Energy consumption in wireless sensor networks for network coding structure and ARQ protocol

Maximizing the lifetime of sensor networks is a major challenge. In a sensor network, the nodes communicate with each other to pass the information to a data sink. These nodes have limited energy resource, and to increase the lifetime of the network, it is necessary to design communication protocols which aim at reducing the consumed power. Several advanced communication protocols for sensor networks have been already proposed in order to optimize system performance using the BER criterion. We can classify them mainly in two categories: those which are based on network coding by inserting relays between sensors and destination, and those which use ARQ protocols. In this paper we compare these different solutions using a new criterion: the consumed power. The goal is to obtain a conclusion on the judicious choice of the protocol according to the range of SNR´s in a context of small network (we consider the BAN context for example). The simulation results show that above a given threshold SNR ARQ protocols outperform network coding solution and we are able to accurately predict this threshold value. Furthermore, we proposed a new transmission protocol named HCVD (Horizontal Correction Vertical Detection) protocol, which is a new protocol combining network coding and ARQ protocol and which exhibits the best tradeoff BER performances/consumed power.