volume | PIER Journals

Abstract

This article describes a four-element ultra-wideband (UWB) Multiple-Input Multiple-Output (MIMO) antenna for the Sub-7 GHz. The antenna element is an elliptical patch slot antenna with a coplanar waveguide (CPW) feed. To make the bandwidth wider, we add step-by-step parasitic stubs based on the results of the Characteristic Mode Analysis (CMA) analysis, which can control multiple modes better. The four-element antenna is connected to a common ground structure with a central cross-shaped isolation stub and also inhibit the propagation of surface waves. It can be used in the range from 1.08 GHz to 8.70 GHz (155.8%), which is fabricated on a low-cost FR4 substrate. In this range, the isolation between antenna elements exceeds 20 dB. The performance of the design is very good. The envelope correlation coefficient (ECC) is less than 0.02, and the diversity gain (DG) is greater than 9.96.

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Professor Chengzhu Du

Dr. Xingyu Liu

Dr. Jiaxuan Tian

Dr. Zhiyuan Wang