Link quality-aware cut-off prioritisation strategy for GSM/GPRS networks with link adaptation

In this paper, the system level performance (teletraffic analysis) of a GSM/GPRS network where speech and data services coexist is analytically evaluated. In our work, link adaptation for both speech and data services, is considered in the system capacity assessment. For speech service, half- and full-rate vocoders are considered in the analysis. For data services, only those coding schemes that are currently used in practical GPRS systems are used in our analysis: CS-1 and CS-2. Also, a link quality-aware triple threshold reservation (LQA TTR) scheme is proposed. In LQA TTR, preference is given to data users on the good quality zone (CS2) because, on average, they require less time to be served relative to data users on the bad quality zone (CS-1). Numerical results show that the proposed LQA TTR scheme effectively reduces call blocking probabilities relative to the conventional multiple channel reservation strategy.