Technique to improve the bandwidth of microstrip antenna

Abstract

The objective of this project is to improve the bandwidth of microstrip antenna using the scaling technique. The wideband antennas give a significant impact to the wireless technology in order to offer better performances, nowadays. The antennas have been designed at WLAN frequency bands, between 2.4 GHz and 5.2 GHz. Different scaling factor have been used which are 1.02 and 1.05. The simulations have been done using Advance Design System (ADS) software from Agilent. The S parameter data for single element patch antenna from Momentum simulation have been modeled using microstrip lines in circuit environment. The FR4 boards with a thickness of 1.6 mm, dielectric constant of 4.5, loss tangent of 0.019 and conductor thickness of 0.03 mm have been considered throughout the simulation works. Fabrication was done at Wireless Communication Center (WCC), UTM, using ultraviolet exposure and etching process. The measurements have been done using Agilent Network Analyzer (8723ES). The radiation patterns of the antennas have been done in an anechoic chamber in WCC. The measurement result shows that the bandwidth of the antennas has been increased to 10.56% and 23.86% at frequency 2.4 GHz and 5.2 GHz respectively. While, the cross polar isolation for the antennas is in the range of 7 to 20 dB. The typical half power bandwidth (HPBW) of the LPA is 40° for E plane and 90° for H plane. The gains of the antennas were comparable with the standard gain of monopole antenna.