Energy-saving and robust wireless sensor networks with self-organization
Recently, due to advances in wireless and micro-electromechanical technologies, extremely small sensor nodes featuring wireless communication facilities have been developed, and as a result wireless sensor networks have received considerable attention. Sensor networks are particularly useful for a wide range of applications as they possess sensing capabilities without the need for implementing a centralized infrastructure. However, some critical technical problems still need to be resolved in wireless sensor networks, one of which is the energy efficiency of sensor nodes with limited battery life. In order to save energy, we focus on intermittent receiver-driven data transmission (IRDT) protocol. We propose a self-organized method for a sensor node to determine a proper intermittent interval, which reduce power consumption.
Robustness is one of the significant concerns in sensor networks where sensor nodes and wireless links are subjected to frequent failures. In wireless sensor networks, in particular sensor nodes suffer from failures under hostile environmental conditions and energy depletions. Robustness means a property to maintain or recover performance in the face of uncertain environmental variations. Without robustness against environmental variations, once network conditions severely perturbs, system performance falls into critical regions. We separate robustness into `robustness’ and `resilience,’ as properties to `maintain’ and `recover’ performance in the face of uncertain environmental variations, respectively, and define them in a quantitatively evaluable format. Finally, we show the guideline for improve network robustness and resilience.