METHOD AND APPARATUS FOR AUTHENTICATING A MAGNETIC FINGERPRINT SIGNAL USING AN ADAPTIVE ANALOG TO DIGITAL CONVERTER

摘要

A system for verifying the authenticity of data contained in a magnetic medium using the remanent noise characteristics of the magnetic medium. One embodiment of the invention includes an over-sampled modulator and at least one channel in communication with an output of the over-sampled modulator. The at least one channel is configured to filter the output of the over-sampled modulator and the at least one channel is configured to vary the bandwidth of the filter applied to the output of the over-sampled modulator in response to variations in the bandwidth of the signal generated by the sensing unit.