Adaptive Duty-Cycled MAC for Low-Latency Mission-Critical Surveillance Applications

Mission-critical surveillance applications such as intrusion detection or disaster response have strong requirements in communication delays. We consider a Wireless Image Sensor Network (WISN) with a scheduling of image sensor node’s activity based on the application criticality level. Sentry nodes capable of detecting intrusions with a higher probability than others will alert neighbor nodes as well as activating cover sets member for image disambiguation or situation-awareness purposes. At the access level, we consider duty-cycled Medium Access Control to periodically set nodes in sleep mode for energy preservation. However, in doing so, care must be taken to also preserve the quality of event detection and sentry nodes must still be able to propagate quickly alert messages. We propose an original approach to dynamically determine the duty-cycle values of image sensor nodes to increase the probability of matching active period between nodes, thus reducing the alert latency while globally reduce the energy consumption.