• 제목/요약/키워드: total path loss ($L_{PL}$)

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Exploiting W. Ellison model for seawater communication at gigahertz frequencies based on world ocean atlas data

  • Tahir, Muhammad;Ali, Iftikhar;Yan, Piao;Jafri, Mohsin Raza;Jiang, Zexin;Di, Xiaoqiang
    • ETRI Journal
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    • 제42권4호
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    • pp.575-584
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    • 2020
  • Electromagnetic (EM) waves used to send signals under seawater are normally restricted to low frequencies (f) because of sudden exponential increases of attenuation (𝛼) at higher f. The mathematics of EM wave propagation in seawater demonstrate dependence on relative permeability (𝜇r), relative permittivity (𝜀r), conductivity (𝜎), and f of transmission. Estimation of 𝜀r and 𝜎 based on the W. Ellison interpolation model was performed for averaged real-time data of temperature (T) and salinity (S) from 1955 to 2012 for all oceans with 41 088 latitude/longitude points and 101 depth points up to 5500 m. Estimation of parameters such as real and imaginary parts of 𝜀r, 𝜀r', 𝜀r", 𝜎, loss tangent (tan 𝛿), propagation velocity (Vp), phase constant (𝛽), and α contributes to absorption loss (La) for seawater channels carried out by using normal distribution fit in the 3 GHz-40 GHz f range. We also estimated total path loss (LPL) in seawater for given transmission power Pt and antenna (dipole) gain. MATLAB is the simulation tool used for analysis.