Effect of Antenna Beam Pattern and Layout on Cellular Performance in High Altitude Platform Communications

摘要

High Altitude Platforms may offer high spectrum efficiency by deploying multi-beam, multi-cell communications networks. The properties of the antennas carried by the HAP payload are key to the effective exploitation of these benefits. This paper compares different models for the antenna sidelobe region and quantifies, in each case, the carrier to interference ratio for a 3 channel re-use plan. Networks of 121 and 313 cells are compared. We show how the ITU recommended pattern for the 47/48 GHz band leads to pessimistic results compared to an adapted pattern which fits that of measured data for an elliptic beam lens antenna. The method is then extended to consider other radiation patterns. Spectrum sharing issues are explored with reference to further ITU recommendations and comparison with measurement data. Finally, an ITU type cellular layout which uses the same antenna for each cell is compared to an alternative hexagonal layout where each cell has equal size.