US 2004/0165510 A1Published application

Reproduction signal processing apparatus

AssigneeMatsushita Electric Industrial Co., Ltd.

InventorsHiroyuki Nakahira, Takashi Morie

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Abstract

An analog filter is placed at a stage previous to an analog-digital converter (ADC), and a waveform equalizer is placed at a stage subsequent to the ADC. The sampling frequency of the ADC is determined by a clock generation section according to the relationship between the bit rate of an input reproduction signal and the characteristic of the analog filter. The number of taps is changed according to the relationship between the bit rate of the input reproduction signal and the characteristic of the analog filter. Further, the tap coefficients of a waveform equalizer are changed according to the height of the frequency band of the input reproduction signal. A waveform evaluation section generates a signal that evaluates a waveform equalization signal transmitted from the waveform equalizer to a Viterbi decoder, whereby adaptive waveform equalization is realized.

Claims9

Dependent claims

A reproduction signal processing apparatus which equalizes a waveform of an input reproduction signal reproduced from a recording medium and outputs a binary signal based on the equalized waveform, the apparatus comprising:

an analog filter for receiving an input reproduction signal;
an analog-digital converter for converting an output of the analog filter to a digital reproduction signal;
a clock generation section for generating a clock signal according to the relationship between a bit rate of the input reproduction signal and a characteristic of the analog filter, the clock signal being used for determining the sampling frequency of the analog-digital converter;
and
a waveform equalizer for equalizing a waveform of the digital reproduction signal,
wherein the number of taps of the waveform equalizer is changed based on the relationship between the bit rate of the input reproduction signal and the characteristic of the analog filter.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/704,691Filed 12 Nov 2003
Priority: JP 2003-04849526 Feb 2003
Published: 26 Aug 2004
Term ends: Not estimatedThe source records don’t support an estimate.

Classification4 codes

G11B 20/10009
Digital recording or reproducing: improvement or modification of read or write signals
G11B 20/10046
Improvement or modification of read or write signals: filtering or equalising, e.g. setting the tap weights of an FIR filter
G11B 2020/10981
Wherein a time constraint must be met: recording or reproducing data when the data rate or the relative speed between record carrier and…
G11B
Information storage based on relative movement between record carrier and transducer