Secure wireless key system and method with dynamically adjustable modulation

Patent metadata

Field	Value
Publication number	US-11217049-B2
Application number	US-202017092209-A
Country	US
Kind code	B2
Filing date	Nov 6, 2020
Priority date	Nov 7, 2019
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

A system and method are described for securing a vehicle. For example, one embodiment of a method comprises: generating a secret related to a radio frequency (RF) signal characteristic to be transmitted by a key fob; securely sharing the secret between a vehicle and a wireless key fob; periodically transmitting a ping signal from the vehicle in a locked or inactive state; receiving a response ping signal to the ping signal, the response ping signal transmitted by the key fob; identifying at least a first RF signal characteristic associated with the response ping signal; determining whether the first RF signal characteristic is valid based on the secret; unlocking and/or activating the vehicle upon determining that the first RF signal characteristic is valid; and maintaining the locked or inactive state and/or requiring additional authentication if the first RF signal characteristic is invalid.

First claim

What is claimed is:

1. A method comprising:
generating a secret related to a radio frequency (RF) signal characteristic to be transmitted by a key fob;
securely sharing the secret between a vehicle and the key fob through a first secure wireless communication channel, the first secure wireless communication channel comprising an encrypted communication channel through an Internet of Things (IoT) service;
periodically transmitting a ping signal from the vehicle in a locked or inactive state subsequent to the sharing of the secret between the vehicle and the key fob;
resetting a timer or recording a time at which the ping signal was transmitted;
receiving a response ping signal to the ping signal, the response ping signal transmitted by the key fob;
identifying at least a first RF signal characteristic associated with the response ping signal;
determining whether the first RF signal characteristic is valid based on the secret;
determining timing data related to a time the ping signal was transmitted and a time the ping response signal was received, wherein determining the timing data comprises determining a round trip time between transmitting the ping signal and receiving the ping response signal based on a current value in the timer when the ping response signal is received or based on a difference between the time at which the ping signal was transmitted and the time at which the ping response signal was received;
determining whether the timing data is within an acceptable range;
unlocking and/or activating the vehicle upon determining both that the first RF signal characteristic is valid and that the timing data is within the acceptable range, wherein determining whether the timing data is within an acceptable range comprises determining whether the round trip time is above a specified threshold; and
maintaining the locked or inactive state and/or requiring additional authentication if either the first RF signal characteristic is invalid or the timing data is not within the acceptable range.

2. The method of claim 1 wherein the secret specifies at least one of: a frequency offset, a phase offset, or a particular type of signal modulation.

3. The method of claim 2 wherein if the secret comprises a frequency offset and/or phase offset, then the key fob is to adjust an original signal using the frequency offset or phase offset to generate the ping response signal comprising a new frequency or new phase, respectively, wherein the new frequency and/or new phase comprises the RF signal characteristic determined to be valid.

4. The method of claim 1 wherein the specified threshold is determined based on a known speed of light through air and a specified acceptable distance of a wireless key from a secure vehicle or location.

5. The method of claim 1 further comprising establishing a second secure wireless communication channel between the vehicle and the key fob, the second secure wireless communication channel comprising an encrypted Bluetooth Low Energy channel-established directly between the vehicle and the key fob.

6. The method of claim 5 wherein the ping signal and the ping response signal are transmitted over the second wireless communication channel different from the first secure wireless communication channel that was used to share the secret.

7. The method of claim 1 wherein the key fob comprises an Internet of Things (IoT) device including a memory for storing program code and data and a processor for executing the program code and processing the data to establish the first secure wireless communication channel.

8. An apparatus to lock and unlock a vehicle comprising:
a dynamic modulation selector to generate a secret related to a radio frequency (RF) signal characteristic to be transmitted by a key fob;
a secure communication module to securely share the secret with the key fob through a first secure wireless communication channel, the first secure wireless communication channel comprising an encrypted communication channel through an Internet of Things (IoT) service;
a transmitter to transmit a ping signal from the vehicle in a locked or inactive state subsequent to sharing of the secret between the secure communication module and the key fob;
a receiver to receive a response ping signal to the ping signal, the response ping signal transmitted by the key fob;
an RF characteristic detector and validator to identify at least a first RF signal characteristic associated with the response ping signal and to determine whether the first RF signal characteristic is valid based on the secret;
timing circuitry to determine timing data related to a time the ping signal was transmitted and a time the ping response signal was received, the timing circuitry comprising a timer to be reset or timestamp recorder to record a time at which the ping signal was transmitted, wherein to determine the timing data the timing circuitry is to determine a round trip time between transmitting the ping signal and receiving the ping response signal based on a current value in the timer when the ping response signal is received or based on a difference between the time at which the ping signal was transmitted and the time at which the ping response signal was received;
timing validation circuitry to determine whether the timing data is within an acceptable range, wherein determining whether the timing data is within an acceptable range comprises determining whether the round trip time is above a specified threshold;
a lock manager to unlock and/or activate the vehicle upon determining both that the first RF signal characteristic is valid and that the timing data is within the acceptable range; and
the lock manager to maintain the locked or inactive state and/or require additional authentication if either the first RF signal characteristic is invalid or the timing data is not within the acceptable range.

9. The apparatus of claim 8 wherein the secret specifies at least one of: a frequency offset, a phase offset, or a particular type of signal modulation.

10. The apparatus of claim 9 wherein if the secret comprises a frequency offset and/or phase offset, then the key fob is to adjust an original signal using the frequency offset or phase offset to generate the response signal comprising a new frequency or new phase, respectively, wherein the new frequency and/or new phase comprises the RF signal characteristic determined to be valid.

11. The apparatus of claim 8 wherein the specified threshold is determined based on a known speed of light through air and a specified acceptable distance of a wireless key from a secure vehicle or location.

12. The apparatus of claim 8 wherein the transmitter and/or the receiver is to establish a second secure wireless communication channel between the vehicle and the key fob, the second secure wireless communication channel comprising an encrypted Bluetooth Low Energy channel established directly between the vehicle and the key fob.

13. The apparatus of claim 12 wherein the ping signal and the ping response signal are transmitted over second wireless communication channel different from the first secure wireless communication channel that was used to share the secret.

14. The apparatus of claim 8 wherein the key fob comprises an Internet of Things (IoT) device including a memory for storing program code and data and a processor for executing the program code and processing the data to establish the first secure wireless communication channel.

15. An apparatus comprising:
a secure wireless communication module to securely receive a shared secret related to a radio frequency (RF) signal c

Assignees

• Afero Inc

Inventors

• Bartlett Scott
• Kough Doug

Classifications

• G07C2009/00769

  with data transmission performed by wireless means · CPC title

• G07C2009/00555

  comprising means to detect or avoid relay attacks · CPC title

• G07C2009/00793

  by Hertzian waves · CPC title

• G07C2009/00984

  fob · CPC title

• G07C2009/00388

  code verification carried out according to the challenge/response method · CPC title