Investigation of low-permittivity hemispherical and Fresnel radio lens operated at sub-terahertz range

Abstract

This thesis explores the role of refractive and diffractive lenses in radio communication, focusing on their fabrication and functionality. The main goal is to examine how factors like lens shape, material properties, and manufacturing methods affect the performance of radio communication systems. The theoretical aspect includes a literature review that covers the basic principles of radio communication, the role of lenses in manipulating electromagnetic waves, and an overview of two types of lenses used in the thesis, their optical properties, and their interaction with radio frequency signals.

In addition to theoretical insights, the thesis involves practical measurements and analysis. It compares simulated and measured results to validate the lenses’ performance. Simulations were conducted using advanced software, requiring detailed conceptual and design knowledge. Measurements were performed in a controlled environment to minimize errors and ensure accuracy. The findings reveal a measured directivity of the low-permittivity refractive lens at 22.1 dBi at 170 GHz and a simulated directivity of the Fresnel lens at 32 dB at 300 GHz. This work provides a comprehensive understanding of how refractive and diffractive lenses impact radio communication systems, contributing to more efficient and optimized designs in the field.