A joint physical layer multi-state rate adaptation and cost-function based MAC scheduling for the WCDMA system

Abstract

This paper presents a joint physical layer multi-state rate adaptation algorithm combined with MAC scheduling for the WCDMA system. According to the cumulative distribution function of the received signal to noise ratio (SNR), our proposed multi-state rate adaptation scheme determines a set of state transition thresholds to dynamically adjust spreading factors via the transport format (TF) selection procedures in the MAC layer. Moreover, we proposed a cost function based TF selection procedures to incorporate many important factors in both the MAC layer and physical layer, such as service priority, buffer occupancy, and radio link quality. Through a cross-layer design in both the two layers, the proposed cost function based transport format selection procedures can effectively enhance throughput, save power, and guarantee service fairness for the WCDMA system.