Source and Channel Coding Adaptation for Optimizing VoIP Quality of Experience in Cellular Systems

Abstract

Quality of Experience (QoE) reflects the customer's perception of service, and is extremely important for operators. In VoIP service, variety of factors will affect customer's QoE, e.g. source data quality and the transmission channel condition. In cellular systems, although higher level of source coding will improve QoE, more radio resource will be consumed and thus degradation of system capacity will be caused. On the other hand, lower level of modulation and coding can ensure the data delivery, but will lead to more consumption of radio resource. In this paper, to solve these problems in multi-user cellular systems, the source coding quality and channel coding levels are jointly considered according to customer's QoE. In the source and channel coding adaptation, customers with over qualified QoE will sacrifice some radio resource to improve the under guaranteed QoE of others, or increase the system capacity. The simulation shows that the algorithm can effectively balance the utility of limited radio resource and increase customer's satisfaction ratio and system capacity.