This project centred around optimising the efficiency of a 4G power amplifier using a dynamic power supply, and adaptive load pull techniques aimed at low cost M2M applications.
We were able to automate a test rig to explore various operating points whilst transmitting real-world 4G signals to achieve improvements in power added efficiency of between 27 and 44%. A fully calibrated test facility incorporated reference power detectors, power supplies, tuners and a base station emulator.
Further work consisted of miniaturising the tuner component to provide a varying reflection coefficient to the power amplifier, in order to optimise efficiency. Both CMOS and MEMS switched reactive loads were evaluated in order to achieve this.
