High-Efficiency Broadband Parallel-Circuit Class E RF Power Amplifier With Reactance-Compensation Technique

Abstract

Class E amplifier offers high efficiency approaching 100% for an ideal case. This paper introduces a first practical implementation of a novel broadband class E power amplifier design combining a parallel-circuit load network with a reactance compensation technique. The novel broadband parallel-circuit class E load network using reactance compensation technique has been discussed based on theory and its experimental verification. A proper guidelines method of designing a high-efficiency broadband class E power amplifier with an LDMOS transistor until the final prototype measurement and optimization will be discussed. In the measurement level, the drain efficiency of 74% at an operating power of 8 W and power flatness of 0.7 dB are achieved across a bandwidth of 136-174 MHz. The efficiency result is the highest result for VHF broadband frequency to date with a low supply voltage of 7.2 V. Simulations of the efficiency, output power, drain voltage waveform, and load angle (impedance) were verified by measurements and good agreements were obtained.