volume | PIER Journals

Abstract

A quasi-millimeter electromagnetic wave with the frequency of 22-30 GHz is applied to detect knots and holes in wood samples. It has better spatial resolution while keeping good transmission properties compared to microwave region used in the previous experiments. The images of knots and holes in wood are clearly obtained by analyzing the phase and amplitude of the transmitted wave. And the phase measurement results are all better than amplitude results according to phase values changing much more than amplitude.

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Professor Dan Zhang

Dr. Chujing Zong

Prof. Atsushi Mase