Engineering Physics

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Vertical Radio Refractivity Profile for Calabar in the Southern Region of Nigeria

Received: 25 October 2016    Accepted: 03 January 2017    Published: 30 January 2017
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Abstract

In this paper, six months Radiosunde data for Calabar in the Southern region of Nigeria is used to model vertical refractivity profile. Calabar is located in Cross River State 4°57’North in latitude and 8°19'East in longitude which is in the South South region of the country. The Radiosunde data is obtained from Nigerian Meteorological Agency (NIMET). Particularly, cubic trendline model is developed for each of the six months to predict the vertical profile of refractivity in the lower atmosphere (< 150 m) above sea level). The model can be used to predict the refractivity at any height between 0 m and 150 m. Also, the model can enable the determination of point refractivity gradient which requires the refractivity at 0 m and at 65 m above sea level. Sample point refractivity gradient for the month of January. In the month of January, it was found that the point refractivity gradient is 124.278 N-units.

DOI 10.11648/j.ep.20170101.14
Published in Engineering Physics (Volume 1, Issue 1, June 2017)
Page(s) 21-26
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This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Refractivity, Refractivity Gradient, Vertical Profile, Point Refractivity, Refractive Index

References
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[2] Asiyo M. O. (2013). Characterisation and modeling of effects of clear-air on multipath fading in terrestrial links. Unpublished masters dissertation, University of Kwazulu-Natal,South Africa.
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[10] Basu, S., McCrae, J., Pollock, Z., He, P., Nunalee, C., Basu, S.,... & Fiorino, S. (2015, June). Comparison of atmospheric refractive index gradient variations derived from time-lapse imagery and mesoscale modeling. In Propagation through and Characterization of Distributed Volume Turbulence and Atmospheric Phenomena (pp. PM1C-4). Optical Society of America.
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Author Information
  • Department of Computer Engineering, Michael Okpara University of Agriculture, Umudike, Nigeria

  • Department of Electrical, Electronic and Computer Engineering, University of Uyo, Uyo, Nigeria

  • Department of Electrical, Electronic and Computer Engineering, University of Uyo, Uyo, Nigeria

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  • APA Style

    Ngwu Chinyere Rosemary, Ozuomba Simeon, Okon Abasiama Colman. (2017). Vertical Radio Refractivity Profile for Calabar in the Southern Region of Nigeria. Engineering Physics, 1(1), 21-26. https://doi.org/10.11648/j.ep.20170101.14

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    Ngwu Chinyere Rosemary; Ozuomba Simeon; Okon Abasiama Colman. Vertical Radio Refractivity Profile for Calabar in the Southern Region of Nigeria. Eng. Phys. 2017, 1(1), 21-26. doi: 10.11648/j.ep.20170101.14

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    AMA Style

    Ngwu Chinyere Rosemary, Ozuomba Simeon, Okon Abasiama Colman. Vertical Radio Refractivity Profile for Calabar in the Southern Region of Nigeria. Eng Phys. 2017;1(1):21-26. doi: 10.11648/j.ep.20170101.14

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  • @article{10.11648/j.ep.20170101.14,
      author = {Ngwu Chinyere Rosemary and Ozuomba Simeon and Okon Abasiama Colman},
      title = {Vertical Radio Refractivity Profile for Calabar in the Southern Region of Nigeria},
      journal = {Engineering Physics},
      volume = {1},
      number = {1},
      pages = {21-26},
      doi = {10.11648/j.ep.20170101.14},
      url = {https://doi.org/10.11648/j.ep.20170101.14},
      eprint = {https://download.sciencepg.com/pdf/10.11648.j.ep.20170101.14},
      abstract = {In this paper, six months Radiosunde data for Calabar in the Southern region of Nigeria is used to model vertical refractivity profile. Calabar is located in Cross River State 4°57’North in latitude and 8°19'East in longitude which is in the South South region of the country. The Radiosunde data is obtained from Nigerian Meteorological Agency (NIMET). Particularly, cubic trendline model is developed for each of the six months to predict the vertical profile of refractivity in the lower atmosphere (< 150 m) above sea level). The model can be used to predict the refractivity at any height between 0 m and 150 m. Also, the model can enable the determination of point refractivity gradient which requires the refractivity at 0 m and at 65 m above sea level. Sample point refractivity gradient for the month of January. In the month of January, it was found that the point refractivity gradient is 124.278 N-units.},
     year = {2017}
    }
    

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  • TY  - JOUR
    T1  - Vertical Radio Refractivity Profile for Calabar in the Southern Region of Nigeria
    AU  - Ngwu Chinyere Rosemary
    AU  - Ozuomba Simeon
    AU  - Okon Abasiama Colman
    Y1  - 2017/01/30
    PY  - 2017
    N1  - https://doi.org/10.11648/j.ep.20170101.14
    DO  - 10.11648/j.ep.20170101.14
    T2  - Engineering Physics
    JF  - Engineering Physics
    JO  - Engineering Physics
    SP  - 21
    EP  - 26
    PB  - Science Publishing Group
    SN  - 2640-1029
    UR  - https://doi.org/10.11648/j.ep.20170101.14
    AB  - In this paper, six months Radiosunde data for Calabar in the Southern region of Nigeria is used to model vertical refractivity profile. Calabar is located in Cross River State 4°57’North in latitude and 8°19'East in longitude which is in the South South region of the country. The Radiosunde data is obtained from Nigerian Meteorological Agency (NIMET). Particularly, cubic trendline model is developed for each of the six months to predict the vertical profile of refractivity in the lower atmosphere (< 150 m) above sea level). The model can be used to predict the refractivity at any height between 0 m and 150 m. Also, the model can enable the determination of point refractivity gradient which requires the refractivity at 0 m and at 65 m above sea level. Sample point refractivity gradient for the month of January. In the month of January, it was found that the point refractivity gradient is 124.278 N-units.
    VL  - 1
    IS  - 1
    ER  - 

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