SIGNATURE VERIFICATION ALGORITHM

An improved signature verification method using dynamic signature characteristics in the frequency domain. Analysis of a signature in the frequency domain is employed when time domain analysis does not adequately distinguish between true signatures and forgeries. The preferred signature characteristics that are measured are two acceleration components of the pen, and the rate of change of axial pressure on the pen. More specifically, correlation functions operating on a sample and reference signature produce a correlation score. If the total correlation score is in a selected interval, then the above measured characteristics are analyzed in the frequency domain with the magnitude squared coherence function.