HSDPA Performance in a Mixed Traffic Network

One of the advantages in an existing WCDMA network is that HSDPA (high speed downlink packet access) can be operated within an existing Release 4 (Release ´99) 5 MHz band, thus allowing for sharing the power amplifier and spreading codes at the Node-B between the HS-DSCH (high speed downlink shared channel) and the Release 4 downlink channels (DCHs). In this paper, we investigate the throughput performance of HSDPA in a network, in which also Release 4 traffic is present by utilizing a system level modeling of the HSDPA transmission if a Rake receiver is used, together with a coarse modeling of the Release 4 performance. By numerical simulations, we are able to deduce the optimum power split between HSDPA and Release 4 to maximize the overall cell throughput. The obtained results offer a more sophisticated understanding of the HSDPA network performance, and can be used by network operators for cell operation planning.