In this research paper, we propose an amplitude-only method for unique thickness evaluation of medium- and low-loss materials. The method is based on using amplitude-only measurements at different frequencies to evaluate the unique thickness. Main advantages of the method are a) it eliminates the necessity of repetitive measurements of different-length materials to evaluate the unknown thickness of the same type material and b) it determines the thickness at any desired frequency in the band. Because the method uses amplitude-only measurements and enables the thickness evaluation at any frequency, it can be a good candidate for thickness evaluation of materials in industrial-based applications.
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