Patent ID: 7478751
Filing Date: 2009-01-20
Classification: G06K,G06Q,G07D,G07F

Abstract:
1. A reader system for authenticating an object, the object comprising a magnetic medium possessing a remanent noise characteristic component and recorded data component, the reader system configured to read the object when the object is moved in proximity to the reader system at a velocity, the reader system comprising: a sensing unit configured to generate a signal indicative of the magnetic field of the magnetic medium; an analog-to-digital converter (ADC) in communication with the sensing unit and configured to digitize the signal indicative of the magnetic field of the magnetic medium; a filter, in communication with the ADC, configured to filter out the recorded data component of the digitized signal and configured to preserve the remanent noise characteristic component of the digitized signal; a data extraction unit, in communication with the ADC and the filter, configured to measure at least bit duration and peak location; and an authentication extraction unit, in communication with the filter and the data extraction unit, and configured to extract a set of scaled samples from the output of the filter representative of the remanent noise characteristic.