Multi-band Planar Inverted-F Antennas for MIMO mobile terminals

Multiple-input multiple-output (MIMO) systems have widely been studied in recent years as a solution to improve the radio link reliability. In order to introduce MIMO in mobile communications, it is necessary to design antennas with several features to let multiple elements in the space reserved for the antenna, such as the type of element or array configuration. In this paper, a 2 x 2 MIMO system has been considered regarding the next-generation WLAN (802.11n). Two dual-band Planar Inverted-F Antennas (PIFAs) for laptop have been design for WLAN bands and two PIFAs for GSM and WLAN bands (1800/2400/5200 MHz) have been designed for a PDA terminal. This type of antenna has been chosen regarding the small space in user terminals. The results have been taken into account to obtain the MIMO channel capacity including radiation pattern and mutual coupling, depending on the employed configuration.