Time of flight based security for multiple key fobs

A system for passive locking and unlocking a vehicle is described that includes a memory for storing executable instructions and a processor configured to execute the instructions to unlock the vehicle using a time of flight to transmit the trigger request between the vehicle and the first key fob. The processor receives, from a first key fob, a trigger request to unlock the vehicle, and determines, based key fob identifiers that identify the first key fob and a second key fob that is also near the vehicle, that the first and second key fobs are associated with a vehicle. The processor selects the first key fob based on a key fob characteristic. The processor evaluates the time of flight using the first key fob, and unlocks the vehicle based on the time of flight satisfying a threshold for signal transmission flight time.