Printed Yagi-Uda array for MIMO systems

In this paper, A Yagi-Uda antenna array consisting of four radiating elements is presented. The array elements are oriented back to back in a cross fashion to achieve a pattern orthogonality utilizing the end-fire radiation characteristics of the Yagi-Uda antennas. This technique is proposed to reduce the mutual coupling between the radiating elements which is essential to the performance of Multiple Input Multiple Output (MIMO) systems. Design and simulations are conducted using CST Microwave Studio which is based on the Finite Integration Technique (FIT). Results show that the correlation level is below -35 dB between the array elements at 5.2 GHz with about λ/4 separation distance.