摘要:
According to one embodiment, in an information recording and reproducing apparatus, a record data correction unit generates correction data for correcting a record waveform generated according to record data. Further, the information recording and reproducing apparatus generates discrimination data for use in pattern discrimination performed to generate the correction data, using decoded data outputted from a PRML signal processing unit and the record data, and outputs the generated discrimination data to the record data correction unit.
摘要:
There is provided a recording apparatus which modulates record data by a predetermined modulation method and records record patterns corresponding to the record data on an optical disk, including a random data generator which generates random data as the record data, a data exchange processor which performs exchange processing on the random data so as to equalize a frequency of appearance of each of the record patterns relative to the entire record patterns on the optical disk corresponding to the respective random data, a modulator which modulates the random data subjected to the exchange processing by the predetermined modulation method, an optical head which records record patterns corresponding to the modulated random data on the optical disk, and reproduces the modulated random data from the recorded record patterns, and a record learning unit which calculates correction amounts for recorded positions of the respective record patterns based on the reproduced random data.
摘要:
An optical disk device which decodes data recorded on an optical disk, comprises a first measuring unit which measure a cycle of a plurality of first synchronous signal regions VFO contained in a reproduction signal from an optical pickup, a cycle comparing unit which compares the measurement result of the first measuring unit with a first predetermined cycle, a second measuring unit which measures a cycle of a plurality of second synchronous signal regions SYNC which are contained in the reproduction signal from the optical pickup and have the cycle shorter than that of the plurality of first synchronous signal regions VFO, a cycle comparing unit which compares the measurement result of the second measuring unit with a second predetermined cycle, and an oscillator which generates a clock signal CKS for sampling the reproduction signal on the basis of the comparison results of the first and second cycle comparing units.
摘要:
A recorded stream generator generates a data block stream in synchronism with the phase of a recording clock, from the input data. The recorded stream generator further generates, for each predetermined data unit constituting the data block stream, a data phase reference pulse indicative of the phase of the data unit. An inserting section inserts a VFO signal into a predetermined amount (32 sectors) of the data block stream, the VFO signal having a length of time corresponding to a difference in phase between an wobble address phase signal and a data phase reference pulse. The inserting section thus provides a data stream DST consisting of the VFO signals and the data block streams. An LD uses light beams to record the data stream on an optical disk.
摘要:
A disk device includes a reading section which reads reflected light and outputs a read signal according to the read reflected light, a processing section which calculates an adjustment value from the read signal, performs predetermined processing on the read signal based on the adjustment value, and outputs a process signal, a detecting section which detects a reading defect in the reading section based on the read signal, a determining section which determines signal quality of the process signal output from the processing section, a storage section which stores the adjustment value calculated by the processing section, in a memory area, based on a result output from the determining section, and a controller which, when the detecting section detects the reading defect, performs control so that the adjustment value is read out of the storage section and is supplied to the processing section.
摘要:
A disk apparatus has an equalizing unit which performs PR equalization for the read signal from the disk based on a plurality of tap coefficients, a decoding unit which performs a decoding process for the equalized read signal, a calculating unit which obtains an ideal signal of the decoded read signal, and compares the ideal signal with the decoded read signal, thereby calculating an error signal E, and a control unit which groups the tap coefficients into at least a first and second coefficient groups which are groups of tap coefficients at symmetrical locations each, and determines tap coefficients of the first coefficient group in a range of a first limit value K1 according to the calculated error signal, determines tap coefficients of the second coefficient group in a range of a second limit value and supplies the determined tap coefficients to the equalizing unit.
摘要:
A disk apparatus has an equalizing unit which performs PR equalization for the read signal from the disk based on a plurality of tap coefficients, a decoding unit which performs a decoding process for the equalized read signal, a calculating unit which obtains an ideal signal of the decoded read signal, and compares the ideal signal with the decoded read signal, thereby calculating an error signal E, and a control unit which groups the tap coefficients into at least a first and second coefficient groups which are groups of tap coefficients at symmetrical locations each, and determines tap coefficients of the first coefficient group in a range of a first limit value K1 according to the calculated error signal, determines tap coefficients of the second coefficient group in a range of a second limit value and supplies the determined tap coefficients to the equalizing unit.
摘要:
There is provided an apparatus which can flexibly cope with both of a signal reproduction process for a region with high recording density and a signal reproduction process for a region with low recording density. The apparatus includes a waveform equalizing circuit which subjects data read out from an optical disk to a waveform equalizing process, a plurality of PRML processors of different classes supplied with an output signal of the waveform equalizing circuit, a switch which selects one of output signals of the plurality of PRML processors and supplies the selected output signal to a decoder, and a controller which controls the switch according to high-density and low-density regions with different recording densities of the optical disk to set a selection state in which a corresponding one of the output signals of the plurality of PRML processors is selected.
摘要:
A digital RF signal resulting from A/D conversion of an RF signal reproduced from an optical disk is compared with a plurality of set values, so that a predetermined waveform is detected from the digital RF signal. The wavelength of the detected waveform is measured, and the A/D conversion is controlled based on this wavelength. Comparing the digital RF signal with the plural set values enables high-accuracy waveform detection.
摘要:
A disk apparatus has a reading portion which reads out a plurality of frames stored in a disk and outputs a read signal, a detecting portion which determines that part of the read signal is identical to a frame synchronization code signal or determines that a deviation between a symbol of part of the read signal and a symbol of the frame synchronization code signal is within a certain time range to detect the frame synchronization code signals from the read signal, and a reproducing portion which reproduces the read signal in synchronization with the detected frame synchronization code signals.