Delay Characterization of Rateless Codes in Wireless Ad Hoc Networks

Unlike earlier works on rateless codes that mostly considered finite networks or ignored the traffic dynamics, this paper focuses on the end-to-end delay performance of rateless codes in large-scale wireless ad hoc networks with traffic dynamics. Specifically, the end-to-end delay is divided into two parts, namely the packet waiting time before transmission and the transmission time, whose statistical distributions are given by exact results as well as simple yet accurate approximations. This way, the statistics of the end-to-end delay are fully investigated. The proposed analytical framework and the end-to-end performance metric help obtain more insights on the role of scheduling, queueing, and coding scheme in practical networks. The approximations are verified to be effective and reliable through simulations. Overall, the results show the significant benefits of rateless codes relative to the fixed-rate codes in terms of the end-to-end delay performance.