| PhD Seminar

Name of the Speaker: Ms. Masoom Verma (EE20D058)
Guide: Prof. David Koilpillai
Co-Guide: Dr. Christopher S
Online meeting link: meet.google.com/twp-kkwp-vqe
Date/Time: 6th January 2025 (Monday), 4:00 PM
Title: Innovative Solutions in Antenna Systems: From Omnidirectional Designs to Sectoral Coverage in A2G Communication System

Abstract :

This presentation will examine antenna systems used for omnidirectional applications, covering a range from basic omnidirectional passive antennas to advanced active sectoral coverage configurations. We have developed an omnidirectional array antenna with a conformal body that performs effectively in open areas. However, its radiation pattern distorts when situated under any Perfect Electric Conductor (PEC) body, leading to a pronounced null in the elevation radiation pattern due to destructive interference from reflections off the PEC. A typical scenario for this challenge is in Air-to-Ground (A2G) communication systems, where the antenna is located beneath the ventral fairing of an aircraft.

To address this issue, we propose a frustum-shaped array antenna that reduces ripple (the difference between null and peak) in the radiation pattern. Additionally, ensuring a high-capacity data link channel and reliability in A2G systems is accomplished by implementing sectoral beam steering. The array antenna is designed to operate within a frequency range of 4.4 GHz to 5 GHz, maintaining gain variation to within 5 dB across azimuthal coverage while ensuring adequate gain at shallow elevation angles. A 1:8 Wilkinson power divider has been designed to excite the eight elements. Furthermore, we propose a comprehensive analysis of switchable beams to cover a 45˚ sector, enhancing reliability through the proposed switching model. Another work introduces an innovative method for exciting the cavity-backed slot antenna, designed to minimize space requirements for L-Band.