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US 2004/0174778 A1Published application
Method for reducing the noise in a wobble signal
AssigneeThomson Licensing
InventorsChristian Buchler, Uwe Reschke
Life of this patent
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AssigneeThomson Licensing
InventorsChristian Buchler, Uwe Reschke
Estimating the term…
The present invention relates to a method and a circuit for recovering information (INF) contained in a wobble track (36) of an optical storage medium (34). One aim of the invention is to describe a method within an appliance for reading from and/or writing to optical storage media (34), which can correct disturbing data signal components (AS′) in the wobble signal (TW) even when the swept frequency and the lowest signal frequency are close to one another. According to the invention, this object is achieved in that the signals (A+D, B+C) from two detector halves (1A+1D, 1B+1C) of a photodetector (1) which is used for reading the data contained in a track (36) on an optical storage medium (34) are provided with weighting factors (K1, K2) which are adjusted dynamically during operation of the appliance for reading from and/or writing to optical storage media. In order to adjust the weighting factors (K1, K2), the obtained swept-frequency signal (TW) is linked to a data signal (HF).
Method for obtaining information (INF) from a wobble track (36) of an optical storage medium (34) by producing a wobble signal (TW) from the difference between the signals from two photodetector areas (1A+1D, 1B+1C) of a photodetector (1), with the signal from one detector area (1A+1D) being provided with a weighting factor (K1), characterized in that a data signal (HF), which is obtained by summing the signals (A, B, C, D) from the photodetector (1), is linked to a data signal component (AS′) which is contained in the wobble signal (TW, TW′) and is used for automatic adjustment of the weighting factor (K1).
Circuit for obtaining information (INF) from a wobble track (36) of an optical storage medium (34) by producing a wobble signal (TW) from the difference between the signals (A+D, B+C) from two photodetector areas (1A+1D, 1B+1C) of a photodetector (1), with the signal (A+D) from one detector area (1A+1D) being provided with a weighting factor (K1), characterized in that the said circuit has an adder (3) for obtaining a data signal (HF), and a logic unit (11, 14) for linking the data signal (HF) and a data signal component (AS′) in the wobble signal (TW, TW′), the output signal from which logic unit (14) is supplied to a unit (12) for determining a weighting signal, which adjusts the weighting factor (K1).
Dependencies are inferred from the claim text.