G-shaped band-notched ultra-wideband MIMO antenna system for mobile terminals

• Published in: IET microwaves, antennas & propagation antennas & propagation, 2017-04, Vol.11 (5), p.718-725
• Main Author: Toktas, Abdurrahim
• Format: Article
• Language: English
• Subjects: antenna feeds; antenna radiation patterns; Antennas; diversity performance; frequency 2.2 GHz to 13.3 GHz; G‐shaped band‐notched ultra‐wideband MIMO antenna system; impedance matching; Local area networks; low‐profile band‐notched G‐shaped UWB MIMO antenna design; microstrip lines; microstrip transmission line; Microwave antennas; MIMO (control systems); MIMO communication; mobile antennas; mobile radio; mobile terminal; MTL; multiple input multiple output antenna design; reflection performance; Research Article; Strip; symmetrical square element feeding; Terminals; T‐shaped strip; UHF antennas; ultra wideband antennas; Ultrawideband; wireless LAN; wireless local area network band; Wireless networks; WLAN band
• ISSN: 1751-8725; 1751-8733; 1751-8733
• DOI: 10.1049/iet-map.2016.0820

Low-profile band-notched G-shaped ultra-wideband (UWB) multiple input multiple output (MIMO) antenna design for mobile terminals has been presented. In this context, two UWB MIMO antenna systems have been designed: The first is with square elements and the second is with G-shaped elements. An MIMO antenna with two symmetrical square elements each of 8 × 8 mm2 operating between 2.2 and 13.3 GHz was firstly designed for the UWB applications. Each square element was fed through a 50-Ω microstrip transmission line (MTL). A thin strip line was designed at the end of MTL to provide impedance matching. Although the isolation level between the elements was satisfactory for efficient MIMO implementation, a T-shaped strip on the ground was employed to further improve the isolation for low frequency. The frequency range of 4.4–6.2 GHz which is an important band of wireless local area network (WLAN) standard was then notched by forming a G-shaped structure on the square element. The performance of G-shaped antenna system was studied in terms of important antenna characteristics and MIMO parameters. The results demonstrate that the G-shaped MIMO antenna has nearly omnidirectional patterns, stable gain and good diversity performance besides having low-profile elements.