Markov models for the physical layer block error process in a WCDMA cellular system

We investigate the possibility of using Markov chains to model the error process in the data blocks delivered by the physical layer of a WCDMA (wideband code division multiple access) cellular system. Starting from the results on the error statistics obtained from a suitable simulation tool, which jointly performs system and link level analysis, we first classify the users on the basis of performance level and burstiness, then we provide some guidelines for the design of Markov models in the different system and channel conditions. The performance of an ARQ (go-back N) protocol at the link layer is taken as a reference to test the reliability of the proposed models. It is shown that the perspective of using simple error models in the analysis of upper-layer protocol is feasible in many cases.