Stratospheric Propagation And HAPs Channel Modeling

Abstract: High Altitude Platform Stations (HAPs) are communication facilities situated at an altitude of 20 to 50 km and at a specified, nominal, fixed point relative to the Earth. They are mostly solar-powered, unmanned, and remotely-operated. These platforms have the capability of carrying multipurpose communications relay payload, which could be in the form of full base station or, in some cases, a simple transponder as is being used in satellite communication systems. Services and applications that will be provided and supported by HAPs include; future generation mobile telephony, broadband wireless access, navigation and positioning systems, remote-sensing and weather observation/monitoring systems, etc. HAPs are billed to be the next big thing in providing infrastructure for wireless communications and there are several ongoing and exciting research works into various aspects of this emergent technology. Expectedly, the need to predict the channel quality and analyze the performance evaluation of such stratospheric propagation has generated quite a few models. This thesis work provides some insight into this new aspect of wireless communications in terms of the need for a new system, its benefits, challenges services provided and applications supported. Finally, 4 channel models developed for the HAPs environment are reviewed and one that has been found, upon analysis, to be broad-based and rather realistic in its results is implemented in order to evaluate the system performance using the bit error rate (BER).