US Patent 7532608 Electronic anti-theft system with correlated transmit/receive antennas

An electronic anti-theft system and an operating method have transmit/receive antennas of different frequencies that are electrically correlated with one another. The data communication of access code signals takes place at least partially via shared signal paths. A frequency decoupling of the access code signals is also performed. The transmit/receive antennas are preferably also embodied as structurally integrated. In this way a substantial simplification of the system and simultaneously also a cost optimization can be achieved.