Worldwide techniques for predicting the multipath fading distribution on terrestrial LOS links: comparison with regional techniques

A revised worldwide method has been recommended by the Radiocommunications Sector of the International Telecommunication Union (ITU-R) in Recommendation ITU-R 530-8 for predicting the deep-fading distribution due to multipath propagation in the average worst month on VHF-EHF terrestrial line-of-sight links. This paper presents detailed testing results for the revised method on a 239-link database from 22 countries around the world in comparison with results for the leading regional methods still frequently used by some link designers for worldwide applications (viz., the Barnett-Vigants (1972, 1970) method of the United States and the Morita (1970) method of Japan). An evaluation of the form of the prediction equation is given for the revised and previous ITU-R methods and several regional methods. The revised ITU-R method is shown to perform significantly better than the other methods for both overland and coastal/overwater links.