Localization-based detection under network losses

We consider a networked system of sensors that measure the intensity of a source amidst background inside a two-dimensional monitoring area. The source intensity decays away from it, and the corresponding sensor measurements are random with a parameter determined by the intensity at sensor location. The detection problem is to infer the presence of a source based on measurements. Under a statistical independence condition, we show that a detection method based on maximum likelihood fuser performs below the individual sensors in presence of network losses. It has been previously shown that the localization of a source using measurements from multiple sensors leads to an improved detection, thereby establishing the effectiveness of a network over single or co-located sensors. We show that the communication losses degrade such network detection performance, particularly to levels below that of a single sensor under heavy losses. Under fairly general conditions on the source intensity decay functions and underlying measurement distributions, we quantify the loss of performance of the localization-based detection as a function of loss rate and packing number of state space. We present simulation and experimental results that illustrate the performance degradations due to network losses in detecting radiation sources.