Anuar Mat Safar
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Preferred name
Anuar Mat Safar
Official Name
Anuar, Mat Safar
Alternative Name
Mat Safar, Anuar
Main Affiliation
Scopus Author ID
57193311430
Researcher ID
IYF-6674-2023

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  • Publication
    Implementation of particle swarm optimization and genetic algorithms to tackle the PAPR problem of OFDM system
    (IOP Publishing, 2020)
    A Abdalmunam
    ;
    Anuar Mat Safar
    ;
    MN Junta
    ;
    Norizan Mohamed Nawawi
    ;
    A Noori
    A multi-carrier modulation technique, which represented in this paper as orthogonal-frequency-division-multiplexing (OFDM), ensured wireless high-speed data transmission. The transmission of modulated symbols uses a large number of subcarriers in the OFDM system. Consequently, the OFDM signals have an extended dynamic range, or a high output power peak envelope fluctuation or high PAPR. To mitigate the PAPR, in this paper, we implement two algorithms to reduce the output power envelope fluctuation of the OFDM system, namely PSO and GA. Also, the PTS method and PAPR in OFDM systems difficulty described briefly. We present an OFDM system through the use of conventional PTS based on PSO and GA. The simulation result shows that both evolutionary approaches outperform the conventional PTS OFDM in-terms of reducing the Peak-to-Average-Power-Ratio (PAPR). Furthermore, the performance of the PSO algorithm is found to be better than GA in-terms of its simplicity and the time execution. On the other hand, the GA algorithm outperforms the PSO and the conventional OFDM, in terms of the PAPR reduction.
  • Publication
    A multilayers adaptive ALACO-OFDM for spectral efficiency improvement using PSO algorithm in visible light communication systems
    (De Gruyter, 2023)
    Aymen Abdalmunam Hameed
    ;
    Anuar Mat Safar
    ;
    Montadar Abas
    ;
    Junita Mohd Nordin
    ;
    Norizan Mohamed Nawawi
    In this paper, we propose a new adaptive layered asymmetrically-clipped optical orthogonal frequency division multiplexing (ALACO-OFDM) technique as a method to improve the spectral efficiency of optical system, especially visible light communication (VLC). Particle swarm optimisation (PSO)-based LACO-OFDM method is used for this purpose and the channel capacities are studied. Simulations using variable layers are carried out to validate the theoretical steps. The simulation results indicate that the ALACO-OFDM technique has significantly improve the spectral efficiency compared to previous techniques such as ACO-OFDM. Moreover, it is shown that channel capacities of different layers are significantly improved when electrical power is increased.
      2  25
  • Publication
    Performance enhancement of LACO-OFDM BER and PAPR using a K-means algorithm for a VLC system
    (Optica Publishing Group, 2023)
    Junita Mohd Nordin
    ;
    Aymen Abdalmunam Hameed
    ;
    Anuar Mat Safar
    ;
    Norizan Mohamed Nawawi
    Layered asymmetrical clipped optical-orthogonal frequency division multiplexing (LACO-OFDM) enhances spectral efficiency by mandating the use of a K-means algorithm in LACO-OFDM (KLACO-OFDM), which enables efficiency gains to nearly double by modulating odd and even subcarriers. The traditional receiver is not sufficiently sophisticated enough to exploit the full potential of LACO-OFDM, thereby restricting its performance. In this paper, a K-means algorithm was used to increase the spectral efficiency of LACO-OFDM by integrating machine learning to cluster the inward signal such that the original locations of the received constellations can be retrieved. A K-means algorithm is used for assigning the received constellation points into their clusters of the ordinary quadrature amplitude modulator constellation points. The new mathematical framework in the proposed scheme is structured to analyze the PAPR and BER performance of LACO-OFDM systems that have been derived. The K-means algorithm development in LACO-OFDM (KLACO-OFDM) has also reduced the intersymbol interference, hence improving the spectral efficiency of LACO-OFDM compared with the conventional system in visible light communication (VLC) systems. BER gains were about 1.2–1.6 dB at 10−3 BER value, which rises from 1.4 to 2 dB for a 10−4 BER value because a lower BER facilitates precise estimation.
      1  11