Dynamic Supply Voltage Control for PA Output Power Correction Under Variable Loading Scenarios

This article presents an automatic system that is able to dynamically restore the output power capability of a amplifier (PA) under variable loading scenarios. accomplished by adapting supply voltage, VDD, PA according developed theoretical model. To vary GaN dc-dc converter, based on commercial EPC 9067 Demo Board, was used. The load measured using impedance meter, which slotted line principle and specifically designed for low insertion loss. meter also generates load-dependent pulsewidth modulated signal controls converter switching, regulating VDD. prototype 3.55 GHz tested with CW excitations, being compensate degradation conditions inside 2.1 voltage standing wave ratio circle. For constant gain compression level, average efficiency over range impedances less than 5%, improvement 0.7 dB. worst case compensated from 37.0 39.9 dBm, corresponds 2.9 dB improvement. Using excitation, peak envelope power, compressed almost 3 without VDD compensation, restored, improved 0.6 can track adjust step-up delay 25 ms.