We propose a new formulation for high-efficiency modes of power amplifiers in which both the in-phase and out-ofphase components of the second harmonic of the current are varied, in addition to the second harmonic component of the voltage. A reduction of the in-phase component of the second harmonic of current allows reduction of the phase difference between the voltage and current waveforms, thereby increasing the power factor and efficiency. Our proposed waveforms offer a continuous design space between the class B/J continuum and continuous F-1 achieving an efficiency of up to 91% in theory, but over a wider design space than F-1. These waveforms require a short at third and higher harmonic impedances which are easier to achieve at higher frequency. The fabricated amplifier using a GaN HEMT CGH40010F achieves 79.7% drain efficiency and 42.2 dBm saturated output power at 2.6 GHz, which gives a frequency weighted efficiency of 92.4% with this device.

No abstract

This is a repository copy of Development of GaN transducer and on-chip concentrator for galvanic current sensing.

This is a repository copy of An Integrated on-chip flux concentrator for galvanic current sensing.

Continuum mode amplifiers, which rely on harmonic tuning, have shown their potential for high efficiency over large bandwidths below 6 GHz and are strong candidates for even higher frequency applications of 5G networks. An accurate model of the transistor up to the third harmonic is a necessity for exploiting these amplifier classes. In this work, we present the considerations and challenges associated with modelling the device, and in particular the impact of extrinsic parasitics, for operation at high frequencies. We present a modified version of Dambrine's extraction procedure of intrinsic elements at sub-6 GHz frequencies, and demonstrate its utility up to 80 GHz by application in the extraction of a simulated GaN HEMT .