Performance Evaluation of Channel Switching Scheme for Packet Data Transmission in Radio Network Controller

W-CDMA (Wideband-CDMA) is expected to play a significant role in the radio access technology of third-generation mobile telecommunication systems. In second-generation systems, voice traffic from each user has been transmitted mainly via the dedicated transport (radio) channel. In addition, the third-generation systems will efficiently accommodate data traffic based on packet transmission in the shared common transport channel. Therefore, data traffic can be transmitted via one of two types of data channels: i.e., dedicated channels or common channels. However, the channel selecting/switching scheme has not been standardized; thus, system architectures and algorithms of channel-switching schemes in the RNC (Radio Network Controller) are dependent on its vendors, and network operators must determine the parameter settings related to channel selection. In this paper, we will deal with aspects of the architecture in detail, and propose possible algorithms for channel selecting/switching for fundamental reference systems which meet the specifications of the RNC. We will then evaluate our algorithms by means of simulations, and discuss the impact of parameter settings on performance, in terms of packet loss probability and utilization of dedicated channels. key words: IMT-2000, W-CDMA, RNC, Dedicated Channel, Common Channel