Empirical conversion process of rain rate distribution for various integration time

Rain attenuation can have a serious impact on the availability of radio communication services operating in the frequencies above 10 GHz. For higher frequencies, more rain impairments occur on the communication links. In order to predict reliable rain attenuation for a given location, an appropriate distribution of rainfall rate for the site is required. And further more, the distribution is needed to be derived from long-term (typically more than 10 years) measured data with 1-minute integration time. Unfortunately, it is not impossible to analyse long-term measured 1-minute rainfall data. Since rainfall data with more than 10-minute integration time are available in Korean Meteorological Agency, an appropriate conversion process which is appropriate to predict distribution of one-minute rainfall rate from various integration data is required. This paper proposes an appropriate conversion process of time probability of one-minute rainfall rate from that of other integrated rainfall rate. Based on 2-year rain-rate measurements conducted by ETRI, distributions of rainfall rate with 1-, 10-, 20-, 30-, 60-minute integration time are analysed, and relationships between 1-minute and other rainfall data are suggested in this paper. In addition, comparisons with some existing conversion methods such as Canadian, French, and Japanese method, are also performed, and a conversion method that is most appropriate to the ETRI measurement results is discussed.