Characterization of wideband antenna with split ring resonator on hybrid material for WLAN application

• Main Author: Ong, Teik Kean
• Format: Thesis
• Language: English; English
• Published: 2017
• Subjects: T Technology (General); TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.utem.edu.my/id/eprint/20705/; https://plh.utem.edu.my/cgi-bin/koha/opac-detail.pl?biblionumber=106144

In this advancement of wireless technology era, antenna which acts as a transmitting and receiving metallic device is needed to be compact that to be embedded into a wireless communication system or device. Besides that, multiband or wideband antenna is more preferable as multiple applications that can be embedded into a single device. Metamaterials which is able to manipulate the electromagnetic properties are more likely to be used to replace some materials of antenna production which need higher cost and time of production. On the other hand, the using of hybrid material substrate on antenna can overcome the limitation of conventional monolithic antenna thickness which may lead to the characteristic on manipulating return loss, bandwidth, gain, and total efficiency of antenna. Thus, this project aims to characterize, design, simulate, and fabricate antenna with split ring resonator (SRR) structure and hybrid material substrate. At first, monopole antennas with coplanar waveguide (CPW) and coaxial feeding technique were designed as the basic antenna structure for further investigation. Both monopole antennas were constructed by a standing rectangular patch printed on a FR4 substrate and a flattened ground plane. Next, coaxial-fed monopole antenna design which was successfully fabricated had been embedded separately with SRR slot and hybrid material substrate which is constructed by FR4, Roger, and glass substrate to investigate the design parameters of both elements to the antenna. Lastly, both SRR slot and hybrid material substrate had been added to the coaxial-fed monopole antenna. All antenna designs in this project were simulated by using Computer Simulation Technology (CST) Microwave Suite software in open space environment. Investigation on SRR parameters had yielded the characteristic of SRR parameters in shifting the frequency band notch to lower or higher frequency region by scaling within 22MHz and 1.4GHz, as well as controlling the notching effect of the frequency band notch. Bandwidth expansion had also been achieved with 1.18GHz by the adding of hybrid material substrate to the antenna. Among all antenna designs, coaxial-fed monopole antenna with five SRR slots and hybrid material substrate had created two frequency band notches with widest covered bandwidth of 800MHz, lowest matching efficiency of 38.91%, lowest gain of -4.08dB, and lowest total efficiency of only 13.58%. Notably, this antenna can operate for IEEE 802.11 wireless local area network (WLAN) applications at 2.4GHz, 5.2GHz, and 5.8GHz with at least 90% matching efficiency, 1dB gain, 2dB directivity, and 50% total efficiency. Therefore, SRR slot and hybrid material substrate can be used to create frequency band notches for removing unwanted signals and enhance bandwidth for providing higher data transfer rate in antenna design.