Remote communication device and system for communication

• US 20040246100A1
• Filed: 06/04/2004
• Published: 12/09/2004
• Est. Priority Date: 06/06/2003
• Status: Active Grant

• Current Assignee: Stemco Products, Inc. (Enpro Industries Incorporated)
• Original Assignee: Stemco LP (Enpro Industries Incorporated)
• Inventors: Kranz, Mark J.
• Granted Patent: US 7,710,239 B2
• Time in Patent Office: Days
• US Class Current: 340/10.1
• CPC Class Codes: G06K 19/0717 the sensor being capable of sensing environmental conditions such as temperature history or pressure
• 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 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 7/10069 the collision being resolved in the frequency domain, e.g. by hopping from one frequency to the other frequency hopping or spread spectrum techniques H04B7/00

Abstract

The present invention provides a remote communication device (i.e., radio frequency identification (RFID) tag) and system for communicating between one or more RFID tags and a reader using a frequency modulation method to encode binary data.

Claims

1. A remote communication device comprising:

an antenna operable to receive and backscatter a carrier signal, wherein the backscattered carrier signal further comprises a secondary signal within an identification bandwidth; and

a signal processing circuit coupled to the antenna, the signal processing circuit comprising at least one encoding circuit operable to encode binary data into the backscattered carrier signal by periodically modulating the frequency of the secondary signal from one encoding frequency to another one of 2ⁿ+1 encoding frequencies within the identification bandwidth,

wherein

n is an integer greater than or equal to 1.

2. The remote communication device of claim 1, wherein n represents the number of bits of data encoded by a change from one encoding frequency to another encoding frequency.

3. The remote communication device of claim 1, wherein the carrier signal and the secondary signal comprise radio frequency signals.

4. The remote communication device of claim 1, wherein n is an integer from 1 to 5.

5. The remote communication device of claim 1, wherein the antenna and the signal processing circuit are configured to generate a supply voltage from the carrier signal.

6. The remote communication device of claim 1, wherein the signal processing circuit is further operable to activate and deactivate upon receipt of remote activation and deactivation signals, respectively.

7. The remote communication device of claim 1, further comprising a sensor coupled to the signal processing circuit, wherein the signal processing circuit is further operable to receive a sensor signal from the sensor, encode the sensor signal, and include the encoded sensor signal in the secondary signal.

8. A reader comprising:

an antenna operable to receive a plurality of backscattered signals from a plurality of remote communication devices,

wherein

each backscattered signal comprises a carrier signal and a secondary signal, wherein the secondary signal comprises a series of up to 2ⁿ+1 encoding frequencies within an identification bandwidth; and

a receiving circuit coupled to the antenna operable to extract data from each of the backscattered signals by converting a change from one encoding frequency to another encoding frequency in the secondary signal of each backscattered signal into n bits of binary data,

wherein

n is an integer greater than or equal to 1.

9. The reader of claim 8, wherein the backscattered signal comprises radio frequency signals.

10. The reader of claim 8, wherein the receiving circuit is operable to extract data simultaneously from each of the backscattered signals.

11. The reader of claim 8, wherein the receiving circuit comprises at least one processing circuit operable to extract data from each of the backscattered signals, wherein each at least one processing circuit is operable to process a secondary signal within a predetermined identification bandwidth.

12. The reader of claim 8, wherein n is an integer from 1 to 5.

13. The reader of claim 8, further comprising a transmitting circuit coupled to the antenna, wherein the transmitting circuit is operable to transmit a carrier signal to the plurality of remote communication devices.

14. The reader of claim 13, wherein the antenna comprises a transmitting antenna coupled to the transmitting circuit and a receiving antenna coupled to the receiving circuit.

15. The reader of claim 13, wherein the transmitting circuit is operable to transmit a carrier signal that regularly hops to a different frequency.

16. A communication system comprising:

a plurality of remote communication devices,

wherein

each remote communication device comprises;

a remote communication device antenna operable to receive and backscatter a carrier signal, wherein the backscattered carrier signal further comprises a secondary signal within an identification bandwidth; and

a signal processing circuit coupled to the remote communication device antenna, the signal processing circuit comprising at least one encoding circuit operable to encode binary data into the backscattered carrier signal by periodically modulating the frequency of the secondary signal from one to another one of 2ⁿ+1 encoding frequencies within the identification bandwidth, and

a reader comprising;

a reader antenna operable to receive the plurality of backscattered carrier signals from the plurality of remote communication devices, and

a receiving circuit coupled to the reader antenna operable to extract data from each of the backscattered carrier signals by converting change from one encoding frequency to another encoding frequency in the secondary signal of each backscattered carrier signal into n bits of binary data,

wherein

n is an integer greater than or equal to 1.

17. The communication system of claim 16, wherein the receiving circuit of the reader is operable to extract data simultaneously from each of the backscattered signals.

18. The communication system of claim 16, wherein the receiving circuit of the reader comprises at least one processing circuit operable to extract data from each of the backscattered signals, wherein each at least one processing circuit is operable to process a secondary signal within a predetermined identification bandwidth.

19. The communication system of claim 16, wherein the reader further comprises a transmitting circuit coupled to the reader antenna, wherein the transmitting circuit and the reader antenna are operable to transmit a carrier signal to the plurality of remote communication devices.

20. The communication system of claim 19, wherein the reader antenna comprises a transmitting antenna coupled to the transmitting circuit and a receiving antenna coupled to the receiving circuit.

21. The communication system of claim 19, wherein the transmitting circuit and the reader antenna are operable to transmit a carrier signal that regularly hops to a different frequency.

22. The communication system of claim 16, wherein the carrier signal and the backscattered carrier signal comprise radio frequency signals.

23. The communication system of claim 16, wherein the remote communication device antenna and the signal processing circuit are configured to generate a supply voltage from the carrier signal.

24. The communication system of claim 16, wherein the signal processing circuit of the remote communication devices is further operable to activate and deactivate upon receipt of remote activation and deactivation signals, respectively.

25. The communication system of claim 16, wherein the remote communication devices further comprise a sensor coupled to the signal processing circuit, wherein the signal processing circuit is further operable to receive a sensor signal from the sensor, encode the sensor signal, and include the encoded sensor signal in the secondary signal.

26. The communication system of claim 16, wherein n is an integer from 1 to 5.

27. A method for communication between a remote communication device and a reader comprising:

transmitting a carrier signal;

receiving the carrier signal at a remote communication device;

backscattering the carrier signal wherein the backscattered carrier signal further comprises a secondary signal within an identification bandwidth;

encoding binary data into the backscattered signal by periodically modulating the secondary signal from one to another one of 2ⁿ+1 encoding frequencies within the identification bandwidth,

wherein

n is an integer greater than or equal to 1;

receiving the backscattered carrier signal from the remote communication device at a reader; and

extracting data from the backscattered carrier signal.

28. The method of claim 27, wherein the step of extracting data from the backscattered carrier signal comprises removing the carrier signal and converting each change from one encoding frequency to another encoding frequency hop in the secondary signal into n bits of data.

29. The method of claim 27, wherein the binary data encoded into the backscattered carrier signal is provided by a sensor.

30. The method of claim 27, wherein the step of transmitting a carrier signal comprises regularly hopping the carrier signal to a different frequency.

31. The method of claim 27, wherein n is an integer from 1 to 5.

32. A method for communication between a plurality of remote communication devices and a reader comprising:

transmitting a carrier signal;

receiving the carrier signal at a plurality of remote communication devices;

backscattering the carrier signal at each remote communication device, wherein the backscattered carrier signal further comprises a secondary signal within an identification bandwidth;

encoding binary data into the backscattered signal by periodically modulating the secondary signal from one to another one of 2ⁿ+1 encoding frequencies within the identification bandwidth,

wherein

n is an integer greater than or equal to 1;

receiving the backscattered signals from each remote communication device; and

extracting data from each remote signal.

33. The method of claim 32, wherein the step of extracting data from each backscattered carrier signal comprises removing the carrier signal and converting each change from one encoding frequency to another encoding frequency in the secondary signal into n bits of data.

34. The method of claim 32, wherein the binary data encoded into each backscattered carrier signal is provided by a sensor.

35. The method of claim 32, wherein each of the backscattered carrier signals is received and processed simultaneously.

36. The method of claim 32, wherein the step of transmitting a carrier signal comprises regularly hopping the carrier signal to a different frequency.

37. The method of claim 32, wherein n is an integer from 1 to 5.