A Fault-tolerant Approach to Sensor Deployment in Distributed Sensor Networks

Distributed sensor networks (DSNs) are a key part of the surveillance and reconnaissance infrastructure in any modern military system. DSNs offer several important benefits, such as ease of deployment, responsiveness to battlefield situations, survivability, agility and easy sustainability. These benefits make DSNs a lethal weapon for the US army, providing it with high quality of surveillance, and reconnaissance data necessary for any combat operation. The effectiveness or quality of service (QOS) provided by any DSN depends on the coverage provided by the sensor deployment strategy. In this paper, we present novel fault-tolerant strategies for sensor deployment that provide sufficient coverage under the constraint that up to K (K ≥ 0) sensors can fail. Sensor placement is essential for effective utilization of sensor network resources. Intelligent sensor placement facilitates the unified design and operation of sensor/exploitation systems, and decreases the need for excessive network communication for surveillance, target location and tracking. In a typical scenario, surveillance authorities have several different types of sensors available, which can be appropriately placed in the sensor field. These sensors differ from each other in their modalities, monitoring range, detection capabilities, and cost. Intelligent sensor deployment strategies are necessary to minimize cost and yet provide sufficient sensor coverage. A sensor deployment strategy should also be inherently fault-tolerant to make it effective. It is clearly not feasible to continuously monitor sensor status and identify failing sensors over an extended period of time. Sensors often operate in hostile conditions under severe resource constraints, and it is desirable to limit communication to useful target detection, localization, and tracking data. Therefore, the initial sensor deployment strategy must ensure that the quality of service, i.e. coverage, does not degrade due to the failure of sensors