Abstract: Method includes receiving plurality of measured signal strengths, computing estimated intruder signal strength associated with each of plurality of potential intruder locations, and selecting estimated intruder location. Receiving plurality of measured signal strengths includes receiving plurality of measured signal strengths each associated with sensor included in plurality of sensors distributed in monitored area that includes plurality of potential intruder locations. Selecting estimated intruder location includes selecting as estimated intruder location, first potential intruder location associated with estimated intruder signal strength greater than or equal to estimated intruder signal strength associated with another potential intruder location adjacent to first potential intruder location. Computer-readable medium containing code that executes method.