Patent ID: 8598988

Claim:
A system for monitoring a plurality of RFID tags, the system comprising: a plurality of serially connected receivers along a receive path, a serially connected receiver configured to: relay a received receiver selection signal when a receiver selection signal identifies a selected receiver as being further along the receive path than the serially connected receiver; listen for an RFID response signal when the receiver selection signal identifies the serially connected receiver as being the selected receiver; and operate in a standby mode when the receiver selection signal identifies the selected receiver as being closer on the receive path than the serially connected receiver; a plurality of serially connected transmitters along a transmit path, a serially connected transmitter configured to: relay a received transmitter selection signal when a transmitter selection signal identifies a selected transmitter as being further along the transmit path than the serially connected transmitter; transmit an identification impulse when the transmitter selection signal identifies the serially connected transmitter as being the selected transmitter; and operate in a standby mode when the transmitter selection signal identifies the selected transmitter as being closer on the transmit path than the serially connected transmitter; and a reader responsive to a plurality of receive paths that include a plurality of serially connected receivers on a receive path, the reader being further responsive to a plurality of transmit paths that include a plurality of serially connected transmitters on a transmit path, the reader being configured to send the receiver selection signal along a selected receive path, the receiver selection signal identifying one of the plurality of serially connected receivers along the selected receive path as the selected receiver for listening for an RFID response signal, the reader being further configured to send the transmitter selection signal along a selected transmit path, the transmitter selection signal identifying one of the plurality of serially connected transmitters along the selected transmit path as the selected transmitter for transmitting the identification impulse; wherein the plurality of RFID tags include a plurality of first-protocol RFID tags and a plurality of second-protocol RFID tags, a first-protocol using passive RFID tags, a second-protocol using battery assisted RFID tags; wherein the transmitter selection signal further identifies a selected protocol according to which of the first-protocol and the second-protocol the identification impulse is to be transmitted; wherein the selected transmitter transmits the identification impulse in a low-power mode if the selected protocol is the second-protocol; and wherein the selected transmitter transmits the identification impulse in a high-power mode if the selected protocol is the first-protocol.