摘要:
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.
摘要:
A data reproduction apparatus for an optical disc system is provided. Included is an analog-to-digital converter (ADC) for sampling an input RF signal and outputting the sampled result, an adder for adding the sampled signal and an asymmetry correction signal. The added signal is output. A blank/defect detector is provided for generating a blank detection signal if no change in data is detected from the added signal during a predetermined interval of time. A correction signal generator is provided for calculating a digital sum value (DSV) from the received added signal, generating an asymmetry correction signal based on the calculated DSV, and outputting the generated asymmetry correction signal to the adder. A waveform equalizer is provided for waveform-equalizing the added signal. A decoder is provided for decoding the waveform-equalized signal and outputting the result. The correction signal corrector temporarily stops a DSV calculation operation with respect to the interval of the corresponding added signal, if the blank detection signal is output. Thus, an asymmetry of the RF signal is corrected to enhance quality of the reproduced data.
摘要:
An optical information storage medium and a method of recording and/or reproducing information on and/or from the optical information storage medium includes a lead-in area, a user data area, and a lead-out area in which data is recorded. The data that is not modified on storage media complying with the same physical format is recorded in the entire lead-in area or a portion of the lead-in area. A data recording modulation method used in the entire lead-in area or the portion of the lead-in area is different from a data recording modulation method used in a remaining area of the optical information storage medium.
摘要:
A device and method for data reproduction of an optical disk generating an optimized reference level optimizing a channel characteristic, the device includes a channel identifier which receives an input signal of an equalizer and detects an optimum level, and an adaptation process which by using the detected optimum level, updates the coefficient of the equalizer. Accordingly, the data reproduction device and method can detect a reference level value capable of maximizing the performance of a viterbi decoder and limit noise caused by tilt and other effects that may occur by the shape of a disk or a pickup apparatus.
摘要:
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.
摘要:
A method of detecting a frequency of a digital phase locked loop in an optical disc reproduction and/or recording apparatus, which includes (a) detecting an edge point of an input signal, (b) sampling a previous and following input signal on the basis of the detected edge point into a predetermined frequency, (c) counting a number of reference clock signals between the detected edge point and a sample which is positioned previously, adding a count value and an interval of time corresponding to the count value to obtain a frequency count value at the edge point, and (e) comparing the obtained frequency count value with a predetermined reference value, to enhance the frequency according to the comparison result can detect frequency having high resolution with only a reference clock frequency without heightening a frequency of a reference clock signal, to thereby enhance the quality of data. The frequency having the high resolution with only the reference clock frequency without heightening the frequency of the reference clock signal is detected, to thereby enhance the quality of data.
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 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:
An apparatus for correcting asymmetry existing in a reproduction signal corrects the asymmetry by signal-processing the reproduction signal from an optical disk in digital form. The asymmetry correction apparatus changes the threshold values for counting the sign bits of the reproduction signal and the asymmetry correction values although discontinuous intervals exist on the optical disc, thereby providing an effect of easily varying an adaptive speed with respect to the discontinuous signal.
摘要:
A method for playing back multiple kinds of optical discs includes making a decision as to whether a played back optical disc is classified into a digital video disc (DVD) or compact disc (CD) class, detecting the synchronization pattern of the identified disc class, reading a data stream from the optical disc by controlling the voltage controlled oscillation and the constant linear speed of the disc according to the identified disc class, decoding the data stream into the identified disc class according to the detected synchronization pattern, and transferring the decoded data stream to an audio/video decoder or a ROM decoder.