JultikaUniversity of Oulu repository

Abstract

Electromagnetic waves interact with different obstacles or materials. The propagation of electromagnetic waves depends on how they interact with different materials. Understanding the transmission and reflection characteristics of various media leads to understanding the propagation of electromagnetic waves. The transmission and reflection of radio waves are dictated by the dielectric properties of the material. The estimation of dielectric properties of a material is acquired by proper measurement techniques and methods. In this thesis, a measurement setup for assessing complex dielectric constant is verified. The measurement setup is designed with two high frequency horn antennas and a two-port vector network analyzer, controlled by a computer via a GPIB interface. Various measurement scenarios and results needed to achieve the goal are presented in the thesis. All measurements are done in an anechoic chamber. The measurement data is collected in frequency ranges of 1–9.5 GHz and 9.5–18 GHz. Furthermore, reflection measurements are taken from the side wall absorbers in the same anechoic chamber for checking the wall absorption characteristics. The key findings of this experiment are dielectric constant, Brewster angle and the reflection coefficient. The obtained value of the dielectric constant can be further used for similar type of environments or measurement setup.