DYNAMICALLY BIASING CLASS AB POWER AMPLIFIERS OVER A RANGE OF OUTPUT POWER LEVELS

摘要

A method and apparatus for dynamically biasing a class AB RF power amplifier (PA) over a range of output power levels. A memory 112 holds a table that maps a required output power to the PA from a set of bias point parameters that provide a substantially constant relative power amplifier linearity level for the PA over an output power range of the power amplifier. A bias circuit 104 biases the PA. A processor 106 obtains an output power level from the PA, recalls the bias point table from the memory, maps the power level to the corresponding bias point parameters, and directs the bias circuit to bias the power amplifier in response to the mapped bias point parameters to provide an optimal linearity performance over an operating output power range of the PA.