Cordate-shaped UWB-MIMO antenna with notch band characteristic and high isolation

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Preeti Pannu ◽  
Devendra Kumar Sharma

Purpose This paper aims to design a most demanding low profile and compact ultra-wide band (UWB) antenna system for various wireless applications. The performance (in terms of data rate) of UWB system is improved by using multiple-input-multiple-output (MIMO) technology with it. Owing to the overlap of other existing licensed bands with that of UWB, electromagnetic signals can interfere. So, notched band UWB MIMO antenna system reported here which is highly compact, bandwidth efficient, superior data rate and high inter-element isolation comparatively to other reported designs. Design/methodology/approach A 49 × 49 × 1.6 mm3 quad-port UWB MIMO antenna with specific bandwidth elimination property is designed. The proposed planar MIMO configuration comprises unique four identical “Cordate-shaped” monopole radiators fed by 2.3-mm thick microstrip-lines. The radiators are located right-angled to each other to enhance inter-element isolation. Further, a different approach of slitted-substrate is applied to minimize the overall size and mutual coupling of the MIMO antenna, as a substitute of decoupling and matching structures. The defected ground structure is used to obtain −10 dB impedance bandwidth in entire UWB band, without compromising with the lower cut-off frequency response. Further, to eliminate the undesired resonant band (WLAN at 5.5 GHz) from UWB, a rounded split ring resonator is introduced in monopole patch. Findings In the entire operating band of 2.8 to 11 GHz, isolation among elements is more than 24 dB, envelope correlation coefficient less than 0.002, diversity gain greater than 9.99 dB and TARC less than −7 dB are obtained at all 4-ports. Research limitations/implications The measured parameters of the fabricated prototype antenna on FR4 substrate are found in good agreement with the simulated results. The small variation in software results and hardware results are observed due to hardware design limitations. Practical implications The proposed design may be used for any wireless application following in the range of UWB. Originality/value It can be shown from graphs of measured parameters of the fabricated prototype antenna. They found to be in good agreement with the simulated results.

2014 ◽  
Vol 8 (1) ◽  
pp. 117-124 ◽  
Author(s):  
Mohammed Younus Talha ◽  
Kamili Jagadeesh Babu ◽  
Rabah W. Aldhaheri

A novel compact multiple-input–multiple-output (MIMO) antenna system operating from 5 to 7.3 GHz is proposed for wireless applications. It comprises of two similar antennas with microstrip feeding and radiating patches developed on a reduced ground plane. The developed antenna system resonates at a dual-band of 5.4 and 6.8 GHz frequencies, giving an impedance bandwidth of 38% (based on S11 < −10 dB). The unique structure of the proposed MIMO system gives a reduced mutual coupling of −27 dB at 5.4 GHz resonant frequency and −19 dB at 6.8 GHz resonant frequency and in the entire operating band the coupling is maintained well below −16 dB. The envelope correlation coefficient of the proposed MIMO system is calculated and is found to be less than 0.05 in the operating band. The measured and simulation results are found in good agreement.


Electronics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1582
Author(s):  
Ahsan Altaf ◽  
Amjad Iqbal ◽  
Amor Smida ◽  
Jamel Smida ◽  
Ayman A. Althuwayb ◽  
...  

Multiple-input multiple-output (MIMO) scheme refers to the technology where more than one antenna is used for transmitting and receiving the information packets. It enhances the channel capacity without more power. The available space in the modern compact devices is limited and MIMO antenna elements need to be placed closely. The closely spaced antennas undergo an undesirable coupling, which deteriorates the antenna parameters. In this paper, an ultra wide-band (UWB) MIMO antenna system with an improved isolation is presented. The system has a wide bandwidth range from 2–13.7 GHz. The antenna elements are closely placed with an edge to edge distance of 3 mm. In addition to the UWB attribute of the system, the mutual coupling between the antennas is reduced by using slotted stub. The isolation is improved and is below −20 dB within the whole operating range. By introducing the decoupling network, the key performance parameters of the antenna are not affected. The system is designed on an inexpensive and easily available FR-4 substrate. To better understand the working of the proposed system, the equivalent circuit model is also presented. To model the proposed system accurately, different radiating modes and inter-mode coupling is considered and modeled. The EM model, circuit model, and the measured results are in good agreement. Different key performance parameters of the system and the antenna element such as envelope correlation coefficient (ECC), diversity gain, channel capcity loss (CCL) gain, radiation patterns, surface currents, and scattering parameters are presented. State-of-the-art comparison with the recent literature shows that the proposed antenna has minimal dimensions, a large bandwidth, an adequate gain value and a high isolation. It is worth noticeable that the proposed antenna has high isolation even the patches has low edge-to-edge gap (3 mm). Based on its good performance and compact dimensions, the proposed antenna is a suitable choice for high throughput compact UWB transceivers.


2018 ◽  
Vol 11 (3) ◽  
pp. 287-296 ◽  
Author(s):  
Sanjay Chouhan ◽  
Debendra Kumar Panda ◽  
Vivek Singh Kushwah ◽  
Pankaj Kumar Mishra

AbstractA four-element wide-band octagonal ring-shaped antenna is proposed for human interface device and S-band applications. The isolation structure comprises a parasitic element and a T-shaped structure. The antenna has −10 dB impedance bandwidth 63% (2.1–4.0 GHz) with miniaturized dimension of 54.98 mm × 76 mm. The multiple input multiple output (MIMO) antenna gain is 2.83 dBi at the 2.4 GHz resonant frequency. The designed MIMO has envelop correlation coefficient of 0.026 in the 2:1 VSWR band. The −10 dB total active reflection coefficient bandwidth of 1.2 GHz has been achieved in the entire frequency band, and has MEG value of ≤−3 dB. The specific absorption rate has found below the safety limit near the human head, palm and wrist.


Frequenz ◽  
2017 ◽  
Vol 71 (5-6) ◽  
Author(s):  
Lingsheng Yang ◽  
Ming Ji ◽  
Biyu Cheng ◽  
Bo Ni

AbstractIn this letter, an eight-element Multiple-input multiple-output (MIMO) antenna system for LTE mobile handset applications is proposed. The antenna array consists of eight 3D inverted F-shaped antennas (3D-IFA), and the measured –10 dB impedance bandwidth is 3.2–3.9 GHz which can cover the LTE bands 42 and 43 (3.4–3.8 GHz). By controlling the rotation of the antenna elements, no less than 10 dB isolation between antenna elements can be obtained. After using the specially designed meandered slots on the ground as decoupling structures, the measured isolation can be further improved to higher than 13 dB between the antenna elements at the whole operating band.


Electronics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1300
Author(s):  
Daniyal Ali Sehrai ◽  
Muhammad Asif ◽  
Nosherwan Shoaib ◽  
Muhammad Ibrar ◽  
Saeedullah Jan ◽  
...  

This paper presents a multiple-input multiple-output (MIMO) antenna system for millimeter-wave 5G wireless communication services. The proposed MIMO configuration is composed of four antenna elements, where each antenna possesses an HP-shaped configuration that features simple configuration and excellent performance. The proposed MIMO design can operate at a very wideband of 36.83–40.0 GHz (measured). Furthermore, the proposed MIMO antenna attains a peak gain of 6.5 dB with a maximum element-isolation of −45 dB. Apart from this, the MIMO performance metrics such as envelope correlation coefficient (ECC), diversity gain, and channel capacity (CCL) are analyzed, which demonstrate good characteristics across the operating band. The proposed antenna radiates efficiently with a radiation efficiency of above 80% at the desired frequency band which makes it a potential contender for the upcoming communication applications. The proposed design simulations were performed in the computer simulation technology (CST) software, and measured results reveal good agreement with the simulated one.


Author(s):  
D. Rajesh Kumar ◽  
G. Venkat Babu ◽  
K.G. Sujanth Narayan ◽  
N. Raju

Abstract A dual-band 10-port multiple input multiple output (MIMO) antenna array for 5G smartphone is proposed. Each antenna in the MIMO system can work from 3.4 to 3.6 GHz and 5 to 6 GHz with 10 dB (2:1 VSWR) impedance bandwidth. Nevertheless, for a 3:1 VSWR, the antenna operates from 3.3 to 3.8 GHz and 4.67 to 6.24 GHz. The MIMO system is formed by making 10 seven-shaped coupled fed slot antenna elements excited at two different resonant modes and integrated into the system circuit board. By implementing the spatial and polarization diversity techniques, high isolation better than 28 dB between any pair of antenna elements is achieved. The proposed 10-port MIMO antenna array is fabricated and measured. Significant radiation efficiency is obtained, ranging from 65 to 82% for both bands. The antenna gain in the required operating band is substantial, around 3–3.8 dBi. Further, the MIMO parameters such as envelope correlation co-efficient, channel capacity, and total active reflection co-efficient are calculated. The antenna's robustness is estimated by analyzing the user hand effects and specific absorption rate (SAR). The measured results are well agreed with the simulated results.


2021 ◽  
Vol 20 ◽  
pp. 146-151
Author(s):  
Edgar Alejandro Andrade-Gonzalez ◽  
Juan Carlos Ordoñez-Martínez ◽  
Mario Reyes-Ayala ◽  
José Alfredo Tirado Méndez ◽  
Hilario Terres-Peña

In this article, a compact ultra-wide band (UWB) multiple input multiple output (MIMO) antenna system is showed. This antenna is based on fractal Fibonacci circles and operates over wide frequency range from 2.9 to 14.51 GHz. The dielectric used was Duroid substrate with dielectric constant εr = 2.2 and thickness of substrate 1.27 mm. This UWB MIMO antenna is simulated by HFSS. In order to improve the isolation between the elements of the antenna a parasitic structure is used, getting S12 and very low ECC. Also, the Total Active reflection Coefficient (TARC) was obtained. Proposed antenna can be used for UWB communication applications and its size is 64 × 38mm2


Frequenz ◽  
2020 ◽  
Vol 74 (1-2) ◽  
pp. 17-23
Author(s):  
Robert Mark ◽  
Soma Das

AbstractIn this paper, near zero parameter based metamaterial superstrate is presented for mutual coupling reduction in multiple-input-multiple-output (MIMO) antenna. The proposed design offers a peak isolation of 38 dB with edge-separation of 0.042λ0 at resonating frequency. To verify the simulations results, a prototype of the proposed antenna is fabricated and experimentally measured. The two elements MIMO is designed with measured impedance bandwidth of 5.6 to 5.95 GHz with a peak measured gain of 7.4 dBi and efficiency above 95 %.The measurement established an isolation enhancement of 30 dB with minimum correlation coefficient of 0.05 within operating band. The proposed method offers a good design technique for high gain and closely packed MIMO antenna system for WLAN applications.


Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1174 ◽  
Author(s):  
Pawan Kumar ◽  
Shabana Urooj ◽  
Areej Malibari

This article presents a compact, planar, quad-port ultra-wideband (UWB) multiple-input–multiple-output (MIMO) antenna with wide axial ratio bandwidth (ARBW). The proposed MIMO design consists of four identical square-shaped antenna elements, where each element is made up of a circular slotted ground plane and feed by a 50 Ω microstrip line. The circular polarization is achieved using a protruding hexagonal stub from the ground plane. The four elements of the MIMO antenna are placed orthogonally to each other to obtain high inter-element isolation. FR-4 dielectric substrate of size 45 × 45 × 1.6 mm3 is used for the antenna prototype, and a good agreement is noticed among the simulated and experimental results. The proposed MIMO antenna shows 3-dB ARBW of 52% (3.8–6.5 GHz) and impedance bandwidth (S11 ≤ −10 dB) of 144% (2.2–13.5 GHz).


2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Haitham AL-Saif ◽  
Muhammad Usman ◽  
Muhammad Tajammal Chughtai ◽  
Jamal Nasir

This paper presents a novel compact 2 × 2 planar MIMO antenna system with ultra-wide band capability. Antenna system is specifically designed to target lower 5th generation operating bands ranging from 2 GHz to 12 GHz. This band also covers the IEEE 802.11 a/b/g/n/ac. The antenna array geometry has been simulated using CST MWS. The design is extremely miniaturized with total structure size of 13×25×0.254 mm3. The simulated and measured results have been presented. Measured and simulated return loss values for designed antenna are less than −10 dB over the operating band and lowest values of −35 dB and −32.5 dB can been seen at 5.2 GHz and 9.2 GHz, respectively, whereas at the center frequency the return loss is −25.2 dB. The mutual coupling between both elements is less than −20 dB over the transmission bandwidth. Simulated and measured radiation patterns in E and H planes at center frequency show nearly isotropic far fields. The maximum gain is measured as 4.8 dB. Promising results of Envelope Correlation Coefficient and gain diversity of the design have been achieved. Simulated and measured results are found in good agreement. The fractional bandwidth of antenna is measured as 143.2% which satisfies its ultra-wide band response.


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