Abstract: A composite antenna system for an article surveillance system, in which a plurality of differently-phased loop antennas are supplied with different currents to provide desired positioning of peaks and nulls in the near-field strength, and to produce near-zero far-field strength, as desired. In one preferred form, a smaller loop is placed near the floor and a larger loop placed above it, with the lower loop supplied with a correspondingly higher-intensity of current to provide an enhanced near-field strength near the floor, while still maintaining far-field cancellation.

Abstract: In an electronic article surveillance system, a low-power supply is used to power the system during ordinary search-and-detect operation, and the increased power needed to transmit high-power signals for deactivating the tag circuit is produced by charging up a rechargable storage device, such as a capacitor or rechargable battery, in the intervals between deactivations and using the charged-up storage device to provide the high supply power needed during deactivation, to generate the deactivation transmission.