Novel dual resonant air gap antenna for defence systems, earth exploration-satellite, land mobile, radio determination application, weather satellite and broadcasting satellite applications

Abstract

This paper emphasizes on the design and performance analysis of dual resonant air gap antenna design. The proposed antenna has been designed using Flame Retardant 4 (ΓΚ4) substrate of dielectric constant, εr=4.4 sandwiched between copper patch and ground plane. The design o f antenna has been made to ensure the compact size of the designed antenna and operating bandwidth of 1.007 GHz (7.281 GHz-8.288 GHz) and 560MHz (11.57 GHz-12.13 GHz). The antenna has been fe by microstrip feed line via impedance transformer to match the impedance of proposed antenna with the 50Ω impedance of coaxial connector used for feeding power to the antenna. The proposed antenna has been designed and simulated in CST Microwave Studio 2014. This antenna resonates at frequency of 7.94 GHz with the minimal return loss of −33.64 dB with an impedance bandwidth of 47.97 Ω covering the frequency range from 7.281 GHz-8.288 GHz and −30.37 dB at 11.855 GHz covering the frequency of 11.57 GHz-12.13 GHz. The antenna has gain of 6.43 dB, directivity of 7.13 dBi and percentage bandwidth of 11.92% and 4.72% at resonant frequency of 7.942 GHz and 11.855 GHz respectively. The designed antenna can be suitably employed for Defence systems (7.25 GHz–8.215 GHz), Earth exploration satellite (8.02 GHz-8.215 GHz), Land mobile (8.02 GHz-8.215 GHz), Radio determination application (7.25 GHz–8.215 GHz), Weather satellite (7.45 GHz-7.55 GHz), Broadcasting satellite (11.7 GHz-12.5 GHz) applications. The antenna has been fabricated and efficaciously tested using E5071C network analyzer and anechoic chamber. It has been perceived that the practical results closely match with the simulated results.