Compact UWB MIMO antenna with pattern diversity and band rejection characteristics

Abstract

This article presents a compact size asymmetric CPW strip‐fed UWB two‐element MIMO antenna, with notched‐band behavior. The single‐antenna element of the MIMO configuration is composed of a semi‐elliptical patch radiator with asymmetric ground plane. The notched‐band behavior of the proposed antenna is achieved by inserting a simple folded stub to the patch radiator. This stub achieves the desired single stop‐band from 3.3 to 3.9 GHz for WIMAX. The two‐antenna elements are placed orthogonally to achieve pattern diversity which leads to an improved MIMO system performance and enhances the isolation between elements without using any decoupling structures. The antenna has dimensions of 50 × 28 mm2. The edge‐to‐edge distance between antenna elements is 0.15λ0 at 3 GHz. The proposed antenna is designed, simulated, fabricated, and tested. Results show that the two‐antenna elements operate at frequencies ranging from 2.8 to 11.5 GHz with return loss lower than −10 dB and insertion loss lower than −18 dB. The performance of the MIMO antenna diversity characteristics were verified through the calculation of the standard parameters and show the antenna suitability for MIMO systems. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1460–1464, 2017

Inner Tapered Tree-Shaped Ultra-Wideband Fractal Antenna with Polarization Diversity

“…An UWB system with polarization diversity technique has potential applications in advanced instruments used for microwave imaging, radar and high-speed data transfer. Some UWB polarization diversity antennas are already reported in the literature [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. However, the application of those available structures is limited due to their large dimensions, multilayer structure, complex feedline, complex geometries, etc.…”

A Compact Quad-Element UWB-MIMO Antenna System with Parasitic Decoupling Mechanism

“…The literature reports extensive research work on UWB-MIMO antennas [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. A four-element UWB-MIMO antenna for portable wireless applications is reported in [14].…”

“…This system achieves isolation of 10 dB in limited frequency band of 1.77 GHz-2.51 GHz. Another semi-elliptical two-element UWB-MIMO antenna is reported in [27]. This design has larger size along with the isolation level of 18 dB.…”

Four-Element MIMO Antenna System for UWB Applications

“…For UWB-MIMO system, how to maintain acceptable isolation (no less than 10 dB) between antenna elements through the wide operational band is a challenging task. Many researches has been reported recently [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Twoelement MIMO antenna system is reported in [5], without using common ground and separate the two elements about 0.37 0 from each other, no less than 15 dB isolation can be realized.…”

“…Polarization diversity is also an effective way in obtaining lower mutual coupling between antenna elements. In [10][11][12][13][14][15][16][17][18], antenna elements are placed perpendicular to each other to exploit polarization diversity and achieve high isolation. While in [19], polarization diversity between leaf-shaped slot antenna and similar shaped monopole is used to obtain good isolation in UWB high band (7.25-10.25 GHz).…”