Performance evaluation of Network Coding-based convergecast in realistic wireless sensor networks

Network Coding has attracted significant attention in recent years, and it has been widely applied in broadcast, multicast and unicast. Nevertheless, the study on network coding in convergecast is still in the theoretical analysis and the simulation stage. In order to investigate the network coding gain of convergecast in realistic wireless sensor networks, a network coding-based convergecast scheme is realized in this paper. The experiment is conducted in the basic size of convergecast whose size is limited below four, which is for the purpose of eliminating as much interference from the large size of convergecast network as possible. Performed in traditional convergecast scheme and network coding convergecast scheme, the experiment on collection rate and energy consumption are evaluated under different link delivery ratios and scales of convergecast network. The experiment results show that network coding is certain to introduce benefit in the case of poor link equality. However, it is inferior to the traditional scheme when the wireless link delivery ratio is high enough due to the conscious overhearing and the prerequisite of successful decoding.