2.4 UWB Block

UWB functionality provides the means to detect if a relay attack is occurring between the vehicle and fob by performing a Time of Flight (ToF) distance measurement during every PEPS operation.

A relay attack is detected when the vehicle initiates a PEPS command, such as lock, start and more, which wakes up the fob via the LF link. After receiving the LF data, the fob, which is configured as a UWB verifier, initiates the ToF distance measurement with the vehicle, which is configured as a UWB prover. After the vehicle responds to the fob using the UWB link, the fob performs the ToF distance measurement. If the measured distance, sent within the PEPS message to the vehicle via the unidirectional UHF link, is beyond the configured distance threshold, then a relay attack error message displays within the GUI. The same is true if there is no UWB message response from the fob.