US 11,974,133 B2
Method and system for preventing a physical layer relay attack
Ulf Björkengren, Gothenburg (SE)
Assigned to Volvo Car Corporation, Gothenburg (SE)
Filed by Volvo Car Corporation, Gothenburg (SE)
Filed on Nov. 9, 2022, as Appl. No. 17/983,468.
Application 17/983,468 is a continuation of application No. 16/935,299, filed on Jul. 22, 2020, granted, now 11,528,612.
Application 16/935,299 is a continuation of application No. 15/983,286, filed on May 18, 2018, granted, now 10,759,383, issued on Sep. 1, 2020.
Claims priority of application No. 17177018 (EP), filed on Jun. 21, 2017.
Prior Publication US 2023/0074878 A1, Mar. 9, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04W 12/12 (2021.01); B60R 25/20 (2013.01); B60R 25/24 (2013.01); F02N 11/08 (2006.01); G07C 9/00 (2020.01); H04L 9/40 (2022.01); H04W 12/08 (2021.01); H04W 12/082 (2021.01)
CPC H04W 12/12 (2013.01) [B60R 25/2072 (2013.01); B60R 25/24 (2013.01); F02N 11/0807 (2013.01); G07C 9/00174 (2013.01); G07C 9/00182 (2013.01); G07C 9/00309 (2013.01); H04L 63/1466 (2013.01); H04W 12/08 (2013.01); H04W 12/082 (2021.01); G07C 2009/00261 (2013.01); G07C 2009/00555 (2013.01); G07C 2009/00769 (2013.01); G07C 2009/00801 (2013.01); G07C 2209/63 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A method, comprising:
establishing a secure communication channel between a vehicle and a user device;
transmitting an acoustic signal comprising a first unique identity from a vehicle acoustic transducer and creating a first time stamp;
in the vehicle, receiving at least one reflected acoustic signal and creating a second time stamp upon reception, and, for the at least one reflected acoustic signal, determining a first time-of-flight;
in the user device, receiving and verifying the first unique identity transmitted by the vehicle and creating a third time stamp upon reception, generating a response signal using a previously agreed upon method for creating a second unique identity based on the received first unique identity, transmitting the response signal as an acoustic signal comprising the second unique identity and creating a fourth time stamp for the transmission event, determining a response delay time, and transmitting a radio frequency (RF) signal comprising the response delay time to the vehicle over the secure communication channel;
in the vehicle, receiving the response signal, verifying the second unique identity and creating a fifth time stamp, receiving the RF signal comprising the response delay time, and determining a second time-of-flight; and
when a difference between the first time-of-flight and the second time-of-flight is below a predetermined threshold value, authorizing the user device to send a request to the vehicle.