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Öğe A Deep Analysis of CPW-fed Planar Antennas for Frequencies 2.6 Up to 13.6 GHz(Wydawnictwo Sigma-Not Sp Zoo, 2023) Al-Gburi, Ahmed Jamal Abdullah; Zakaria, Zahriladha; Ibrahim, Imran Mohd; Khabba, Asma; Al-Obaidi, Aymen Dheyaa Khaleel; Saeidi, Tale; Paul, Liton ChandraThis paper presents a deep analysis of coplanar waveguide (CPW) feed Planar antenna for frequencies from 2.6 GHz up to 13.6 GHz, which covers the authorised Ultra-wideband (UWB) from 3.1-10.6GHz and the X-band from 8-12GHz applications. The Parametric analysis will help the researchers understand antenna parameters' effects on the reflection coefficient (S11) variations. These important parameters are the length of the CPW fed (Cl), the width of the substrate (W), the width of the feed-line (Wf) and the gap between the feed-line and CPW disk (g). The total physical planar antenna dimension is 26 mm x 26mm x 1.6 mm, corresponding to the centre frequency range at 7.5 GHz. The UWB CPW planar antenna is fed via a coplanar waveguide (CPW) to attain the best impedance matching for UWB systems. The presented CPW planar antenna has an impedance UWB bandwidth of 11.0 GHz from 2.6 GHz up to 13.6 GHz at -10 dB return loss. The simulated UWB planar antenna displays an omnidirectional radiation behaviour with a simulated gain of 7.3 dB at 13.6 GHz, a directivity of 7.5 dBi at 13.6 GHz and favourable radiation efficiency of 97%. The presented antenna has the specialised prospect to be used for UWB and X-band systems.Öğe Enhancing connectivity/mobility in WBAN applications through detachable wearable multi-band MIMO antenna(Institute of Physics, 2024) Saeidi, Tale; Saleh, Sahar; Timmons, Nick; Karamzadeh, Saeid; Al-Gburi, Ahmed Jamal Abdullah; Razzaz, FaroqThe connectivity and mobility of a miniaturized multi-band four-port textile leaky wave multiple-input multiple-output (MIMO) antenna designed on a layer of denim (ϵr = 1.6, tanδ = 0.006) is enhanced by integrating it with two detachable spiral buttons designed on circular PTFE substrate (ϵr = 2.1, tanδ = 0.001). The connectivity and mobility enhancement of the proposed antenna is evaluated in terms of radiation and diversity parameters. Nested hexagonal split rings behind the buttons, U-shaped slots on textiles, a comb-shaped neutralization network, and an aperture-coupled feed technique are utilized. The unique structure of the buttons on a rigid substrate and the leaky wave antenna on the textile and their integration, the periodic nested elliptical and circular split ring resonators (CSRRs) slots on the aperture coupled to ground, are to expand the connectivity and mobility of the proposed MIMO antenna by offering multiple bands, higher isolation, broadside radiation, and low specific absorption rate (SAR). The leaky wave and button antennas have dimensions of 40 × 30 × 1 mm3 and a diameter of only 13 mm, respectively. The operational bands are 0.86-2.75 GHz, 2.9-4.85 GHz, 5.75-6.15 GHz, and 8-9.85 GHz, covering the L, C, S, and X bands. Additionally, diversity performance is evaluated by defining the envelope correlation coefficient (ECC), diversity gain (DG), Channel Capacity Loss (CCL), and mean effective gain (MEG). The simulation and measurement findings are in good agreement. Following that, it offers a maximum gain of 8.25 dBi, low SAR (<0.05), an ECC below 0.05, DG above 9.85 dB, CCL< 0.25 bits/s/Hz, MEG <−3 dB, Circular polarization (CP), and strong isolation (>22 dB) between every two ports. These features make the proposed antenna an ideal option for MIMO communications and suitable for wireless local area network (WLAN) and fifth-generation (5G) communications. © 2024 IOP Publishing Ltd.Öğe Enhancing connectivity/mobility in WBAN applications through detachable wearable multi-band MIMO antenna(IOP publishing, 2024) Saeidi, Tale; Saleh, Sahar; Timmons, Nick; Karamzadeh, Saeid; Al-Gburi, Ahmed Jamal Abdullah; Razzaz, FaroqThe connectivity and mobility of a miniaturized multi-band four-port textile leaky wave multiple-input multiple-output (MIMO) antenna designed on a layer of denim (epsilon(r) = 1.6, tan delta = 0.006) is enhanced by integrating it with two detachable spiral buttons designed on circular PTFE substrate (epsilon(r) = 2.1, tan delta = 0.001). The connectivity and mobility enhancement of the proposed antenna is evaluated in terms of radiation and diversity parameters. Nested hexagonal split rings behind the buttons, U-shaped slots on textiles, a comb-shaped neutralization network, and an aperture-coupled feed technique are utilized. The unique structure of the buttons on a rigid substrate and the leaky wave antenna on the textile and their integration, the periodic nested elliptical and circular split ring resonators (CSRRs) slots on the aperture coupled to ground, are to expand the connectivity and mobility of the proposed MIMO antenna by offering multiple bands, higher isolation, broadside radiation, and low specific absorption rate (SAR). The leaky wave and button antennas have dimensions of 40 x 30 x 1 mm(3) and a diameter of only 13 mm, respectively. The operational bands are 0.86-2.75 GHz, 2.9-4.85 GHz, 5.75-6.15 GHz, and 8-9.85 GHz, covering the L, C, S, and X bands. Additionally, diversity performance is evaluated by defining the envelope correlation coefficient (ECC), diversity gain (DG), Channel Capacity Loss (CCL), and mean effective gain (MEG). The simulation and measurement findings are in good agreement. Following that, it offers a maximum gain of 8.25 dBi, low SAR (<0.05), an ECC below 0.05, DG above 9.85 dB, CCL< 0.25 bits/s/Hz, MEG <-3 dB, Circular polarization (CP), and strong isolation (>22 dB) between every two ports. These features make the proposed antenna an ideal option for MIMO communications and suitable for wireless local area network (WLAN) and fifth-generation (5G) communications.Öğe Health Control of Tree Trunk Utilizing Microwave Imaging and Reverse Problem Algorithms(Amer Chemical Soc, 2023) Alhawari, Adam R. H.; Saeidi, Tale; Ismail, Idris; Alsuwian, Turki; Al-Gburi, Ahmed Jamal AbdullahThe voids in their trunk significantly affect tropical trees' health. Both the wood and timber industries may face substantial financial losses because of the lack of an effective technique to inspect the defected trees through deep zonal monitoring. Microwave imaging offers the advantages of mobility, processing time, compactness, and resolution over alternative imaging methods. An ultra-wide band (UWB) imaging system consisting of UWB antennas and a reverse problem algorithm is proposed. Several conditions, such as the size of trunk samples (16-30 cm), number of targets, size of voids, heterogeneity of media, and number of layers, are considered in experimental studies. Based on these studies, cylindrical wooden models with 100 and 140 mm diameters, one void at the center, and three voids in different locations were 3D printed. After proving the system's ability through simulation and measurements on 3D models, a rubber-wood trunk with a length of 75 cm was cut into smaller pieces. The images created utilizing the measured data showed that the system could detect voids in the rubber trunk. Furthermore, the system indicated a high percentage of reliability and repeatability.Öğe High gain multi-band circularly polarized wearable leaky wave zipper MIMO antenna(Cell press, 2024) Saeidi, Tale; Saleh, Sahar; Mahmood, Sarmad Nozad; Timmons, Nick; Al-Gburi, Ahmed Jamal Abdullah; Karamzadeh, Saeid; Razzaz, FaroqA miniaturized, multi-band, four-port wearable Multiple Input Multiple Output (MIMO) antenna is proposed, which contains a leaky wave textile antenna (LWTA) on denim (epsilon(r) = 1.6, tan delta = 0.006) as substrate and Shieldit Super Fabric as conductor textile. The concept in this work involves incorporating the metal and plastic zipper into the garment to function as an antenna worn on the body. Simulations and measurements have been conducted to explore this idea. The LWTA has dimensions of 40 x 30 x 1 mm(3). Every two ports are separated by a zipper with two different kinds of materials: Acetal Polymer Plastic (APP) and 90 % brass to improve the isolation, gain, and Impedance bandwidth. The antenna operates in the frequency ranges covering the L, C, S, and X bands. Additionally, diversity performance is evaluated using the Envelope Correlation Coefficient (ECC) and diversity gain (DG). Simulation and measurement findings agree well, with a maximum gain of 12.15 dBi, low Specific Absorption Rate (SAR) based on the standards, DG greater than 9.65 dB, circular polarization (CP), and strong isolation (<-23 dB) between each port. Since the antenna's characteristics do not change significantly under bending and when the zipper is opened, the proposed antenna is a viable candidate for body-centric wireless communications on the battlefield. For example, it can facilitate communication covering wireless local area network (WLAN) and fifth-generation (5G) communications.Öğe Meta Surface-Based Multiband MIMO Antenna for UAV Communications at mm-Wave and Sub-THz Bands(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Saeidi, Tale; Saleh, Sahar; Timmons, Nick; Al-Gburi, Ahmed Jamal Abdullah; Karamzadeh, Saeid; Althuwayb, Ayman A.; Rashid, Nasr; Kaaniche, Khaled; Ben Atitallah, Ahmed; Elhamrawy, Osama I.Unmanned aerial vehicles (UAVs) need high data rate connectivity, which is achievable through mm-waves and sub-THz bands. The proposed two-port leaky wave MIMO antenna, employing a coplanar proximity technique that combines capacitive and inductive loading, addresses this need. Featuring mesh-like slots and a vertical slot to mitigate open-stopband (OSB) issues, the antenna radiates broadside and bidirectionally. H-shaped slots on a strip enhance port isolation, and a coffee bean metasurface (MTS) boosts radiation efficiency and gain. Simulations and experiments considering various realistic scenarios, each at varying vertical and horizontal distances, show steered beam patterns, circular polarization (CP), and high-gain properties, with a maximum gain of 13.8 dBi, an axial ratio (AR) <2.9, a diversity gain (DG) >9.98 dB, and an envelope correlation coefficient (ECC) <0.003. This design supports drones-to-ground (D2G), drone-to-drone (D2D), and drone-to-satellite (D2S) communications. © 2024 by the authors.Öğe A Miniaturized and Highly Sensitive Microwave Sensor Based on CSRR for Characterization of Liquid Materials(Mdpi, 2023) Al-Gburi, Ahmed Jamal Abdullah; Zakaria, Zahriladha; Abd Rahman, Norhanani; Althuwayb, Ayman A.; Ibrahim, Imran Mohd; Saeidi, Tale; Dayo, Zaheer AhmedIn this work, a miniaturized and highly sensitive microwave sensor based on a complementary split-ring resonator (CSRR) is proposed for the detection of liquid materials. The modeled sensor was designed based on the CSRR structure with triple rings (TRs) and a curve feed for improved measurement sensitivity. The designed sensor oscillates at a single frequency of 2.5 GHz, which is simulated using an Ansys HFSS simulator. The electromagnetic simulation explains the basis of the mode resonance of all two-port resonators. Five variations of the liquid media under tests (MUTs) are simulated and measured. These liquid MUTs are as follows: without a sample (without a tube), air (empty tube), ethanol, methanol, and distilled water (DI). A detailed sensitivity calculation is performed for the resonance band at 2.5 GHz. The MUTs mechanism is performed with a polypropylene tube (PP). The samples of dielectric material are filled into PP tube channels and loaded into the CSRR center hole; the E-fields around the sensor affect the relationship with the liquid MUTs, resulting in a high Q-factor value. The final sensor has a Q-factor value and sensitivity of 520 and 7.032 (MHz)/e(r)) at 2.5 GHz, respectively. Due to the high sensitivity of the presented sensor for characterizing various liquid penetrations, the sensor is also of interest for accurate estimations of solute concentrations in liquid media. Finally, the relationship between the permittivity and Q-factor value at the resonant frequency is derived and investigated. These given results make the presented resonator ideal for the characterization of liquid materials.Öğe A Miniaturized Full-Ground Dual-Band MIMO Spiral Button Wearable Antenna for 5G and Sub-6 GHz Communications(Mdpi, 2023) Saeidi, Tale; Al-Gburi, Ahmed Jamal Abdullah; Karamzadeh, SaeidA detachable miniaturized three-element spirals radiator button antenna integrated with a compact leaky-wave wearable antenna forming a dual-band three-port antenna is proposed. The leaky-wave antenna is fabricated on a denim (epsilon(r) = 1.6, tan delta = 0.006) textile substrate with dimensions of 0.37 lambda(0) x 0.25 lambda(0) x 0.01 lambda(0) mm(3) and a detachable rigid button of 20 mm diameter (on a PTFE substrate epsilon(r) = 2.01, tan delta = 0.001). It augments users' comfort, making it one of the smallest to date in the literature. The designed antenna, with 3.25 to 3.65 GHz and 5.4 to 5.85 GHz operational bands, covers the wireless local area network (WLAN) frequency (5.1-5.5 GHz), the fifth-generation (5G) communication band. Low mutual coupling between the ports and the button antenna elements ensures high diversity performance. The performance of the specific absorption rate (SAR) and the envelope correlation coefficient (ECC) are also examined. The simulation and measurement findings agree well. Low SAR, <-0.05 of LCC, more than 9.5 dBi diversity gain, dual polarization, and strong isolation between every two ports all point to the proposed antenna being an ideal option for use as a MIMO antenna for communications.Öğe Ultra-wideband (UWB) antennas for breast cancer detection with microwave imaging: A review(Elsevier B.V., 2025) Saeidi, Tale; Mahmood, Sarmad Nozad; Saleh, Sahar; Timmons, Nick; Al-Gburi, Ahmed Jamal Abdullah; Razzaz, FaroqIn recent years, microwave imaging has attracted much attention and offers several advantages over existing imaging systems. It allows for a thorough examination of biological tissues, making it possible to identify changes in their shape and pinpoint their exact locations. One exciting development in this field is ultra-wideband (UWB) microwave imaging, which delivers superior results while using radiation that is not harmful. Antennas are a crucial part of UWB systems and require careful optimization, especially considering their proximity to the human body. Various factors need to be considered when designing antennas, including the choice of materials and dimensions, operational bandwidth, the impact of the human body on antenna performance, and the dynamics of short-pulse propagation. Recent research has focused on improving electromagnetic sensors used in these systems, whether as standalone units or as part of antenna arrays. This paper aims to comprehensively review significant advancements in high-performance UWB antenna sensors used in microwave imaging systems utilized for breast cancer detection. © 2025 The Authors
