Distance-defining method for determining spatial distance between communicating stations measures phase runtime of signals by determining signal phase positions in relation to each other

摘要

A door (1) is secured by a door guardian (DG) (2), e.g. an electronic device, that can communicate with a key (5), e.g. a transponder, and can release or even actively open the door by means of corresponding actuators. Upon a request (3) or by becoming automatically active, a key fob (4) transmits a code to the DG that recognizes the code as valid or invalid. An independent claim is also included for a system for determining a distance from a partner station during a current communication.