Recording and/or reproducing apparatus and method with a signal quality determining device and method

• US 7,477,584 B2
• Filed: 11/10/2004
• Issued: 01/13/2009
• Est. Priority Date: 11/11/2003
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Jae-wook, Shim, Jae-seong, Park, Hyun-soo, Lee, Jung-hyun, Cho, Eing-seob, Ryu, Eun-jin
• Primary Examiner(s): Agustin; Peter Vincent
• Application Number:
  US10/985,014
• Publication Number:
  US 20050128916A1
• Time in Patent Office: 1,525 Days
• Field of Search: None
• US Class Current: 369/53.31
• CPC Class Codes: G11B 19/04 Arrangements for preventing, inhibiting, or warning against double recording on the same blank or against other recording or reproducing malfunctions
• CPC Class Codes: G11B 20/10009 Improvement or modification of read or write signals
• CPC Class Codes: G11B 20/10046 filtering or equalising, e.g. setting the tap weights of an FIR filter
• CPC Class Codes: G11B 20/10296 using the Viterbi algorithm
• CPC Class Codes: G11B 7/0901 for track following only G11B7/0925, G11B7/094, G11B7/0941, G11B7/0943, G11B7/0945, G11B7/0946, G11B7/0948 take precedence
• CPC Class Codes: G11B 7/0908 for focusing only G11B7/0925, G11B7/094, G11B7/0941, G11B7/0943, G11B7/0945, G11B7/0946, G11B7/0948 take precedence
• CPC Class Codes: G11B 7/0941 Methods and circuits for servo gain or phase compensation during operation for initialising servos G11B7/0945
• CPC Class Codes: G11B 7/0945 Methods for initialising servos, start-up sequences
• CPC Class Codes: G11B 7/0956 to compensate for tilt, skew, warp or inclination of the disc, i.e. maintain the optical axis at right angles to the disc

Abstract

A recording and/or reproducing apparatus and method with signal quality determining device and a method thereof, with the signal quality determining device including a signal estimator determining a level corresponding to a sample value of the RF signal using binary data obtained from the RF signal and generating a selection signal corresponding to the determined level, a channel identifier classifying the sample value into a plurality of levels according to the selection signal and obtaining an average value of the sample values classified into each level, and a quality calculator outputting a signal quality value representing quality of the RF signal using each sample value output from the channel identifier and the average value of the sample values classified into each level. Accordingly, quality of an RF signal can be determined more exactly, and focus compensation, tilt compensation, detrack compensation, and recording signal optimization can be performed using the determined signal quality.

Claims

1. An RF signal quality determining device, comprising:

a signal estimator receiving binary data of an RF signal and estimating a value of the RF signal;

a maximum/minimum value calculator receiving the RF signal and calculating a maximum value and a minimum value of the RF signal; and

a quality calculator receiving the estimated value of the RF signal, the RF signal, the maximum value of the RF signal, and the minimum value of the RF signal and calculating a signal quality value representing a signal quality of the RF signal.

2. The device of claim 1, wherein the signal estimator comprises a predetermined type of finite impulse response (FIR) filter.

3. The device of claim 1, wherein the signal quality value is a signal to noise ratio (SNR) calculated using the estimated value of the RF signal and the RF signal.

4. The device of claim 1, wherein the signal quality value is an absolute signal to noise ratio (ASNR) calculated using the estimated value of the RF signal and the RF signal.

5. The device of claim 1, wherein the signal quality value is a peak absolute signal to noise ratio calculated using the estimated value of the RF signal and the RF signal.

6. The device of claim 1, wherein the binary data is obtained by viterbi decoding the RF signal.

7. A recording and/or reproducing apparatus, comprising:

a signal detection unit to generate an RF signal representative of information of a medium;

the RF signal quality determining device of claim 1; and

a processing unit to record and/or reproduce information to/from the medium according to the determined signal quality of the RF signal.

8. The apparatus of claim 7, further comprising a processor performing at least one of focus compensation, tilt compensation, detrack compensation, and/or recording signal optimization, based on the signal quality value.

9. A method of determining a signal quality of an RF signal, the method comprising:

obtaining an estimated value of the RF signal using binary data of the RF signal;

calculating a maximum value of the RF signal and a minimum value of the RF signal;

calculating a signal quality value representing the signal quality of the RF signal using the estimated value of the RF signal, the RF signal, the maximum value of the RF signal, and the minimum value of the RF signal.

10. The method of claim 9, wherein the obtaining of the estimated value of the RF signal comprises obtaining the estimated value of the RF signal using a predetermined type of finite impulse response (FIR) filter.

11. The method of claim 9, wherein the signal quality value is a signal to noise ratio (SNR) calculated using the estimated value of the RF signal and the RF signal.

12. The method of claim 9, wherein the signal quality value is an absolute signal to noise ratio (ASNR) calculated using the estimated value of the RF signal and the RF signal.

13. The method of claim 9, wherein the signal quality value is a peak absolute signal to noise ratio (PASNR) calculated using the estimated value of the RF signal, the RF signal, the maximum value of the RF signal, and the minimum value of the RF signal.

14. The method of claim 9, wherein the binary data is obtained by viterbi decoding the RF signal.

15. A method of recording and/or reproducing information to/from a medium, comprising:

generating an RF signal representative of information of the medium;

determining a signal quality of the RF signal using the RF signal quality determining method of claim 9; and

recording and/or reproducing information to/from the medium according to the determined signal quality of the RF signal.

16. The method of claim 15, further comprising performing at least one of focus compensation, tilt compensation, detrack compensation, and/or recording signal optimization, based on the signal quality value.