A fast load-pull optimization for power-added efficiency under output power and ACPR constraints

In the future real-time optimization of reconfigurable radar transmitter power amplifiers, a typical optimization would seek the highest power-added efficiency (PAE) possible under constraints on adjacent-channel power ratio and delivered power. This paper describes a sequential, fast optimization algorithm to find the constrained optimum using experimental queries taken at sequentially selected load reflection-coefficient values. The algorithm is compared across multiple starting reflection-coefficient values on the Smith chart and convergence to similar constrained optimum impedances and PAE values is demonstrated in both simulation and measurement. This algorithm is designed to allow reconfigurable radar transmitter amplifiers to optimize in real-time, meeting dynamically changing spectral mask, power efficiency, and output power requirements.