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123 results on '"Mabrouk, Ismail Ben"'

15. Simultaneous Transmit and Receive Self-Duplexing Antenna for Head Implants

Author

Amjad, Iqbal, Al-Hasan, Muath, Mabrouk, Ismail Ben, Denidni, Tayeb A., Amjad, Iqbal, Al-Hasan, Muath, Mabrouk, Ismail Ben, and Denidni, Tayeb A.

Abstract

A novel dual-port, dual-band self-duplexing implantable antenna for head implants is presented in this article. It operates at 915 MHz Industrial, Scientific, and Medical (ISM) band (when Port 1 is active) and 1420 MHz Wireless Medical Telemetry Service (WMTS) band (when Port2 is active). The proposed antenna is kept inside a flat device and simulated in a human head model. The miniaturization of the proposed antenna is achieved using a high dielectric substrate, shorted pins, and multiple capacitive slots. Consequently, it occupies a compact volume of 7.13 x 8.9 x 0.13 = 8.24 mm(3). The coupling between both radiators is enhanced by printing it on a thin substrate and placing vias between them. As a result, an isolation level better than 31.4 dB is achieved. It has peak realized gains of -18.94 and -17.06 dBi at 915 and 1420 MHz, respectively. The link budget analysis and specific absorption rate (SAR) are performed, showing promising results. The proposed concept is practically validated by measuring its performance inside the minced pork meat. Furthermore, the simultaneous transmit and receive concept is practically verified with the aid of software-defined radio (SDR). The main advantages of this antenna are its compact size, low coupling level, independently controllable bands, and simultaneous transmission and reception of signals without using a multiplexer circuit. © 2023 IEEE.

Published
2023
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16. Deterministic Modeling of MIMO Communication Within Typical Hospital Patient Rooms

Author

Ghaddar, Mohamed, Pascual-Garcia, Juan, Molina-Garcia-Pardo, Jose-Maria, Mabrouk, Ismail Ben, Sun, Hongjian, and Poor, H. Vincent

Abstract

Limited research work has been conducted on deterministic modeling of the fifth-generation wireless communications within hospital patient rooms environment. This letter reports a ray-tracing model algorithm for the prediction of multiple-input–multiple-output (MIMO) propagation in the mm-wave band. The furniture effects are predicted in the framework of uniform theory of diffraction. Each piece of furniture is modeled as a group of perfect conducting wedges of random shape and size. The fixed access point has been configured with two forms of radiation patterns: Directional (D) and Omnidirectional (O). However, the mobile user point, remains O. Results indicate that doubling the number of antennas in a MIMO system operating under O-O configuration leads to a notable boost of 9 bps/Hz in channel capacity. The O-O setup creates a rich multipath environment, favorable for MIMO systems, resulting in an average channel capacity increase of 4 bps/Hz compared with the D-O configuration.

Published
2024
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17. Self-Quadruplexing Antenna for Scalp-Implantable Devices

Author

Iqbal, Amjad, Al-Hasan, Muath, Mabrouk, Ismail Ben, and Denidni, Tayeb A.

Abstract

This article presents a compact self-quadruplexing antenna for scalp-implantable devices. The proposed self-quadruplexing antenna operates at 168 MHz [industrial, scientific, and medical (ISM) band], 433 MHz (ISM band), 915 MHz (ISM band), and 1400 MHz [wireless medical telemetry service (WMTS) band] when Ports 1, 2, 3, and 4 are activated, respectively. The proposed antenna is simulated inside a rectangular device in the head of a human phantom. The suggested antenna comprises four individually excited semicircular meandered resonators with a common ground plane. The compactness of the design is achieved using a high dielectric substrate and using semicircular meandered resonators. The meandered resonators enlarge the current path, resulting in significant miniaturization. As a result, the proposed antenna consumes a small volume of $12\,\, \times 14.5 \times 0.13 = 22.62$ mm3. The coupling among all ports is also minimized using an ultrathin substrate. Consequently, the mutual coupling between any two ports is less than −21.8 dB. It provides a peak gain of −36.24, −34.78, −31.39, and −30.10 dBi at 168, 433, 915, and 1400 MHz, respectively. The link budget and specific absorption rate (SAR) analyses are performed to see the possible applications in the head implant, which show promising results. The 10-g SAR values of 0.017, 0.016, 0.014, and 0.013 W/kg are realized at 168, 433, 915, and 1400 MHz, respectively. Based on a link margin (LM) ≥10 dB, the proposed self-quadruplexing antenna can communicate up to 20, 17.5, 12, and 9 m at 168, 433, 915 and 1400 MHz, respectively (at $B_{r} = 120$ Mbps). Furthermore, the simultaneous transmit and receive (STAR) ability of this antenna is validated using software-defined radios (SDRs). To the best of the authors’ knowledge, this is the first-ever self-quadruplexing implantable antenna designed so far.

Published
2024
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22. 2D MXene Ti₃C₂Tₓ Enhanced Plasmonic Absorption in Metasurface for Terahertz Shielding

Author

Ullah, Zaka, Al Hasanl, Muath, Mabrouk, Ismail Ben, Junaid, Muhammad, Sheikh, Fawad, Al Hasan, Muath, and Ben Mabrouk, Ismail

Subjects
Elektrotechnik
Abstract

With the advancement of technology, shielding for terahertz (THz) electronic and communication equipment is increasingly important. The metamaterial absorption technique is mostly used to shield electromagnetic interference (EMI) in THz sensing technologies. The most widely used THz metamaterial absorbers suffer from their narrowband properties and the involvement of complex fabrication techniques. Materials with multifunctional properties, such as adjustable conductivity, broad bandwidth, high flexibility, and robustness, are driving future development to meet THz shielding applications. In this article, a theoretical simulation approach based on finite difference time domain (FDTD) is utilized to study the absorption and shielding characteristics of a two-dimensional (2D) MXene Ti₃C₂Tₓ metasurface absorber in the THz band. The proposed metamaterial structure is made up of a square-shaped array of MXene that is 50 nm thick and is placed on top of a silicon substrate. The bottom surface of the silicon is metalized with gold to reduce the transmission and ultimately enhance the absorption at 1–3 THz. The symmetric adjacent space between the MXene array results in a widening of bandwidth. The proposed metasurface achieves 96% absorption under normal illumination of the incident source and acquires an average of 25 dB shielding at 1 THz bandwidth, with the peak shielding reaching 65 dB. The results show that 2D MXene-based stacked metasurfaces can be proven in the realization of low-cost devices for THz shielding and sensing applications. CA extern

Published
2023

29. EM-driven size reduction and multi-criterial optimization of broadband circularly-polarized antennas using pareto front traversing and design extrapolation

Author

Ullah, Ubaid, Al-Hasan, Muath, Koziel, Slawomir, and Mabrouk, Ismail Ben

Subjects
Multidisciplinary
Abstract

Maintaining small size has become an important consideration in the design of contemporary antenna structures. In the case of broadband circularly polarized (CP) antennas, miniaturization is a challenging process due to the necessity of simultaneous handling of electrical and field properties (reflection, axial ratio, gain), as well as ensuring sufficient frequency range of operation, especially at the lower edge of the antenna bandwidth. An additional difficulty is that—for the sake of reliability—the design process has to be based on full-wave electromagnetic simulation tools. This is a computationally expensive endeavor because rendering the minimum-size design under the assumed constraints concerning the operating frequencies requires rigorous numerical optimization, which entails massive evaluations of the structure at hand. This paper describes an algorithmic framework for efficient identification of broadband CP antenna designs that realize the best possible trade-offs (Pareto set) between the antenna size and its operating bandwidth. The designs are generated sequentially by solving local optimization tasks targeting explicit reduction of the antenna footprint with implicit constraints imposed on the reflection and axial ratio characteristics. The data accumulated during the previous iterations is employed to yield good initial points for further stages by means of inverse surrogates and extrapolation. Low cost of the process is ensured by sparse sensitivity updates within the trust-region gradient-based algorithm being the main optimization engine. The proposed methodology is demonstrated using three examples of wide-slot CP structures with the trade-off designs representing broad ranges of achievable antenna sizes and operating bandwidth. The framework can be used to assess the antenna suitability for particular application areas as well to conclusively compare alternative CP geometries from the point of view of achievable miniaturization rate and capability of fulfilling given performance requirements.

Published
2021

34. UTD-Based Ray-Tracing MIMO Channel Modeling for the Next-Generation Communications Within Underground Tunnels

Author

Ghaddar, Mohamad, Molina-Garcia-Pardo, Jose-Maria, Mabrouk, Ismail Ben, Lienard, Martine, and Degauque, Pierre

Abstract

Limited work has previously been conducted into deterministic modeling of the fifth generation (5G) millimeter (mm)-wave wireless communications within geometrically nonuniform tunnels. This study predicts and analyzes broadband multiple–input multiple–output (MIMO) propagation in underground mine tunnels for 5G communications and beyond. At extremely short wavelengths, each rugged and uneven surface of the tunnel is modeled as a group of diffracting rectangular prism wedges. A deterministic ray-tracing (RT) MIMO model is developed based on the Uniform Theory of Diffraction (UTD). All predicted MIMO subchannels have been successfully fitted with the experimental measurements. MIMO multipath fading of underground tunnels is found to be lognormally distributed and strongly depends on the tunnel’s size and shape.

Published
2023
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41. Feedforward Neural Network-Based Data Aggregation Scheme for Intrabody Area Nanonetworks.

Author

Javaid, Shumaila, Wu, Zhenqiang, Fahim, Hamza, Mabrouk, Ismail Ben, Al-Hasan, Muath, and Rasheed, Muhammad Babar

Abstract

An intrabody area nanonetwork (intra-BANN) is a set of nanoscale devices, which have outstanding cellular level precision and accuracy for enabling noninvasive healthcare monitoring and disease diagnosis. In this article, we design a novel feedforward neural networks (FFNNs) based data aggregation scheme that integrates the attributes of artificial intelligence to boost the computational intelligence of intra-BANNs for prolonged network lifetime. In the proposed scheme, data division and labeling are performed to transmit detected information using two different types of packets with different sizes to save energy resources and to avoid redundant data transmission. FFNN-based periodic data transmission exploits the fitness function approximation characteristics of FFNN to increase the transmission probability of critical information with minimum energy consumption and delay, whereas our proposed event-driven data transmission also ensures the transmission of high priority data with minimal delay and storage overhead. The detailed evaluation and comparison of our proposed framework with three existing schemes conducted using the Nano-Sim tool highlight that our proposed scheme performs 50%–60% better than state-of-the-art schemes in terms of residual energy, delay, and packet loss. [ABSTRACT FROM AUTHOR]

Published
2022
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