engleski

Holistic approach to energy saving in wireless networks of energy-hungry sensors for smart surveillance

Advancements in sensor and communication technology lead towards designing wireless distributed surveillance systems that outperform human abilities to sense the world that surrounds them. By devising monitoring systems that are immersed in the environment, unobtrusive and autonomous, human safety would be significantly enhanced. However, to ensure that highquality information is acquired and communicated to the user without latency, a wireless sensor network for surveillance application requires significant amounts of energy, which demands an often and expensive maintenance. This dissertation investigates energy-saving techniques in battery- powered wireless networks of energy-hungry sensors, such as video cameras and gas sensors for smart surveillance applications. The proposed power management is performed at three levels: sensor, node and network level. The research is performed on commercial off-theshelf wireless sensor nodes and on laboratory prototypes of wireless sensor nodes. The energysaving techniques are modeled and experimentally verified on systems for video surveillance and gas monitoring. The proposed context-aware multimodal and heterogeneous architecture of the sensor network limits the energy-hungry sensor’s active time and area, while wake-up radio ensures time- and energy-efficient communication between sensor nodes. By combining energy-savings in communication and sensing, we attain runtime prolongation of a wireless sensor node and network, without downgrading quality of service for the user (i.e., maintaining good recognition of interesting events). Moreover, the response latency in our approach is reduced for two orders of magnitude with respect to the state-of-the-art solutions. Based on the explored power management methods, we propose an architecture of a wireless monitoring system for indoor safety and comfort comprising video and gas sensors, useful for monitoring large open spaces such as airports and train stations. We show that a holistic approach to design complex surveillance system is necessary to ensure long-living autonomous smart devices.

Wireless sensor networks; energy-hungry sensors; power management; multimodal networks; holistic approach; wake-up radio; responsiveness; context-awareness; video surveillance; gas monitoring

nije evidentirano