An Investigation into the Equivalnce of Radiation Characteristics of 90° Circular Sector Microstrip Antenna vis-à-vis Circular Microstrip Antenna

Abstract

In this work, authors have investigated feed-probe influence on radiation characteristics of 90° circular sector microstrip antenna (CSMA). It is observed that by exciting a 90° CSMA with a feed-probe at two different feed-probe positions, two different modes TM01 and TM21 can be excited within the antenna structure. The resonant frequencies of these two modes are different but both of these modes have broadside radiation patterns in E and H plane. It is also observed that a 90° CSMA resonating at higher order TM01 mode has nearly equivalent radiation characteristics with a circular microstrip antenna resonating at dominant TM11 mode resonating at nearly same frequency. Therefore, the 90° CSMA becomes a suitable alternative to a circular microstrip antenna.