Wireless sensor networks: application driver for low power distributed systems

Summary form only given. Wireless sensor networks allow deployment of sensing elements close to the phenomena of interest. Sensing close to the signal generation point should lead to improved SNR in general, and enable detection in otherwise obstructed environments. This fundamental benefit of local sensing, combined with the decreasing cost and increasing availability of low cost microsensors/actuators and processors, suggests that effective systems will exploit densely distributed elements. However, dense sensing capability is only scalable if the elements are networked to support collaborative processing near the sensory inputs. Therefore, in many contexts low-power wireless communication is a critical enabler of these systems because it overcomes the logistical infeasibility of deploying wires in remote, dynamic, and mobile-node, contexts. The spatially dense and temporally continuous monitoring capabilities of wireless sensor networks will transform the way in which we understand and interact with the physical world: e.g., contaminant flow monitoring in soil, air, and water; precision agriculture; transportation and traffic management; and remote-habitat monitoring for biocomplexity studies. However, in order for wireless sensor networks to effectively provide dense and continuous monitoring/data collection, they must be able to operate unattended for long periods of time. Long lifetime obviously requires that the individual components be low-power. However, component-level efficiency is not sufficient; the distributed sensor network as a whole must be designed with energy-efficiency as a primary constraint. This paper will elaborate on these issues and will also argue for focused collaboration between the low-power design communities and the systems community to enable larger scale experimental efforts.