Rainfall Dynamics Over Two Indian Tropical Stations for Radio Communication

The influence of rainfall on radio wave propagation at frequencies above 10 GHz is crucial over ground to space radio links, especially in tropical regions because of the high intensity rainfall. This often makes direct-to-home; very small aperture terminal systems operating at these frequencies to be subjected to many fade occurrences due to heavy rain. In addition to annual and worst month’s cumulative statistics, dynamic characteristics of seasonal and diurnal variations, together with average event length and separation over the day are needed to give the detailed insights for system design. This paper presents the characteristics of rain distribution based on 5-year rainfall data over two locations in India. Rain intensities for the average year and the average worst months, and monthly and diurnal dynamic characteristics of rain events were obtained. The resulting rain intensities are also compared with the relevant ITU-R recommendations. These results are useful to estimate signal outages in a year over the region and for proper planning of radio-communication in the location.