Measuring the Quality of Surveillance in a Wireless Sensor Network

Quality of Surveillance (QoSv) is a generic measure of the coverage offered by a given network of sensors over the field it monitors. In this work, we consider it to be the length of the longest straight line segment that does not pass through the sensing zone of any sensor. It can be seen as the longest length that an intruder may travel along a straight line, before being detected. An easy to implement algorithm for computing the QoSv in a rectangular field containing a set of n identical sensors is proposed. The time and space complexities of our algorithm are O(n2log n) and O(n) respectively. It is also shown that a minor modification of the algorithm runs in O(n2) time and space.