Active simultaneous harmonic source and load pull assisted by local polyharmonic distortion models

The efficiency of a power amplifier is a strong function of the core transistor technology and the circuitry that is wrapped around it. There are many theoretical approaches to obtaining full DC-to-RF conversion from an ideal transistor, however real-world technologies do not perform equally well with each. The parasitic reactances and non-ideal DC characteristics of a transistor technology result in matching and bias requirements that can deviate significantly from those of ideal theory. In this paper we describe the use of an active simultaneous source and load pull system that quickly ascertains the conditions required to achieve a transistor technology's peak efficiency performance. The speed with which the system is able to achieve these results is facilitated by local polyharmonic distortion models that provide a quick and reliable method for finding the path of steepest ascent.