Carrier with antenna for radio frequency identification

• US 6,340,932 B1
• Filed: 06/27/2000
• Issued: 01/22/2002
• Est. Priority Date: 06/02/1998
• Status: Expired due to Term

• Current Assignee: RF Code Incorporated
• Original Assignee: RF Code Incorporated
• Inventors: Rodgers, James L., Coulthard, John J., Lastinger, Roc A., Fowler, Billy C., Rehman, Mohammad A., Jaecks, Howard K., Picard, Paul A.
• Primary Examiner(s): Lee, Benjamin C.
• Application Number:
  US09/604,180
• Time in Patent Office: 574 Days
• Field of Search: 340/572.7, 340/10.1, 340/572.8, 340/539, 340/10.4, 340/572.1, 343/719, 343/872, 343/700, 342/42
• US Class Current: 340/572.7
• CPC Class Codes: G01S 13/753 using frequency selective elements, e.g. resonator
• CPC Class Codes: G01S 13/756 using a signal generator for modifying the reflectivity of the reflector G01S13/758 takes precedence
• CPC Class Codes: G01S 13/758 using a signal generator powered by the interrogation signal
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 19/0724 the arrangement being a circuit for communicating at a plurality of frequencies, e.g. for managing time multiplexed communication over at least two antennas of different types
• CPC Class Codes: G06K 19/07779 the inductive antenna being a coil
• CPC Class Codes: G06K 19/07783 the coil being planar
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10039 interrogator driven, i.e. synchronous
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles
• CPC Class Codes: G08B 13/2417 having a radio frequency identification chip
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 23/00 Antennas with active circuits or circuit elements integrated within them or attached to them
• CPC Class Codes: H01Q 5/35 using two or more simultaneously fed points
• CPC Class Codes: H01Q 5/40 Imbricated or interleaved structures; Combined or electromagnetically coupled arrangements, e.g. comprising two or more non-connected fed radiating elements
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 9/14 : Length of element or elements adjustable telescopic elements H01Q1/10

Abstract

A carrier, as used for example to transport several radio frequency identification devices, includes a circuit having an antenna and a series capacitor for tuning the antenna. Enhanced transceiver communication results when transceivers are placed in the carrier. Alternately, a carrier may include first and second antenna circuits, each having a capacitor for tuning the respective antenna. The two circuits may cooperate so that energy received in a first pattern is re-radiated in a second pattern for further enhanced transceiver communication, such as detection of the presence of the RFID device within the carrier.

Claims

1. A structure for retaining a provided plurality of radio frequency identification devices in a common location, the structure comprising:

a. a support that maintains the plurality at the common location; and

b. a circuit electrically isolated from the plurality, the circuit comprising a first antenna that re-radiates radio frequency energy for improving an operation of at least one of the radio frequency identification devices.

2. The structure of claim 1 wherein the support is part of a container that contains the plurality of radio frequency identification devices.

3. The structure of claim 2 wherein the container supports the plurality of radio frequency identification devices for transporting the plurality as a group within range for communication.

4. The structure as in any one of claims 1-3 wherein the circuit further comprises a capacitance that tunes the antenna.

5. The structure of claim 1 wherein the circuit has a resonant frequency.

6. The structure of claim 5 wherein:

a. the radio frequency identification devices operate with respect to a frequency band; and

b. the resonant frequency is not within the band.

7. The structure as in any one of claims 1-3 and 5-6 wherein the circuit further comprises a second antenna coupled to the first antenna for providing a combined antenna pattern.

8. The structure of claim 1 wherein:

a. a radio frequency identification device of the plurality has a second antenna; and

b. the first antenna cooperates with the second antenna to extend the communication range of the radio frequency identification device.

9. The structure of claim 1 wherein the first antenna comprises a loop conductor.

10. The structure as in any one of claims 1-3, 5-6 and 8-9 wherein:

a. the structure comprises a plurality of planar surfaces; and

b. the circuit comprises an antenna portion mechanically coupled to each of the planar surfaces.