Frequency agile annular ring microstrip antenna loaded with MOS capacitor

Abstract

A new techniques for designing the frequency agile annular ring microstrip antenna (ARMSA) is presented. The frequency agility is achieved by loading the MOS capacitor on annular ring microstrip antenna. Instead of controlling the resonance frequency by changing the radii of annular ring microstrip antenna, it is also possible by means of changing the gate bias voltage of MOS capacitor without altering the radii of annular ring microstrip antenna. The investigations based on cavity model are carried out for the various thickness of oxide (Si3N4) layer from 100 Å to 400 Å It is found that the maximum frequency agility 51.56% (1.65 GHz) is obtained for 100 Å and minimum frequency agility 30.31% (0.97 GHz) is obtained for 400 Å. © 2008 VSP.