Wireless backscatter with time-of-flight for vehicle communication

• US 10,410,450 B1
• Filed: 06/27/2018
• Issued: 09/10/2019
• Est. Priority Date: 06/27/2018
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: DeLong, Aaron Matthew, Elangovan, Vivekanandh, Hassani, Ali, Van Wiemeersch, John Robert
• Primary Examiner(s): Brown, Vernal U
• Application Number:
  US16/020,216
• Time in Patent Office: 440 Days
• Field of Search: 340 57
• CPC Class Codes: B60C 23/02 Signalling devices actuated by tyre pressure hand-held tyre pressure gauges G01L17/00
• CPC Class Codes: B60C 23/0413 Wireless charging of active radio frequency circuits
• CPC Class Codes: B60R 25/24 using electronic identifiers containing a code not memorised by the user
• CPC Class Codes: G01S 13/74 Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
• CPC Class Codes: G01S 13/75 using transponders powered from received waves, e.g. using passive transponders , or using passive reflectors
• CPC Class Codes: G01S 13/765 with exchange of information between interrogator and responder
• CPC Class Codes: G07C 2009/00357 and the lock having more than one limited data transmission ranges
• CPC Class Codes: G07C 2009/00547 starting ignition
• CPC Class Codes: G07C 2009/00793 by Hertzian waves
• CPC Class Codes: G07C 2009/00984 fob
• CPC Class Codes: G07C 2209/63 Comprising locating means for detecting the position of the data carrier, i.e. within the vehicle or within a certain distance from the vehicle
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks

Abstract

Method and apparatus are disclosed for wireless backscatter with time-of-flight for vehicle communication. An example vehicle includes a communication module for Wi-Fi communication and a controller. The controller is to send a signal via the communication module upon identifying a passive-entry passive-start (PEPS) request and receive a backscatter signal from an electronic device. The backscatter signal is a reflection of the signal. The controller also is to determine a distance to the electronic device based upon the backscatter signal and perform the PEPS request upon determining the distance corresponds with the PEPS request.

Claims

1. A system comprising:

a key fob configured to receive LF signals, receive a Wi-Fi signal, determine signal strength identifiers of the LF signals, modulate the Wi-Fi signal to include the signal strength identifiers of the LF signals in a backscatter signal, and send the backscatter signal; and

a vehicle including;

a communication module to;

send the Wi-Fi signal and the LF signals upon identifying an access request; and

receive the backscatter signal; and

a controller to;

identify the signal strength identifiers in the LF signals;

determine a location of an electronic device based upon the signal strength identifiers; and

enable access to the vehicle responsive to determining that the location corresponds with the access request.

2. The system of claim 1, wherein the controller determines that the key fob is the electronic device responsive to determining that the location corresponds with the access request.

3. The system of claim 2, wherein the key fob includes:

a Wi-Fi antenna to receive the Wi-Fi signal and send the backscatter signal;

a LF antenna to receive the LF signals; and

circuitry to determine the signal strength identifiers of the LF signals and modulate the Wi-Fi signal to include the signal strength identifiers in the backscatter signal.

4. The system of claim 3, wherein the key fob is a passive electronic device without a battery that is energized by the Wi-Fi signal to receive the LF signals, determine the signal strength identifiers, modulate the Wi-Fi signal to generate the backscatter signal, and reflect the backscatter signal.

5. The system of claim 2, wherein the key fob is credit card-shaped.

6. The system of claim 1, wherein the vehicle includes a door handle and a handle sensor, wherein the controller is to:

identify the access request responsive to the handle sensor detecting that the door handle is engaged; and

determine that the location corresponds with the access request when the location corresponds with a second location of the door handle.

7. The system of claim 6, wherein, to perform the access request, the controller unlocks a door corresponding to the door handle.

8. The system of claim 1, wherein the controller is to detect a relay attack that amplified the backscatter signal responsive to determining that the location does not correspond with the access request.

9. The system of claim 8, wherein the controller is to prevent performance of the access request responsive to detecting the relay attack that amplified the backscatter signal.

10. A system comprising:

a key fob of a user, the key fob including;

a Wi-Fi antenna to receive a Wi-Fi signal and send a backscatter signal;

a LF antenna to receive LF signals; and

circuitry to determine signal strength identifiers of the LF signals and modulate the Wi-Fi signal to include the signal strength identifiers in the backscatter signal; and

a vehicle including;

a communication module to;

send the Wi-Fi signal and the LF signals upon identifying an access request; and

receive the backscatter signal that is a modified reflection of the Wi-Fi signal and includes the signal strength identifiers of the LF signals; and

a controller to;

determine a location of an electronic device based upon the signal strength identifiers;

determine that the key fob is the electronic device responsive to determining that the location corresponds with the access request; and

enable access responsive to the location corresponding with the access request.

11. The system of claim 10, wherein the key fob is a passive electronic device without a battery that is energized by the Wi-Fi signal to:

receive the LF signals;

determine the signal strength identifiers;

modulate the Wi-Fi signal to generate the backscatter signal; and

reflect the backscatter signal.

12. The system of claim 10, wherein the key fob is credit-card shaped.

13. The system of claim 10, wherein the vehicle includes a door handle and a handle sensor, wherein the controller is to:

identify the access request responsive to the handle sensor detecting that the door handle is engaged; and

determine that the location corresponds with the access request when the location corresponds with a second location of the door handle.

14. The system of claim 13, wherein, to perform the access request, the controller unlocks a door corresponding to the door handle.

15. The system of claim 10, wherein the controller is to detect a relay attack that amplified the backscatter signal responsive to determining that the location does not correspond with the access request.

16. The system of claim 15, wherein the controller is to prevent performance of the access request responsive to detecting detect the relay attack that amplified the backscatter signal.