In the quest for efficient wireless communication, can a parallel-circuit Class-E power amplifier deliver? This paper presents the analysis and implementation of a single-ended high-efficiency broadband parallel-circuit (PC) Class-E power amplifier (PA) incorporating a single reactance compensation technique (RCT) and low-pass (LP) Chebyshev impedance transformer. Aimed at low supply voltage applications, the analysis focuses on gate and drain voltage optimization for achieving desired PA design goals. The study provides a detailed derivation and design procedure for the broadband matching network (MN), which effectively filters out higher-order harmonics and simplifies the circuit. It also explores the load adaptability of the PA, demonstrating drain efficiency (DE) exceeding 67.87% under load mismatch conditions. Experimental results from a PC Class-E PA based on an NMOS transistor validate the analysis, showing 36.48–38.83 dBm output power with 84.91% to 86.91% DE over a 7–9.4 MHz frequency band, operating at a low supply voltage of 12 V. This research pioneers the design of a broadband PC Class-E PA under low supply voltage for Internet of Things (IoT) applications at the HF frequency band, such as electronic article surveillance (EAS) systems. The findings showcase the potential for compact, high-efficiency radio frequency identification transmitters.
Published in the International Journal of Circuit Theory and Applications, this work directly aligns with the journal's focus on advancing circuit theory and its applications. The paper presents an innovative design for a high-efficiency power amplifier, a topic central to the journal's readership and scope.