Voice QoS in third-generation mobile systems

摘要

We analyze voice quality and system performance innthird-generation mobile communication systems. We argue that in thesennetworks that are expected to integrate voice, data, and multimedianservices, the transport network can no longer be considered as anlossless transparent traffic channel. Rather, proper dimensioning isnneeded even for plain voice services. Furthermore, the efficientnutilization of the network resources shared by voice and data trafficnrequires sophisticated traffic management in the statisticalnmultiplexing environment. The contribution of the paper is twofold:nfirst, voice quality in the cellular transport network is analyzed andnnetwork dimensioning criteria are derived. Second, building on advancesnreported in the literature and taking into consideration currentnstandardization activities, a joint performance model is established fornthe air interface (AI) and the transmission network (TN) allowing fornthe analysis of end-to-end service performance within a uniformnframework. To demonstrate the applicability of this model, we point tonsome performance problems in the multiservice environment and suggestnand evaluate traffic management actions to overcome these