Patent ID: 8820507

Claim:
A method for implementation by one or more data processors forming part of at least one computing system comprising: receiving, by at least one data processor, data characterizing a measured electromagnetic response of at least one component of an item of currency; simulating, using at least one data processor, the measured electromagnetic response of the at least one component of the item of currency using model parameters describing an electromagnetic response of the at least one component of the item of currency; updating, using at least one data processor, the model parameters based at least on a difference between the simulated response and the received data; simulating, using at least one data processor, the measured electromagnetic response of the at least one component of the item of currency using the updated model parameters to create a second simulated signal of the at least one component of the item of currency; and classifying, using at least one data processor, the item of currency based on the second simulated signal of the at least one component of the item of currency.