Patent ID: 7737856

Claim:
A system for monitoring a plurality of transceivers located in an area to be monitored, the system comprising: means for enabling one transceiver of the plurality of transceivers and disabling all other transceivers of the plurality of transceivers; a transmit coil for emitting a high frequency electromagnetic field, the one transceiver transmitting a signal in response to the field of the transmit coil; at least one reader having a plurality of reader coils for receiving the signal transmitted by the one transceiver, the plurality of reader coils being suitably arranged in the vicinity of the area to be monitored; and an evaluator for determining a position of the one transceiver from the signal received from the one transceiver by the plurality of reader coils, wherein the evaluator is configured to determine the position of the one transceiver from the signal received from the one transceiver by comparing the levels of the signal received by the plurality of reader coils from the one transceiver.