ABSTRACT

This study presents the performance improvement of signal over Ku-band satellite communication using fuzzy logic system. The satellite communication is an essential part of telecommunication systems which carries a large amount of data and telephone traffic in addition to television signals. At high frequency, satellite links are more sensitive to signal fades due to rain, especially in the tropical region. Rain attenuation can have a distorting effect on the quality of service (QoS) at higher frequencies that lead to excessive digital transmission error. This loss of signal is commonly referred to as signal attenuation. Rainfall data was obtained from the Nigerian Meteorological Agency for a period of ten (10) years for the purpose of estimating attenuation using ITU-R and DAH models. Umuahia geographical location was considered as the choice of environment. Data was also obtained from Modern Communications Limited which was used to calculate Bit-error-rate and Network throughput. A developed model was used to interact with the input parameters to improve the quality of signal. The fuzzy logic system was added to mitigate rain attenuation in order to guarantee a certain level of signal quality. The simulated results show the effectiveness of the developed model and its ability to improve QoS over Ku-band satellite communication in spite of rain attenuation. Netharn et al were able to improve the signal quality by 20.27% whereas the developed model in this Thesis was able to improve the quality of the satellite signal by 63.9%.