Method and apparatus to reproduce data with an improved data error correction capability

Abstract

A method and apparatus to reproduce and/or record data from and/or to an optical recording medium. The method includes detecting a wobble signal from the optical recording medium, predicting a wobble channel state from the detected wobble signal, detecting an information signal from the optical recording medium, predicting an information channel state from the detected information signal. If a damaged section is discovered from the optical recording medium, the information signal is decoded based on the information on the wobble channel state or the information on the information channel state. Accordingly, data can be reproduced more effectively by predicting a channel state of an information (RF) signal and a channel state of a wobble signal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention will become apparent from the following detailed description of example embodiments and the claims when read in connection with the accompanying drawings, all forming a part of the disclosure of this invention. While the following written and illustrated disclosure focuses on disclosing example embodiments of the invention, it should be clearly understood that the same is by way of illustration and example only and that the invention is not limited thereto. The spirit and scope of the present invention are limited only by the terms of the appended claims. The following represents brief descriptions of the drawings, wherein:

FIG. 1 is a block diagram of a conventional apparatus to record and/or reproduce data onto and/or from an optical recording medium;

FIG. 2 is a track configuration of a conventional optical recording medium;

FIG. 3 is a track configuration of a conventional optical recording medium in which data in a certain section is damaged due to dust, fingerprints, or scratches;

FIG. 4 is a block diagram of an apparatus to record and/or reproduce data onto and/or from an optical recording medium according to an example embodiment of the present invention;

FIG. 5 is a block diagram of an apparatus to record and/or reproduce data onto and/or from an optical recording medium according to another embodiment of the present invention;

FIG. 6 illustrates a data loss model due to fingerprints, which is used to simulate data reproduction performance according to an embodiment of the present invention; and

FIG. 7 is a diagram showing a simulation result that is obtained by an application of the data loss model illustrated in FIG. 6 to both a conventional method and to a method according to an embodiment of the present invention.

Claims

1. A method of reproducing data from an optical recording medium, the method comprising: detecting a wobble signal from the optical recording medium;predicting a wobble channel state from the detected wobble signal;detecting an information signal from the optical recording medium;predicting an information channel state from the detected information signal; andif a damaged section is discovered from the optical recording medium, decoding the information signal based on the wobble channel state or the information channel state.

2. The method according to claim 1, wherein the information signal is detected from the optical recording medium using a hard decoding method or a soft decoding method.

3. The method according to claim 1, wherein the decoding comprises: partial response maximum likelihood (PRML) processing the information signal detected from the optical recording medium;demodulating the PRML-processed signal; andReed-Solomon (RS)-decoding the demodulated signal.

4. The method according to claim 3, wherein the channel state information indicates error occurrence location information, and wherein at least one of the PRML processing, the demodulating, and the RS-decoding comprises performing erasure correction of an information signal on an error occurrence location.

5. The method according to claim 1, wherein the decoding comprises: a channel detection process in which the information signal detected from the optical recording medium is processed using a soft value;a soft demodulation process in which the channel detected signal is soft-demodulated; anda channel decoding process in which the soft-demodulated signal is processed using a soft value.

6. The method according to claim 5, wherein the channel state information indicates envelope information of the wobble signal, and wherein at least one of the channel detection process, the soft demodulation process, and the channel decoding process comprises decreasing the envelope of the information signal to decrease a reliability value of the information signal according to a decrease of the envelope of the wobble signal using the envelope information of the wobble signal.

7. A computer readable medium having a program stored thereon to execute the method according to claim 1.

8. An apparatus to record and/or reproduce data onto and/or from an optical recording medium, the apparatus comprising: a wobble signal detector to detect a wobble signal from the optical recording medium;a wobble channel state predictor to predict a wobble channel state from the detected wobble signal;an information signal detector to detect an information signal from the optical recording medium; andan information channel state predictor to predict an information channel state from the detected information signal,wherein, if a damaged section is discovered from the optical recording medium, the information signal detector decodes the information signal based on the information on the wobble channel state or the information on the information channel state.

9. The apparatus according to claim 8, wherein the information signal detector decodes the information signal detected from the optical recording medium using a hard decoding method or a soft decoding method.

10. The apparatus according to claim 8, wherein the information signal detector comprises: a partial response maximum likelihood (PRML) unit PRML to process the information signal detected from the optical recording medium;a demodulator to demodulate the PRML-processed signal; anda Reed-Solomon (RS)-decoder to RS-decode the demodulated signal.

11. The apparatus according to claim 10, wherein the channel state information indicates error occurrence location information, and wherein at least one of the PRML module, the demodulator, and the RS-decoder performs erasure correction of an information signal on an error occurrence location.

12. The apparatus according to claim 8, wherein the information signal detector comprises: a channel detector to process the information signal detected from the optical recording medium using a soft value;a soft demodulator to soft-demodulate the channel detected signal; anda channel decoder to process the soft-demodulated signal using a soft value.

13. The apparatus according to claim 12, wherein the channel state information indicates envelope information of the wobble signal, and wherein at least one of the channel detector, the soft demodulator, and the channel decoder decreases the envelope of the information signal to decrease a reliability value of the information signal according to a decrease of the envelope of the wobble signal using the envelope information of the wobble signal.

14. The apparatus according to claim 12, wherein the channel detector comprises a soft output Viterbi algorithm (SOVA) module, and the channel decoder comprises a low density parity check (LDPC)-decoder or a turbo decoder.

15. A method of improving data error correction capability during data reproducing operations in which the data is reproduced from an optical recording medium, the method comprising: detecting a wobble signal, including information on a wobble channel state of the data, from a light beam reflected from the optical recording medium;detecting an information signal, including information on the information channel state of the data, from the light beam reflected from the optical recording medium; andif a damaged section is discovered from the optical recording medium, decoding the information signal based on the information on the wobble channel state or the information on the information channel state.

16. The method according to claim 15, wherein the decoding comprises decoding the information signal that is detected from the optical recording medium using a hard decoding method or a soft decoding method.

17. The method according to claim 15, wherein the decoding comprises: partial response maximum likelihood (PRML) processing the information signal detected from the optical recording medium;demodulating the PRML-processed signal; andReed-Solomon (RS)-decoding the demodulated signal.

18. The method according to claim 17, wherein the channel state information indicates error occurrence location information, and wherein at least one of the PRML processing, the demodulating, and the RS-decoding comprises performing erasure correction of an information signal on an error occurrence location.

19. The method according to claim 15, wherein the decoding comprises: a channel detection process in which the information signal detected from the optical recording medium is processed using a soft value;a soft demodulation process in which the channel detected signal is soft-demodulated; anda channel decoding process in which the soft-demodulated signal is processed using a soft value.

20. The method according to claim 19, wherein the channel state information indicates envelope information of the wobble signal, and wherein at least one of the channel detection process, the soft demodulation process, and the channel decoding process comprises decreasing the envelope of the information signal to decrease a reliability value of the information signal according to a decrease of the envelope of the wobble signal using the envelope information of the wobble signal.

21. A computer readable medium having a program stored thereon to execute the method according to claim 15.

22. An apparatus to record and/or reproduce data onto and/or from an optical recording medium, the apparatus comprising: a wobble signal detector to detect a wobble signal, including information on a wobble channel state, from the optical recording medium;an information signal detector to detect an information signal, including information on an information channel state, from the optical recording medium; andwherein, if a damaged section is discovered from the optical recording medium, the information signal detector decodes the information signal based on the information on the wobble channel state or the information on the information channel state.

23. The apparatus according to claim 22, wherein the information signal detector decodes the information signal detected from the optical recording medium using a hard decoding method or a soft decoding method.

24. The apparatus according to claim 22, wherein the information signal detector comprises: a partial response maximum likelihood (PRML) unit PRML to process the information signal detected from the optical recording medium;a demodulator to demodulate the PRML-processed signal; anda Reed-Solomon (RS)-decoder to RS-decode the demodulated signal.

25. The apparatus according to claim 24, wherein the channel state information indicates error occurrence location information, and wherein at least one of the PRML module, the demodulator, and the RS-decoder performs an erasure correction of an information signal on an error occurrence location.

26. The apparatus according to claim 22, wherein the information signal detector comprises: a channel detector to process the information signal detected from the optical recording medium using a soft value;a soft demodulator to soft-demodulate the channel detected signal; anda channel decoder to process the soft-demodulated signal using a soft value.

27. The apparatus according to claim 26, wherein the channel state information indicates envelope information of the wobble signal, and wherein at least one of the channel detector, the soft demodulator, and the channel decoder decreases the envelope of the information signal to decrease a reliability value of the information signal according to a decrease of the envelope of the wobble signal using the envelope information of the wobble signal.

28. The apparatus according to claim 26, wherein the channel detector comprises a soft output Viterbi algorithm (SOVA) module, and the channel decoder comprises a low density parity check (LDPC)-decoder or a turbo decoder.

29. The method according to claim 1, wherein the damaged section is discovered from at least one of the wobble channel state and the information channel state detected from the optical recording medium.