Rain fade and Ka-band Spot Beam Satellite communication in India

Abstract

The Ka-band (20–30 GHz) frequency spectrum has recently gained attention for satellite communication. High Definition Television (HDTV), which needs a much larger bandwidth for transmission, coupled with the current demand for hundreds of television channels and the growth in Internet communications through Direct-To-Home (DTH), is resulting in a communications bandwidth shortage. One tool being used to address this problem is Satellite Spot-Beams. To design effective satellite communication system operation at extremely high frequency band (Ka and higher bands), the effect of meteorology is important compared to Ku-band frequencies. Keeping view of the socio-economic and geographic diversities of India, Propagation studies are essential for estimation of attenuation, so that Ka-band satellite links operating in different parts of Indian region can be registered appropriately. This paper analyzes Ka-band satellite communications link availability in various geographical separated spot beams in India using statistical data. This paper proposes 16 spot-beam locations to cover Indian main land. It is based on global rain models integrated with the link budget. The global Crane model and ITU-DAH rain model allow us to examine major system design issues encountered in Ka-band satellite communications that are susceptible to propagation impairments. This system is flexible enough to increase power on specific transmissions when needed to compensate for local weather conditions.