Section: Application Domains

Interacting with the real world

Sensor networks have been investigated and deployed for decades already; their wireless exten- sion, however, has witnessed a tremendous upsurge in recent years. This is mainly attributed to the unprecedented operating conditions of wireless sensor networks (WSNs), i.e. a potentially enormous amount of sensor nodes, reliably operating under stringent energy constraints. WSNs allow for an unbounded sensing of the environment. It is anticipated that within a few years, sensors will be deployed in a variety of scenarios, ranging from environmental monitoring to health care, from the public to the private sector, etc. They will be battery-driven and deployed in great numbers in an ad hoc fashion, requiring communication protocols and embedded system components to run in an utmost energy efficient manner. Prior to large-scale deployment, how- ever, a gamut of problems has to be solved which relates to various issues, such as the extraction of application scenarios, design of suitable software and hardware architectures, development of communication and organization protocols, validation and first steps of prototyping, etc. Our objective will be to explore new event-driven and asynchronous software and hardware architectures, tailored to extremely low power consumptions; to propose new communication and organization protocols, which are optimized in terms of energy consumption and robustness; to find new application protocols that are designed for data fusion and aggregation; to study new network structures which facilitate auto-configuration and auto-organization; to provide tools for modeling and validation, which also take into account the physical environment and the interaction with the wireless sensor nodes. A specific application field concerns on-body applications. Wireless Body Area Networks (BAN) are now a well known acronym which encompasses scenarios in which several sensors and actuators are located on or inside the human body to sense different data, e.g. physiological information at different places on the body, and transfer them wirelessly towards a remote co- ordination unit which processes, forwards, takes decisions, alerts, records, etc. The use of BAN spans a wide area, from medical and health care to sport through leisure applications, which definitely makes the definition of a standard air interface and protocol highly challenging. Since it is expected that such devices and networks would have a growing place in the society and become more stringent in terms of quality of service, coexistence issues will be critical. Indeed, the radio resource is known to be scarce. The recent regulation difficulties of UWB systems as well as the growing interest for opportunistic radios show that any new system have to make an efficient use of the spectrum. This also applies to short range personal and body area network systems which are subject to huge market penetrations.