A Novel Approach for Parasitic Decoupling Element Design for MIMO Applications

Mutual coupling is a critical issue in the design of mimo antennas as it deteriorates mimo and diversity system performance. this work presents a novel approach and guideline for the design of a compact parasitic decoupling element between two element mimo antennas. it is based on a stepped impedance resonator circuit theory, where the antenna impedance bandwidth, the level of isolation and compactness can all be controlled and optimized. using this theory, a compact planar inverted-l dual-element antenna with a parasitic decoupling element is proposed for handset terminal applications. measurement results show that this design has a good performance over the frequency range 1700-2700mhz, which covers most of cellular frequency bands, such as dcs 1800, pcs 1900, umts, and lte-advanced between 1700-2700mhz. finally, diversity performance parameters are obtained and evaluated based on both the simulated and measured results.