Complex waves excited by an open-ended coaxial probe in layered media

Summary form only given. When an open-ended coaxial probe is placed against a material layer which is backed by air, surface wave modes can be excited in the layer. When the probe is placed against a material layer which is shorted by a metallic plate, radial guided waves can be excited in the layer. The excitation of these guided electromagnetic (EM) waves may affect the input impedance of the probe, thus influencing the quantification of EM properties of materials. The excitation of the complex waves by a probe in a layered medium was theoretically analyzed. A series of experiments was conducted to measure the input impedance of an open-ended coaxial probe placed against a layered medium. The effects of the excitation of complex waves on the probe input impedance and its consequences on the quantification of EM properties of the layered material were studied.<>