Abstract: An improved electronic article security system is employed for detecting the presence of a security tag within a detection zone. The system includes a transmitter for generating electromagnetic energy and, in the disclosed embodiment, a single antenna for emitting electromagnetic energy received from the transmitter to establish an electromagnetic field within the detection zone and for sensing disturbances within the electromagnetic field, including disturbances resulting from a security tag within the detection zone. A receiver is provided for processing signals from the antenna relating to sensed disturbances and for providing output signals. A data processing and control section analyzes the output signals from the receiver and determines whether a sensed disturbance within the electromagnetic field is caused by the presence of a security tag within the detection zone.

Abstract: An antenna for transmitting electromagnetic energy for deactivating a resonant tag circuit of an electronic article surveillance tag without regard to the orientation of the tag while minimizing far field radiation. The antenna includes a substantially planar dielectric substrate having a first side and a second side. The antenna also includes four substantially coplanar conductive loops on the first side of the dielectric substrate. The conductive loops are arranged in a two-by-two sequence and connected in series such that current flowing through any one of the conductive loops is out of phase with respect to current flowing in each adjacent conductive loop. The antenna also includes a ground trace on the second side of the substrate.