Class E amplifiers and their modulation behaviour

[摘要] The Class E power amplifier has very high drain efficiency under quasi-static conditions, and is a good candidate for Envelope Elimination and Restoration (EER) or other polar techniques. Unfortunately it has an unusual carrier frequency response, for which no analytic expression was known; this may have limited commercial use of the circuit. Two new steady state analyses are presented, which give the carrier frequency response in simple form, together with expressions for component values. Good agreement with measured data and existing numerical solutions is seen. Previous attempts at characterising the amplitude modulation (AM) behaviour of this circuit have assumed that it can be modelled as a first order low pass filter. It is shown that Class E AM can be modelled as an equivalent circuit, which behaves as a second order low pass filter. Measurements confirm the analysis.

[发布机构] University:University of Birmingham;Department:School of Engineering, Department of Electronic, Electrical and Systems Engineering

[关键词] T Technology;TK Electrical engineering. Electronics Nuclear engineering