Abstract: Embodiments of the present disclosure relate to a device, a method, an apparatus and a computer-readable medium for signal equalization. According to the embodiments of the present disclosure, a balance between equalization performance and effects is achieved by using a linear equalizer and a nonlinear equalizer. In addition, signals from different uplinks are equalized using adaptive parameters, to achieve optimal equalization of various signals.

Abstract: An inter-channel linear crosstalk estimation method and apparatus and a communication system are disclosed.

Abstract: A method, apparatus, article of manufacture, and a memory structure for securely providing data for use by a hardware device of a receiver. The method utilizes a product provisioning key (PPV) held secure from other entities that can be unlocked and used with a secret value securely and unchangeably stored in the hardware device.

Abstract: Methods for adding a communication connection to a vectored group of communication connections and corresponding apparatuses are disclosed.

Abstract: An optical disc device includes an optical pickup unit which irradiates an optical disc with light and generates a signal according to light reflected from the optical disc, a playback unit which uses the signal to execute playback of the optical disc, and an adjustment unit which executes settings adjustment processing that includes a first adjustment process and a second adjustment process to adjust various settings pertaining to the playback quality of the optical disc. The adjustment unit measures a first evaluation item that serves as an indicator of whether or not it is necessary to execute the first adjustment process and a second evaluation item that serves as an indicator of whether or not it is necessary to execute the second adjustment process, omits execution of the first and second adjustment processes depending on the results of measuring the values of the first and second evaluation items, respectively.

Abstract: According to an embodiment, a signal processing apparatus includes a first signal processor, a second signal processor and a third signal processor. The first signal processor suppresses an offset component remaining in a reproduction signal read from an optical recording medium to obtain a first signal. The second signal processor suppresses a nonlinear distortion component remaining in the first signal to obtain a second signal. The third signal processor suppresses a correlation noise component remaining in the second signal to obtain a third signal.

Abstract: A ratio Xm of an information item recorded on an adjacent track relative to an information item recorded on a main track included in a first signal obtained from a first light flux having passed through a center region (6c) is different from ratios Xs1 and Xs2 of the information items recorded on the adjacent track relative to the information items recorded on the main track included in second and third signals obtained from second and third light fluxes having passed through first and second end regions (6r, 6l), and a ratio of respective gains of a first waveform equalizer (80c), a second waveform equalizer (80r), and a third waveform equalizer (80l) is determined so as to cancel the information item recorded on the adjacent track in each of frequency components of the first signal, the second signal, and the third signal.

Abstract: Aspects of the disclosure provide a signal processing circuit. The signal processing circuit includes a processing path and a zero-start module. The processing path is configured to process an electrical signal that is generated in response to reading data on a storage medium. The data includes at least a first field and a second field. The electrical signal has a first profile corresponding to the first field and has a second profile corresponding to the second field. The zero-start module is configured to detect a field change from the first field to the second field, and control the processing path to add a compensation as a function of a profile change from the first profile to the second profile to keep the processed electrical signal to have a predetermined profile in response to the detected field change.

Abstract: Provided is a recording device, including a light irradiation/receiving unit that irradiates an optical recording medium with first light and second light, and that receives backpropagating light of the second light from the optical recording medium, a recording unit that carries out recording on the optical recording medium, a playback signal generating unit that obtains a playback signal of a signal, and a stray light signal component canceling unit that generates, based on recording data, a stray light cancel signal for canceling a stray light signal component.

Abstract: According to one embodiment, there is provided a controller including an interference cancelling module, a boosting module, and a decoding module. The interference cancelling module generates a first correction signal by cancelling an interference component from an adjacent track in a signal read from a target track of a disk medium. The boosting module generates a second correction signal by boosting a low frequency component of a signal corresponding to the first correction signal. The decoding module decodes a signal based on the second correction signal.

Abstract: Inter-track interference cancelation is disclosed, including: receiving an input sequence of samples associated with a track on magnetic storage; using a processor to generate inter-track interference (ITI) data associated with a first side track including by performing a correlation between the input sequence of samples and a sequence of data associated with the first side track.

Abstract: A discrete Fourier transform circuit (201) calculates a first frequency spectrum in a predetermined frequency range from a detection signal in a predetermined segment. An expectation calculation circuit (202) calculates a second frequency spectrum corresponding to an expectation signal of a pattern of digital information that is present in the predetermined segment and obtained via an optical disc (100). A branch metric calculation circuit (203) calculates a difference between the first frequency spectrum and the second frequency spectrum. A maximum likelihood decoding circuit (207) decodes the digital information by selecting a pattern in which the difference between the first frequency spectrum and the second frequency spectrum is minimized as a decoding result.

Abstract: An apparatus generates outgoing data (OD) to be provided on an optical disk (1) in a burst cutting area (2). The burst cutting area (2) further comprises markings (3) which cause a marking frequency spectrum (MFS) when reading out the burst cutting area (2). The apparatus comprises a channel coder (4) which receives processed data (PD) and supplies the outgoing data (OD) having an outgoing data frequency spectrum (DFS) with suppressed DC-content. The apparatus further comprises a data processing device (5) which generates the processed data (PD) to obtain an outgoing frequency spectrum (DFS) wherein a frequency component causing interference with a low frequent component of the markings (3) is suppressed or not present.

Abstract: An optical disc apparatus includes an optical pickup that emits light to an optical disc and receives reflection light reflected by the optical disc, a temperature sensor for detecting ambient temperature of the optical pickup, a temperature control processing portion that performs a process corresponding to temperature information obtained by the temperature sensor, and a filter portion that performs filtering of a signal about the temperature information during a period until the temperature information detected by the temperature sensor is input to the temperature control processing portion.

Abstract: An optical disc device includes an optical pickup that causes a laser beam to be incident on an optical disc and detects a reflected beam, an A/D converter that converts into a digital signal a plurality of analog signals obtained from the reflected beam detected by the optical pickup, an error signal generating circuit that generates a servo signal for the optical pickup based on the digital signal converted by the A/D converter, a low-pass filter that removes noise of a specific band included in the servo error signal generated by the error signal generating circuit, a main processor that switches a noise removal band of the low-pass filter based on states of the optical disc, and an actuator that performs servo control for the optical pickup based on the servo error signal from which the noise has been removed by the low-pass filter.

Abstract: Provided is a recording device, including a light irradiation/receiving unit that irradiates an optical recording medium with first light and second light, and that receives backpropagating light of the second light from the optical recording medium, a recording unit that carries out recording on the optical recording medium, a playback signal generating unit that obtains a playback signal of a signal, and a stray light signal component canceling unit that generates, based on recording data, a stray light cancel signal for canceling a stray light signal component.

Abstract: Aspects of the disclosure provide a signal processing circuit to reduce signal distortions due to optical aberrations. The signal processing circuit includes a circuit configured to receive an electrical signal corresponding to a light beam reflected by a storage medium and filter the electrical signal to reduce distortions due to, for example, birefringence aberration in the light beam, and an equalizer configured to equalize the filtered electrical signal. In an example, the circuit is a median filter.

Abstract: Analog components whose characteristics greatly differ from one another are removed as much as possible from an optical disc drive. Provided are means 38, 39 for changing the sampling frequency of a pulsed read signal to a different frequency, means 40, 41 for changing the modulation clock frequency by the same ratio as the sampling frequency, and means for automatically setting the sampling frequency changing means and the modulation clock changing means based on the channel clock.

Abstract: An offset corrector of an information readout apparatus receives a digital signal DRF output from an A/D converter, and performs offset correction. The offset corrector is capable of switching between a level-correction operation that corrects the offset so that the DC level of the shortest period signal included in the readout signal assumes a zero amplitude reference and a HPF operation that matches the level of the readout signal with the zero amplitude reference. The offset corrector corrects the offset in the level correction operation during a normal reproduction, and switches to the HPF operation for offset correction when a defect judgment unit detects a defective area. The information readout apparatus is stable and has a superior performance without a symmetry deviation if there occurs a waveform fluctuation caused by a defect etc.

Abstract: An unbalanced disc determining apparatus is provided. The unbalanced disc determining apparatus includes a noise reduction unit configured to reduce noise components of a center error signal obtained from a signal configured to detect light reflected by a disc revolved by a spindle motor, and a determination unit configured to determine whether the revolving disc is unbalanced by determining whether the center error signal of which noise is reduced exceeds a reference value.

Abstract: A wobble signal extracting circuit includes: a readout signal generating circuit generating an RF signal by adding first and second detection signals corresponding to reflected light from inside and outside a recording track; a first subtractor generating a push-pull signal by subtracting the first and second detection signals, respectively; a first analog-to-digital converter (ADC) converting the RF signal to digital; a second ADC converting the push-pull signal to digital; a residual RF component generating circuit generating a residual RF signal component equivalent to the RF signal component remaining in the digitized push-pull signal; and a second subtractor generating the wobble signal by subtracting the residual RF signal component from the digitized push-pull signal. The residual RF component generating circuit generates the residual RF signal component so that it may approach the remaining RF signal component based on correlation between the wobble signal and the digitized RF signal.

Abstract: A technique capable of realizing a power saving in a device for reproducing/recording digital signals by controlling a frequency of a clock. The device for reproducing/recording digital signals includes: a difference comparing circuit for comparing a first parameter updated each time a process for one correcting block is done in a demodulating circuit with a second parameter updated each time a process of one correcting block is done in an error correcting circuit; and a circuit for switching a frequency of a master clock depending on a comparison result of the difference comparing circuit. Thereby, the frequency of the clock can be switched both when the demodulation for one correcting block is ended and when the correcting process for one correcting block is ended by using the switched master clock.

Abstract: According to the present invention, when an apparatus performs reproduction from an optical disc of a format not compatible to the apparatus, the apparatus is prevented from obtaining an incorrect address and thus causing a malfunction. A recording method according to the present invention performs first conversion of bit-inverting m number (1?m<n; m an integer) of symbols at prescribed positions of a code word coded using an error correction code by a Reed-Solomon code and including symbol C(i) [i=0, 1, 2, . . . n; n is an integer] to generate conversion information; and records the conversion information on a first recording medium.

Abstract: Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is discussed that includes a summation circuit, a data detector circuit, an error feedback circuit, and an error calculation circuit. The summation circuit subtracts a low frequency offset feedback from an input signal to yield a processing output. The data detector circuit applies a data detection algorithm to a derivative of the processing output and provides an ideal output. The error feedback circuit includes a conditional subtraction circuit that conditionally subtracts an interim low frequency offset correction signal from a delayed version of the derivative of the processing output to yield an interim factor. The error calculation circuit generates an interim low frequency offset correction signal based at least in part on the interim factor and a derivative of the ideal output.

Abstract: An optical pickup apparatus changes a propagation direction of luminous fluxes, out of a laser light reflected by a disc, in four luminous flux regions set about a laser optical axis so as to mutually disperse these luminous fluxes. A signal light region in which only a signal light is present appears on a detection surface of a photodetector. A plurality of sensors for a signal light are placed at positions irradiated with the signal light within the region. When an arithmetic process is performed on a detection signal outputted from each sensor, a DC component occurring in a tracking error signal is suppressed.

Abstract: A recording device for recording data on a rewritable optical record carrier (11). The device comprises recording means (21, 22, 25) for forming marks on the record carrier during recording operations by irradiating the record carrier with a radiation beam (24), the marks representing the data. Further, the device comprises control means (20) for controlling the recording operations and beam control means (31) for controlling a write power of the radiation beam with reference to an optimum write power by changing the write power within a predetermined write power range around the optimum write power for subsequent write cycles, each of the write cycles comprising at least one recording operation. Variation of the write power improves the overwrite quality, in particular, in the management area, such as the file system area.

Abstract: A first optical receiver circuit in an optical receiver IC, which composes an optical disk device, generates a first voltage signal VS1 indicating an amount of light of a laser beam oscillated in a multimode. A second optical receiver circuit generates a second voltage signal VS2 indicating an amount of light of an optical feedback from an optical disk. A binarization circuit extracts a band component corresponding to a predetermined frequency in VS1, and binarizes the band component, thereby obtaining a digital signal. A delay element delays a phase of the digital signal by time equivalent to a phase difference between VS1 and VS2, and outputs the phase delayed signal as a timing signal. A sample hold circuit (S/H) samples and holds the VS2 in synchronization with the timing signal. Further, A LPF eliminates a band component corresponding to the frequency from an output signal of the S/H.

Abstract: A method for generating an RFZC signal is provided. The method includes the following steps. First, an RF signal is received and the received RF signal is converted into an RF-ENVLP signal. Next, a DC offset of the RF signal is calibrated according to a variation of the RF-ENVLP signal so as to obtain a calibrated RF-ENVLP signal and obtain a gain according to the calibrated RF-ENVLP signal. Then, an RFZC signal is generated according to the calibrated RF-ENVLP signal and the gain.

Abstract: In the multi-tone demodulation (MTD) technique, even if an input bandwidth is widened to obtain a larger SNR gain, an increase in the signal to noise ration (SNR) gain cannot always be obtained due to clock jitter that increases clock noise. Also, noise is sometimes superimposed on the clock supplied to an analog to digital converter circuit (ADS) and the noise lowers the performance. Accordingly, the optical disc apparatus loosely regulates the bandwidth of a pulsed read signal; boosts the high-frequency components of a waveform of a driving signal of a laser diode; and synchronizes autonomously a driving clock of the ADC and a digital to analog converter circuit (DAC) with a clock of the pulsed read signal.

Abstract: An LPP detection unit detects an LPP from a wobble signal. A correction unit obtains a difference set by performing processing of calculating a difference in signal level between an LPP-present sync pattern portion and a non-LPP sync pattern portion having the same polarity, and executes correction on an RF signal at a timing when the LPP is detected, by using the difference set. The LPP-present sync pattern portion is a sync pattern portion obtained when the LPP is detected at the timing of the sync pattern portion positioned at the head of a sync frame of the RF signal. The non-LPP sync pattern portion is a sync pattern portion obtained when no LPP is detected at the timing of the sync pattern portion of the sync frame. In the case of reproducing information recorded on a DVD-R/RW optical disk, the occurrence of errors due to the effect of the LPP can be reduced.

Abstract: A tilt sensor includes a photodetector having a photosensitive plane and detecting a light beam in multiple areas and outputting detection signals representing its intensities and a tilt detector for generating a tilt error signal, including information about the tilt of a disk, based on the detection signals. The light beam forms a beam spot on the photosensitive plane. The beam spot includes a +first-order light area in which zero-order and +first-order light rays, diffracted by a track on the disk, are superposed, ?first-order light area in which zero-order and ?first-order light rays are superposed, and a zero-order light area which is sandwiched between the +first-order and ?first-order light areas, includes neither the +first-order nor ?first-order light ray, but includes a zero-order light ray. The photodetector generates the detection signals except for light entering an opaque area provided for at least part of the zero-order light area.

Abstract: An optical disc device including a high frequency band processing circuit for removing low frequency components of signals outputted from plural photodetectors of a pickup, and generating various kinds of signals required for recording/playback of an optical disc by digital processing after performing AD conversion by a high-speed low-bit AD converter; and a low frequency band processing circuit for removing high frequency components of the signals outputted from the respective photodetectors of the pickup, and generating various kinds of signals required for recording/playback of an optical disc by digital processing after performing AD conversion by a low-speed high-bit time-division AD converter.

Abstract: A system and method for suppressing jitter in a digital data signal in a signal processor system. The digital data signal has spaced apart byte allocation units wherein such spacing is increased such that unallocated bytes can be identified and removed from the digital data signal. The byte allocation units of the digital data signal are suppressed with a digital data signal being outputted from the signal processor system having suppressed byte allocation units to suppress the occurrence of jitter.

Abstract: A recording apparatus (1) is provided with: a recording device (11) for recording a data pattern onto a recording medium (100); a first controlling device (22) for stopping the recording; a reading device (11) for reading the data pattern which is recorded immediately before the recording is stopped, thereby obtaining a read signal; a measuring device (19) for measuring jitter of the read signal; an adjusting device (21) for adjusting a recording condition such that the jitter satisfies a desired condition, and a second controlling device (22) for restarting the recording of the data pattern by using the adjusted recording condition.

Abstract: An optical disk apparatus is provided which can: prevent an SNR deterioration attributable to an increase in read speed; overcome difficulty in separating a read signal and HF signal components; reduce laser noise; and maintain high reliability even during a high-speed read operation. An optical disk is irradiated with laser light pulsed by a high-frequency signal generated by a HF oscillator. The output of an optical detector which receives laser light reflected from the optical disk is converted into an electric pulse read signal using a current amplifier. The pulse read signal is converted into a temporally continuous read signal using a combination of an AD converter and a DA converter.

Abstract: A media defect compensation system and method may decouple effects of asymmetry from baseline error compensation computations. In some embodiments, a switching mechanism passes a baseline error signal into a baseline loop when a determination is made that a baseline error signal is not affected by asymmetry, and otherwise freezes the baseline loop when asymmetry may influence baseline error calculations.

Abstract: It is desired that the overshooting and undershooting of optical pulse waveforms of optical pickups included in optical disk devices be reduced to improve the quality of recording. Among pulses to be recorded, the trailing edge of each last pulse and the leading edge of the subsequent erase top pulse are made to almost coincide with each other. Ratio a/b, where a is the difference between erase top pulse power level Pet and erasing power level Pe and b is the difference between recording power level Pw and the erasing power level Pe, is adjusted to realize an optical pulse waveform with reduced overshooting and undershooting for each of different recording media. Erase top pulse duration Tert is switched according to different recording speeds for different recording media.

Abstract: Various embodiments of the present invention provide systems and methods for reducing head distortion. For example, various embodiments of the present invention provide storage devices that include a storage medium, a read/write head assembly, and an adaptive distortion modification circuit. The storage medium includes information that may be sensed by the read/write head assembly that is disposed in relation to the storage medium. The adaptive distortion modification circuit receives the information sensed by the read/write head assembly and adaptively estimates and implements a distortion compensation factor in the analog domain. In some instances of the aforementioned embodiments, the read/write head assembly includes a magneto resistive head. In such instances, the distortion compensation factor is designed to compensate for non-linear distortion introduced by the magneto resistive head.

Abstract: A unit to remove crosstalk in a multi-layered disk, an optical pickup including the unit, and an optical recording and/or reproducing apparatus including the optical pickup, of which the optical pickup includes: a light source; an optical path changer to change the path of light emitted from the light source; a unit to remove crosstalk; an objective lens to focus incident light on a disk; and a photodetector detecting light reflected by the disk such that the unit to remove crosstalk separates light reflected by a target recording layer of the disk from light reflected by adjacent recording layers so that the light reflected by the target recording layer and the light reflected by the adjacent recording layers do not overlap on the photodetector.

Abstract: An apparatus generates outgoing data (OD) to be provided on an optical disk (1) in a burst cutting area (2). The burst cutting area (2) further comprises markings (3) which cause a marking frequency spectrum (MFS) when reading out the burst cutting area (2). The apparatus comprises a channel coder (4) which receives processed data (PD) and supplies the outgoing data (OD) having an outgoing data frequency spectrum (DFS) with suppressed DC-content. The apparatus further comprises a data processing device (5) which generates the processed data (PD) to obtain an outgoing frequency spectrum (DFS) wherein a frequency component causing interference with a low frequent component of the markings (3) is suppressed or not present.

Abstract: An object of the invention is to provide an optical recording medium and an optical information device that enable to improve the quality of a servo signal and a reproduction signal.

Abstract: An optical disk discriminating method and an optical disk device which can detect reflected rays for making discrimination among kinds of optical disks with high accuracies. By switching a plurality of lasers and moving a spherical aberration corrector while moving an objective lens to cause it to approach or keep away from an optical disk, rays reflected light from the optical disk can be detected with high accuracies. Discrimination among the kinds of a plurality of optical disks can be made on the basis of signals generated from the detected reflected rays. This ensures that the kind of an optical disk can be determined through one operation of sweeping.

Abstract: An optical disc reproducing apparatus includes an analog-to-digital (A/D) converter which converts an analog signal obtained from an optical disc to a digital signal; an asymmetry compensator which detects and corrects an offset of the digital signal; a phase locked loop (PLL) which estimates a clock of the digital signal and compensates for a frequency error; a binary module which converts the digital signal to binary data; an equalizer which equalizes a particular frequency of the digital signal; and a channel identifier which detects a reference level of the binary module, based on an input signal of the equalizer.

Abstract: This invention involves irradiating an optical disk with laser light, pulse-driven by a high-frequency signal from an HF oscillator, and converting the output of a photo-detector that receives laser light reflected from the optical disk into an electronic pulse readout signal using a current amplifier. The pulse readout signal is converted into a temporally continuous readout signal by a peak hold circuit. The invention solves the problems of SNR deterioration of the readout signal and the difficulty of removing the impact of high-frequency modulation accompanying the increase in the readout speed factor in optical disk devices.

Abstract: The invention provides for a method and apparatus for writing data to an optical disc and comprising recovering an output signal from optical reading head, scaling the said output signal responsive to secondary data derived from the disc by way of the optical reading head and deriving a Land Pre Pits (LPP) signal for use during recording to the disc from the said scaled output signal wherein the said scaling is arranged to increase the LPP signal when the LPP is identified as located adjacent a mark on the disc of low light reflectivity.

Abstract: An apparatus generates outgoing data (OD) to be provided on an optical disk (1) in a burst cutting area (2). The burst cutting area (2) further comprises markings (3) which cause a marking frequency spectrum (MFS) when reading out the burst cutting area (2). The apparatus comprises a channel coder (4) which receives processed data (PD) and supplies the outgoing data (OD) having an outgoing data frequency spectrum (DFS) with suppressed DC-content. The apparatus further comprises a data processing device (5) which generates the processed data (PD) to obtain an outgoing frequency spectrum (DFS) wherein a frequency component causing interference with a low frequent component of the markings (3) is suppressed or not present.

Abstract: An optical disk apparatus according to the present invention includes: a rotation driving section on which an optical disk is to be mounted and which drives the optical disk so as to be rotated; a light source; an objective lens for converging light from the light source onto an optical disk mounted on the rotation driving section; a photodetector having at least two detection sections for detecting reflected light, from the optical disk, of the light; and an error signal generation section for deriving a difference signal and a sum signal of respective outputs from the two detection sections of the photodetector, adjusting an offset in at least the sum signal among the difference signal and the sum signal, and thereafter dividing the difference signal by the sum signal whose offset has been adjusted to generate a position error signal of the objective lens.

Abstract: Provided is a light-spot-position control apparatus including: a first-light-source; a second-light-source; a beam-splitter splitting a beam of the second-light-source into m beams; an optical-system allowing a first-beam of the first-light-source and the m beams to irradiate a disk-shaped recording-medium, where grooves and lands are alternately formed with an equal radial width to form the grooves in spiral/concentric shape through common-objective-lens, the optical-system allowing the three beams to irradiate the recording-medium so that an interval of m beam-spots is 1/m of track pitch; a tracking-control-mechanism tracking-controlling the beam by changing a relationship between the optical-axis and the recording-medium; a light-receiving unit individually receiving the m beams; an error-signal generator generating error-signals representing radial-position-errors of the spot-positions of the m beams with respect to the tracks based on received signals; an error-signal selector selecting at least one erro

Abstract: In three consecutive cells consisting of a preceding cell, a center cell, and a subsequent cell, a possible change rate of the amplitude of a reproduced signal for the center cell with respect to the sum of the multiple values of the preceding and subsequent cells is obtained in advance. Then, for reproduction, the sum of the multiple values of the adjacent preceding and subsequent cells is obtained with respect to each cell. The amplitude of the reproduced signal obtained at the center cell is corrected to be closer to a reference value on the basis of the obtained change rate and sum.

Abstract: A method for determining a direct current (DC) level involved in an alternating current signal is provided. The alternating current signal is transmitted from an amplifier to an A/D (analog-to-digital) converter. When any of the extreme values of the alternating current signal is beyond the input range of the A/D converter, the alternating current signal is shifted to make both of the peak and bottom values located within the input range of the A/D converter. Then, the real extreme values are realized according to the shift level(s), the relative peak and bottom values realized after the shifting procedure, and the input range of the A/D converter. Finally, the DC level is determined according to the real peak and bottom values.