Frequency band and operating class reconfigurable GaN HEMT power amplifier for sustainable wireless communications and energy applications

This paper presents design and implementation of a frequency band and operating class reconfigurable power amplifier. At the operating frequency of 2.45 GHz, the proposed power amplifier (PA) can be reconfigured to operate in class A or class B mode. Whereas class A mode represents an extreme high linearity and highly dispersive case, class B mode can offer high efficiency where high linearity is not strictly required e.g. for wireless power transfer. For data transfer, the typical operating class is class AB which is a compromise between highly linear class A and high efficiency class B. It has been proven in this work that all bias conditions between class A and B e.g. A, AB or B can be chosen with the proposed reconfigurable power amplifier concept whereas good matching at input and output are still provided. Simulation and measurement results are presented in case of a 2.45 GHz GaN HEMT operating class reconfigurable power amplifier. In addition, further extension of this concept has been presented with simulation results showing that frequency band reconfiguration can also be achieved with some modifications of the PA circuit. As a result, the proposed reconfigurable PA offers a versatility regarding operating class and frequency band which can support various applications with only a single hardware. Such flexibility of the RF frontend is advantageous for upcoming trends in wireless technology including wireless power transfer and software defined radio.