Notice of Retraction Estimation of multipath propagation and fade margin over Coastal area

Falodun S. E., Omotoso E. T., Ashidi A. G.

Abstract


Notice of Retraction

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After careful and considered review of the content of this paper by a duly constituted expert committee, this paper has been found to be in violation of APTIKOM's Publication Principles.

We hereby retract the content of this paper. Reasonable effort should be made to remove all past references to this paper.

The presenting author of this paper has the option to appeal this decision by contacting ij.aptikom@gmail.com.

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Atmospheric weather parameter is dynamic in nature, hence the need for continuous investigation of the anomalous propagation phenomenon. The coastal region is more unique in its characteristics due to the rapid and continuous variation in the weather parameters. This paper presents the results from 10 years (2006 – 2015) of reanalysis data of meteorological parameters (temperature, relative humidity and atmospheric pressure) obtained from European Center for Medium-Range Weather Forecasts (ECMWF). The data covers some selected stations in the coastal region of Nigeria namely: Port-Harcourt, Warri, Calabar, Arogbo, Oron, Yenagoa and Lagos Island at four synopsies hours of the day (6 hrs, 12 hrs, 18 hrs and 24 hrs). The resolution of the ECMWF data is 0.25 by 0.25. Radio refractivity, refractivity gradient, point refractivity and geoclimatic factor are estimated from the data. Subsequently, the results were used to deduce percentage of fade depth exceedance. The overall resultsa will assist to ascertain the level of signal degradation due to multipath fading and fade depth over the coastal regions of Nigeria


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DOI: https://doi.org/10.11591/APTIKOM.J.CSIT.124

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