This work investigates fade dynamics of satellite communication systems in equatorial heavy rain region based on a one year of Ku-band propagation measurement campaign carried out in Universiti Teknologi Malaysia (UTM), Johor, Malaysia. First order statistics of rain attenuation are deduced and the results are found to be in good agreement with those obtained from other beacon measurements gathered within the same area (Kuala Lumpur). Moreover, the fade duration and slope statistics of the satellite signal variations are also carefully derived and subsequently compared with the ITU-R recommendation model. Such information is useful for the system operator and radio communication engineer for the design of appropriate fade mitigation techniques as well as the quality of service that could be offered to the user (according to the time interval for a typical day). Further evaluation on the performances of several ITU-R models in the heavy rain region are needed based on the measurement database available of this climatic region. 1. Introduction In satellite communication links, rain attenuation is the dominant impairment especially for frequency above 10？GHz particularly in tropical and equatorial regions. Precipitation causes attenuation due to scattering and absorption of the electromagnetic energy and it leads to significant performance degradation. Consequently, Ku-band broadcasting services are affected by link outage especially during time-critical transmission such as real-time news and sport events. The probable duration of rain fade, the time of day when it is likely to occur, and how frequently it happens are all important aspects for the design of satellite services [1]. In order to make operation of the satellite systems feasible at frequencies above 10？GHz, appropriate Propagation Impairment Mitigation Techniques (PIMTs) are required such as power control, link diversity, and adaptive modulation scheme [2, 3]. In general, the proper design and implementation of PIMTs require the knowledge of first and second order statistics of rain attenuation [4]. First order statistics refer to cumulative distribution of rain attenuation and rainfall rate while second order statistics describe the dynamic characteristics of rain attenuation such as fade duration, fade slope, and inter-fade-interval. Fade duration and fade slope are referred to the time interval between two successive crossings above the same attenuation threshold and to the rate of change of attenuation with time, respectively [5]. The knowledge of second order statistics for rain
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