Data modulating method and apparatus, data demodulating method and apparatus, and code arranging method

• US 7,450,035 B2
• Filed: 11/21/2007
• Issued: 11/11/2008
• Est. Priority Date: 09/27/2002
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Shim, Jae-seong, Jung, Kiu-hae, kim, Jin-han
• Primary Examiner(s): YOUNG, BRIAN K
• Application Number:
  US11/944,251
• Publication Number:
  US 20080068233A1
• Time in Patent Office: 356 Days
• Field of Search: 341/58, 341/59, 341/102, 341/103, 375/240
• US Class Current: 341/59
• CPC Class Codes: G11B 20/1426 conversion to or from block codes or representations thereof
• CPC Class Codes: H03M 5/145 Conversion to or from block codes or representations thereof

Abstract

In a data demodulating method and apparatus, and a code arranging method, a multiplexer multiplexes an input data stream divided by a predetermined length into a plurality of types of pseudo-random data streams using multiplexed information of predetermined bits by applying a predetermined multiplexing method to each of the pseudo-random data streams. An encoder RLL-modulates the plurality of types of pseudo-random data streams to create a modulated code stream including a minimum of DC components. The multiplexer generates the random data streams by inconsecutively scrambling the input data stream using the multiplexed information. The encoder weak DC-free RLL-modulates each of the multiplexed data streams without using a DC control sub code conversion table to which additional bits are added and provides a code stream including a minimum of DC components among multiplexed, RLL-modulated code streams.

Claims

1. A method for processing data recorded on a recording layer in an information storage medium, the method comprising:

performing a modulation operation of source data into a modulated code stream of code words where a minimum run length limit is confined to “

d” and

a maximum run length limit is confined to “

k”

, wherein “

d” and

“

k”

are positive integers,

wherein, the modulation operation includes changing at least one of a code word A and a code word B into another code word so that a sum of an endzero of the code word A and a leadzero of a code word B is greater than or equal to the minimum run length limit and is less than or equal to the maximum run length limit when the code word B is connected to a code word A, the code word A is a preceding code word, wherein the endzero is a number of successive zeros from least significant bits (LSBs) of the code word A to most significant bits (MSBs) and the leadzero is a number of successive zeros from most significant bits (MSBs) of the code word B to least significant bits (LSBs).

2. The method of claim 1, wherein the minimum run length limit “

d”

is 1 and the maximum run length limit “

k”

is 7, the changing comprises changing the code word A into a code word in which the least significant bit (LSB) of the code word is “

0”

when the endzero of the code word A is “

0” and

the leadzero of the code word B is “

0 ”

.

3. The method of claim 1, wherein the code words are subsequently demodulated by:

demodulating each n bit of input codewords into m-bit where n≧

m, and m and n are positive integers, of a demodulation code unit to generate a non-inverted data stream having a predetermined length; and

inconsecutively descrainbling the non-inverted data stream using multiplexed information to generate an inverted data stream.

4. The method of claim 2, wherein the descrambing of the non-inverted data stream comprises:

performing an exclusive OR operation on a first demodulation code unit and initial data that is the multiplexed information to generate first inverted data;

outputting a second demodulation code unit to a q−

1th demodulation code unit without performing an exclusive OR operation;

performing an exclusive OR operation on the first demodulation code unit and a first qth demodulation code unit of inconsecutive qth demodulation code units to generate next inverted data; and

repeating an exclusive OR operation to the final one of the remaining qth demodulation code units of the non-inverted data stream to provide the inverted data stream.

5. The method of claim 1, wherein changing at least one of a code word A and a code word B into another code word comprises changing least significant bits (LSBs) of the code word A or most significant bits (MSBs) of the code word B.