Syed Alwee Aljunid Syed Junid
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Syed Alwee Aljunid Syed Junid
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Syed Alwee Aljunid, Syed Junid
Alternative Name
Aljunid, S.
Aljunid, Syed Alwi
Aljunid, Syed A.
Aljunid, S. Alwee
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Scopus Author ID
56000543300

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  • Publication
    Compact multilayer wideband symmetric five-port reflectometer
    ( 2017-04-01)
    Samir Salem Al-Bawri
    ;
    Mohd Faizal Jamlos
    ;
    Siti Zuraidah Ibrahim
    ;
    Syed Alwee Aljunid Syed Junid
    This article presents a new design of a wideband, compact, and low-cost symmetric five-port reflectometer (5PR). The proposed 5PR features a wide operational bandwidth of 3240 MHz (about 162% centered at 2 GHz). Five-symmetric branch-lines consist of SCURVE, STEE, SLIN, and Term were designed and optimized to achieve an equivalent value of 78 dB for S11, S22, S33, S44, and S55 at center frequency of 2 GHz. Such consistent value between those S-parameters proven a perfect matching impedance are successfully obtained by proposed symmetric 5PR even own a bandwidth as high as 162%. Moreover, the simulated and measured results show the proposed 5PR has realized magnitude of ≈ 0 dB (S11), 0.5 (S12, S13, S14, S15, S21, S23 … S54) as well as phase relative error of 120° which in parallel to theoretical values. With all capabilities mentioned, the proposed 5PR is a promising candidate to be installed in a microwave imaging system for biomedical applications in the future. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:802–805, 2017.
  • Publication
    Medical healthcare M2M system using the VLC system
    ( 2020-01-08)
    Norhidayah Abd Aziz
    ;
    Anuar Mat Safar
    ;
    Mohd Rashidi Che Beson
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Rosdisham Endut
    The RF communication has suffered from the interference and excessive latency issues. It is required a separated setup for transmission and reception of RF waves. To overcome this problem, the VLC system is a chosen technique due to high bandwidth and immunity to interference from electromagnetic sources. In this project, Optisystem Software version 15 has been chosen to study the perfomances of the VLC system in directed LOS. The performance results will be displayed on BER analyser and the simulation that has been done is iterating continuously in order to get the acceptable results. The result indicates that the reading of simulation of 1 user for both bit rate 155Mbps and 622Mbps shows the best result compared to 4 users. Without using any kind of OCDMA system, the number of users will reach the limitations which is not more than 4 users. The number of users influences the performance of the system and the result shows the decrement of BER reading which is lower than 10-9.
  • Publication
    Prediction model for spectroscopy using python programming
    ( 2021-12)
    A A M Ismail
    ;
    Norshamsuri Ali @ Hasim
    ;
    Mohd Shafiq Amirul
    ;
    Rosdisham Endut
    ;
    Syed Alwee Aljunid Syed Junid
    This paper is motivated by searching for the perfect pattern for the spectroscopy spectra using artificial neural networks (ANN) using python programming coding. The pattern from the spectroscopy is based on the absorption and emission of light and other radiation by materials in relation to the wavelength dependence of these processes. Spectral equipment such as spectrometers, spectral analysers, spectrographs, or spectrophotometers is utilised to determine spectrum values. The problem in this spectroscopy is to identify the sample or analyte, which can be solved by a prediction model for spectroscopy using Python. These problems occur when finding the best algorithm of pre-processing techniques that can predict any model accurately into an understandable format for prediction models. Various types of pre-processing techniques have been used, such as Multiplicative Scatter Correction (MSC), Inverse MSC, Extended MSC (EMSC), Extended Inverse MSC, de-trending, Standard Normal Variate (SNV) and normalisation in order to get a better r2 value. In this project, we find the r2 and the root mean square error (RMSE) to evaluate the prediction values and the actual values. First, choosing pre-processing techniques and then finding the best statistical method for constructing predictive models that produce high accuracy. We used ANN in this project as a prediction model. Based on the results, we managed to achieve our objective, which is that the prediction model has more than 90% of accuracy. Furthermore, the results show that our prediction model has 1.0 accuracy at 100 Epoch with a 0.3 learning rate. Finally, we can conclude that our prediction model can be used to predict the spectroscopy-based data format.
  • Publication
    Enrichment of wireless data transmission based on visible light communication for triple play service application
    ( 2020-01-08)
    Mat N.R.N.
    ;
    Mohd Rashidi Che Beson
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Rosdisham Endut
    ;
    Norshamsuri Ali @ Hasim
    In this paper, the performance of the LiFi-IoT based on VLC for point-to-point (P2P) topology has been investigated. LiFi-IoT offers a possibility to deploy high speed (∼1 Gbps) wireless data for future network access optical wireless communication (UOWC). Result shows that, the LED threshold current of 16 mA corresponds to a voltage of 0.6 V. At the injection current of 30 mA, the LED has an output optical power of 18 mW for data transmission to be carried out under the optical communication environment based on Line of Sight (LoS).
  • Publication
    Hybrid WDM and Optical-CDMA over Multi-Mode Fiber Transmission System based on Optical Vortex
    ( 2021-03-01)
    Ghazi A.
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Syed Zulkarnain Syed Idrus
    ;
    Rosdisham Endut
    ;
    Mohd Rashidi Che Beson
    ;
    Ali N.
    ;
    A.dawoodi
    ;
    Fakhrudeen A.M.
    ;
    Fareed A.
    ;
    Sharma T.
    The optical vortex has recently attracted scholars to implement it in optical tweezers, microscopy, optical communications, quantum information processing, optical trapping, and laser machining. Optical vortex beam applied classically that can be transferred to the transverse amplitude of a heralded single-photon, and optical vortex possesses a helical wavefront and carries orbital angular momentum. In this study, Optical vortex is applied in optical-CDMA (optical code-division multiple-access) in conjunction with WDM (wavelength division multiplexing). This mechanism aims to increase the capacity and security in optical communication significantly. The implementation of Laguerre-Gaussian (LG) modes with optical vortex based on one dimension zero cross-correlation (ZCC) code shows that mode coupling reduces effectively. Consequently, a positive increase in channel performance and response. Accordingly, the LG modes based on the 1D-ZCC code are investigated and propagated over multi-mode fiber (MMF) based on an optical vortex, which also substantially reduces channel effects. Consequently, all these attributes combined will result in a hybrid WDM-Optical-CDMA with an optical vortex system over MMF.
  • Publication
    Comparison of MD & ZCC one dimension code for optical-cdma over multi-mode fiber based on laguerre-gaussian modes
    ( 2021-08-01)
    Ghazi A.
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Syed Zulkarnain Syed Idrus
    ;
    Fareed A.
    ;
    Hamood L.
    ;
    Rosdisham Endut
    ;
    Ali N.
    ;
    Mohd Rashidi Che Beson
    ;
    Fakhrudeen A.M.
    ;
    Al-Dawoodi A.
    ;
    Matem R.
    ;
    Abdullah S.S.
    This paper compares multi diagonal (MD) and zero cross-correlation (ZCC) onedimension codes for optical code division multiple access (Optical-CDMA). In our system, Laguerre-Gaussian modes over a multi-mode fiber (MMF) transmission system based on two different codes have been proposed. Computer simulation software (Opti-system) is used to design the system in a short-haul local-area network (LAN) to evaluate high-capacity optical data links. In the design, the data is transmitted via Spatial vertical-cavity surface-emitting laser (on Spatial VCSEL) with a 1550 nm wavelength. The adopted Laguerre- Gaussian modes are (LG 0 3, LG 02 and LG 01). Over different distances, we evaluate our system by conducting several simulation experiments to measure the parameters: Bit error rates, Q-Factor and eye diagrams.
  • Publication
    Prediction of soil macronutrient (nitrate and phosphorus) using near-infrared (NIR) spectroscopy and machine learning
    ( 2020-01-08)
    Laili A.R.
    ;
    Rosdisham Endut
    ;
    Norshamsuri Ali @ Hasim
    ;
    Laili M.H.
    ;
    Amirul M.S.
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Mohd Rashidi Che Beson
    ;
    Ismail M.N.M.
    Determination of basic soil macronutrients such as nitrogen (N), phosphorus (P) and potassium (K) that dissolve from organic matter (OM) prior to the plantation of fruit and vegetable corps is one of the important process of soil preparation towards precision farming. In this paper comparative analysis is performed for detection algorithm on OM, (N) and (P) sample using near infrared spectroscopy (NIRS) spectrometer in reflective mode with an effective range of 900nm to 1700nm. In pre-processing we execute data dimension reduction by combining multiple feature selection such as data normalization, permutation feature importance, principle component analysis, fisher linear discriminant and filter-based feature selection. Pre-processing able to reduce 50% data dimension. For prediction model development we combine with multiple classification algorithm such as multiclass decision jungle, decision forest, logistic regression and neural network to come out with highest accuracy of N and P detection. We conclude that near infrared spectroscopy combines with feature selection and multiclass classification able to determine nitrogen and phosphorus.
  • Publication
    Donut Modes in Space Wavelength Division Multiplexing: Multimode Optical Fiber Transmission based on Electrical Feedback Equalizer
    ( 2021-03-01)
    Ghazi A.
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Syed Zulkarnain Syed Idrus
    ;
    Endut R.
    ;
    Ali N.
    ;
    Amphawan A.
    ;
    Fareed A.
    ;
    A.dawood
    ;
    Noori A.
    This study demonstrates the implementation of multi-input-multi-output (MIMO) transmission donut modes in space wavelength division multiplexing (SWDM) over multi-mode optical fiber (MMOF) and simulating the effect of mode coupling of the transmitted signal. However, during the data transmitted over MMF by using SWDM an issue is encountered, which is the inter symbol interference (ISI) due to mode coupling. ISI has been recognized as a major obstacle to high-speed data transmission. The signal processing in SDM of donut modes over MMOF with electrical feedback equalizer is used to improve the performance for increasing the bandwidth. A data rate 80 Gbit/s up for a distance of 1600 meters is achieved. SWDM topology was designed emitted from a spatial vertical cavity surface-emitting laser (VCSEL) through MMOF in conjunction with the configurations of electrical feedback equalizer. The parameters and values used in Opt-Sim simulation topology were listed. The performance measurement of this study based on bit-error rates (BER) and eye diagram before and after electrical feedback equalization were analysed.
  • Publication
    Rain-streaks Detection and Removal in Single Image Using Curvelet Transform
    ( 2019-12-01)
    Bahashwan A.A.
    ;
    Ehkan P.
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Safar A.M.
    ;
    Bahashwan M.A.
    ;
    Hafeezallah A.
    This study implements a new way to address the issue of rain streaks detection and elimination from a single picture based on the transform of Curvelet. This approach depends on a decomposing of the rainy image into different scales and sub-bands frequencies by using the curvelet transform. Features have been extracted from each sub-band frequency and the neural network will classify these features into "rain" or "non-rain" signatures. The reconstructed image is obtained without the sub-bands that have the rain signature. The findings from the experiments indicate that the proposed approach improves the visualizing quality as well as PSNR and outperforms previous rain removal algorithms.
  • Publication
    A Systematic review of Multi-Mode Fiber based on Dimensional Code in Optical-CDMA
    ( 2021-04-07)
    Ghazi A.
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Syed Zulkarnain Syed Idrus
    ;
    Mohd Rashidi Che Beson
    ;
    Daw. a
    ;
    Mahmood B.A.
    ;
    Fareed A.
    ;
    Zaenal M.U.
    ;
    Qasim N.H.
    ;
    Rafeeq R.M.
    This paper deals with optical code division multiple access (optical-CDMA) and provides a general analysis of multi-mode fiber (MMF). The purpose of this work is to classify the works in the literature that are related to Optical-CDMA based on MMF and to find the limitation of the researches done in this field. Several challenges that occur in the medium such as multiple-access interference (MAI), pulse dispersion (PD) and nonlinearity in optical fibers deteriorate system performances and become a major performance-limiting factor.