Gain and bandwidth enhancement of slotted microstrip antenna using metallic nanofilms for WLAN applications

Abstract

Structural modifications on microstrip patch antenna design for performance enhancement offer improvements and advantages only up to a certain limit. However, with the use of novel material in the patch area, the performance of a microstrip patch antenna can further be enhanced in terms of gain and bandwidth. In this paper, a nanomaterial-based slotted rectangular microstrip patch antenna is proposed for gain and bandwidth enhancement in Wireless Local Area Network (WLAN) applications. A conventional copper rectangular microstrip antenna (MSA) with a rectangular slot in the patch area is first fabricated and then nanomaterial is deposited in the slot area. Two types of metallic nanoparticulate thin films are deposited using Gold Nanoparticles (Au NPs) and a combination of alternate Silver-Gold-Silver Nanoparticles (Ag-Au-Ag NPs) in the slot area and the antenna parameters analyzed. A comparison between the conventional slotted MSA, and the fabricated antenna with the two different nanoparticulate thin films is presented. It is found that the Au NPs based antenna shows a 12.5 % improvement in bandwidth for a return loss of −31 dB and a 0.5 dB enhancement in gain with a nanomaterial film thickness of 264 nm. The composite Ag-Au-Ag NPs based antenna shows even better performance than the former one with an 18.75 % improvement in bandwidth for a return loss of −30 dB along with gain enhancement of 2 dB with a nanomaterial film thickness of 330 nm. Both the Au NPs and Ag-Au-Ag NPs based antennas are found to resonate at 5.89 GHz and 5.81 GHz showing an electrical size reduction of 32.09 % and 31.15 %, respectively compared to the conventional rectangular MSA.