, radio signals are transmitted to the locking system. Smart keys can be used to unlock and lock vehicle doors and to start the vehicle. The radio signals they transmit are received by several antennas mounted on the car, and the transmitted information is used for authentication
. One method used inautomotive technology is Passive Entry Passive Start (PEPS), which works with Bluetooth Low Energy
(BLE). Smart keys can also be used as room keys in hotels, as customer identifiers or for other locking systems.