Employing Surface Waves for Characterizing Skin: Experimental Validation

Microwave technology has recently been explored as a non-invasive method for skin cancer diagnosis. While most research has focused on reflection signal analysis, transmission-based approaches remain under-explored. In this work, surface wave transmissions generated by two antennas are employed to characterize skin cancer in a non-invasive way. We refined the theoretical model proposed in our previous work, showing that the transmission coefficient (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$S_{21}$</tex-math></inline-formula>) amplitude and phase shift can effectively indicate both the presence and the size of skin tumors. Controlled experiments were conducted to validate the theory, using oil-gelatin-based phantoms to mimic both healthy skin and malignant tissue with varying tumor sizes. The experimental results strongly support the theoretical predictions and align with the simulation outcomes from our previous study.