Patent ID: 8310342
Filing Date: 2012-11-13
Classification: G06K

Abstract:
1. An anti-collision method of a radio frequency identification (RFID) system comprising a reader, and a plurality of tags each having a corresponding identification (ID), the anti-collision method comprising: transmitting an ID request value from the reader to the plurality of tags, the ID request value containing at least one code forming identifications (IDs) of the plurality of tags; receiving the IDs from the plurality of tags which contains the ID request value, each entire ID of the IDs being transmitted from a corresponding tag of the plurality of tags in response to the single ID request value transmitted from the reader, wherein the ID request value is transmitted to the plurality of tags before the IDs are received from the plurality of tags; if at least two of the received IDs collide, generating a collision bit position (CBP) value indicating bit position of collision of the collided IDs by using the collided IDs, and transmitting the ID request value and the generated collision bit position (CBP) value to each of tags of the plurality of tags that have transmitted the collided IDs; receiving values representing collision bits of the collided IDs from the tags that have transmitted the collided IDs in response to the transmitted ID request value and collision bit position (CBP) value; and identifying IDs of the tags that have transmitted the collided IDs based on the values representing the collision bits of the collided IDs received from the tags that have transmitted the collided IDs.