x3 Scale-model experiments on a slot-based directivity control built-in antenna sytem for mobile terminals

In the field of mobile communication, the used of Multiple-input Multiple-output (MIMO) systems to increase channel capacity has received increasing attention in recent years. In these systems, antennas play an important role, since antenna's radiation characteristics are inherently included in the communication channel between the transmitter and the receiver. Especially, the increased mutual coupling between built-in antennas will affect the radiation efficiency and correlation of the antennas. To reduce mutual coupling and correlation between antennas, element-separation of more than half wavelength is required [1]. However, small sized terminals will often be required in real applications and limited space makes element-separation difficult to achieve.