Class-F PA Design Based on a New Analytical Formulation
Class-F power amplifier (PA) design has traditionally involved terminating even harmonics with a short circuit and odd harmonics with an open circuit. In practice, this is impossible to achieve over any useful bandwidth as it is based on idealized assumptions that lead to an intractable solution, whereby the third harmonic voltage amplitude is zero divided by zero. This presentation puts the Class-F mode analysis back into the tractable world, mainly through the inclusion of a novel but realistic model for the I-V knee region of the device. This results in a set of equations that can be solved, leading to useful practical design guidelines. In particular it is shown that the requirement for an open circuited third harmonic can be substantially relaxed with only minor reduction in efficiency.
Presented by: Dr. Steve C. Cripps, Cardiff University