RADIO-FREQUENCY IDENTIFICATION (RFID) TAG EMPLOYING UNIQUE RECEPTION WINDOW AND METHOD THEREFOR

摘要

AA radio-frequency identification (RFID) tag employing a unique reception window and method for operating the tag system provides low-power operation for enhanced tag battery life, while providing addressable tags that can receive commands and data from the system, which can be a wireless local area network (WLAN) incorporating location finding for locating the tags. Interference with other tags and other transmitters is prevented by either using a sniffer circuit to determine that no network transmission is in progress, or by using a special non-interfering coding sequence. A receiver within the tag is operated for a predetermined period of time after a periodic transmission is made from the tag, and an address decoder determines if the tag is being addressed. The receiver can receive data and/or commands after being addressed and is shutdown if the window time elapses, the tag is not addressed, or at the completion of data/command transfer.