Low power radio frequency communication

• US 9,245,159 B2
• Filed: 03/05/2013
• Issued: 01/26/2016
• Est. Priority Date: 04/05/2012
• Status: Active Grant

• Current Assignee: Duke University, Ricoh Company Limited
• Original Assignee: Duke University, Ricoh Company Limited
• Inventors: Gudan, Ken, Chemishkian, Sergey, Hull, Jonathan J., Reynolds, Matthew S.
• Primary Examiner(s): BROWN, VERNAL U
• Application Number:
  US13/786,343
• Publication Number:
  US 20140062664A1
• Time in Patent Office: 1,057 Days
• Field of Search: 340/10.1
• US Class Current: 1/1
• CPC Class Codes: G06K 19/071 the source being a field other than an interrogation field, e.g. WLAN, cellular phone network
• 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 7/10158 methods and means used by the interrogation device for reliably powering the wireless record carriers using an electromagnetic interrogation field
• CPC Class Codes: G06K 7/10207 parameter settings related to power consumption of the interrogator
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0245 according to signal strength
• CPC Class Codes: H04W 52/0274 by switching on or off the equipment or parts thereof
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method, system and tag for low power radio frequency communication is described. In one embodiment, the RF tag comprises: an access point comprising: a first antenna; a first radio coupled to the first antenna; a central processing unit coupled to the first radio; a backscatter adapter coupled to the access point via a wired communication interface, the backscatter adapter comprising a backscatter radio and a second antenna coupled to the backscatter radio for use in communicating with an RF tag in the network via backscatter.

Claims

1. An apparatus for use in radio frequency (RF) tag sensor network in which RF tags communicate via backscatter, the apparatus comprising:

an access point comprising;

a first antenna;

a first radio coupled to the first antenna;

a central processing unit (CPU) coupled to the first radio;

a network interface; and

a backscatter adapter coupled to the access point via a wired communication interface, the backscatter adapter comprising a backscatter radio and a second antenna coupled to the backscatter radio for use in communicating with an RF tag in the RF tag sensor network via backscatter, wherein the backscatter adapter comprises a demodulator coupled between the backscatter radio and the second antenna to receive a backscattered signal from the RF tag and demodulate the signal to obtain an Internet packet with a destination Internet protocol (IP) address that the backscatter adapter communicates via the wired communication interface to the access point to forward to a network via the network interface,

wherein the access point operates the first antenna and first radio as a half-duplex system and the backscatter adapter operates as a full duplex system.

2. The apparatus defined in claim 1 wherein the wired communication interface comprises a universal serial bus (USB) port.

3. The apparatus defined in claim 1 wherein the wired communication interface comprises a Power-Over-Ethernet interface.

4. The apparatus defined in claim 1 wherein the backscatter adapter comprises a modulator coupled between the backscatter radio and the second antenna.

5. The apparatus defined in claim 4 wherein the modulator is operable to transmit energy and communication data from the access point to the RF tag.

6. The apparatus defined in claim 5 wherein the energy comprises continuous wave energy or tag wake-up codes.

7. The apparatus defined in claim 1 wherein the backscatter adapter comprises a modulator coupled to the backscatter radio to transmit one selected from a group consisting of:

an acknowledgement and a command instruction.

8. The apparatus defined in claim 1 wherein the Internet packet comprises sensor data captured and transmitted via backscatter from the RF tag.

9. The apparatus defined in claim 1 wherein the first radio comprises an 802.11 radio.

10. An apparatus for use in a radio frequency (RF) tag sensor network in which RF tags communicate via backscatter, the apparatus comprising:

an access point comprising;

a first antenna;

a first radio coupled to the first antenna;

a central processing unit (CPU) coupled to the first radio;

a network interface; and

a backscatter adapter coupled to the access point via a wired communication interface, the backscatter adapter comprising;

a backscatter radio,

a modulator coupled to the backscatter radio and operable to transmit energy and communication data from the access point to the RF tag,

a demodulator coupled to the backscatter radio, and

a second antenna coupled to the modulator for use in communicating with an RF tag in the RF tag sensor network via backscatter, wherein the backscatter adapter comprises a demodulator coupled between the backscatter radio and the second antenna to receive a backscattered signal from the RF tag and demodulate the signal to obtain an Internet packet with a destination Internet protocol (IP) address that the backscatter adapter communicates via the wired communication interface to the access point to forward to a network via the network interface,

wherein the access point operates the first antenna and first radio as a half-duplex system and the backscatter adapter operates as a full duplex system.

11. The apparatus defined in claim 10 wherein the wired communication interface comprises a universal serial bus (USB) port.

12. The apparatus defined in claim 10 wherein the wired communication interface comprises a Power-Over-Ethernet interface.

13. The apparatus defined in claim 10 wherein the energy comprises continuous wave energy.

14. The apparatus defined in claim 10 wherein the energy comprises tag wake-up codes.

15. The apparatus defined in claim 10 wherein the modulator is operable to transmit one selected from a group consisting of:

an acknowledgement and a command instruction.

16. The apparatus defined in claim 10 wherein the Internet packet comprises sensor data captured and transmitted via backscatter from the RF tag.

17. The apparatus defined in claim 10 wherein the first radio comprises an 802.11 radio.