Apparatus and method for correcting asymmetry of optical disk reproducing system
AssigneeSamsung Electronics Co., Ltd.
InventorsJe-Kook Kim, Young-Wook Jang, Suk-Jung Lee
Life of this patent
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Abstract
In an apparatus and a method for correcting asymmetry in an optical disk reproduction system, an analog RF signal is received from an optical diode and an asymmetry-corrected signal is output as a digital EFM signal. The apparatus includes envelope detectors for detecting upper and lower envelopes of the RF signal, a level controller for controlling the level of the sum of the upper envelope and the lower envelope and for outputting signal having the controlled level, and a comparator for comparing the level of the signal output from the level controller with the level of the RF signal and for outputting the comparison result as the digital EFM signal.
Claims9
An asymmetry correcting apparatus in an optical disk reproduction system, for correcting the asymmetry of an analog signal received from an optical diode and outputting the asymmetry-corrected signal as a digital signal, comprising:
- a first envelope detector for detecting an upper envelope of the analog signal;
- a second envelope detector for detecting a lower envelope of the analog signal;
- a level controller for controlling the level of the sun of the upper envelope and the lower envelope and for outputting a signal having the controlled level;
- and
- a comparator for comparing the level of the signal output from the level controller with the level of the analog signal, and for outputting the comparison result as the digital signal.
An asymmetry correcting method in an optical disk reproduction system, for correcting the asymmetry of an analog signal received from an optical diode and obtaining a digital signal, comprising the steps of:
- detecting an upper envelope and a lower envelope of the analog signal;
- adding the upper envelope to the lower envelope;
- obtaining a slice reference level by controlling the level of the addition result;
- determining whether the slice reference level is less than the level of the analog signal;
- determining a first logic level to be the level of the digital signal, when the level of the analog signal is larger than the slice reference level;
- and
- determining a second logic level supplementary to the first logic level to be the level of the digital signal, when the level of the analog signal is less than the slice reference level.
Dependencies are inferred from the claim text.