A method and apparatus for monitoring untagged objects in a target area including calibrating a radio environment monitoring system including a rules engine and a baseline data set for a target area by recording a set of changes to the RF environment fingerprint of the target area received by the radio environment monitoring system as the target area is filled with objects. During system operation, scanning the target area with the radio environment monitoring system for a current RF environment fingerprint, comparing the current RF environment fingerprint with the baseline data set by a rules engine and reporting an output of the rules engine.