Designs of Multiple Input Multiple Output Antennas for GSM, LTE, WIMAX and WLAN Standards

Abstract

Data transmitting rate of wireless communication systems has been remarkably increased in recent years owing to the transferring requirements of the enormous data belonging to the multimedia services. Multiple inputs multiple outputs (MIMO) systems have been one of the most significant breakthrough in modern wireless communication due to overcoming the limited channel capacity. A MIMO system is capable of simultaneously transmitting multiple signals through spatially parallel channels between isolated multiple antennas. The MIMO technology has been recently adapted to latest mobile communication standards such as long term evolution (LTE), worldwide interoperability for microwave access (WiMAX) and wireless local area network (WLAN). It is, therefore, necessary to incorporate compact, wideband MIMO antennas with high isolation between antenna elements to mobile terminals. In recent years, MIMO antenna designs vary in geometry, size, bandwidth and isolation are available in the literature. In this study, MIMO antenna designs proposed for wireless handsets in the literature have been reviewed and some highlighted designs are summarized to collect a single resource. It is seen that in designs, two identical and symmetrical antenna elements were generally utilized and antennas were designed by considering the GSM, LTE, WiMAX and WLAN wireless standards. These antenna designs have been compared in terms of their geometries, sizes, supported bands and bandwidth, isolation levels and the techniques used to improve the mutual coupling between antenna elements.

Keywords: Antenna, microstrip antenna, multiple inputs multiple outputs (MIMO), wireless communication systems, mobile handsets