Patent ID: 8519823

Claim:
A method for locating a radio frequency identification (RFID) tag, comprising: identifying a desired RFID tag at a distance to be located among a plurality of RFID tags; transmitting a plurality of interrogation signals from a transmitter in a portable RFID reader at a selected transmit power level to determine a group of tags present within a region and a relative read rate of the desired RFID tag, the group including the desired RFID tag, wherein a physical location of the desired RFID tag is unknown, and wherein the read rate of the desired RFID tag comprises a rate of response to the plurality of interrogation signals; performing each of the following steps at least once to hone in on the physical location of the desired RFID tag using the transmitter: lowering the transmit power level based at least on a number of tags present in the determined group and the relative read rate, until the desired RFID tag's read rate is low; transmitting a subsequent interrogation signal from the transmitter at the adjusted transmit power level to determine a subsequent group of tags present within a subsequent region and a subsequent relative read rate of the desired RFID tag, and repositioning the transmitter.