Diligent inquiry of lower level atmospheric clouds attenuation on earth space path links for certain Indian localities

Abstract

This paper presents the effect of lower level atmospheric clouds for originating atmospheric attenuation, at Ku, K and Ka bands in the satellite communication path links. The clouds which are of low altitude (Cumulus, Cumulonimbus, Stratus, Nimbostratus) are majorly responsible for cloud attenuation. The physical cause of cloud attenuation is the total liquid water content. The details of the various existing cloud attenuation models and their advantages and disadvantages has been discussed. In this study, the attention has been calculated by using most popular, recent and well recognized models (e.g., Dissanayaka Allnut Haidara model, Salonen and Uppala model and International Telecommunication Union-Recommendations model). In this paper variation of frequency with cloud delay, Height of the cloud versus cloud attenuation, elevation angle versus cloud attenuation of four different low level clouds, frequency versus slant path attenuation, elevation angle and temperature versus cloud attenuation, cloud liquid water content versus cloud attenuation by using different models has been calculated, and comparison of different cloud attenuation has been reported. From the analysis, it has been realized that for the prediction of cloud attenuation in the frequency range of 10–60 GHz, a 0 °C effective cloud temperature must be used for frequencies below 40 GHz and a −1 °C effective cloud temperature must be used for frequencies above 40 GHz. In this paper it has been proved that SU-model values are very nearer to ITU-R model values.