Rain attenuation effects in considering the feasibility of stratospheric communication platforms for rural areas of South Africa.
Also known as High Altitude Platform Stations (HAPS), these systems employ unmanned or manned, solar or fuel energy airships or aircraft carrying payloads with transponders and antennas. These remote airships or aircraft offer a much more cost effective solution for coverage of certain regions including: urban, suburban, rural and other environments with low population densities. The Stratospheric Communications Platform (SCP) network offers a better solution than existing Cellular Radio Systems for telecommunication and multimedia services, with greater speed of transmission than even optical modes. It would be virtually impossible to construct land lines and microwave networks in remote, one thousand square-kilometre rural areas. There are other drawbacks to wired deployment as well. The cost of copper wire is astronomical, the terrain harsh and inaccessible and the population scattered. The aim of this dissertation is to illustrate that the use of a platform of this nature is suitable to the rural environment of South Africa. This work includes a case study to ascertain the feasibility of a high altitude platform approach to telecommunication service provision for rural areas. Realising its feasibility has led to an intensive study of rain attenuation. The specific attenuation calculated for a South African rural area (Ulundi) is compared to lTV values. A performance evaluation of the SCP has been done via a link budget calculation with the calculated attenuation values used as input parameters. The advantages of SCPs due to lower path loss, mobile power consumption and system cost are documented. A cellular network architecture is proposed and future investigations into station-keeping techniques, payload power and platform placement are discussed.