A multimedia transmission control algorithm based on cross-layer design in UMTS networks
The performance in the air interface of 3G/UMTS (Universal Mobile Telecommunications System) network is enhanced by the introduction of many advanced functionalities including ARQ (Automatic Repeat Request), HARQ (Hybrid ARQ) and AMC (Adaptive Modulation and Coding). Most existing TFRC (TCP-Friendly Rate Control)-based algorithms designed for wired-wireless heterogeneous networks fail to adapt to these advanced functionalities which results in degradation of performance. This paper proposes a novel cross-layer streaming transmission control algorithm WATC (Wireless-loss Aware Transmission Control) which makes use of the ARQ information to estimate the quality of wireless channels and improve the measurement of delay with the help of RLC (Radio Link Control) sublayer. WATC distinguishes wireless loss from congestion loss by the estimation of the quality of wireless channel and adjusts the sending rate according to the quality of wireless links and the tendency of delay variation. Simulation results show that WATC outperforms existing TFRC-like schemes in terms of loss rate control and throughput, while maintaining high throughput and fairness in multi-flow scenarios.
cross-layer design umts rate control congestion control