ONUs placement for reduced sensors' energy consumption in PON-WSN hybrid networks

Considering resources of sensor nodes are constrained in wireless sensor networks (WSNs) and optical networks can provide long distance and high-bandwidth communications, the design of a hybrid access network that integrates wireless sensor networks with passive optical networks (PONs) is a promising way to reduce sensors' energy consumption. In PON-WSN hybrid networks, ONUs perform as cluster heads with high processing capacity and power in WSNs. Since sensor nodes' number is mostly on a large scale and their locations are irregular, it's necessary to select optimal ONUs' locations so that a sensor can send packets to an ONU with least energy consumption. In this paper, we employ a hybrid approach combining Genetic Algorithm and Tabu Search to optimize ONUs deployment problem. Simulation results confirm that compared to cluster heads changing in rounds in WSNs and random ONUs placement in PON-WSN hybrid networks, our approach performs better in reducing sensors' energy consumption.