Cascade Mobile Sensor Movement for Coverage Hole Healing
Cascade movement of mobile sensors are useful when the leaving of mobile sensors may create new coverage holes if the network does not have sufficient redundant mobile sensor or the coverage holes are located beyond the maximum moving distance of their nearest mobile sensors in a hybrid wireless sensor network. We first analyze the sensor network where cascade movement of mobile sensors may appear and introduce vacancies to transform the network. Then we propose a distributed algorithm that permits cascade movement of mobile sensors and outputs at least 1/5 of the optimal maximum total residual energy of all scheduled mobile sensors for the movement. Simulation result shows that when the coefficient of mobile sensor’s maximum moving distance is low mobile sensors significantly retaining more total remaining energy by cascade movement. And the algorithm permits cascade movement always provides higher coverage hole healing ratio than the algorithm does not.
Keywords: cascade, mobile sensor, coverage hole, hybrid network, sensor network, scheduling