US 2003/0117925 A1Published application

Reproducing apparatus

AssigneeVictor Company of Japan, Ltd.

InventorJunichiro Tonami

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Abstract

A signal of a run-length-limited code is reproduced from a recording medium. The reproduced signal is sampled to generate a sampling-resultant signal. An odd-sample signal and an even-sample signal are generated in response to the sampling-resultant signal. A first transversal filter subjects the odd-sample signal to first partial-response waveform equalization to generate an equalization-resultant odd-sample signal. The first partial-response waveform equalization depends on first tap coefficients. The first tap coefficients are controlled on a feedback basis to minimize an error of the equalization-resultant odd-sample signal. A second transversal filter subjects the even-sample signal to second partial-response waveform equalization to generate an equalization-resultant even-sample signal. The second partial-response waveform equalization depends on second tap coefficients. The second tap coefficients are controlled on a feedback basis to minimize an error of the equalization-resultant even-sample signal. The equalization-resultant odd-sample signal is decoded. The equalization-resultant even-sample signal is decoded.

A reproducing apparatus comprising:

first means for reproducing a signal of a run-length-limited code from a recording medium;
second means for sampling the signal reproduced by the first means to generate a sampling-resultant signal;
third means for generating an odd-sample signal and an even-sample signal in response to the sampling-resultant signal generated by the second means;
a first transversal filter subjecting the odd-sample signal generated by the third means to first partial-response waveform equalization to generate an equalization-resultant odd-sample signal, the first partial-response waveform equalization depending on first tap coefficients;
a second transversal filter subjecting the even-sample signal generated by the third means to second partial-response waveform equalization to generate an equalization-resultant even-sample signal, the second partial-response waveform equalization depending on second tap coefficients;
a first temporary decision device for calculating a temporary decision value of the equalization-resultant odd-sample signal generated by the first transversal filter;
a first subtracter for calculating a first difference between the temporary decision value of the equalization-resultant odd-sample signal and an actual value thereof, and generating a first error signal in response to the calculated first difference;
a second temporary decision device for calculating a temporary decision value of the equalization-resultant even-sample signal generated by the second transversal filter;
a second subtracter for calculating a second difference between the temporary decision value of the equalization-resultant even-sample signal and an actual value thereof, and generating a second error signal in response to the calculated second difference;
fourth means for controlling the first tap coefficients of the first transversal filter in response to the first error signal generated by the first subtracter;
fifth means for controlling the second tap coefficients of the second transversal filter in response to the second error signal generated by the second subtracter;
a first decoder for decoding the equalization-resultant odd-sample signal generated by the first transversal filter;
and
a second decoder for decoding the equalization-resultant even-sample signal generated by the second transversal filter.

11 more elements

Facts

Application

10/147,466Filed 17 May 2002

Priority

JP 2001-39487826 Dec 2001

Published

26 Jun 2003

Term ends

Not estimatedThe source records don’t support an estimate.

Classification9 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 20/10083
Using partial response filtering when writing the signal to the medium or reading it therefrom: pR1 or PR, i.e. partial response class 1,…
G11B 20/10092
Using partial response filtering when writing the signal to the medium or reading it therefrom: partial response PR

Abstract

Claims10