Energy Efficient Multi-Object Tracking in Sensor Networks

The problem of tracking multiple objects moving through a network of wireless sensors is studied. It is assumed that each sensor has a limited range for detecting the presence of the object, and that the network is sufficiently dense so that the sensors cover the area of interest. In order to conserve energy the sensors may be put into a sleep mode with a timer that determines the sleep duration. It is assumed that a sensor that is asleep cannot be communicated with or woken up, and hence the sleep duration needs to be determined at the time the sensor goes to sleep based on all the information available to the sensor. The objective is to track the location of the objects to within the accuracy of the range of the sensor. Having sleeping sensors in the network could result in tracking errors, and therefore there is a tradeoff between the energy savings and the tracking errors that result from the sleeping actions at the sensors. Sleeping policies that optimize this tradeoff are designed, and their performance analyzed. This work is an extension of previous work that considered the tracking of only a single object.