Vehicle Access Authorization Using Multi-Transceiver Relay Checks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current keyless entry systems are vulnerable to relay attacks, which allow thieves to bypass security by relaying authentication signals between a vehicle and a key fob, even when the key fob is carried by the owner, as existing solutions like Faraday cages or additional detectors are impractical or inconvenient.
Innovation Solution
A method using a portable electronic key that determines signal strength information from both the key and the vehicle's transceivers, forming orderly sequences for consistency checks, preventing relay attacks by ensuring measurements are taken locally and not by a third party, thus preventing unauthorized access.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If passive keyless entry system is used, then convenience is improved, but vulnerability to relay attacks increases
Solution Approach 1:
The patent changes the authentication parameters from simple presence detection to multi-parameter verification including signal strength measurements (RSSI), time of flight (ToF) distance measurements, and consistency checks between multiple transceivers. This transforms the passive system into one that actively verifies authentication parameters to prevent relay attacks while maintaining automatic operation.
Solution Approach 2:
The system implements feedback mechanisms where the portable electronic key and vehicle transceivers exchange authentication data including signal strength measurements and distance information. The system verifies consistency of these feedback parameters between multiple transceivers and the key, creating a closed-loop authentication process that detects relay attacks.
2Reliability
If Faraday cage is used to block signals, then security is improved, but ease of operation deteriorates
Solution Approach 1:
Instead of blocking signals with a Faraday cage, the patent inverts the approach by using the signal characteristics themselves (strength, time of flight) as authentication parameters. The system allows signals to pass through but verifies their properties to detect relay attacks, eliminating the need for physical signal blocking devices.
3Reliability
If additional relay attack detectors are added, then security is improved, but device complexity increases
Solution Approach 1:
The patent makes the existing transceivers perform multiple functions: they not only exchange authentication codes but also measure signal strength and time of flight. This multi-functionality allows the system to detect relay attacks using existing hardware without adding dedicated detector components, reducing overall system complexity.
Solution Approach 2:
The system uses its own communication signals to perform authentication and security verification. The transceivers and portable key measure signal characteristics during normal authentication exchanges, eliminating the need for separate detection mechanisms and making the system self-sufficient for security verification.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enhances security by preventing relay attacks by ensuring that signal strength measurements are taken locally, reducing the risk of unauthorized access and improving convenience over existing solutions.
Implementation Method 1
The vehicle comprises at least two transceivers distributed at different locations, each of said transceivers being at least configured to emit at least a first signal and to receive at least the second signal from the portable electronic key
Implementation Method 2
determining, for each of said first signals, a first piece of information on the basis of at least one strength measurement of said first signal at the portable electronic key
Data Source
AI summary
A method for providing authorization to access a vehicle using a portable electronic key. The vehicle comprises two transceivers configured to emit a first signal and to receive a second signal from the portable electronic key. The authorization is subject to a successful completion of a control procedure including determining, for each of the first signals, a first piece of information based on at least one strength measurement of the first signal at the portable electronic key, determining, for the second signal, a second piece of information and checking whether first pieces of information determined for the first signals based on at least one strength measurement of the first signals at the portable electronic key are consistent with second pieces of information determined for the second signal based on at least one strength measurement of the second signal at each of the transceivers, and, if so, initiating or granting access to an unlocking procedure configured to provide the authorization.