Patent ID: 8350676

Claim:
A method of operating an RFID (Radio Frequency Identification) system including multiple RFID readers, comprising: grouping RFID readers spaced apart by more than a spacing distance to avoid collision between RFID readers into a single group to determine at least one group; classifying RFID readers included in each group into at least one sub-group based on a read time of each RFID reader; and driving the RFID readers such that RFID readers belonging to at least two different sub-groups that do not collide with each other simultaneously operate; wherein driving the RFID readers comprises: allowing RFID readers belonging to a first group to start to operate; detecting a first sub-group that finishes the operation thereof among sub-groups included in the first group; determining a second sub-group which belongs to a second group different from the first group and includes RFID readers that collide with RFID readers belonging to the first sub-group; and allowing the RFID readers belonging to the second sub-group to operate after the RFID readers belonging to the first sub-group finish the operations thereof.