Method of controlling access to an area accessible by persons, particularly to a space closed by a door

摘要

A method of controlling access to an area accessible by persons, particularly to a space closed by a door, utilizes at least two communications units for transmitting and receiving an identification code and an access code. The identification code is transmitted at a predetermined first transmission power from a first communications unit to at least one second communications unit. The second communications unit checks the identification code and transmits an acknowledgement code at a second transmission power, which is lower than the first transmission power, from the second communications unit to the first communications unit if the check of the identification code was successful. The first communications unit transmits an access code to the second communications unit. After a successful check of the access code by the second communications unit the access is freed.