Patent ID: 7009495
Filing Date: 2006-03-07
Classification: G06K

Abstract:
1. An RFID system comprising: an RFID reader configured to issue a first RF command requesting that RF tags identify themselves, a subsequent second RF command, and timing information defining a plurality of timeslots; and a plurality of RF tags in selective communication with the reader, the RF tags having respective IDs, respective tags being configured to randomly select a timeslot in which to reply to the first RF command, and to issue a first RF reply in response to the first RF command in the randomly selected timeslot, the first RF reply incompletely identifying the tag to the reader, the respective tags being further configured to issue a second RF reply in response to the second RF command to more completely identify the tag to the reader; wherein the reader is configured to store data representing the timeslot in which an RF reply was received by the reader and wherein the second RF command indicates the timeslot for which a reply was received from a tag.