The present invention provides an advanced adaptive 
predistortion linearization technique to dramatically reduce 
nonlinear distortion in power amplifiers over a very wide 
instantaneous bandwidth (up to 2 GHz) and over a wide range of 
amplifier types, input frequencies, 
signal types, amplitudes, temperature, and other environmental and 
signal conditions. In an embodiment of the invention, the 
predistortion linearization circuitry comprises (1) a higher-order polynomial model of an 
amplifier's 
gain and phase characteristics—higher than a third-order polynomial model; (2) an adaptive calibration technique; and (3) a 
heuristic calibration technique. The higher-order polynomial model is generated by introducing, for example, a plurality of multi-tone test signals with varying 
center frequency and spacing into the power 
amplifier. From the power amplifier's corresponding output, the nonlinearities are modeled by employing a higher-order curve fit to capture the irregularities in the 
nonlinear transfer function. Different 
distortion transfer functions can be implemented for different operating conditions. The adaptive calibration technique is based on a 
feedback analysis technique, which updates the applicable 
distortion transfer function by analyzing the 
error signal between the introduced input 
signal and the output signal in real-time. The 
heuristic calibration technique implements different 
distortion transfer functions based on historical operating conditions and optimal configurations of the power amplifier.