response to signal magnitude derivative parameter and method therefor
US8615208B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 2011 |
| Grant date | Dec 24, 2013 |
| Priority date | — |
| Expiry date | Nov 18, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B2001/045
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A transmitter (50) includes a low power nonlinear predistorter (58) that inserts predistortion configured to compensate for a memoryless nonlinearity (146) corresponding to gain droop and another memoryless nonlinearity (148) corresponding to a video signal. When efforts are taken to reduce memory effects, such as configuring a network of components (138) that couple to an HPA (114) to avoid resonance frequencies within a video bandwidth (140), high performance linearization at low power results without extending linearization beyond that provided by the memoryless nonlinear predistorter (58). A look-up table (282) has address inputs responsive to a magnitude parameter (152) of a communication signal (54), a magnitude derivative parameter (204) of the communication signal (54), and possibly one or more variable bias parameters (85). The look-up table (282) produces a gain-correcting signal (284) that adjusts the gain applied to the communication signal (54) prior to amplification. The look-up table (282) is updated in response to an LMS control loop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.