Angle-selective surface made of multi-layered frequency-selective surfaces

• Main Author: Chen, Leo Xing Rong
• Other Authors: Shen Zhongxiang
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Electrical and electronic engineering::Antennas, wave guides, microwaves, radar, radio
• Online Access: https://hdl.handle.net/10356/167485
• Institution: Nanyang Technological University

Angular Selective Surfaces (ASS), which derives from the study of frequency selective surface (FSS), alter a surface’s construction to allow for certain angles of incident electromagnetic (EM) waves to pass through while inhibiting other angles. It serves to filter the input waves as either a band-pass, band-stop, high-pass or low-pass filter to allow for a desired output. A filtering process allows for better differentiation from noise and actual data that is being transmitted. Despite the number of studies in the realm of FSS, the study of ASS is far less which may overlook the usefulness in real world applications where transmitted frequencies are subjected to changes in angle with respect to the plan it is incident on. Therefore, this final year project evaluates a single layer model ASS and alters it by adding a through hole via and a matching pattern to the substrate's opposing plane. To further understand the implications of parametric adjustments, it was researched and simulated in ANSYS HFSS. Finally, a bilayer stack with a well-calculated air gap based on the circuit susceptance was used to obtain angular selectivity under TE polarization producing a band-pass and band-stop resonance in the microwave band. The |S21| above -1dB is simulated when theta is less than 13 degrees and drops to below -20dB for more than 34 degrees.