Patent ID: 7738326

Claim:
A wobble signal processing method used when; a light beam is irradiated onto a track of an optical disc, which has tracks formed thereon to record information spirally, formed such that the track meanders according to a wobble signal modulated to express digital information including address information by locally inserting a signal, which is different from an approximately sine wave carrier signal having a predetermined frequency, into the carrier signal according to a predetermined pattern, an original wobble signal, which includes a component corresponding to the meandering of the track and a crosstalk component caused by the meandering of adjacent tracks, is created from reflected light, and address information and timing are detected based on the original wobble signal and an information pattern is recorded on the track or an information pattern on the track is reproduced, said method comprising: a step of estimating the amplitude and phase of a crosstalk component mixed from the adjacent tracks based on the amplitude and phase of the original wobble signal created in a region in which the track meanders according to the carrier signal and on the amplitude and phase of the original wobble signal created in a region in which the track meanders according to the inserted signal; a step of obtaining a reproduced wobble signal for obtaining the address information and the estimated value of the carrier signal by subtracting the estimated value of the crosstalk component from the original wobble signal; and a step of detecting the address information and the timing from the reproduced wobble signal.