A Markovian Model for HSDPA TNL Congestion Control Performance Analysis

High speed downlink packet access (HSDPA) is an extension of the universal mobile telecommunication system (UMTS) technology of 3GPP Rel-99, with the objective of increasing the data rate and also reduce the latency in the downlink. The focus of this study is to develop an analytical model for HSDPA congestion control (CC) performance analysis. Often the transport network layer (TNL) is congested in HSDPA networks which degrades the overall HSDPA performance. The congestion control and detection algorithms are implemented in the Node B and RNC in order to minimize system congestions. There are several simulation based investigations carried out so far for the performance analysis of such algorithms. An analytical model which is based on the Embedded Markov chain with multiple departures (EMC-MD) is developed to analyse the effect of CC for the HSDPA performance. This analytical model includes all the important functionalities of the congestion control at TNL level. This paper also shows that the results from the analytical model are in agreement with the simulation results and that the analytical model can be effectively used to analyse the effect of parameters on performance of the HSDPA network and can be used dimensioning of the parameters.