Relay attack mitigation and prevention

摘要

This disclosure describes systems, methods, and devices related to enhanced time of flight (ToF) calculation using phase measurements. A device may identify a radiofrequency (RF) signal received from a vehicle key, wherein the RF signal comprises a command associated with a vehicle. The device may select a first subset of a frequency bandwidth. The device may perform a first time-of-flight calculation associated with the RF signal using a phase shift measurement on a first subset of frequency bandwidth. The device may determine a distance between the vehicle key and the vehicle based on the first time-of-flight calculation. The device may compare the distance to a predetermined threshold. The device may determine a status of the RF signal based on the comparison.