BLE Passive Vehicle Access Control Defending Against Relay Attacks

The patent introduces location receiver assemblies (GPS) and magnetometers as intermediary verification mechanisms. These components act as mediators that independently verify the physical proximity and location of the key fob relative to the vehicle, providing an additional layer of authentication beyond radio frequency signals. The magnetometer specifically serves as an intermediary that detects the magnetic field signature of the key fob, creating a physical verification layer that relay attacks cannot replicate.

The patent changes the verification parameters from solely radio frequency signal presence to include geographic coordinates (latitude, longitude, altitude) and magnetic field intensity. By transforming the authentication criteria into multiple physical parameters that must simultaneously match, the system makes relay attacks ineffective because attackers cannot replicate the precise spatial and magnetic field conditions required for authentication.

The patent makes the vehicle's existing communication system multi-functional by enabling it to perform both radio frequency communication and location verification through integrated location receiver assemblies. The magnetometer is incorporated into the existing key fob and vehicle communication architecture, allowing a single device to perform multiple functions: RF communication, location tracking, and magnetic field verification. This reduces the need for entirely separate verification systems.

The patent combines multiple verification functions (GPS location tracking and magnetometer detection) into a unified authentication process that operates through the existing passive entry communication channel. Rather than adding separate independent systems, the patent merges location and magnetic field verification with the RF communication system, processing all verification data through a single authentication protocol between the key fob and vehicle.