Multi-bit EAS marker powered by interrogation signal in the eight MHZ band

摘要

A multi-bit electronic article surveillance marker includes an antenna circuit and is powered by an interrogation field generated by EAS detection equipment and received by the marker's antenna circuit. The marker generates a multi-bit signal by selectively disturbing the interrogation field. The disturbances may be created by selectively short circuiting the marker's antenna circuit. All of the marker circuitry, including a coil that is part of the antenna circuit, may be provided as circuit elements formed on a semiconductor integrated circuit substrate.