Comparison of packet scheduling algorithms focusing on user throughput in high speed downlink packet access

摘要

This paper compares by computer simulation the achievable throughput performance employing fast packet scheduling algorithm focusing on the throughput of each user in high speed downlink packet access (HSDPA). Three packet scheduling algorithms are employed: the maximum carrier-to-interference power ratio (CIR), proportional fairness (PF), and round robin (RR) methods. Simulation results elucidate that although the maximum CIR method achieves an aggregated user throughput within a cell higher than that using the PF and RR methods, the PF method is advantageous because it enhances the user throughput for a large number of access; users with a lower received signal-to-interference power ratio (SIR), who an located outside the normalized distance of 0.6-0.7 from a cell site (this corresponds to the area probability of 50-60% within the cell) compared to the maximum CIR method. Finally, we show that the average user throughput in a 2-path Rayleigh fading channel is reduced by approximately 30% compared to that in a 1-path channel due to severe multipath interference (MPI) and that the average user throughput is strongly affected by the total traffic produced within a cell, which is directly dependent on the number of users within a cell and the data size per packet call.