Rain Attenuation Factor in the Earth-Space Links of Tropical Regions

Yee Loo Foo

Abstract


Rain attenuation is an important factor to be considered in the Earth-space communication link budget, especially for regions that receive heavy rainfall, e.g. tropical regions. Inaccurate estimation of rain attenuation may result in broken or intermittent Earth-space links. The estimation of rain attenuation depends on many other factors. One of the important ones is the height from sea level within which raindrops is assumed present, i.e. rain height. International Telecommunications Union (ITU) recommends the ITU-R P.839-4 (09-2013) method for predicting rain height, and the ITU-R P.618-13 (12-2017) method for determining rain attenuation. Recently, some works claimed inaccuracy of these methods in the tropical regions, and proposed some modified methods. This paper aims to clarify the doubts. We determine the possible causes of inaccuracy, and then assess the impact of inaccurate estimation of rain height onto rain attenuation. As compared to the modified methods, we found that the rain height values calculated from ITU-R P.839-4 make more sense. It is likely that incorrectly represented formulas were used in some related works. Moreover, rain attenuation values obtained from ITU-R P.618-13 are resilient to the changes in rain heights. As a result, we advocate the use of the ITU-R P.839-4 and ITUR P.618-13 methods in the tropical regions.

Keywords


Attenuation; Radio Propagation; Radio Propagation Meteorological Factors; Rain;

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References


Recommendation ITU-R P.618-13 (12-2017): Propagation data and prediction methods required for the design of Earth-space telecommunication systems, 2017.

Recommendation ITU-R P.837-7 (06-2017): Characteristics of precipitation for propagation modeling, 2017.

Recommendation ITU-R P.838-3 (03-2005): Specific attenuation model for rain for use in prediction methods, 2005.

Recommendation ITU-R P.839-4 (09-2013): Rain height model for prediction methods, 2013.

R. Nalinggam, W. Ismail, M. J. Singh, M. T. Islam and P. S. Menon, “Development of rain attenuation model for Southeast Asia equatorial climate,” IET Communications, vol. 7, no. 10, pp. 1008-1014, July 2013.

M. A. N. Azlan, J. Din and H. Y. Lam, “Rain height information from TRMM precipitation radar for satellite communication in Malaysia,” Proceeding of the 2011 IEEE International Conference on Space Science and Communication (IconSpace), Penang, 2011, pp. 73-76.

J. S. Ojo, “Rain height statistics based on 0C isotherm height using TRMM precipitation data for Earth-space satellite links in Nigeria,” ISRN Atmospheric Sciences, 2014.

J. S. Ojo, O. L. Ojo and C. I. Joseph-Ojo, "Rain height information from TRMM precipitation radar and micro rain radar for radio communication studies in Nigeria,"2014 IEEE 6th International Conference on Adaptive Science & Technology (ICAST), Ota, 2014, pp. 1-5.

K. Okamoto, H. Sasaki, E. Deguchi, and M. Thurai, “Bright-band height statistics observed by the TRMM precipitation radar,” The Second TRMM International Science Conference, Nara, 9 Sep. 2004.

A. I. O. Yussuff and N. H. H. Khamis, “Comparative Analysis of Bright Band Data from TRMM and Ground Radar Data in Malaysia,” International Journal of Networks and Communications, vol. 3, no. 4, pp. 99-109, 2013.


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ISSN: 2180-1843

eISSN: 2289-8131