1. A wireless sensor network system for detecting the location of a node, the wireless sensor network comprising: a plurality of anchor sensors each comprising: a signal receiver configured to detect a received signal, the received signal comprising noise and further comprising a transmitted signal from the node when the node is transmitting the transmitted signal, the node being located at an exact location that is unknown to each of the plurality of anchor sensors, the exact location being in a region that is known to each of the plurality of anchor sensors, and the transmitted signal being wirelessly transmitted from the node when the node is transmitting the transmitted signal; a processing module; and a transmitter; and a fusion center, wherein: the processing module of each anchor sensor of the plurality of anchor sensors performs: determining a probability of whether the node is present at each of a plurality of grid points of the region; and determining a local detection determination of whether the node is detected by the anchor sensor based at least in part on the probabilities of whether the node is present at the plurality of grid points; and the transmitter of each anchor sensor of the plurality of anchor sensors sends the local detection determination from the anchor sensor to the fusion center.