Reliability optimization for industrial WSNs with FD relays and multiple parallel connections

This article investigates the ultra-reliable communication for industrial wireless sensor networks (IWSNs), where frequency diversity, path diversity and cooperative diversity are jointly investigated. We propose a novel IWSN equipped with the full-duplex (FD) relays and carrier aggregation (CA) technique, to improve the reliability of all sensors. We derive a closed-form expression for the reliability characterization based on signal-to-interference-plus-noise (SINR) model for sensors connecting to sink node either via FD relays or direct communications. We formulate a joint resource allocation problem for reliability maximization, considering sub-carrier assignment, relay selection and power control. We propose to apply the distributed decision making (DDM) framework to decouple the problem into two sub-problems and find the joint optimal solution in an iterative manner. We further propose an improved artificial bee colony algorithm to obtain the optimal results for each sub-problem. Our simulation results showcase the reliability increases with increasing the number of FD-relays and sub-carriers. We also show that the FD and CA techniques along with our proposed algorithm can be an effective way for improving the reliability of IWSNs.