Malaysia is located in tropical and equatorial region which has a high amount of annual rainfall, particularly during monsoon seasons. There is a need for a reliable rain rate model for the purpose of planning and designing of satellite communication systems; management of water resources, agricultural activities, and flooding, as well as to assess the impact of climate change. Most of the rain rate data provided by meteorological agencies have longer integration time which is higher than one minute. Therefore, conversion of higher integration time rain rate data to one-minute rainfall rate plays an important role. Due to the fact that most of the existing models were developed based on temperate climates, developing the conversion product based on Malaysia climate which has high intensity rainfall is mandatory in order to improve the accuracy of conversion evidence in Malaysia. This book discusses the scientific effect of various integration time (60 minutes, 30 minutes and 10 minutes) rain rate to one-minute rain rate conversion model for Malaysia climate. The estimation of one-minute rain rate is done for the purpose of designing telecommunication systems in Malaysia.