Theses & Dissertations

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https://hdl.handle.net/20.500.14170/209

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Browsing Theses & Dissertations by Subject "Agricultural waste"
  • Publication
    Electrical and mechanical properties characterization of agricultural waste/sand composites for WLAN antenna design
    ( 2021)
    Nurul Ain Zulkifli
    Rice husk, rice straw, sugarcane bagasse and dried banana leaves are the residues product used in this research. In most places, these residues possess no commercial value and are disposed in various ways, including illegal open burning, which causes pollution. To overcome this problem, these agricultural waste materials have potential to be used as a dielectric resonator material for dielectric resonator antenna. The existing dielectric material used for dielectric resonator antenna consume high price compared with agricultural waste material. Besides, this reduces the usage of hazardous inorganic materials, and at the same time minimizes pollution and recycles organic waste materials. These composites will be first characterized in term of their electrical and mechanical properties as potential to be used for antenna application. This starts with the preparation of the sample by grinding each of the materials into fine particle. Then, the residues powders were mixed together with the resin and hardener agent. After that, the mixture is then placed into a square mold and been left for two days in a room temperature to ensure the mixture become hardened. Next, the electrical parameter measurements like dielectric properties were studies to determine the performance of dielectric constant and loss tangent. The performance of the dielectric properties of the sample waste materials was studied in the range of 1 GHz until 3 GHz and the samples were measured by using the open ended coaxial probe techniques. The high reading of dielectric constant and low loss tangent of a material are suitable used for antenna application. Besides that, the mechanical properties of the agricultural waste sample undergo 2 analyses consist of tensile strength test and morphology analysis. Tensile strength indicates the ability with stand load or tension applied into the dielectric material and morphology analysis is used to analyze the composite microstructure. Furthermore, this research is proceeds by designing the microstrip patch antenna for Wireless Local Area Network (WLAN) application at frequency 2.45 GHz by using Computer Simulation Technology (CST) software. Then, this process is continued by designing microstrip patch antenna with single and double dielectric material as dielectric resonator antenna (DRA) at frequency 2.45GHz for antenna miniaturization purpose. Then, the three antennas were fabricated, and the experimental results were accomplished using PNA network analyzer where the measured results agree well with the simulated results. The results of reflection coefficients S11, and results of gain for microstrip patch antenna with single and double dielectric resonator material after being miniaturized were same as the original microstrip patch antenna. Hence the objective to miniaturize the antenna without degrading the performance of reflection coefficient and gain is achieved. In overall, the dried banana leaves with sand sample found to be the best dielectric material to be used for antenna application as dielectric resonator antenna.
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