Applications of Origami Folding Techniques on Antenna Structures using Flexible Substrates

This thesis investigates the use of Origami folding techniques in antenna structures. This application would be suitable for space satellites and military secure communications. The main research is divided into three segments. The first one presents a Vivaldi antenna using flexible substrates, Kapton and Mylar. They are simulated in Computer Simulation Technology (CST) Studio and tested with a Vector Network Analyser (VNA) in the anechoic chamber. The reason for using various flexible substrates is to determine which substrate would perform better when folded. Each substrate has unique electrical and mechanical properties. Secondly, a more specfic Origami folding pattern called Miura Ori is introduced. It is integrated into two antenna designs: Slot antenna and Substrate Integrated Waveguide (SIW) antenna. The Miura Ori folding technique is a repeated pattern with some interesting mechanical properties. It would be able to switch between different states: at, partially folded or fully folded. This would be beneficial for applications where the cost, size and weight are limited. Both antenna designs are simulated and optimised to achieve a good performance, before incorporating the Miura Ori folding technique. There are special parameters that require the model to be functional, Inner angle and Folding angle. Each antenna is simulated by varying those two parameters, because of that the resonant frequency, reflection coefficient (S11), gain and the direction of the radiating angle is changed. Lastly, a microwave switch with nanowires is investigated to provide a fast switching network at each individual antenna. The microwave switch is simulated on a flexible substrate.