Novel Antennas for mm-Wave and Microwave Systems

The emergence of high-performance antennas based modern manufacturing technology and novel additive processing is becoming a hot topic. Specifically, the substrate integrated waveguide (SIW) has demonstrated its impact in miniaturization, planarization, and low-cost manufacturing of transmission lines, while 3D printing technology has enabled the creation of customized, high-performance antennas. The research into SIW and 3D printed antennas are emergence for the advancement of wireless communication systems. In this thesis, novel millimeter-wave and microwave antennas based on modern and newly emerged additive manufacturing are investigated. First of all, in terms of novel antenna designs based on traditional manufacturing, several SIW-based planar directional antennas are presented in achieving high gain, miniaturization, easy integration and design simplification. They are i) SIW H-plane horn antenna with gradient air slots, ii) SIW H-plane horn antenna with an embedded air cavity; iii) SIW H-plane horn antenna loaded with linear dipole directors. Then, in terms of novel antenna designs based on 3D printing technologies, a variety antenna structures were proposed and studied. They are i) Fused deposition modelling (FDM) printed E-plane horn for gain enhancement; ii) Liquid crystal display (LCD) printed horn antennas for size reduction; iii) LCD printed horn antenna for beam-steering; iv) LCD printed rod antenna with modified permittivity for high gain; v) LCD printed dielectric lens for high directivity. All antenna designs including the concepts and design process presented are theoretically analyzed and introduced. They are fabricated and measured. The main contribution includes the novel antenna designs in both modern and additive manufacturing technologies for superior radiation performance and various design purposes