Compact 4-Port MIMO/Diversity Antenna with Low Correlation for UWB Application

Frequenz ◽  
2018 ◽  
Vol 72 (9-10) ◽  
pp. 429-435 ◽  
Author(s):  
Rohit Mathur ◽  
Santanu Dwari

Abstract A compact four port multiple-input-multiple-output (MIMO) antenna with polarization diversity for ultrawideband (UWB) application is proposed. The antenna contains four monopoles where each monopole has three concentric rings. Orthogonal arrangement of monopoles of the antenna provides good isolation and polarization diversity. The antenna has compact size of 36×36×1.6 mm3. It operates in the frequency band of 3.2 to 11 GHz where isolation is better than 15 dB. The envelop correlation coefficient (ECC) and diversity gain from S-parameter have been calculated to evaluate MIMO performance of the antenna. In addition to ensure distortion less transmission in UWB group delay is also calculated.

Electronics ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 261 ◽  
Author(s):  
Naser Ojaroudi Parchin ◽  
Haleh Jahanbakhsh Basherlou ◽  
Yasir I. A. Al-Yasir ◽  
Ahmed M. Abdulkhaleq ◽  
Mohammad Patwary ◽  
...  

In this study, a new coplanar waveguide (CPW)-fed diversity antenna design is introduced for multiple-input–multiple-output (MIMO) smartphone applications. The diversity antenna is composed of a double-fed CPW-fed antenna with a pair of modified T-ring radiators. The antenna is designed to cover the frequency spectrum of commercial sub-6 GHz 5G communication (3.4–3.8 and 3.8–4.2 GHz). It also provides high isolation, better than −16 dB, without an additional decoupling structure. It offers good potential to be deployed in future smartphones. Therefore, the characteristics and performance of an 8-port 5G smartphone antenna were investigated using four pairs of the proposed diversity antennas. Due to the compact size and also the placement of the elements, the presented CPW-fed smartphone antenna array design occupies a very small part of the smartphone board. Its operation band spans from 3.4 to 4.4 GHz. The simulated results agree well with measured results, and the performance of the smartphone antenna design in the presence of a user is given in this paper as well. The proposed MIMO design provides not only sufficient radiation coverage supporting different sides of the mainboard but also polarization diversity.


Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2688
Author(s):  
Wenfei Yin ◽  
Shaoxiang Chen ◽  
Junjie Chang ◽  
Chunhua Li ◽  
Salam K. Khamas

In the paper, an extremely compact multiple-input-multiple-output (MIMO) antenna is proposed for portable wireless ultrawideband (UWB) applications. The proposed prototype consists of four monopole antenna elements, which are placed perpendicularly to achieve polarization diversity. In addition, the mutual coupling between antenna elements is suppressed by designing the gap between the radiation element and the ground plane. Moreover, a matching stub has been connected to the feedline to ensure impedance matching in high frequency. Both simulated and measured results indicate that the proposed antenna has a bandwidth of 3–20 GHz, with a high isolation better than 17 dB. In addition, the designed MIMO antenna offers excellent radiation characteristics and stable gain over the whole working band. The envelope correlation coefficient (ECC) is less than 0.1, which shows that the antenna can meet the polarization diversity characteristics well.


2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Abubaker Ahmed Elobied ◽  
Xue-Xia Yang ◽  
Ningjie Xie ◽  
Steven Gao

This paper presents a close-spaced dual-band 2 × 2 multiple-input multiple-output (MIMO) antenna with high isolation based on half-mode substrate integrated waveguide (HMSIW). The dual-band operation of the antenna element is achieved by loading a rectangular patch outside the radiating aperture of an HMSIW cavity. The HMSIW cavity is excited by a coaxial probe, whereas the rectangular patch is energized through proximity coupling by the radiating aperture of HMSIW. The antenna elements can be closely placed using the rotation and orthogonal arrangement for a 2 × 2 array. Small neutralization lines at the center of the MIMO antenna can increase the isolation among its elements by around 10 dB in the lower band and 5 dB in the higher band. A prototype of the MIMO antenna is fabricated and its performance is measured. The measured results show that the resonant frequencies are centered at 4.43 and 5.39 GHz with bandwidths of 110 and 80 MHz and peak gains of 6 and 6.4 dBi, respectively. The minimum isolation in both bands is greater than 35 dB. The envelope correlation coefficient is lower than 0.005 within two operating bands.


2016 ◽  
Vol 9 (3) ◽  
pp. 573-580 ◽  
Author(s):  
Garima Srivastava ◽  
B. K. Kanuijia ◽  
Rajeev Paulus

A compact printed 2 × 2 ultrawideband (UWB) multiple input multiple output (MIMO) antenna with a single circular patch as a common radiator for both the antenna elements is presented in this paper. A single circular patch is excited by two tapered CPW feeds for dual polarization. To improve the isolation between two ports, a rectangular slot of dimension L1 × W1 is created in the radiator. The UWB MIMO antenna has impedance bandwidth of 3–12 GHz with a isolation better than 17 dB between the two ports. The envelope correlation coefficient and the capacity loss are evaluated to ensure the good diversity performance of UWB MIMO antenna. The antenna has a compact size of 45 × 45 mm2 and is fabricated on low cost FR4 substrate and measured using Agilent VNA. The simulated and measured results show that the proposed UWB antenna is good candidate for UWB MIMO applications.


2019 ◽  
Vol 16 (10) ◽  
pp. 4242-4248
Author(s):  
Manoj Kapil ◽  
Manish Sharma

In this research article, a compact MIMO (Multiple-Input-Multiple-Output) antenna with inclusion of two notched bands characteristics is presented. Designed MIMO antenna consist of dual radiating patches printed on one surface of the substrate which covers measured wide impedance bandwidth of 2.88 GHz–19.98 GHz and satisfies bandwidth ratio more than 10:1 for superwideband with compact size of 18 mm × 34 mm. Two radiating patch are placed symmetrically for MIMO configuration and notched bands to eliminate WiMAX/C and WLAN bands are obtained by attaching inverted T-shaped stub on radiating patch and etched inverted U-shape slit in microstrip feed. Isolation between the two radiating patch is maintained by adding two L-shaped stub in slotted rectangular ground plane. Measured radiation pattern are stable in operating band and offers maximum 4.23 dBi and 89% gain and radiation efficiency respectively. Moreover, antenna shows good diversity performance with Envelope-Correlation-Coefficient (ECC) < 0.5, Directive-Gain (DG) > 9.95 dB and Total-Active-Reflection Coefficient (TARC) < -30 dB.


2016 ◽  
Vol 9 (5) ◽  
pp. 1147-1153 ◽  
Author(s):  
Ling Wu ◽  
Yingqing Xia

With quad-band-notched characteristic, a compact ultrawideband (UWB) multiple-input-multiple-output (MIMO) antenna is introduced in the paper. The UWB–MIMO system has two similar monopole elements and occupies 30 × 45 mm2. By inserting two L-shaped slots, CSRR and C-shaped stubs, four notched bands are achieved (3.25–3.9, 5.11–5.35, 5.5–6.06, and 7.18–7.88 GHz) to filter WiMAX, lower WLAN, upper WLAN, and X-band. Meanwhile, the isolation is obviously enhanced with three metal strips on the ground plane. Results indicate that the antenna covers UWB frequency band of 3.1 – 10.6 GHz except four rejected bands, isolation of better than −18 dB, envelope correlation coefficient of <0.02, and good radiation pattern, thus making it useful for UWB systems.


Electronics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1307
Author(s):  
Omer Arabi ◽  
Chan Hwang See ◽  
Atta Ullah ◽  
Nazar Ali ◽  
Bo Liu ◽  
...  

A closely packed wideband multiple-input multiple-output (MIMO)/diversity antenna (of two ports) with a small size of less than 18.5 mm by 18.5 mm is proposed for mobile communication applications. The antenna can be orthogonally configured for corner installation or by placing it on a back-to-back structure for compact modules. To enhance the isolation and widen the bandwidth, the antenna is structured with multiple layers having differing dielectric constants. The feeding through a via significantly reduces the ground waves. A multi-fidelity surrogate model-assisted design exploration method is employed to obtain the optimized antenna geometric parameters efficiently. The antenna design was investigated using electromagnetic simulation and a physical realization of the optimal design was then created and subjected to a range of tests. The specific parameters investigated included reflection coefficients, mutual coupling between the input ports, radiation patterns, efficiency and parameters specific to MIMO behavior: envelope correlation coefficient and pattern diversity multiplexing coefficient. It was found that the antenna has an impedance bandwidth of approximately 4 GHz, mutual coupling between input ports of better than −18 dB and an envelope correlation coefficient of less than 0.002 across the operating band. This makes it a good candidate design for many mobile MIMO applications.


Electronics ◽  
2021 ◽  
Vol 10 (23) ◽  
pp. 3031
Author(s):  
Jayshri Kulkarni ◽  
Abdullah G. Alharbi ◽  
Arpan Desai ◽  
Chow-Yen-Desmond Sim ◽  
Ajay Poddar

A single radiator that is a part of four-port diversity Multiple-Input Multiple-Output (MIMO) antenna design is composed of four octagonal rings embedded between the two opposite sides of a T-shaped conductive layer surrounded by inverted angular edge cut L-shaped and E-shaped structures. The radiators are placed at the four corners with common ground at the center of a smartphone to form a four-element mobile MIMO antenna. The printing of the antenna is carried out on the flexible polyamide substrate (dielectric constant = 3.5 and loss tangent = 0.0027) with dimensions of 70 × 145 × 0.2 mm3. A wide impedance bandwidth of (84.12%) 2.39 to 5.86 GHz is achieved for all four radiators. The compact size of the radiators along with their placement enables the proposed MIMO antenna to occupy much less area while preserving the space for 2G/3G/4G antennas. The placement of the antennas results in self-isolation between antenna elements by achieving isolation greater than 17.5 dB in the desired operating bands. Furthermore, besides showing a high efficiency of 85% and adequate gain above 4 dBi, good diversity performances such as Envelope Correlation Coefficient (ECC) of less than 0.05, Diversity Gain (DG) of above 9.8 dB, Mean Effective Gain (MEG) of −3.1 dB, Channel Capacity of 21.50 bps/Hz, and Total Active Reflection Coefficient (TARC) of below −10 dB are achieved by the flexible MIMO smartphone antenna. The effect of bending along the X and Y-axis on the performance of the proposed MIMO antenna is also analyzed where decent performance is observed. This makes the proposed flexible four-element MIMO antenna a potential candidate to be deployed in future smartphones.


2019 ◽  
Vol 8 (3) ◽  
pp. 6-15
Author(s):  
A. Chaabane ◽  
A. Babouri

This paper introduces a novel compact planar Ultra-Wideband (UWB) Multiple-Input-Multiple-Output (MIMO) antenna with dual-band notched performance for Surfaces Penetrating (SP) application. To avoid interference from co-existing systems, two notched bands are introduced by including strips inside the radiating patches. The two ports MIMO antenna is printed on the low-cost FR4 substrate having a compact size of 56×32.47×1.5 mm3. The measured results indicate that the −10 dB bandwidth of the proposed MIMO antenna covers a wide bandwidth from 1.57 GHz to 12.4 GHz (155.05%) with dual-band rejection (2.04 GHz – 3.98 GHz and 4.8 GHz – 6.22 GHz). The effects of numerous construction and decoration surfaces on the antenna’s reflection coefficients are measured. Gypsum, White Portland Cement, Slate, Marble, Wood and Reinforced Concrete were tested. A good penetrating capability is measured which confirms the aptitude of the proposed MIMO antenna to work as SP antenna.


Frequenz ◽  
2018 ◽  
Vol 72 (11-12) ◽  
pp. 503-509
Author(s):  
Rohit Mathur ◽  
Santanu Dwari

Abstract A compact 4-port ultra-wide band (UWB) multiple-input-multiple-output (MIMO) slot antenna with dual polarization is presented. The key features of antenna are: has directive radiation in two planes and low correlation without use of additional decoupling structure. The antenna contains four microstrip feedlines having circular patches backed by stepped circular slots. Orthogonal arrangement of each slot antenna increases compactness with polarization diversity and good isolation. The antenna has compact size of 36×36×0.8 mm3. It operates in the frequency band of 3.1 to 11.9 GHz and isolation is better than 15 dB. The superior diversity performance is ensured by calculating envelope correlation coefficient (ECC) and diversity gain. In addition to guarantee distortion less transmission in UWB group delay is also measured.


Sign in / Sign up

Export Citation Format

Share Document