A theoretical investigation on the quarter-wavelength model — part 1: analysis
Ying Liu, Yue Liu, Michael G. B. Drew
Abstract
Abstract The quarter-wavelength-mode has been widely used in microwave absorption material research for many years. Based on wave-cancellation method, it is proved in the first part of this work that the model fails for most cases. It is interesting that the principles underlining this work are not beyond those covered by fundamental college courses even though the improper model has been dominant in the field for long without correction. In the second part of this work, the correctness of results obtained are verified by formulae well-known to material scientists. The improper commonly used practice of characterizing material by reflection loss and impedance matching has been highlighted and replaced by the method of wave-cancellation for film.