Systems for Remotely Maintaining Inventory
A radio frequency identification device includes an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.
1 . (canceled)
2 . A system for remotely maintaining an inventory, comprising:
providing at each entry point to a predetermined area a radio frequency signal interrogator operable for transceiving spread spectrum radio frequency signals;
transporting one or more articles into the predetermined area, the articles each having an RFID tag associated with them, each of the RFID tags comprising a substrate with one or more antennas disposed thereon, a monolithic radio frequency transceiver integrated circuit coupled to the one or more antennas disposed adjacent the substrate and comprising a receiver for receiving spread spectrum radio frequency signals, a transmitter for communicating spread spectrum radio frequency signals, a controller, a memory for the persistent storage of identification data associated with the article, and a random number generator, and a battery coupled to supply power to the monolithic radio frequency transceiver integrated circuit;
transmitting from the radio frequency signal interrogator a command to the RFID tags to respond by transmitting data identifying the article stored within the memory within the RFID tag as articles pass in remote proximity to the interrogators to enter the predetermined area;
receiving in the radio frequency signal interrogator a spread spectrum radio frequency signal from the RFID tags including the data identifying the article; and
storing a count of the articles identified by the interrogator as entering the predetermined area.
3 . The system of claim 2 , wherein for each of the one or more RFID tags, the battery further comprises a thin film battery.
4 . The system of claim 3 , wherein for each of the one or more RFID tags, the monolithic radio frequency transceiver integrated circuit further comprises a wake circuit for causing the monolithic radio frequency transceiver integrated circuit to transition from a low power mode to a high power mode of operation in the presence of predetermined radio frequency signals.
5 . The system of claim 2 , wherein for each of the one or more RFID tags the monolithic radio frequency transceiver integrated circuit transmitter is operable to communicate spread spectrum radio frequency signals by reflection.
6 . The system of claim 2 , wherein for each of the one or more RFID tags the monolithic radio frequency transceiver integrated circuit transmitter is operable to communicate spread spectrum radio frequency signals by actively transmitting radio frequency signals.
7 . The system of claim 2 , wherein for each of the one or more RFID tags the monolithic radio frequency transceiver integrated circuit receiver is operable to receive spread spectrum modulated signals modulated using one selected from the group of amplitude shift keying, phase shift keying, and the combination thereof.
8 . The system of claim 2 , wherein for each of the one or more RFID tags the monolithic radio frequency transceiver integrated circuit is operable to generate a random number responsive to a radio frequency command received as a portion of a radio frequency signal by the radio frequency receiver.
9 . The system of claim 2 , wherein for each of the one or more RFID tags the monolithic radio frequency transceiver integrated circuit random number generator further comprises a linear feedback shift register.
10 . The system of claim 2 , wherein for each of the one or more RFID tags the monolithic radio frequency transceiver integrated circuit further comprises an analog-to-digital converter.
11 . The system of claim 10 wherein for each of the one or more RFID tags, the RFID tag further comprises a sensor for sensing a physical characteristic coupled to the analog-to-digital converter.
12 . The system of claim 11 wherein for each of the one or more RFID tags the sensor is formed within the monolithic radio frequency transceiver integrated circuit.
13 . The system of claim 11 wherein for each of the one or more RFID tags the sensor is one selected from the group of a voltage sensor, a temperature sensor, a magnetic field sensor, and combinations thereof.
14 . The system of claim 2 , wherein for each of the one or more RFID tags the monolithic radio frequency transceiver integrated circuit is operable to communicate a random number generated by the random number generator using spread spectrum radio frequency signals communicated by the radio frequency transmitter.
15 . The system of claim 2 , wherein for each of the one or more RFID tags, the memory of the monolithic radio frequency transceiver integrated circuit further comprises a non-volatile memory.
16 . The system of claim 2 wherein for each of the one or more RFID tags, the memory of the monolithic radio frequency transceiver integrated circuit further comprises a readable and writeable memory.
17 . The system of claim 2 , wherein for each of the one or more RFID tags the memory of the monolithic radio frequency transceiver integrated circuit further comprises unalterable indicia uniquely assigned to the monolithic radio frequency transceiver integrated circuit.
18 . The system of claim 2 , wherein for each of the one or more RFID tags the control logic of the monolithic radio frequency transceiver integrated circuit further comprises one selected from the group of a microprocessor, a microcontroller, and combinations thereof.