Ensuring survivability of resource intensive sensor networks through ultra-low power overlays

Nodes in Wireless Sensor Networks (WSN) typically have limited power supply, while networks are often expected to be functional for extended periods. Therefore, the minimization of energy consumption and the maximization of network lifetime are key objectives in WSN. This paper proposes an overlay, energy optimised, sensor network to extend the functional lifetime of an energy intensive sensor network application. The overlay network consists of additional nodes that exploit recent advances in energy harvesting and wake up radio technologies, coupled with an application specific, complementary, ultra-low power sensor. Experimental results and simulations demonstrate that this approach can ensure survivability of energy-inefficient sensor networks. Simulating applications using energy-intensive videocameras and air quality sensors, combined with the proposed overlayed, ultra-low power sensor network, demonstrates that this approach can increase functional lifetime toward perpetual operation, and is suitable for WSN applications in which complementarity exists between the required energy-intensive sensors and low cost sensors that can be used as triggers.