Patent ID: 6757342
Filing Date: 2004-06-29
Classification: G11B,H04L

Abstract:
A data demodulating method in which binary data are defined by a pulse code modulated signal composed of a combination of a high and a low frequency signals, data for one character are produced with a predetermined number of bits of said binary data and a parity bit, said binary data is demodulated by detecting whether or not a peak point exists within a predetermined time interval distance in a reproduced signal waveform obtained by reproducing a recorded data signal, comprising steps of:defining a character time interval distance for one character of said recorded data as a predetermined range by a predetermined number of bits; converting said reproduced signal waveform to digital data by A/D conversion; detecting all the peaks in said digitized reproduced signal waveform and measuring a time interval distance between said peaks to create peak interval distance values; adding each of said peak interval distance values successively; and determining the end of one character with a peak position in said character time interval distance for one character to demodulate the data for one character.