Abstract: An electronic tag (10) is operable in both an RTF protocol mode and a TTF or TTO protocol mode. Typically, the tag is an RFID tag which includes an antenna (11) acting as a receiver for receiving a signal, and as a transmitter for transmitting a signal.

Abstract: A passive transponder (10) includes a resonator circuit (16) to receive a powering signal thereby to provide electrical energy to the transponder (10) by inductive coupling. The resonator circuit (16) is switchable between a high Q factor mode in which an induced voltage in the resonator circuit (16) decays slowly, and a low Q factor mode in which an induced voltage in the resonator circuit (16) decays more quickly. The transponder (10) includes a power storing arrangement (24) to store at least a portion of the electrical energy obtained from the powering signal.

Abstract: A radio frequency identification system comprises a reader associated, in use, with a transmitted beam of radio frequency energy and a plurality of transponders to be energized by the energy and each of which intermittently retransmits a response signal to be read by the reader. A method of monitoring the read quality of the reader comprises the steps of causing the transponders and beam to move relative to one another and defining a sequence of groups of transponders in the beam. For each transponder in a group, receiving the response signals transmitted and recording (68) a read count which is equal to the number of times the response signals was received and read by the reader while the transponder is in the beam. Thereafter computing (70) a statistical distribution of number of transponders against read count in the group. Data associated with the distribution is processed and compared (72) to stored historical data relating to a previously computed distribution for a previous group in the sequence.

Abstract: A radio frequency identification (RFID) system and more particularly a tag comprising a transponder forming parts of such a system. The tag preferably includes a substrate; a transponder mounted on the substrate; the transponder comprising electronic circuitry and an antenna connected to the circuitry; a sense element on the substrate which is sensitive to damage to the substrate and which is connected to a sense input of the circuitry; the antenna comprising a metal layer and the sense element a layer of conductive ink.