Combination of tunable printed monopole and elliptical monopole antennas in MIMO configurations for cell phone application

Frequency tunable printed monopole antennas in combination with a quasi-elliptical monopole antenna (EPMA) are presented in multiple inputs multiple output (MIMO) configurations on a cell phone size ground plane. Printed tunable monopole antenna covers long term evolution (LTE) band between 700MHz to 900MHz with 20 MHz flexible bandwidths. The quasi-elliptical planar monopole antenna (EPMA)covers 1.7 GHz to 5.75 GHz wireless communication bands and the structure is fully planar in nature. The antenna has been fabricated and experimentally tested for the S-parameters and radiation performance. The simulated and measured radiation pattern in horizontal plane shows the nearly omni-directional coverage by the antenna. Further, based on the simulated and measured results, the envelope co-relation coefficient (ECC), one of the important parameter of MIMO antenna is investigated. The result shows that it is in the prescribed limit≤0.3 for LTE bandwhich makes it suitable for the cell-phone applications.