A tiny EBG‐based structure multiband MIMO antenna with high isolation for LTE/WLAN and C/X bands applications

Abstract

This article proposes a compact multiple-input multiple-output (MIMO) antenna with the electromagnetic band gap (EBG) structures for mobile terminals. The proposed MIMO antenna is composed of two radiation patches in which diagonal and folded microstrip lines are utilized to control the frequency bands. The radiation patch, one EBG structure and a rectangular-shaped ground plane are etched on both sides of the antenna. The EBG structures have been employed for reducing the mutual coupling between the antenna elements. As a result of the effect of these structures, the mutual coupling between the two elements is reduced by less than −30 dB. The proposed antenna is implemented on an FR4 substrate with dimensions 20 × 10 × 1 mm 3 . According to measured results, frequency ranges of 2.2 to 3.6 GHz and 5.1 to 5.9 GHz with S 11 < −10 dB and also 3.7 to 5 GHz and 8 to 12 GHz with S 22 < −10 dB have been obtained. Moreover, measured S 12 and S 21 with values of less than −30 dB for both Ports have been realized. Additionally, the envelope correlation and radiation efficiency of the purposed antenna are less than 0.09 and more than 82%, respectively. K E Y W O R D S EBG, LTE, MIMO antenna, WLAN

A Comparative Study of Compact Multiband Bio-Inspired Asymmetric Microstrip Fed Antennas (BioAs-MPAs) for Wireless Applications

“…Furthermore, the authors in [11,12] have used electromagnetic Band Gap (EBG) and meandering to realize compact multiband antennas. Parasitic loading has also been used by authors in [13][14][15] for multiband antenna realization.…”

A Compact MIMO Antenna for UWB Applications

“…The 9x1 periodic metal patches (2 mm  2 mm) on top of the substrate connected with a 0.7mm width microstrip, has vertical viases connecting the square patches to the ground plane. The purpose of connected the decoupling structure to the ground is to neutralize the surface current and increase the gain of the antenna [17].…”

“…The MIMO antenna proposed in [17] has two radiation patches with an EBG structure between the elements and a rectangular ground plane. The effect of implementing an EBG structure is a reduction of mutual coupling up to -30 dB, in the frequency band 2.2 to 3.6 GHz and 5.5 to 5.9 GHz.…”

A wideband self‐decoupled multi‐input multi‐output antenna with a high isolation

“…To improve the isolation between antenna elements in MIMO system, tremendous research efforts have been devoted in recent years. 4 Some researches include neutralization line between two coupled antennas, 5,6 parasitic element, 7,8 electromagnetic band gap (EBG) structure, 9 defected ground structure (DGS) [10][11][12] , ground decoupling branches, 13,14 and polarization diversity structure. 15,16 Most of the above designs require the introduction of additional decoupling structures between the coupled antennas.…”