ADIP demodulation method and apparatus

• US 20080013429A1
• Filed: 09/20/2007
• Published: 01/17/2008
• Est. Priority Date: 07/24/2002
• Status: Abandoned Application

• Current Assignee: Hao-Cheng Chen, Wen-Yi Wu
• Original Assignee: Hao-Cheng Chen, Wen-Yi Wu
• Inventors: Wu, Wen-Yi, Chen, Hao-Cheng
• Application Number:
  US11/902,310
• Publication Number:
  US 20080013429A1
• Time in Patent Office: Days
• US Class Current: 369/53.34
• CPC Class Codes: G11B 7/0053 Reproducing non-user data, e.g. wobbled address, prepits, BCA

Abstract

An ADIP demodulation method and apparatus, which are used in an optical disk driver to generate the ADIP information according to a wobble signal. The apparatus includes a slicing unit for receiving the wobble signal and generating a wobble pulse, a phase locked loop for generating a reference wobble signal with the same frequency and phase as the wobble pulse and a reference clock with frequency higher than the wobble pulse, a channel bit generator for generating a channel bit signal according to the reference wobble signal and the wobble pulse, and a decoder for decoding to ADIP information according to the channel bit signal. The channel bit generator generates a difference signal between the wobble pulse and the reference wobble signal, and outputs the channel bit signal according to the difference signal.

Claims

1. An ADIP demodulation apparatus for providing ADIP information according to a wobble signal modulated with the ADIP information, the ADIP demodulation apparatus comprising:

a digitize unit for receiving the wobble signal and generating a wobble pulse;

a phase locked loop for generating a reference wobble signal according to the wobble pulse;

an ADIP channel bit determination unit for determining an ADIP channel bit according to the reference wobble signal and the wobble pulse; and

a decoder for decoding the ADIP channel bit to generate the ADIP information.

2. The ADIP demodulation apparatus according to claim 1, wherein the ADIP channel bit determination unit comprises:

a comparator for comparing the wobble pulse and the reference wobble signal and generating a difference signal;

a counter for counting the width of high level of the difference signal corresponding to a period of the reference wobble signal using a counting clock and outputting a count value; and

a decision unit for comparing the count value with a threshold value and then outputting the ADIP channel bit.

3. The ADIP demodulation apparatus according to claim 2, further comprising a reference clock generator for generating the counting clock according to the wobble pulse.

4. The ADIP demodulation apparatus according to claim 2, wherein the comparator is an XOR gate.

5. The ADIP demodulation apparatus according to claim 2, wherein the ADIP channel bit determination unit further comprises:

an edge generator for generating an edge signal according to the reference wobble signal;

wherein the counter cleans the count value according to the edge signal.

6. An ADIP demodulation method for providing ADIP information according to a wobble signal modulated with the ADIP information, the ADIP demodulation method comprising the steps of:

generating a wobble pulse by digitizing the wobble signal;

generating a reference wobble signal according to the wobble pulse;

determining an ADIP channel bit according to the reference wobble signal and the wobble pulse; and

decoding the ADIP channel bit to generate the ADIP information.

7. The ADIP demodulation method according to claim 6, wherein the step of determining an ADIP channel bit comprises:

generating a difference signal by comparing the wobble pulse with the reference wobble signal;

counting the width of high level of the difference signal corresponding to a period of the reference wobble signal using a counting clock and outputting a count value; and

comparing the count value with a threshold value and then outputting the ADIP channel bit.

8. The ADIP demodulation method according to claim 7, wherein the counting clock is generated according to the wobble pulse.

9. The ADIP demodulation method according to claim 7, wherein the step of generating the difference signal by comparing the wobble pulse with the reference wobble signal is performed by an XOR gate.

10. The ADIP demodulation method according to claim 7, wherein the step of determining an ADIP channel bit further comprises:

generating an edge signal according to the reference wobble signal; and

cleaning the count value according to the edge signal.