摘要:
A scrambler and scrambling method. The scrambler has a random data generator which generates random data having a random data generation cycle based on a result obtained by multiplying at least a size of a first data frame by a result obtained by dividing a data amount of two tracks in an outermost circumference of an optical disc by a size of a second data frame. The scrambler is advantageous in generating a stable servo signal and suppressing a DC component in modulation in a high density disc system using the optical disc.
摘要:
A data modulation method to suppress a DC component using parity information of a synchronization codeword, and an apparatus for executing the method. Input data is multiplexed according to multiplexing information, the synchronization codeword including the multiplexing information for a multiplexed data stream is inserted, modulation is performed and plural modulated data streams are output, and a respective one of the modulated data streams having a DC component, which is smallest is selected from among the modulated streams. The synchronization codeword has a bit to control the parity of the codeword, and the input data is multiplexed according to whether a parity of the synchronization codeword is even or is odd. Thus, the DC component included in the modulated codeword stream may be more effectively suppressed without a decrease in a code rate.
摘要:
A method of generating error correction parity information using a parity check matrix having m rows and n columns, wherein m is a number of parity bits and n is a number of codeword bits, wherein a same fixed number of elements in each of the rows has a value of 1 and all remaining elements in each of the rows has a value of 0, and wherein a same fixed number of elements in each of the columns has a value of 1 and all remaining elements in each of the columns has a value of 0, the error correction method including generating a lower triangular matrix in 1st through k-th rows and (n−m+1)-th through (n−m+k)-th columns of the parity check matrix by performing row and column permutations on the parity check matrix, wherein k
摘要:
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.
摘要:
A physical identification data (PID) addressing method using a wobble signal, a wobble address encoding circuit, a method and circuit for detecting the wobble address and a recording medium therefor. Groove address information indicating physical identification information is phase modulated using a wobble clock signal and recorded in one of the two walls of a groove track, and land address information is phase modulated using a wobble clock signal obtained by shifting the phase of the former wobble clock signal and recorded in the other wall. That is, address information is phase modulated and recorded in each track using the wobbles having a phase difference of 90° between adjacent tracks so that a sum of wobble signals from the adjacent tracks can be a quadrature phase shift keying (QPSK) signal. Therefore, more data can be recorded in the recording medium, and since an interval in which a wobble signal disappears is not caused, recovery of a wobble clock signal can be advantageously performed.
摘要:
A method of recording and reproducing on an optical recording medium having a user data area and a lead-out area, wherein the user data area and the lead-out area each has grooves and lands formed thereon. Wobbles are formed on at least one lateral surface of 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 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/reproduction 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 a same condition, thereby preventing deterioration in reproduction and/or recording due to a difference in light power transmittance of another recording layer.
摘要:
A tilt controller controlling a tilt of an actuator of an optical pickup based on distortion-free control signals and an optical reproducing apparatus including the tilt controller. A control signal generator generates firs and second control signals to control the actuator. A reference control signal generator generates a reference control signal using the first and second control signals. A driving signal generator generates driving signals for the actuator using the first and second control signals, and the reference control signal. Protection circuits prevent the reference control signal generator from affecting first and second control signals. Accordingly, distortion of the actuator driving signals is eliminated.
摘要:
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.
摘要:
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.
摘要:
An LDPC decoding method and apparatus of LDPC decoding a codeword formed by c code bits transmitted through a channel include receiving the codeword and a p×c parity check matrix formed of 0 and 1 values, comparing the codeword with each of p rows of the parity check matrix, the rows formed with c elements, generating an R matrix by obtaining a first minimum value that is a minimum value among elements that are not 0 in each row, a second minimum value that is a second smallest value in the same row, and a location of the first minimum value, and outputting a decoded codeword formed by c code bits by determining one code bit by adding elements of each column of the R matrix.