Devices and methods for backscatter communication using one or more wireless communication protocols including Bluetooth low energy examples

• US 10,693,521 B2
• Filed: 03/08/2019
• Issued: 06/23/2020
• Est. Priority Date: 12/19/2014
• Status: Active Grant

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Reynolds, Matthew S., Ensworth, Joshua F.
• Primary Examiner(s): Huang, David S
• Application Number:
  US16/297,355
• Publication Number:
  US 20190207642A1
• Time in Patent Office: 473 Days
• 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: H04B 1/10 Means associated with receiver for limiting or suppressing noise or interference
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication

Abstract

Examples described herein include devices and methods that may facilitate interoperability between backscatter devices and wireless communication devices. For example, backscatter devices and methods for backscattering are described that provide a transmitted backscattered signal formatted in accordance with a wireless communication protocol (e.g. Bluetooth Low Energy, WiFi, IEEE 802.11, or IEEE 802.15.4). Such communication may reduce or eliminate any modifications required to wireless communication devices necessary to receive and decode backscattered signals.

Claims

1. A device comprising:

an antenna configured to receive an incident signal having a carrier frequency;

a modulator; and

a waveform generator, wherein the waveform generator is configured to provide a subcarrier frequency, and wherein the waveform generator is further configured to control the modulator to backscatter the incident signal having the carrier frequency using the subcarrier frequency to provide a backscattered signal to the antenna, the backscattered signal including a bandpass signal in a frequency range associated with a Bluetooth standard, wherein the backscattered signal comprises a packet formatted in accordance with a Bluetooth standard.

2. The device of claim 1, wherein the waveform generator is further configured to control the modulator to backscatter the incident signal having the carrier frequency using the subcarrier frequency to provide another backscattered signal to the antenna, the other backscattered signal including a bandpass signal in a frequency range associated with a WiFi standard, a Zigbee standard, or a cellular standard.

3. The device of claim 1, wherein the incident signal comprises a Bluetooth signal.

4. The device of claim 1, wherein the incident signal comprises a continuous wave signal.

5. The device of claim 1, wherein the packet comprises a Bluetooth advertising packet.

6. The device of claim 5, wherein the packet includes data collected by a sensor or other device in communication with the device.

7. The device of claim 1, wherein the frequency range associated with the Bluetooth standard corresponds to an advertising channel specified by a Bluetooth Low Energy (BLE) specification and wherein the bandpass signal comprises a frequency shift keying signal having a frequency deviation in accordance with a Bluetooth Low Energy specification.

8. The device of claim 1, wherein the incident signal having the carrier frequency is generated by a signal source disposed at a distance from the antenna.

9. The device of claim 1, wherein the modulator is configured to switch an impedance associated with the antenna to backscatter the incident signal.

10. The device of claim 1, further comprising:

a receiver coupled to the antenna, the receiver configured to provide an indication of when to start or stop backscattering based on presence, absence, or content of the incident signal.

11. The device of claim 10, wherein the receiver is configured to provide the indication to the waveform generator.

12. An apparatus comprising:

an antenna configured to receive an incident signal having a carrier frequency;

a receiver configured to detect a presence of the incident signal at the antenna;

a waveform generator, wherein the waveform generator is configured to provide a subcarrier frequency, and wherein the waveform generator is further configured to backscatter the incident signal having the carrier frequency using the subcarrier frequency to provide a backscattered signal to the antenna, the backscattered signal including a bandpass signal in a frequency range associated with a Bluetooth standard, wherein the receiver is further configured to detect energy related to the presence of the incident signal.

13. The device of claim 12, wherein the receiver is further configured to detect an absence of the incident signal.

14. The device of claim 12, wherein the receiver corresponds to a Bluetooth Low Energy (BLE) receiver configured to listen for incoming advertising packets on BLE advertising channels.

15. The device of claim 12, wherein the receiver is configured to decode all or a portion of the incident signal, wherein the incident signal comprises a Bluetooth signal.

16. The device of claim 12, wherein the receiver is further configured to determine when to provide the backscattered signal.

17. The device of claim 16, wherein the receiver is further configured to determine when to provide the backscattered signal based on a time at which the incident signal is present on the antenna.

18. A method comprising:

receiving an incident signal having a carrier frequency, the incident signal comprising at least one of a television transmission signal, a cellular communication signal, a WiFi signal, a Bluetooth signal, or a Zigbee signal;

detecting a presence of the incident signal based on energy related to the presence of the incident signal;

and backscattering the incident signal to provide a backscattered signal, wherein the backscattering comprises;

modulating an impedance associated with an antenna in accordance with data to be provided in the backscattered signal; and

mixing the carrier frequency with at least one subcarrier provided by the backscatter device.

19. The method of claim 18, wherein the backscattered signal comprises a Bluetooth packet comprising a sensor ID and associated sensor data.

20. The method of claim 18, further comprising:

listening for packets in the incident signal; and

detecting content in the packets to provide an indication of when to start stop backscattering.

21. The method of claim 20, wherein the packets in the incident signal correspond to advertising packets received on Bluetooth Low Energy (BLE) advertising channels.