| 摘要 |
<p>A method of controlling access to a space closed by a door, comprises providing 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 at least one communications unit to another second unit. The second communications unit checks the identification code and transmits an acknowledgement code at a second transmission power lower than the first transmission power, to the first communications unit if the check of the identification code was successful. The first communications unit then transmits an access code to the second communications unit. After a successful check of the access code by the second communications unit, access is freed.</p> |
