UMTS-HSDPA in High Altitude Platforms (HAPs) communications with finite transmitted power and unequal cell’s load

In this paper, the performance of HAPs (High Altitude Platforms) UMTS HSDPA (High Speed Downlink Packet Access) is studied for different scenarios and two directions (0° and 30°) within the cell where the network under study is assumed to have 61 cells. It is concluded that, for urban zone users, the effective range is lower than the effective range for users in rural zones. It is shown that in rural zones, the HSDPA mode can support the modulation 16QAM with 7/8 code rate when cells are not fully loaded. For fully loaded rural cells, the 16QAM modulation scheme with code rate of 7/8 cannot be supported. Also, it is noticed that, in urban zones, HSDPA mode can support 16QAM with code rate of 1/2 and QPSK modulation schemes when cells are not fully loaded. For fully loaded urban cells, only QPSK with code rate of 1/2 can be supported.