Metamaterial-Based Highly Isolated MIMO Antenna for Portable Wireless Applications

In this paper, a metamaterial structure is presented to lower the mutual coupling between the closely spaced microstrip patch antenna elements. Two elements Multiple Input Multiple Output (MIMO) antenna is closely placed with each other at edge to edge separation of 0.135 λ 0 (7 mm). Isolation improvement of 9 dB is achieved by keeping the metamaterial structure in between the MIMO elements. With the proposed structure, the isolation is achieved around −24.5 dB. Due to low ECC, high gain, low channel capacity loss and very low mutual coupling between elements, the proposed antenna is a good candidate for the MIMO applications. The proposed antenna is fabricated and tested. A reasonable agreement between simulated and measured results is observed

Low-profile dual-band antenna with on-demand beam switching capabilities

In this study, a dual-band pattern-reconfigurable monopole antenna is designed and experimentally validated for Cband satellite communication systems and sensing UWB-radar applications. The proposed antenna has three resonances at 3, 7 and, 8.5 GHz. To incorporate the reconfigurability, two switches are applied in the ground plane to reshape the radiation pattern and focus the radiated power in the desired direction. Thus, the desired beam from the antenna can be obtained by adjusting the states of the switches. The proposed antenna has good impedance matching (S11 < − 10 dB for both operating bands), reasonable gain (>4.1 dBi), and high efficiency (>83%) for all switching states. A good agreement is observed between the simulated and measured results

Low-profile dual-band antenna with ondemand beam switching capabilities

In this study, a dual-band pattern-reconfigurable monopole antenna is designed and experimentally validated for Cband satellite communication systems and sensing UWB-radar applications. The proposed antenna has three resonances at 3, 7 and, 8.5 GHz. To incorporate the reconfigurability, two switches are applied in the ground plane to reshape the radiation pattern and focus the radiated power in the desired direction. Thus, the desired beam from the antenna can be obtained by adjusting the states of the switches. The proposed antenna has good impedance matching (S11 < − 10 dB for both operating bands), reasonable gain (>4.1 dBi), and high efficiency (>83%) for all switching states. A good agreement is observed between the simulated and measured results

Dielectric resonator antenna with top loaded parasitic strip elements for dual‐band operation

In this article, a dual-band hybrid cylindrical dielectric resonator antenna (CDRA) is designed, analyzed, and experimentally validated. Miniaturization and dual-band frequency behavior are achieved by loading circular copper strips on top of the CDRA. Hence, the antenna resonates at 4.4 and 6.1 GHz covering −10 dB bandwidths of 600 MHz and 500 MHz, respectively. The proposed CDRA is excited using a rectangular slot for HEMY11 and HEMX11 modes. The proposed antenna demonstrates good gain (4.9 dBi at 4.4 GHz and 5.6 dBi at 6.1 GHz), high efficiency (>88% for all operating bands), and good FTBR (>10.08 dB in both principal planes for both operating bands). Moreover, the higher frequency band can be independently controlled by adjusting the parasitic strips width (d) and gap (g)

Dielectric resonator antenna with top loaded parasitic strip elements for dual-band operation

In this article, a dual-band hybrid cylindrical dielectric resonator antenna (CDRA) is designed, analyzed, and experimentally validated. Miniaturization and dual-band frequency behavior are achieved by loading circular copper strips on top of the CDRA. Hence, the antenna resonates at 4.4 and 6.1 GHz covering −10 dB bandwidths of 600 MHz and 500 MHz, respectively. The proposed CDRA is excited using a rectangular slot for HEMY11 and HEMX11 modes. The proposed antenna demonstrates good gain (4.9 dBi at 4.4 GHz and 5.6 dBi at 6.1 GHz), high efficiency (>88% for all operating bands), and good FTBR (>10.08 dB in both principal planes for both operating bands). Moreover, the higher frequency band can be independently controlled by adjusting the parasitic strips width (d) and gap (g)

Design and efficiency enhancement of FTO/PC60BM/CsSn0.5Ge0.5I3/Spiro-OMeTAD/Au perovskite solar cell utilizing SCAPS-1D Simulator

The poisoning potential of lead, which is the main component of the absorber layer of lead halide (Pb) perovskites, as well as the stability problems of the manufactured devices, constitute a major obstacle to the industrialization of this technology. As a result, recent research is concentrating on lead-free metal halide perovskites. Unfortunately, current lead-free perovskites suffer from poor performance, hence the interest of our study. The research presented here shows that optimizing several variables related to the performance of each layer of a perovskite solar cell (PSC) constructed from lead-free inorganic materials provides an efficiency of 18.13%. We designed a structure with outstanding performance using the FTO/PC _60 BM/CsSn _0.5 Ge _0.5 I _3 /Spiro-OMeTAD/Au configuration. The impact of various relevant factors, such as the thickness and defect density of the absorber layer their doping densities, the back contact work, and the operating temperature, have been thoroughly investigated to boost the performance of the proposed device. The performance of cesium-tin-germanium triiodide (CsSn _0.5 Ge _0.5 I _3 ) solar cells with different electron transport materials, including ZnO, TiO _2 , CdS, C _60 ; Cd _0.5 Zn _0.5 S, IGZO, has also been examined. It has been demonstrated that using ZnO as an electron transport layer improves electron extraction and, therefore, performance. The best outcomes are obtained after optimizing all the factors mentioned above, namely: Jsc of 28.70 mA/cm ^2 , Voc of 1.115 V, FF of 87.86%, and PCE of 18.13%. Additionally, the explored structure may be an excellent candidate for the future development of lead-free perovskite solar cells

A dual-band case-printed planar inverted-F antenna design with independent resonance control for wearable short range telemetric systems

In this article, a novel 3D meandered planar inverted-F antenna (PIFA) is proposed for dual band application targeting Wireless Body Area Network (WBAN). The proposed antenna is printed on the casing of a 3D-base-station model having a size of 88 × 95 × 10.2 mm3. The proposed PIFA covers two bands including medical implant communication service (MICS) (402-405 MHz), as well as the industrial, scientific, and medical (ISM) (2.4-2.48 GHz) bands. Each of the two bands can be controlled independently. The 3D configuration contains two linked meandered resonators to downsize the structure. Due to its conformal shape, omnidirectional radiation pattern, and low-profile nature, the proposed PIFA is a potential candidate for targeting the WBAN applications. The proposed antenna, covering the MICS and ISM bands, works with an optimally matching (VSWR<2) at the aforementioned bands. The design concept was validated by fabricating the antenna prototype and measuring its characteristics

Growth and efficiency of MAPbBr3 based perovskite solar cells: insight from experimental and simulation

[EN] Herein, we investigated methylammonium lead bromide (MAPbBr(3)) perovskite materials obtained using a cost-effective spin-coating technique. An important step toward the excellent production of perovskite thin films is antisolvent treatment. The influence of thermal annealing and two different antisolvents (toluene and chlorobenzene) treatments have been studied on the phase formation and microstructure of the perovskite films using X-ray diffraction analysis, SEM, UV-visible, and photoluminescence. The findings reveal that using the appropriate antisolvent resulted in the formation of homogenous perovskite films with almost no holes and large grains and also improved the morphology of the thin film with antisolvents. Subsequently, we analyzed the results to study the characteristics of different perovskite solar cells (PSCs) produced by different antisolvent using a solar cell capacity simulator (SCAPS). The thickness, defect and acceptor densities were optimized. It is found that an optimal thickness of 500 nm has a detrimental effect on the PSC' s performance. Indeed, better results were obtained: fill factor FF = 93.02%, Jsc = 8.87 mA/cm(2), PCE = 17.42%, and Voc = 2.10 V of MAPbBr(3)-based solar cells where MAPbBr(3) treated by Chlorobenzene Fresh. The use of chlorobenzene antisolvent showed an enhancement of the perovskite solar cell' s efficiency. The findings may be of interest to serve in the development of reproducible production procedures of PSCs.The authors thankfully acknowledge Dr. Marc Burgelman, University of Gent, Belgium, for providing the SCAPS simulation software.The author Amal Bouich acknowledges MCIN for funding support through Margarita Salas Fellowship (MCIN/AEI/10.13039/501100011033) and NextGenerationEU.Bouazizi, S.; Bouich, A.; Tlili, W.; Kadri, B.; Amlouk, M.; Omri, A.; Marí, B. (2024). Growth and efficiency of MAPbBr3 based perovskite solar cells: insight from experimental and simulation. Indian Journal of Physics. https://doi.org/10.1007/s12648-023-03065-