Patent ID: 7336182

Claim:
A method for determining if a tag has been removed from an asset within an indoor facility, the method comprising: tracking a location of an asset bearing a tag, the tag comprising a processor, a motion sensor, a transceiver, a tag removal sensor, a power source having a limited supply of electrical power; detecting motion of the tag by the motion sensor and communicating the motion to the processor; transmitting an activation signal from the processor to the tag removal sensor, the activation signal activating the tag removal sensor from a low power consumption state to an activation state, wherein the tag removal sensor is an optical sensor that emits light from the tag to the asset and receives the light reflected from a surface of the asset indicating that the tag is attached to the asset: determining if the tag is currently attached to the asset; transmitting an unattached signal from the tag removal sensor to the processor and from the processor to the transceiver to indicate that the tag is currently unattached to the asset; broadcasting the unattached signal from the transceiver of the tag to a plurality of network sensors positioned within an indoor facility; and transmitting the unattached signal from at least one of the plurality of network sensors to a positioning engine to generate a warning.