ELECTRONIC ARTICLE SURVEILLANCE SYSTEM WITH ADAPTIVE FILTERING AND DIGITAL DETECTION

摘要

An electronic article surveillance (EAS) system includes an asynchronous noise suppression adaptive filter which removes asynchronous interference from the signal of interest with minimum distortion of the transients emitted when a sensitized tag is interrogated. The system also includes a synchronous noise suppression filter which removes interrogation synchronous noise from the signal of interest. The resulting EAS system increases the likelihood that a sensitized tag will be detected when one is present and reduces the occurence of false alarms.