Transmitter Linearized Using Bias Deviation Gain Adjustment And Method Therefor

摘要

A transmitter (50) includes a low power memoryless nonlinear predistorter (58) that inserts predistortion configured to address a nonlinearity (146) corresponding to gain droop and another nonlinearity (148) corresponding to deviations from an average bias condition. 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). Each nonlinearity is addressed by applying gain to a communication signal (54). The amount of gain applied is determined by a look-up table (170) for one nonlinearity (146) and by a look-up table (198) in combination with a differentiator (202) for the other nonlinearity (148). The look-up tables (170, 198) are updated in accordance with modified LMS control loops.