Now showing 1 - 10 of 13
  • Publication
    Reconfigurable pattern patch antenna for mid-band 5G: A review
    ( 2022-01-01)
    Isa S.R.
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    ; ;
    Nebhen J.
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    Kamarudin M.R.
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    Abbasi Q.H.
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    ; ;
    Soh Ping Jack
    New requirements in communication technologies make it imperative to rehash conventional features such as reconfigurable antennas to adapt with the future adaptability advancements. This paper presents a comprehensive review of reconfigurable antennas, specifically in terms of radiation patterns for adaptation in the upcoming Fifth Generation (5G) New Radio frequency bands. They represent the key of antenna technology for materializing a high rate transmission, increased spectral and energy efficiency, reduced interference, and improved the beam steering and beam shaping, thereby land a great promise for planar antennas to boost the mid-band 5G. This review begins with an overview of the underlying principals in reconfiguring radiation patterns, followed by the presentations of the implemented innovative antenna topologies to suit particular advanced features. The various adaptation techniques of radiation pattern reconfigurable planar antennas and the understanding of its antenna design approaches has been investigated for its radiation pattern enhancement. A variety of design configurations have also been critically studied for their compatibilities to be operated in the mid-band communication systems. The review provides new insights on pattern reconfigurable antenna where such antennas are categorized as beam steering antenna and beam shaping antennas where the operation modes and purposes are clearly investigated. The review also revealed that for mid-band 5G communication, the commonly used electronic switching such as PIN diodes have sufficient isolation loss to provide the required beam performance.
  • Publication
    Switchable Beam Antenna with Five Planar Element using PIN Diode in Elevation Plane
    ( 2020-09-28)
    Adan F.H.
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    ; ; ;
    Alaydrus M.
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    Awal M.R.
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    ; ;
    Alomainy A.
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    Kamarudin M.R.
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    Majid H.A.
    This work focuses on the switchable beam parasitic patch antenna for the point to point communication system. This concept gives more flexibility due to their ability to modify the radiation and providing multiple functionalities. This work focuses on two points directly to minimize the number of PIN Diode and to maximize its reconfiguration capabilities. First, the concept of two parasitic element is addressed. The mutual coupling effect between both driven and parasitic has manage to steer the beam to-28{\mathrm{o}}, \ 0{\mathrm{o}} and +28o different angles in a single layer. The design consists of four parasitic elements with full ground and four pin diode switch HPND-4005, five different directions have been reached which are-450,-30{\mathrm{o}}, \ 0{\mathrm{o}}+30{\mathrm{o}} and +450. The parasitic patch antenna has achieved high gain of 8. 92dBi at 5.8 GHz with the beam ability to steer unti145o for both side of the parasitic element.
  • Publication
    A multilayered acoustic signal generator for low power energy harvesting
    This paper presents the design and analysis of a multilayer cantilever to harvest vibration energy by generating acoustic signal. To do so, a five layer configuration is used to design the cantilever. Lead Zirconate Titanate (PZT-8), Stainless Steel 405 Annealed, Aluminum and Zinc Oxide are used to develop the layers. Water is used as the medium to analyze the sound propagation pattern. Sound Pressure Level, displacements and electric potential of the cantilever are analyzed along with other parameters. From the results, it is evident that, the proposed cantilever can propagate sound within a range of 78.7 dB to 73.4 dB in a 50 mm spherical distance.
  • Publication
    Electrically tunable Left-Handed textile metamaterial for microwave applications
    ( 2021)
    Kabir Hossain
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    ; ;
    Ping Jack Soh
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    Mohd Haizal Jamaluddin
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    Samir Salem Al-Bawri
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    R. Badlishah, Ahmad
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    ; ;
    Nitin Saluja
    An electrically tunable, textile-based metamaterial (MTM) is presented in this work. The proposed MTM unit cell consists of a decagonal-shaped split-ring resonator and a slotted ground plane integrated with RF varactor diodes. The characteristics of the proposed MTM were first studied independently using a single unit cell, prior to different array combinations consisting of 1 × 2, 2 × 1, and 2 × 2 unit cells. Experimental validation was conducted for the fabricated 2 × 2 unit cell array format. The proposed tunable MTM array exhibits tunable left-handed characteristics for both simulation and measurement from 2.71 to 5.51 GHz and provides a tunable transmission coefficient of the MTM. Besides the left-handed properties within the frequency of interest (from 1 to 15 GHz), the proposed MTM also exhibits negative permittivity and permeability from 8.54 to 10.82 GHz and from 10.6 to 13.78 GHz, respectively. The proposed tunable MTM could operate in a dynamic mode using a feedback system for different microwave wearable applications.
  • Publication
    Flexible Co-Planar Waveguide (CPW)-Fed Y-Shaped Patch UWB Antenna for Off-Body Communication
    ( 2020-03-18)
    Kassim S.
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    Soh Ping Jack
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    Abdulmalek M.
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    Jamaluddin M.H.
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    Sabli N.S.
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    Yassin M.N.
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    ; ; ;
    Ismail N.
    This paper intends to design an Ultra-Wideband (UWB) antenna for future Internet of Things (IoT) applications for off-body Wireless Body Area Networks (WBAN) communication. An antenna based on the Y-shaped patch fed using co-planar waveguide (CPW) line, with a full ground plane is designed. It is implemented on two different substrates, namely a 5mm thick Rogers RO4350B and a 5-mm-thick felt textile. Parametric analysis of antenna is performed by changing its critical dimensions and monitoring parameters such as gain, bandwidth, efficiency, radiation pattern when using both substrates. Besides that, the bending effects towards reflection coefficient and radiation patterns are also studied. The final patch size with the Y-shaped slot is 36 × 40 mm2 for both substrates. The antenna is capable of providing coverage for the bands from 8 to 10 GHz. Finally, the antenna designed on RO4350B substrate outperforms the antenna designed on felt by about four times in terms of bandwidth, with 3.3 GHz (7.7-11 GHz).
  • Publication
    A negative index nonagonal csrr metamaterial-based compact flexible planar monopole antenna for ultrawideband applications using viscose-wool felt
    ( 2021-08-02)
    Kabir Hossain
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    ; ;
    Abdelghany M.A.
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    Soh Ping Jack
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    ; ; ;
    Al-Bawri S.S.
    In this paper, a compact textile ultrawideband (UWB) planar monopole antenna loaded with a metamaterial unit cell array (MTMUCA) structure with epsilon-negative (ENG) and near-zero refractive index (NZRI) properties is proposed. The proposed MTMUCA was constructed based on a combination of a rectangular-and a nonagonal-shaped unit cell. The size of the antenna was 0.825 λ0 × 0.75 λ0 × 0.075 λ0, whereas each MTMUCA was sized at 0.312λ0 × 0.312λ0, with respect to a free space wavelength of 7.5 GHz. The antenna was fabricated using viscose-wool felt due to its strong metal–polymer adhesion. A naturally available polymer, wool, and a human-made poly-mer, viscose, that was derived from regenerated cellulose fiber were used in the manufacturing of the adopted viscose-wool felt. The MTMUCA exhibits the characteristics of ENG, with a bandwidth (BW) of 11.68 GHz and an NZRI BW of 8.5 GHz. The MTMUCA was incorporated on the planar monopole to behave as a shunt LC resonator, and its working principles were described using an equivalent circuit. The results indicate a 10 dB impedance fractional bandwidth of 142% (from 2.55 to 15 GHz) in simulations, and 138.84% (from 2.63 to 14.57 GHz) in measurements obtained by the textile UWB antenna. A peak realized gain of 4.84 dBi and 4.4 dBi was achieved in simulations and measurements, respectively. A satisfactory agreement between simulations and experiments was achieved, indicating the potential of the proposed negative index metamaterial-based antenna for microwave applications.
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  • Publication
    Elastomeric polydimethylsiloxane polymer on conductive interdigitated electrode for analyzing skin hydration dynamics
    With an approach towards generating a wearable skin hydration detecting system, simple, cheap, and flexible skin hydration sensing strategy was demonstrated here using an interdigitated electrode (IDE) coated with polydimethylsiloxane (PDMS) matrix. Aluminium IDE with a 400 Âµm gap and 250 Âµm electrode sizes were fabricated using a photolithography method. Morphological characterizations were performed using a high power microscope, 3D-profilometer, and scanning electron microscope. The dimensions of electrodes and gaps measured through electron microscopic analysis affirmed the exactness of IDE and the fabrication process. After coated with PDMS polymer, the IDE/PDMS surface was examined under a high power microscope and 3D-profilometer. The optical characterization revealed the polymer was coated on IDE through the color-shade changes and smooth surface observed under an optical microscope and the respective 3D-visualization. IDE/PDMS was also analyzed by an atomic force microscope, revealing the smoothness of the IDE surface. Electrical characterizations were performed using different pH and urea solutions and the sweat to investigate the influence of real-time and artificial sweat on IDE/PDMS. As the device showed appropriate results with real-time sweat and no effect with artificial interferences, it is highly encouraged and recommended for detecting skin hydration and the related illnesses with the point-of-care concept.
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  • Publication
    A Frequency-Reconfigurable Microstrip Antenna with Constant Dipole-Like Radiation Patterns Using Single Bias, Triple Varactor Tuning with Reduced Complexity
    This work proposes a novel frequency-reconfigurable circular patch antenna incorporated with a rectangular slot and a narrow slot capable of producing constant dipole-like radiation patterns. The antenna compactness is achieved with the integration of the rectangular slot defected ground structure (DGS) on the ground. The proposed antenna is able to perform continuous frequency tuning between 1.91 and 2.77 GHz with a frequency ratio of 1.5:1, in addition to stable dipole-like radiation patterns. The resonant frequency of the antenna is controlled by tuning a simple DC biasing network that consists of three RF varactor diodes located on the narrow slot DGS. Implementing the DC biasing network at the narrow slot DGS while maintaining the large slot DGS helps the antenna miniaturization and maintains the constant dipole-like radiation pattern over all frequency tuning range. The results are validated via simulations and experimental validations in terms of reflection coefficients and the radiation patterns. Measurements indicated that an impedance bandwidth of 85 MHz is featured for each tuned frequency band, with dipole-like patterns and an average gain of 1.57 dBi.
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  • Publication
    Investigation on the Mutual Coupling Reduction in MIMO Antenna using Dual Split CSRR EBG
    ( 2021-07-26)
    Alsayaghi A.
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    Kabir Hossain
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    Jayaprakasam S.
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    Raghava N.S.
    In many applications, it is now desirable to prevent a device from being affected by an external electromagnetic field or prevent the device's intrusion into the electromagnetic field. The elimination or reduction of coupling between neighbouring systems is desired, and this is achieved through the use of electromagnetic shields and absorbers. This project focuses on an investigation that analysed the band-gap region for unit cell EBG simulation and unit cell array simulation. It is revealed that unit cell simulation provides an accurate result where the band-gap region is from 2 GHz to 3.5 GHz. The performance of the EBG is validated using a microstrip MIMO antenna. Using EBG, the S21 is reduced from -18.63 dB to -28.80 dB. Meanwhile, the MIMO antenna gain with the proposed EBG is 2.78 dBi, greater than MIMO antenna without EBG (2.47 dBi).
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  • Publication
    Design of Electronically Steerable High Mode Dielectric Resonator Antenna using PIN Diode
    This paper presents a reconfigurable beam dielectric resonator antenna (DRA) at 2.4 GHz by adopting the yagi-uda concept. Rectangular dielectric resonator antenna (RDRA) have been chosen as the radiator and fed by slot aperture. The antenna is designed in Taconic substrate with permittivity of 2.2. Firstly, a single antenna with two different modes is designed and investigated. The best performance mode in term of gain is then used to design the single driven RDRA with two parasitic RDRA, connected with the four RF pin diode BAR50-02V as switch. The analysis of the gap between driven and parasitic element is investigated. Four different types of switch configuration have been carried out to identify the performance of antenna in different cases. Depending on the switch configurations, the designed antenna can achieved highest gain of 7.386 dB and have steering angle capability at-42°, 42°,-54° and 54°.
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