Compact UWB-MIMO Antenna With High Isolation and Triple Band-Notched Characteristics

Abstract

A novel and high-performance four-element ultra-wideband (UWB) multiple-input multipleoutput (MIMO) antenna is proposed in the paper. The proposed antenna is designed by using a novel integration technology of the symmetric layout, orthogonal structure, four-directional staircase-shaped decoupling, and multi-slit and multi-slot techniques. The mutual couplings among the antenna elements are significantly reduced by introducing the symmetric orthogonal and separated four-directional staircaseshaped structure. Furthermore, the antenna size is effectively miniaturized, and its impedance bandwidth is broadened by using a two-sided symmetric layout, partial and defected ground structure, the decoupling structure, and multi-slot and multi-slit techniques. Therefore, the antenna has the low-profile structure and a small dimension of 39mm×39mm×1.6mm. Moreover, the proposed antenna achieves triple band-notched characteristics by embedding different type slots and slits on the square radiating elements, default ground structure, and the decoupling structure, respectively. As a result, the antenna obtains the wider bandwidth of 2.30-13.75 GHz with the notched bands of 3.25-3.75 GHz, 5.08-5.90 GHz, and 7.06-7.95 GHz. The three notched bands are good in agreement with the existing interference bands of WiMAX (3.3-3.7 GHz), , and X-band (7.1-7.9 GHz), respectively. In addition, the proposed antenna also has a lower mutual coupling (<−22dB), lower envelop correlation coefficient (ECC<0.02, except for the three notched bands), high multiplexing efficiency (η mux >−3.0dB), stable gain, and quasi-omnidirectional radiation patterns at the entire impedance bandwidth. Therefore, a good tradeoff of the performance is obtained for the proposed antenna. The proposed antenna can be a good candidate for UWB-MIMO wireless communication applications, and especially for portable UWB-MIMO systems.INDEX TERMS UWB-MIMO antenna, symmetric orthogonal structure, multi-slot-multi-slit, high isolation, triple band-notched characteristics. I. INTRODUCTION

Neutralization Line Decoupling Tri-Band Multiple-Input Multiple-Output Antenna Design

“…The lower the mutual coupling is, the higher the DG is and vice versa. The method of using the ECC to calculate DG is given by using the equation as follows [20].…”

Design of MIMO antenna to interference inherent for ultra wide band systems using defected ground structure

“…A Tee crossed structure diversity antenna with microstrip fed having a 32.6 × 46 ranges 1.8 to 12 GHz with S 21 < −15 dB observed and ECC is less than 0.2 observed in Reference . A compact UWB structure MIMO antenna occupied by 39 × 39 mm 2 ranging from 2.3 to 13.75 GHz produced a gain of 4.6 dBi observed in Reference . A compact structure of 40 × 40 mm designed antenna ranging from 3.18– to 11.50 GHz having an efficiency more than 85% at the resonant band of frequencies mentioned in Reference produced isolation greater than −30 dB.…”

A Super-Wideband and High Isolation MIMO Antenna System Using a Windmill-Shaped Decoupling Structure

“…Both presented in [12], [13] require a relatively complex manufacturing process. Differently, a separated staircase-shaped structure to reduce coupling was introduced in [14], and the designed UWB-MIMO antenna with four elements could perform well in miniaturization and high isolation. Koch fractal geometry was employed to achieve desired miniaturization and wideband phenomena for the designed UWB-MIMO antenna fabricated on the FR4 substrate in [15].…”