RFID REPEATER FOR RANGE EXTENSION IN MODULATED BACKSCATTER SYSTEMS

• US 20100156610A1
• Filed: 08/27/2009
• Published: 06/24/2010
• Est. Priority Date: 09/03/2008
• Status: Active Grant

• Current Assignee: CHECKPOINT SYSTEMS, INC. (CCL Industries Incorporated)
• Original Assignee: CHECKPOINT SYSTEMS, INC. (CCL Industries Incorporated)
• Inventors: Ramchandran, Kannan, Wild, Ben J., Madhow, Upamanyu
• Granted Patent: US 8,988,197 B2
• Time in Patent Office: Days
• US Class Current: 340/10.340
• 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

Abstract

A backscatter tag system including a tag having tag circuitry and a reader for transmitting a command signal to the tag includes an energizer node for transmitting an energy signal to the tag to energize the tag and provide energy for operating the tag circuitry and for emitting a backscatter signal by the tag. The energizer node includes an energizer receiver for receiving the command signal from the reader to provide a received command signal and an energizer transmitter for transmitting the received command signal from the reader to the tag. The energizer node transmits both the energy signal and the received command signal to the tag. The energizer transmitter can transmit a sinusoidal signal, a frequency hopping signal, a spread spectrum signal, or a frequency shifted signal to the tag. The backscatter tag circuitry can include a processor.

Claims

1. A backscatter tag system including at least one tag having tag circuitry and a reader for transmitting a command signal to the at least one tag, comprising:

an energizer node for transmitting an energy signal to the at least one tag to energize the at least one tag and provide energy for operating the tag circuitry and for emitting a backscatter signal by the at least one tag;

the energizer node comprising;

an energizer receiver for receiving the command signal from the reader in order to provide a received command signal;

an energizer transmitter in order to transmit the received command signal from the reader to the at least one tag; and

whereby the energizer node transmits both the energy signal and the received command signal to the at least one tag.

2. The backscatter tag system of claim 1, wherein the energizer transmitter transmits a sinusoidal signal to the at least one tag.

3. The backscatter tag system of claim 1, wherein the energizer transmitter transmits a frequency hopping signal to the at least one tag.

4. The backscatter tag system of claim 1, wherein the energizer transmitter transmits a spread spectrum signal to the at least one tag.

5. The backscatter tag system of claim 1, wherein the energizer transmitter transmits a frequency shifted signal to the at least one tag.

6. The backscatter tag system of claim 1, wherein the tag circuitry comprises a processor.

7. The backscatter tag system of claim 1, wherein the at lease one tag operates in an open loop mode emitting a backscatter signal independently of the command signal from the reader.

8. The backscatter tag system of claim 1, wherein the at lease one tag operates in a closed loop mode emitting a backscatter signal in accordance with the command from the reader.

9. The backscatter tag system of claim 8, wherein the at lease one tag responds to the reader in accordance with a predetermined reader protocol.

10. The backscatter tag system of claim 1, wherein the energizer receiver and the energizer transmitter operate in differing frequency bands.

11. The backscatter tag system of claim 1, wherein the energizer node comprises a battery.

12. The backscatter tag system of claim 1, including a plurality of backscatter signals further comprising deterministic intervals between the backscatter signals of the plurality of backscatter signals.

13. The backscatter tag system of claim 1, including a plurality of backscatter signals further comprising random intervals between the backscatter signals of the plurality of backscatter signals.

14. The backscatter tag system of claim 1, wherein the at least one tag is a multimode tag and the multimode tag changes from one mode to another mode in accordance with the command signal from the reader.

15. The backscatter tag system of claim 14, wherein the command signal from the reader for the multimode tag to change from one mode to another is transmitted from the reader to the multimode tag by way of the energizer node.

16. The backscatter tag system of claim 14, wherein the command signal from the reader comprises a command for the multimode tag to change its frequency of operation.

17. The backscatter tag system of claim 1, wherein the at least one node includes an on mode and an off mode and the command signal from the reader comprises a command for the multimode tag to turn off

18. The backscatter tag system of claim 1, further comprising a plurality of tags and a plurality of energizer nodes operating at respective energizer node frequencies wherein the reader synchronizes the frequencies of the respective energizer node frequencies in order to control interference of tags of the plurality of tags.

19. The backscatter tag system of claim 1, further comprising a plurality of tags and a plurality of energizer nodes having respective energizer node timing wherein the reader synchronizes the timing of the energizer nodes of the plurality of energizer nodes in order to control interference of tags of the plurality of tags.