On High Altitude Platforms (HAPs) UMTS-HSDPA

In this work, the performance of HAPs (high altitudes platforms) UMTS HSDPA (high speed downlink packet access) is studied for different HAPs height h, different cells radius R and two directions (0deg and 30deg) within the cell. It is noticed that, for urban zone users, the effective range is lower than the effective range for users in rural zones. Also it is noticed that in rural zone, the HSDPA mode can support the modulation 64QAM which is a modulation scheme out of the HSDPA standard. When the number of users is increased to two, it is noticed that, only the QPSK modulation can be used when the non-orthogonality factor phi is 0.5 (users are in urban zones)