Antenna system for secure radio communication of data between electronic locking cylinder and central transceiver and/or broadcasting station, has expansion chamber connected with key slot of cylinder, where antennas are present in chamber

摘要

The antenna system has two antennas (B1, B2) e.g. Helix antennas, placed in a cylindrical core (C) of an electronic locking cylinder (A), where the antennas are electromagnetically shielded from each other. An expansion chamber (D) is connected with a key slot (E) of the cylinder, such that direct or indirect wave propagation is permitted through a key opening into inner- and outer sides of the cylinder. An electronic circuit analyzes and characterizes an input signal of each antenna, which is present in the chamber. The cylinder is implemented according to a DINstandard.