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Progress In Electromagnetics Research
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RAINFALL RATE PROBABILITY DENSITY EVALUATION AND MAPPING FOR THE ESTIMATION OF RAIN ATTENUATION IN SOUTH AFRICA AND SURROUNDING ISLANDS

By P. A. Owolawi

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Abstract:
The paper describes the modelling of the average rainfall rate distribution measured at different locations in South Africa. There are three major aspects this paper addresses: to develop a rainfall rate model based on the maximum likelihood method (ML); to develop contour maps based on rainfall rate at 0.01% percentage of exceedence; and re-classification of the ITU-R and Crane rain zones for the Southern Africa region. The work presented is based on five-minute rainfall data converted to one-minute equivalent using a newly proposed hybrid method. The results are mapped and compared with conventional models such as the ITU-R model, Rice-Holmberg, Moupfouma and Crane models. The proposed rainfall rate models are compared and evaluated using root mean square and chi-square (χ2) statistics. Then re-classification of the rain zone using ITU-R and Crane designations is suggested for easy integration with existing radio planning tools. The rainfall rate contour maps at 0.01% percentage of exceedence are then developed for South Africa and its surrounding islands.

Citation:
P. A. Owolawi, "Rainfall Rate Probability Density Evaluation and Mapping for the Estimation of Rain Attenuation in South Africa and Surrounding Islands," Progress In Electromagnetics Research, Vol. 112, 155-181, 2011.
doi:10.2528/PIER10082504
http://www.jpier.org/PIER/pier.php?paper=10082504

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