Mutual coupling reduction in wideband tree shaped fractal dielectric resonator antenna array using defected ground structure for MIMO applications

摘要

In this letter, a novel fractal tree shaped two-element dielectric resonator antenna (DRA) design for wideband multiple input multiple output (MIMO) applications is proposed. Fractal tree shaped geometry is proposed to achieve wideband characteristics while a C-shaped periodic defected ground plane structure (PDGS) is used to achieve reduction in mutual coupling between two closely spaced antenna elements. Extensive parametric study is carried out to obtain desired mutual coupling reduction without much affecting the bandwidth of the DRA array. The proposed antenna was fabricated and its performance was tested. Measured impedance bandwidth of around 89.9% (-10dB as reference) is achieved over a frequency band of 3.95-10.4GHz. Measured mutual coupling less than -15dB is obtained over the entire band of interest. Both the measured results are quite in accordance to the simulated results. The antenna design parameters, its associated results and parametric study of antenna parameters are discussed in the paper.