Investigation of low clouds attenuation on earth space path for some West-Africa stations

The study investigate the contribution of low clouds, to signal fade rate, at Ka band in the satellite communication links on earth-space path(s) to NigComSat 2, from three tropical locations in West Africa. Extracted cloud cover statistical data such as average cloud amount, average base height, and frequency of occurrence, were used to obtain the monthly variations and seasonal variations for Lagos (6.55°, 3.35°), Bouake (7.73°, -5.07°) and Bamako (12.53°, -7.95°). Cloud attenuation statistics were computed for each of the three stations for their respective uplink and downlink. The uplink and downlink attenuation ranges between about 0.2 to 1.6 dB and 0.1 to 0.8 dB respectively for Lagos; for Bouake between 0.005 to 0.035 dB and 0.003 to 0.016 dB respectively; finally, for Bamako between about 0.2 to 2 dB and about 0.1 to 1 dB respectively. The stations downlink attenuation sets of values are generally about twice their corresponding uplink attenuation values.