Dynamic Load Modulation of High Power Amplifiers with Varactor-Based Matching Networks

Abstract — In this paper, the results of dynamic load modu-lation on a high power amplifier is shown with experiments. A simple static nonlinear model is used as an inverse model, and by dynamically controlling both the input signal to the power amplifier and the load impedance, high efficiency operation of the power amplifier is achieved. The modulated measurements show the feasibility of dynamic load modulation for practical high power, high frequency applications. Index Terms — Efficiency, load modulation network, power amplifiers, tunable-matching networks. I