Mohd Najib Mohd Yasin
Thumbnail Image
Preferred name
Mohd Najib Mohd Yasin
Official Name
Mohd Najib , Mohd Yasin
Alternative Name
M. Yasin, M. Najib
Yasin, Mohd Najib
Yasin, Mohd Najib M.
Yasin, M. N.Mohd
Mohd Yasin, M. N.
Main Affiliation
Scopus Author ID
57210314287
Researcher ID
AAQ-6242-2021

Research Output

Filters

25
Reset filters

Settings
Now showing 1 - 10 of 25
  • Publication
    Reconfigurable pattern patch antenna for mid-band 5G: A review
    ( 2022-01-01)
    Isa S.R.
    ;
    Muzammil Jusoh
    ;
    Thennarasan Sabapathy
    ;
    Nebhen J.
    ;
    Kamarudin M.R.
    ;
    Mohamed Nasrun Osman
    ;
    Abbasi Q.H.
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Mohd Najib Mohd Yasin
    ;
    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.
    ;
    Muzammil Jusoh
    ;
    Thennarasan Sabapathy
    ;
    Mohamed Nasrun Osman
    ;
    Alaydrus M.
    ;
    Awal M.R.
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Mohd Najib Mohd Yasin
    ;
    Alomainy A.
    ;
    Kamarudin M.R.
    ;
    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
    Higher Order OAM Mode Generation Using Wearable Antenna for 5G NR Bands
    ( 2023-01-01)
    Noor S.K.
    ;
    Arif Mawardi Ismail
    ;
    Mohd Najib Mohd Yasin
    ;
    Mohamed Nasrun Osman
    ;
    Thennarasan Sabapathy
    ;
    Shakhirul Mat Salleh
    ;
    Soh Ping Jack
    ;
    Rambe A.H.
    ;
    Ramli N.
    This paper presents a flexible and wearable textile array antenna designed to generate Orbital Angular Momentum (OAM) waves with Mode +2 at 3.5 GHz (3.4 to 3.6 GHz) of the sub-6 GHz fifth-generation (5G) New Radio (NR) band. The proposed antenna is based on a uniform circular array of eight microstrip patch antennas on a felt textile substrate. In contrast to previous works involving the use of rigid substrates to generate OAM waves, this work explored the use of flexible substrates to generate OAM waves for the first time. Other than that, the proposed antenna was simulated, analyzed, fabricated, and tested to confirm the generation of OAM Mode +2. With the same design, OAM Mode −2 can be generated readily simply by mirror imaging the feed network. Note that the proposed antenna operated at the desired frequency of 3.5 GHz with an overall bandwidth of 400 MHz in free space. Moreover, mode purity analysis is carried out to verify the generation of OAM Mode +2, and the purity obtained was 41.78% at free space flat condition. Furthermore, the effect of antenna bending on the purity of the generated OAM mode is also investigated. Lastly, the influence of textile properties on OAM modes is examined to assist future researchers in choosing suitable fabrics to design flexible OAM-based antennas. After a comprehensive analysis considering different factors related to wearable applications, this paper demonstrates the feasibility of generating OAM waves using textile antennas. Furthermore, as per the obtained Specific Absorption Rate (SAR), it is found that the proposed antenna is safe to be deployed. The findings of this work have a significant implication for body-centric communications.
  • Publication
    Analysis of Symmetric Two and Four-coil Magnetic Resonant Coupling Wireless Power Transfer
    ( 2022-04-01)
    Ali A.
    ;
    Mohd Najib Mohd Yasin
    ;
    Rambe A.H.
    ;
    Ismahayati Adam
    ;
    Ramli N.
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Thennarasan Sabapathy
    ;
    Mohd Natashah Norizan
    ;
    Sobri S.A.
    This study examined the efficiency of power transfer for two-coil and four-coil spiral magnetic resonant coupling wireless power transfer (WPT) using distance to coil diameter (D/dm) ratio and reflection coefficient, S21 value. Adding resonators reduced the total resistance in the two-coil WPT system while increasing the S21 values of the whole system. A same-size spiral coil was proposed for the system and simulated using computer simulation technology (CST). A prototype with similar specifications for a four-coil design was implemented for verification. The proposed method yielded an optimal efficiency of 76.3% in the four-coil system, while the two-coil WPT yielded a 23.2% efficiency with a 1.33 D/dm ratio.
  • Publication
    Multi-stage feature selection (MSFS) algorithm for UWB-based early breast cancer size prediction
    ( 2020-08-01)
    Vijayasarveswari V.
    ;
    Allan Melvin Andrew
    ;
    Muzammil Jusoh
    ;
    Thennarasan Sabapathy
    ;
    Rafikha Aliana A Raof
    ;
    Mohd Najib Mohd Yasin
    ;
    R Badlishah Ahmad
    ;
    Khatun S.
    ;
    Hasliza A Rahim @ Samsuddin
    Breast cancer is the most common cancer among women and it is one of the main causes of death for women worldwide. To attain an optimum medical treatment for breast cancer, an early breast cancer detection is crucial. This paper proposes a multistage feature selection method that extracts statistically significant features for breast cancer size detection using proposed data normalization techniques. Ultra-wideband (UWB) signals, controlled using microcontroller are transmitted via an antenna from one end of the breast phantom and are received on the other end. These ultra-wideband analogue signals are represented in both time and frequency domain. The preprocessed digital data is passed to the proposed multistage feature selection algorithm. This algorithm has four selection stages. It comprises of data normalization methods, feature extraction, data dimensional reduction and feature fusion. The output data is fused together to form the proposed datasets, namely, 8-HybridFeature, 9-HybridFeature and 10-HybridFeature datasets. The classification performance of these datasets is tested using the Support Vector Machine, Probabilistic Neural Network and Naïve Bayes classifiers for breast cancer size classification. The research findings indicate that the 8-HybridFeature dataset performs better in comparison to the other two datasets. For the 8-HybridFeature dataset, the Naïve Bayes classifier (91.98%) outperformed the Support Vector Machine (90.44%) and Probabilistic Neural Network (80.05%) classifiers in terms of classification accuracy. The finalized method is tested and visualized in the MATLAB based 2D and 3D environment.
  • Publication
    Bending Assessment of Dual-band Split Ring-shaped and Bar Slotted All-Textile Antenna for Off-body WBAN/WLAN and 5G Applications
    ( 2020-09-28)
    Mashaghba H.A.
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Soh Ping Jack
    ;
    Abdulmalek M.
    ;
    Ismahayati Adam
    ;
    Muzammil Jusoh
    ;
    Thennarasan Sabapathy
    ;
    Mohd Najib Mohd Yasin
    ;
    Khairul Najmy Abdul Rani
    This paper presents a dual-band split ring-shaped and bar slotted textile antenna for potential WBAN/WLAN and 5G applications. The antenna is made using textiles and features a full ground plane to possibly alleviate coupling to the human body. The overall size of the antenna is 70 x 70 mm2, with a patch sized at 47.2 x 31 mm2 0.472 \lambda \times 0.031 \lambda. The antenna is made using ShieldIt Super as its conductive textile and felt as its substrate. To enable its dual-band resonance at 2.45 and 3.5 GHz a split ring-shaped and bar slots are integrated onto the patch. The proposed antenna is evaluated when bent under different radii and at different axes to estimate its performance in terms of reflection coefficient, bandwidth, efficiency and gain. A 10-dB impedance bandwidth of 57 % or 135 MHz (from 2.39 to 2.52 GHz) and 70 % or 240 MHz (from 3.45 to 3.56 GHz) are obtained when evaluated in the planar /bent configuration. The maximum realized gain is 6 dBi for at 3.5 GHz. These performances indicate that the antenna proposed in this work can be potentially improved for applications in WBAN/WLAN and 5G bands.
  • Publication
    Low-Profile and Wider-Angle Beam Tilting Parasitic Array Resonator Antenna with Optimized Deflected Ground Plane on FR-4 Substrate
    ( 2023-04-01)
    Mohd Zainudin N.A.F.
    ;
    Mohamed Nasrun Osman
    ;
    Thennarasan Sabapathy
    ;
    Muzammil Jusoh
    ;
    Mohd Najib Mohd Yasin
    ;
    Mohamad M.K.
    A low-profile and wide-angle radiation pattern reconfigurable antenna is designed, analyzed, and fabricated for wireless sensor network (WSN) applications, which operate at a 2.5-GHz frequency. This work aims to minimize the number of switches and optimize the parasitic size and ground plane to achieve a steering angle of more than 30° using a low cost-high loss FR-4 substrate. The radiation pattern reconfigurability is achieved by introducing four parasitic elements surrounding a driven element. In this work, the single driven element is fed by a coaxial feed, while other parasitic elements are integrated with the RF switches on the FR-4 as the substrate with dimensions of 150 × 100 mm (1.67 × 2.5 λo). The RF switches of the parasitic elements are surface mounted on the substrate. By truncating and modifying the ground plane, the beam steering can be achieved at more than 30° on the xz plane. Additionally, the proposed antenna can attain an average tilt angle of more than 10° on the yz plane. The antenna is also capable of attaining other important results, such as a fractional bandwidth of 4% at 2.5 GHz and an average gain of 2.3 dBi for all configurations. By adopting the ON/OFF condition on the embedded RF switches, the beam steering can be controlled at a certain angle, thus increasing the tilting angle of the wireless sensor networks. With such a good performance, the proposed antenna has high potential to serve as a base station in WSN applications.
  • Publication
    Design of Reconfigurable Antenna for RFID System
    ( 2021-07-26)
    Renukka Sivakumar
    ;
    Thennarasan Sabapathy
    ;
    Muzammil Jusoh
    ;
    Soh Ping Jack
    ;
    Mohamed Nasrun Osman
    ;
    Salem Al-Bawri S.
    ;
    Jayaprakasam S.
    ;
    Mohd Najib Mohd Yasin
    ;
    Saluja N.
    This paper proposes a reconfigurable antenna for RFID system which can operate between 860MHz to 960MHz frequency that belongs to ultra-high frequency (UHF) band used in Malaysia with the center frequency of 910MHz. One rectangular slot and two triangle-shaped slots are used in designing this antenna. A good circular polarization obtained from the slotted structure along the diagonal axis in the design. RF pin diodes are used as the switching mechanism of the antenna. However, in this work to proof the concept of switching mechanism, copper pins are used as artificial switches. Parasitic elements are deployed on the right and left side of the driven element to assist the radiation pattern reconfiguration. Overall, the proposed antenna able to steer the beam at approximately at -30 , -16 , and 10 with peak gain of 3.2dB and average gain of 2.5dB. With this result, overall coverage of UHF RFID reader antenna could be improved.
  • Publication
    Electrically tunable Left-Handed textile metamaterial for microwave applications
    ( 2021)
    Kabir Hossain
    ;
    Thennarasan Sabapathy
    ;
    Muzammil Jusoh
    ;
    Ping Jack Soh
    ;
    Mohd Haizal Jamaluddin
    ;
    Samir Salem Al-Bawri
    ;
    Mohamed Nasrun Osman
    ;
    R. Badlishah, Ahmad
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Mohd Najib Mohd Yasin
    ;
    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
    A novel unsupervised spectral clustering for pure-tone audiograms towards hearing aid filter bank design and initial configurations
    ( 2022-01-01)
    Elkhouly A.
    ;
    Allan Melvin Andrew
    ;
    Hasliza A Rahim @ Samsuddin
    ;
    Abdulaziz N.
    ;
    Abdulmalek M.
    ;
    Mohd Najib Mohd Yasin
    ;
    Muzammil Jusoh
    ;
    Thennarasan Sabapathy
    ;
    Siddique S.
    The current practice of adjusting hearing aids (HA) is tiring and time-consuming for both patients and audiologists. Of hearing-impaired people, 40–50% are not satisfied with their HAs. In addition, good designs of HAs are often avoided since the process of fitting them is exhausting. To improve the fitting process, a machine learning (ML) unsupervised approach is proposed to cluster the pure-tone audiograms (PTA). This work applies the spectral clustering (SP) approach to group audiograms according to their similarity in shape. Different SP approaches are tested for best results and these approaches were evaluated by Silhouette, Calinski-Harabasz, and Davies-Bouldin criteria values. Kutools for Excel add-in is used to generate audiograms’ population, annotated using the results from SP, and different criteria values are used to evaluate population clusters. Finally, these clusters are mapped to a standard set of audiograms used in HA characterization. The results indicated that grouping the data in 8 groups or 10 results in ones with high evaluation criteria. The evaluation for population audiograms clusters shows good performance, as it resulted in a Silhouette coefficient >0.5. This work introduces a new concept to classify audiograms using an ML algorithm according to the audiograms’ similarity in shape.