A system for determining an angle α between a longitudinal axis of a vehicle and an authenticator, in particular a key or a keyless entry device for a vehicle, wherein the angle α can be calculated with the system using the formula α=(dr−dl)* kw, where dr is the calculated and/or measured distance to the authenticator from an antenna mounted on the right side in or on the vehicle, dl is the calculated and/or measured distance to the authenticator from an antenna mounted on the left side on the vehicle, and kw is a correction factor for the angle calculation that is established in a vehicle-specific manner.