Effect of substrate temperature dependence on six-port reflectometer performance

This paper first investigates the effect of substrate temperature dependence on performances of six-port reflectometer (SPR) designed for measuring complexity permittivity. The temperature-dependent effect on the substrate is described by the variation of dielectric constant (έ_r) and dissipation factor (tanδ). Here, two printed circuit boards (RO3003^® and RO3010^®) with two different substrate materials are used for designing the SPRs operating at 4 GHz. The accuracy of these SPRs to predict moisture content in rubber latex over a certain temperature range will be studied. The obtained results indicate that the temperature dependent of the substrate has an impact on the SPR performances.