Testing of Conventional Antennas for High Altitude Airborne Cellular Base Stations

Abstract

Using a conventional antenna system to obtain continual mobile communication coverage over two or more disparate regions from an airborne platform can be problematic. This is due to multiple parameters that affect the resulting signal spatial structure and signal gain observed from the mobile ground users, to include power, multipath mitigation, Doppler impact, spatial diversity, and interference suppression inefficiencies. A WB-57 high altitude research aircraft, designed to serve as a relay and control platform for military communications, employed a conventional antenna system coupled with a code division multiple access (CDMA) base station aimed at increasing coverage areas of mobile ground users in remote locations. This paper will analyze the measured results; coverage area (antenna pattern), link budget, pilot power, and Doppler impact, of the WB-57 aircraft utilizing a conventional antenna system joined with a QUALCOMM deploy able base station (QDBS) above 50,000 feet flying in a designated orbital pattern. Additionally, an investigation into conventional antenna systems and smart antennas systems will be conducted in order to determine the optimal antenna system selection for the WB-57 application to obtain continual coverage while airborne in a designated orbital pattern.