Patent ID: 10954698

Abstract:
The invention relates to a system comprising a door, in particular of a vehicle, having a door lock, a door control module that has a transmission and reception unit at the door side or is connected thereto, and having a key that is associated with the door lock and that has a transmission and reception unit at the key side, wherein the transmission and reception unit at the door side and the transmission and reception unit at the key side are configured for radio communication. The time of flight of a radio signal transmitted by the transmission and reception unit at the door side and reflected by the transmission and reception unit at the key side can be determined by means of the transmission and reception unit at the door side. Alternatively, the time of flight of a radio signal transmitted by the transmission and reception unit at the key side and reflected by the transmission and reception unit at the door side can be determined by means of the transmission and reception unit at the key side.