Abstract: A method of determining characteristics of a signal and an apparatus using the method. The apparatus for determining characteristics of a signal includes: a level detector receiving sample values of a radio frequency (RF) signal and binary data obtained by binarizing the RF signal, generating selection signals based on the binary data, classifying each of the sample values of the RF signal into one of a plurality of levels using the selection signals, and outputting average values of sample values of each level; and a signal characteristics determiner determining a characteristics value that indicates the characteristics of the RF signal using the average values of the sample values belonging to each level.

Abstract: An apparatus and method for measuring the quality of a signal on an optical disc based on level information of a viterbi decoder are provided. The signal quality measuring apparatus includes: a binary unit that generates binary signals from input RF signals; a channel identifier that receives the input RF signals and the binary signals output from the binary unit and outputs reference level values corresponding to the binary signals; and an information calculator that receives the reference level values and detects a signal quality value.

Abstract: An address information modulation method includes using a first characteristic of a first modulation method and a second characteristic of a second modulation method to modulate address information and/or additional information. Accordingly, a data amount of information, to access a disc, in a predetermined space of the disc is increased, and the modulated information is formed in a form of a wobble signal in a track. Here, the first characteristic of the first modulation method can be physical location information of an MSK-modulated signal, and the second characteristic of the second modulation method can be sign information of a second harmonic wave obtained by an HMW modulation, which synthesizes a cosine function of a basic frequency of a wobble signal with a sine function having a frequency that is a multiple of the basic frequency of the wobble signal.

Abstract: An optical pickup actuator includes a lens holder on which a plurality of object lenses to use in recording/reproducing information onto/from different kinds of optical media are mounted, a tilting unit tilting the lens holder, and a controller controlling the tilting unit to tilt the lens holder about one of the object lenses that is appropriate to use in recording/reproducing information onto/from a kind of optical medium to be used.

Abstract: A method of recording information on and/or reproducing information from an information storage medium that includes a user data area in which user data is recorded and which has first sync patterns and an additional data area located in at least one of areas before and after the user data area includes forming second sync patterns used in the additional data area which are different from the first sync patterns used in the user data area.

Abstract: An error correction method for optical discs, and more particularly, an error correction method appropriate to high density discs is provided. The error correction method adds inner parity and outer parity to an error correction block of size n byte x m x o. The method comprises the steps of obtaining a plurality of inner parity blocks (PI blocks) by segmenting the error correction block in the inner parity (PI) direction into x segments; generating e-byte PI for each of the plurality of PI blocks generated by segmenting, and adding the e-bytes to the PI blocks PIs to the PI direction; and generating f-byte outer parity (PO) in the PO direction of the error correction block, and adding the POs to the PO direction. The error correction method enhances error correction capability while maintaining a redundancy of parity signal on a level similar to conventional DVDs.

Abstract: An information storage medium has user data areas and additional data areas, and sync patterns to distinguish the additional data areas from the user data areas. The information storage medium includes a user data area in which user data is recorded and an additional data area located in at least one of areas before and after the user data area. Second sync patterns used in the additional data area are different from first sync patterns used in the user data area.

Abstract: An information storage medium has user data areas and additional data areas, and sync patterns to distinguish the additional data areas from the user data areas. The information storage medium includes a user data area in which user data is recorded and an additional data area located in at least one of areas before and after the user data area. Second sync patterns used in the additional data area are different from first sync patterns used in the user data area.

Abstract: An information storage medium has user data areas and additional data areas, and sync patterns to distinguish the additional data areas from the user data areas. The information storage medium includes a user data area in which user data is recorded and an additional data area located in at least one of areas before and after the user data area. Second sync patterns used in the additional data area are different from first sync patterns used in the user data area.

Abstract: A BCA (Burst Cutting Area) code including a unique disk code indicating the type of a disk is written in a BCA code area of the disk. If the disk is mounted into the optical disk player, the optical disk player reads data written in the BCA code area, extracts the disk code contained in the read data, and confirms the type of the disk corresponding to the extracted disk code by retrieving a disk code table in which disk codes corresponding to the types of disks are mapped.

Abstract: A method of generating and allocating codewords includes allocating one of two selectable codewords b1 and b2 as codeword “b” when a preceding codeword “a” and a following codeword “b” form a code stream X, in which the codewords b1 and b2 have opposite INV values which are parameters indicating whether the number of ‘1s’ contained in a codeword is an odd number or an even number. When the code stream of the preceding codeword “a” and the following codeword b1 is X1, and when the code stream of the preceding codeword “a” and the following codeword b2 is X2, the codewords are allocated such that the INV values of X1 and X2 are maintained to be opposite when the preceding codeword “a” or the following codeword b1 (b2) (b1 or b2) should be replaced by another codeword in compliance with a predetermined boundary condition given between codewords. The codewords are allocated so that a DC suppression capability of the code stream can be maintained.

Abstract: An apparatus and method to modulate address data of a disc type recording medium, include generating the address data, performing error correction coding of the address data and outputting coded address data, receiving the coded address data in a unit of at least two bits, generating a first modulated signal of the coded address data using a first modulation technique, generating a second modulated signal of the coded address data using a second modulating signal, and generating a unit wobble signal by synthesizing the first and second modulated signals.

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.

Abstract: An encoding and decoding apparatus and method thereof includes first and second soft encoders, a transmission channel, and first and second soft decoders. The first soft encoder performs a first soft encoding of input data to correct errors in the input data and outputting first soft-encoded data. The second soft encoder receives the first soft-encoded data, performs a second soft encoding to determine a success or failure of the encoding of the first soft-encoded data, and outputs second soft-encoded data. The first soft decoder soft-decodes data input through a transmission channel and corresponds to the second soft encoding, and outputs first soft-decoded data. The second soft decoder receives the first soft-decoded data, soft-decodes the first soft-decoded data corresponding to the first soft encoding, and outputs second soft-decoded data and additional information indicating the success or failure of the decoding of the first soft-decoded data.

Abstract: A device and method of data reproduction that can achieve a reference level optimizing the characteristic of a channel and can be applied to the reproduction of data on an optical disk are provided. According to the device and method, even when an input signal is in an abnormal state, an input level value can be initialized so that a Viterbi decoder can normally operate.

Abstract: An apparatus for detecting and correcting an error in a wobble signal, includes a window generator which generates a window signal using a phase locked wobble signal, which is generated in synchronization with a raw wobble signal rwb obtained by binarizing the wobble signal read from an optical recording medium, and a control operation unit which corrects the error in the rwb signal and outputs the corrected rwb signal where the error in the rwb signal is detected in the window signal. Accordingly, the error in the wobble signal can be detected and corrected using the window signal, thereby increasing the performance of an optical recording/reproducing system and improving a phase locked loop (PLL) circuit using the apparatus.

Abstract: A disc type recording medium on which information is recorded by forming disc tracks thereon, a method of forming the disc tracks, and a recording medium for recording a program executing the method. In the above media and method, data access can be rendered in data frame units. The disc type recording medium includes a data frame composed of a plurality of sync frames. The total number of the sync frames is determined according to the length of the innermost circumference of the disc type recording medium. Accordingly, recoding the additional information in such a data frame format prevents a reduction in a rate of detecting the additional information even when the recording medium is miniaturized.

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.

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.

Abstract: An optical recording medium has a user data area and a lead-out area each having grooves and lands formed thereon. Wobbles are formed on at least one lateral surface of the grooves of the user data area and the lead-out area, and configured such that wobble characteristics are made different between the user data area and the lead-out area. Different types of the wobbles are formed on the grooves of either the user data area or the lead-out area, thereby preventing an optical pickup that performs recording/reproducing, from deviating from the user data area. Also, in a multi-layer optical recording medium, a whole area of a recording layer is configured to have the same condition, thereby preventing deterioration in reproducing and/or recording due to a difference in light power transmittance of another recording layer.