Industrial wireless sensor networks (IWSNs) employ Trajectory Based Forwarding (TBF) [5], a popular source routing technique, where source precomputes the optimal trajectory, comprising active nodes only, and inserts it in packet header. TBF ensures optimum hop distance to decrease overall energy consumption. To reduce the consumption further, we propose for energy-critical IWSNs the use of multiple cooperative relays within every single hop of TBF. However, this is possible only if the node density exceeds a minimum level, which we determine in this paper. Mathematical analyses prove that in-hop relaying is better than direct forwarding in terms of energy saving, latency and reliability.
['Debdeep Saha', 'Somprakash Bandyopadhyay']
Finding minimum node density for energy-efficient in-hop cooperative relaying in industrial WSNs