G11B20/10398

MEASUREMENT DEVICE, MEASUREMENT METHOD, RECORDING MEDIUM, AND PHONOGRAPH RECORD
20230109304 · 2023-04-06 ·

A playback device (measurement device) in a record playback system including a record player and the playback device measures a frequency characteristic of each of a plurality of input signals which are input from the record player to the playback device when a plurality of test signals for measuring a characteristic of the record playback system are played back by the record player, the plurality of test signals being recorded on a phonograph record, the plurality of input signals corresponding to the plurality of test signals recorded; calculates a measurement error between the frequency characteristic of each of the plurality of input signals measured and a predetermined frequency characteristic; selects a frequency characteristic of which the measurement error is smallest from among the frequency characteristics of the plurality of input signals, as a measurement result of the record playback system; and outputs the measurement result selected.

AUDIO SIGNAL PROCESSING DEVICE, AUDIO SIGNAL PROCESSING METHOD, AND RECORDING MEDIUM
20230144494 · 2023-05-11 ·

An audio signal processing device includes a first input terminal which receives an audio signal from a record player, a memory which stores a correction parameter for audio signal processing and characteristic information indicating the characteristic of an audio signal for measurement, a signal processing circuit which performs the audio signal processing on the audio signal received based on the correction parameter, and a microcomputer. The microcomputer measures the sound characteristic of the audio signal received when the audio signal for measurement recorded on a phonograph record for measurement are reproduced, generates the correction parameter based on a result of comparison between the result of the measurement and the characteristic information, and stores, in the memory, setting information and the correction parameter generated, in association with each other, the setting information indicating a setting on the audio signal processing when the measurement is performed.

Determining thermal gradient of heat-assisted magnetic recording hotspot based on timing errors
09837118 · 2017-12-05 · ·

Data is written to a magnetic recording medium of a drive using a read/write head. The read/write head has an energy source that applies a hotspot to the magnetic recording medium while recording. During the writing, a steady-state current applied to the energy source is changed by a step value. A timing error induced by the change in the steady-state current is measured based on reading back the data. A thermal gradient of the hotspot is determined based on the step value and the timing error.

Optical disc apparatus controlling irradiation position based on cross-correlation value between reproduction signal and decoded signal

In an optical disc apparatus for reproducing information recorded on a track of an optical disc, an optical head irradiates a light beam onto the track, detects a reflected light reflected by the track, and generates a reproduction signal based on the reflected light. A decoder circuit decodes the reproduction signal, and generates a decoded signal including information recorded on the track. A correlation detector circuit calculates a cross-correlation value between the reproduction signal and the decoded signal. A servo circuit detects a deviation amount of an irradiation position of the light beam onto the track, from the reproduction signal, and controls the irradiation position of the optical head based on the cross-correlation value and the deviation amount.

Precompensation based on nearby data

A circuit may be configured to precompensate the storage of data on a storage device. The magnitude and polarity of the precompensated time adjustment can be determined by looking up data patterns of storage regions in a table. A boundary can include storage regions of the device used to determine the precompensation.

Timing loop for adjacent track interference cancellation

In one implementation, the disclosure provides a system including a first circuit to compute a timing error based on a received error signal and an estimated interference signal and a timing loop filter to output a frequency offset and a phase shift based on the timing error received as input. The system also includes a phase accumulator to accumulate at least a phase shift to generate a sample index and phase and an interpolation filter to generate samples of a side track signal using the sample index and phase.

Clock data recovery in multilane data receiver
10347283 · 2019-07-09 · ·

Methods and systems are described for obtaining, at a phase-error aggregator, a plurality of data-derived phase-error signals for two or more data lanes of a multi-wire bus, each data-derived phase-error signal generated using at least (i) a phase of one or more phases of a local oscillator signal and (ii) a corresponding data signal associated with one of the two or more data lanes, generating a composite phase-error signal representing a combination of the two or more obtained data-derived phase-error signals, receiving the composite phase-error signal at a loop filter responsively generating an oscillator control signal, and receiving the oscillator control signal at a local oscillator and responsively adjusting a timing of the local oscillator to adjust the one or more phases of the local oscillator signal.

CLOCK DATA RECOVERY IN MULTILANE DATA RECEIVER
20190130942 · 2019-05-02 ·

Methods and systems are described for obtaining, at a phase-error aggregator, a plurality of data-derived phase-error signals for two or more data lanes of a multi-wire bus, each data-derived phase-error signal generated using at least (i) a phase of one or more phases of a local oscillator signal and (ii) a corresponding data signal associated with one of the two or more data lanes, generating a composite phase-error signal representing a combination of the two or more obtained data-derived phase-error signals, receiving the composite phase-error signal at a loop filter responsively generating an oscillator control signal, and receiving the oscillator control signal at a local oscillator and responsively adjusting a timing of the local oscillator to adjust the one or more phases of the local oscillator signal.

Audio signal processing device, audio signal processing method, and recording medium

An audio signal processing device includes a first input terminal which receives an audio signal from a record player, a memory which stores a correction parameter for audio signal processing and characteristic information indicating the characteristic of an audio signal for measurement, a signal processing circuit which performs the audio signal processing on the audio signal received based on the correction parameter, and a microcomputer. The microcomputer measures the sound characteristic of the audio signal received when the audio signal for measurement recorded on a phonograph record for measurement are reproduced, generates the correction parameter based on a result of comparison between the result of the measurement and the characteristic information, and stores, in the memory, setting information and the correction parameter generated, in association with each other, the setting information indicating a setting on the audio signal processing when the measurement is performed.

Measurement device, measurement method, recording medium, and phonograph record

A playback device (measurement device) in a record playback system including a record player and the playback device measures a frequency characteristic of each of a plurality of input signals which are input from the record player to the playback device when a plurality of test signals for measuring a characteristic of the record playback system are played back by the record player, the plurality of test signals being recorded on a phonograph record, the plurality of input signals corresponding to the plurality of test signals recorded; calculates a measurement error between the frequency characteristic of each of the plurality of input signals measured and a predetermined frequency characteristic; selects a frequency characteristic of which the measurement error is smallest from among the frequency characteristics of the plurality of input signals, as a measurement result of the record playback system; and outputs the measurement result selected.