Mai O. Sallam
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Mai O. Sallam has a total of 16 co-authors. Here are the top co-authors by number of shared publications:
- Ezzeldin A. Soliman
Physics Department, School of Sciences and Engineering, The American University in Cairo, New Cairo, Egypt
4 shared publications - Guy A. E. Vandenbosch
Department of Electrical Engineering (ESAT), KU Leuven, Leuven, Belgium
3 shared publications - Mohamed M. Gad
Nanoelectronics Integrated Systems Center, School of Engineering and Applied Sciences, Nile University, Giza 12588, Egypt
2 shared publications - Allam M. Ameen
Microstrip Department, Electronics Research Institute, New Nozha, Cairo, Egypt
1 shared publication Ezzeldin A. Soliman
Physics Department, School of Sciences and Engineering, The American University in Cairo, New Cairo, Egypt
1 shared publicationGeorges Gielen
ESAT-TELEMIC, Katholieke Universteit Leuven, B-3001-Leuven, Belgium
1 shared publication
Latest Publications
- Open Access
Ultra-Thin Compact Bidirectional S-Slot Antenna for 5G Communications
A compact and low-profile S-slot antenna for millimeter-wave wireless communication applications is presented in this paper. The antenna employs an S-shaped slot etched within a ground plane and excited by a hook-shaped microstrip feeding line to radiate a linearly polarized wave with a bidirectional broadside radiation beam. The antenna geometrical parameters are optimized to cover the n257 and n261 5G bands of the 5G mobile communications. The proposed antenna is fabricated and measured. Simulated and measured results demonstrate good impedance matching, with a measured fractional bandwidth of 18.3% and a maximum realized gain of 4.8 dBi across the desired operating bandwidth for the S-slot antenna with extended ground plane necessary for the purpose of measurements. The performance remains largely unaffected when the ground plane is reduced, highlighting the antenna’s suitability for compact implementations. Consequently, the proposed antenna is well suited for indoor 5G small-cell deployments and future railway wireless communication systems. Moreover, it can serve as a unit element in MIMO arrays or larger antenna configurations. To further demonstrate scalability and system-level applicability, the antenna element is extended into a compact eight-element MIMO array providing dual linear polarization. The array exhibits low mutual coupling, an envelope correlation coefficient on the order of , and a diversity gain approaching 10 dB. These results demonstrate highly independent radiation characteristics and reliable MIMO performance in multipath environments.Open AccessUltra-Thin Compact Bidirectional S-Slot Antenna for 5G Communications
A compact and low-profile S-slot antenna for millimeter-wave wireless communication applications is presented in this paper. The antenna employs an S-shaped slot etched within a ground plane and excited by a hook-shaped microstrip feeding line to radiate a linearly polarized wave with a bidirectional broadside radiation beam. The antenna geometrical parameters are optimized to cover the n257 and n261 5G bands of the 5G mobile communications. The proposed antenna is fabricated and measured. Simulated and measured results demonstrate good impedance matching, with a measured fractional bandwidth of 18.3% and a maximum realized gain of 4.8 dBi across the desired operating bandwidth for the S-slot antenna with extended ground plane necessary for the purpose of measurements. The performance remains largely unaffected when the ground plane is reduced, highlighting the antenna’s suitability for compact implementations. Consequently, the proposed antenna is well suited for indoor 5G small-cell deployments and future railway wireless communication systems. Moreover, it can serve as a unit element in MIMO arrays or larger antenna configurations. To further demonstrate scalability and system-level applicability, the antenna element is extended into a compact eight-element MIMO array providing dual linear polarization. The array exhibits low mutual coupling, an envelope correlation coefficient on the order of , and a diversity gain approaching 10 dB. These results demonstrate highly independent radiation characteristics and reliable MIMO performance in multipath environments. - Open Access
- 24 October 2024
- Published by Springer Nature in Optical and Quantum Electronics
- Vol. 56 (11) , 1-13
Particle swarm optimization of high Q factor interdigitated E-shaped metamaterial for refractive index sensing
Metamaterials for refractive index sensing applications have garnered significant attention in recent years. However, achieving an optimal balance between high sensitivity and quality factor, which together determine the Figure of Merit of sensors, necessitates extensive optimization efforts. In this paper, we present the metaheuristic optimization of a refractive index-based plasmonic sensor operating at a wavelength of 1500 nm, which has the potential to open new avenues for applications in biomedical sensing and beyond. Particle Swarm Optimization is utilized to maximize the performance of the proposed infrared metamaterial sensor. The proposed design features two overlapping E-shaped silver patches placed on top of a grounded $$\mathrm {Al_{2}O_{3}}$$ substrate. This configuration results in a narrow-band absorption spectrum with peak resonances caused by the confinement of the electric field within the gaps of the E-shaped metallic arms. The metaheuristic optimization process yielded sensor dimensions that achieve a high sensitivity of 834.7 nm/RIU,Q = 865 and a Figure of Merit of 481.34 $$\textrm{RIU}^{-1}$$ , demonstrating outstanding performance in cancer cell detection.- 24 October 2024
- Published by Springer Nature in Optical and Quantum Electronics
- Vol. 56 (11) , 1-13
Open AccessParticle swarm optimization of high Q factor interdigitated E-shaped metamaterial for refractive index sensing
Metamaterials for refractive index sensing applications have garnered significant attention in recent years. However, achieving an optimal balance between high sensitivity and quality factor, which together determine the Figure of Merit of sensors, necessitates extensive optimization efforts. In this paper, we present the metaheuristic optimization of a refractive index-based plasmonic sensor operating at a wavelength of 1500 nm, which has the potential to open new avenues for applications in biomedical sensing and beyond. Particle Swarm Optimization is utilized to maximize the performance of the proposed infrared metamaterial sensor. The proposed design features two overlapping E-shaped silver patches placed on top of a grounded $$\mathrm {Al_{2}O_{3}}$$ substrate. This configuration results in a narrow-band absorption spectrum with peak resonances caused by the confinement of the electric field within the gaps of the E-shaped metallic arms. The metaheuristic optimization process yielded sensor dimensions that achieve a high sensitivity of 834.7 nm/RIU,Q = 865 and a Figure of Merit of 481.34 $$\textrm{RIU}^{-1}$$ , demonstrating outstanding performance in cancer cell detection. - Open Access
- 8 March 2024
- Published by Springer Nature in Scientific Reports
- Vol. 14 (1) , 1-12
High gain antipodal meander line antenna for point-to-point WLAN/WiMAX applications
This paper introduces a planar antipodal meander line antenna fabricated using RO3003 substrate. The proposed antenna is designed to radiate in the end-fire direction, achieving a maximum measured gain of 10.43 dBi within its working bandwidth, which ranges from 2.24 GHz to 2.7 GHz, covering long-range WLAN/WiMAX applications. A systematic procedure is adopted in the design process to prove its tunability to cover other application requirements in terms of gain and bandwidth. The proposed design steps show that the bandwidth and the gain can independently be controlled by adjusting specific design parameters such as the number of radiators and the scaling factor. The antenna is fine-tuned using sensitivity analysis and parametric study to guarantee optimum operation at the desired bandwidth. Experimental measurements of the fabricated design demonstrate a high degree of correlation with simulations conducted using CST and HFSS. In comparison to other end-fire antennas presented in the literature, the proposed design manifests its capability to provide high gain for WLAN/WiMAX nodes connectivity. The measurements show that the proposed traveling wave antenna exhibits a high radiation efficiency with maximum value of 99.8% at 2.35 GHz. The measured side lobe level is found to be below $$-18$$ dB and $$-20$$ dB at 2.45 GHz along the $$E$$ - and $$H$$ -planes, respectively. Apart from its excellent radiation performance, the antenna is characterized by its low profile and fabrication simplicity.- 8 March 2024
- Published by Springer Nature in Scientific Reports
- Vol. 14 (1) , 1-12
Open AccessHigh gain antipodal meander line antenna for point-to-point WLAN/WiMAX applications
This paper introduces a planar antipodal meander line antenna fabricated using RO3003 substrate. The proposed antenna is designed to radiate in the end-fire direction, achieving a maximum measured gain of 10.43 dBi within its working bandwidth, which ranges from 2.24 GHz to 2.7 GHz, covering long-range WLAN/WiMAX applications. A systematic procedure is adopted in the design process to prove its tunability to cover other application requirements in terms of gain and bandwidth. The proposed design steps show that the bandwidth and the gain can independently be controlled by adjusting specific design parameters such as the number of radiators and the scaling factor. The antenna is fine-tuned using sensitivity analysis and parametric study to guarantee optimum operation at the desired bandwidth. Experimental measurements of the fabricated design demonstrate a high degree of correlation with simulations conducted using CST and HFSS. In comparison to other end-fire antennas presented in the literature, the proposed design manifests its capability to provide high gain for WLAN/WiMAX nodes connectivity. The measurements show that the proposed traveling wave antenna exhibits a high radiation efficiency with maximum value of 99.8% at 2.35 GHz. The measured side lobe level is found to be below $$-18$$ dB and $$-20$$ dB at 2.45 GHz along the $$E$$ - and $$H$$ -planes, respectively. Apart from its excellent radiation performance, the antenna is characterized by its low profile and fabrication simplicity. - Open Access
- 5 July 2022
- Published by Springer Nature in Research Square
Ultrasensitive E-Shaped Metamaterial Terahertz Biomedical Sensor
This paper develops and evaluates a new topology of a planar metamaterial terahertz sensor. The sensor is constructed by overlapping two E-shaped gold patches placed on top of a grounded dielectric substrate. The absorption spectrum includes peak resonances as a result of the electric field being contained within the gaps between the metallic arms. Two geometrical configurations of the proposed structure are presented and compared. The first configuration realizes a perfect overlap between the horizontal arms of the two E-patches. Almost absorption of (98%) occurs at 5.74 THz with an average sensitivity of 2.8 THz/RIU and a quality factor of 11.39, when the analyte refractive index is varied in the range between n = 1 to n = 1.4. The overlapping distance between the metallic arms is minimized for the second configuration. Therefore, the electric field is more localized within the small gap created between the overlapped arms of the two E-patches. The absorption, sensitivity, and quality factor of the modified structure are 96%, 2.7 THz/RIU, and 27, respectively. The new structure has a notable enhancement in the quality factor while the absorption level and the sensitivity are barely affected.
- 5 July 2022
- Published by Springer Nature in Research Square
Open AccessUltrasensitive E-Shaped Metamaterial Terahertz Biomedical Sensor
This paper develops and evaluates a new topology of a planar metamaterial terahertz sensor. The sensor is constructed by overlapping two E-shaped gold patches placed on top of a grounded dielectric substrate. The absorption spectrum includes peak resonances as a result of the electric field being contained within the gaps between the metallic arms. Two geometrical configurations of the proposed structure are presented and compared. The first configuration realizes a perfect overlap between the horizontal arms of the two E-patches. Almost absorption of (98%) occurs at 5.74 THz with an average sensitivity of 2.8 THz/RIU and a quality factor of 11.39, when the analyte refractive index is varied in the range between n = 1 to n = 1.4. The overlapping distance between the metallic arms is minimized for the second configuration. Therefore, the electric field is more localized within the small gap created between the overlapped arms of the two E-patches. The absorption, sensitivity, and quality factor of the modified structure are 96%, 2.7 THz/RIU, and 27, respectively. The new structure has a notable enhancement in the quality factor while the absorption level and the sensitivity are barely affected.
- 1 December 2018
- Published by Elsevier in Computer Physics Communications
- Vol. 233, 1-15
Generalized mode solver for plasmonic transmission lines embedded in layered media based on the Method of Moments
- 1 December 2018
- Published by Elsevier in Computer Physics Communications
- Vol. 233, 1-15
Generalized mode solver for plasmonic transmission lines embedded in layered media based on the Method of Moments
- 13 September 2017
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Journal of Lightwave Technology
- Vol. 35 (21) , 4700-4706
Novel Wire-Grid Nano-Antenna Array With Circularly Polarized Radiation for Wireless Optical Communication Systems
A new circularly polarized wire-grid nano-antenna array designed for optical telecommunication applications is proposed in this paper. The array consists of two groups of radiators, which are orthogonal to each other. Each group consists of six aligned radiators connected via nonradiating connectors. A 90° phase shift is achieved by inserting a gap between the feeding coupling rods and the inner radiators of one of the two antenna groups. The antenna is characterized by its high directivity (10.8 dBi) and a wide axial ratio bandwidth, which covers the range from 188.2 to 197.8 THz. The radiation efficiency of the antenna is 82.75% at 193.55 THz with very small variations along its operating bandwidth. Such good radiation characteristics are very attractive for optical communication applications.
- 13 September 2017
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Journal of Lightwave Technology
- Vol. 35 (21) , 4700-4706
Novel Wire-Grid Nano-Antenna Array With Circularly Polarized Radiation for Wireless Optical Communication Systems
A new circularly polarized wire-grid nano-antenna array designed for optical telecommunication applications is proposed in this paper. The array consists of two groups of radiators, which are orthogonal to each other. Each group consists of six aligned radiators connected via nonradiating connectors. A 90° phase shift is achieved by inserting a gap between the feeding coupling rods and the inner radiators of one of the two antenna groups. The antenna is characterized by its high directivity (10.8 dBi) and a wide axial ratio bandwidth, which covers the range from 188.2 to 197.8 THz. The radiation efficiency of the antenna is 82.75% at 193.55 THz with very small variations along its operating bandwidth. Such good radiation characteristics are very attractive for optical communication applications.
- 31 May 2017
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Antennas and Propagation
- Vol. 65 (8) , 4274-4277
Wideband CPW-Fed Flexible Bow-Tie Slot Antenna for WLAN/WiMax Systems
A bow-tie antenna based on a slot configuration in a single metal sheet on top of a very thin flexible substrate is introduced. The antenna is constructed from two slotted right-angle triangles fed by a coplanar waveguide transmission line. The topology is very simple and extremely easy to tune in order to reach the proper characteristics after mounting on a supporting structure. A prototype is designed, fabricated, and characterized experimentally. The tunability is proven by considering both the version in free space and the version for use on a brick wall. Measurements demonstrate good agreement with simulations. Both versions cover the wireless local area network (2.4 and 3.65 GHz) and WiMax (2.3, 2.5, and 3.5 GHz) spectra, with an overall impedance bandwidth of 1.79 GHz (57.7%) and 1.46 GHz (49.7%), respectively. The radiation of the antenna is bidirectional with maximum gains of 6.30 and 5.09 dBi for the free space and brick wall versions, respectively.
- 31 May 2017
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Antennas and Propagation
- Vol. 65 (8) , 4274-4277
Wideband CPW-Fed Flexible Bow-Tie Slot Antenna for WLAN/WiMax Systems
A bow-tie antenna based on a slot configuration in a single metal sheet on top of a very thin flexible substrate is introduced. The antenna is constructed from two slotted right-angle triangles fed by a coplanar waveguide transmission line. The topology is very simple and extremely easy to tune in order to reach the proper characteristics after mounting on a supporting structure. A prototype is designed, fabricated, and characterized experimentally. The tunability is proven by considering both the version in free space and the version for use on a brick wall. Measurements demonstrate good agreement with simulations. Both versions cover the wireless local area network (2.4 and 3.65 GHz) and WiMax (2.3, 2.5, and 3.5 GHz) spectra, with an overall impedance bandwidth of 1.79 GHz (57.7%) and 1.46 GHz (49.7%), respectively. The radiation of the antenna is bidirectional with maximum gains of 6.30 and 5.09 dBi for the free space and brick wall versions, respectively.
- Open Access
- 14 November 2012
- Published by Wiley in International Journal of RF and Microwave Computer-Aided Engineering
- Vol. 23 (6) , 639-645
Novel electrically small meander line RFID tag antenna
- 14 November 2012
- Published by Wiley in International Journal of RF and Microwave Computer-Aided Engineering
- Vol. 23 (6) , 639-645
Open AccessNovel electrically small meander line RFID tag antenna