A 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.