JP2000182328A5

JP2000182328A5 -

Info

Publication number: JP2000182328A5
Application number: JP1998356393A
Authority: JP
Filing date: 1998-12-15
Publication date: 2005-03-17
Anticipated expiration: 2018-12-15

Description

【発明の名称】波形等化回路及びデータ再生装置Patent application title: Waveform equalization circuit and data reproduction apparatus

【０００４】
【課題を解決するための手段】
本発明の波形等化器は、記録単位毎に固定のパターンが予め記録された記録媒体から読み取られた読取信号に対して波形等化を行って等化補正読取信号を得る波形等化器であって、読取信号中の固定のパターンに対応する部分の信号レベルに応じてリミットレベルを設定する設定手段と、読取信号の振幅レベルをリミットレベルにて制限して振幅制限読取信号を得る振幅制限手段と、振幅制限読取信号をフィルタリング処理したものを等化補正読取信号として出力するフィルタと、からなることを特徴としている。
かかる本発明の波形等化器によれば、記録媒体からの読取信号中の固定のパターンに対応する部分の信号レベルに応じてリミットレベルを設定することによりリミットレベルを実際の読取信号に対する適切値として得ることができるので、そのリミットレベルを用いて固定のパターン以外の読取信号の振幅レベルを制限すれば、振幅制限された信号に対してフィルタで高域強調を行なう際の符号間干渉を確実に防止することができる。[0004]
[Means for Solving the Problems]
The waveform equalizer according to the present invention is a waveform equalizer that performs waveform equalization on a read signal read from a recording medium in which a fixed pattern is recorded in advance for each recording unit to obtain an equalization correction read signal. Setting means for setting the limit level according to the signal level of the portion corresponding to the fixed pattern in the read signal, and the amplitude limit for obtaining the amplitude limited read signal by limiting the amplitude level of the read signal at the limit level The present invention is characterized in that it comprises: means; and a filter for filtering the amplitude limited read signal and outputting the result as an equalization correction read signal.
According to the waveform equalizer of the present invention, the limit level is set to an appropriate value for the actual read signal by setting the limit level according to the signal level of the portion corresponding to the fixed pattern in the read signal from the recording medium. Therefore, if the amplitude level of the read signal other than the fixed pattern is limited by using the limit level, the inter-symbol interference when the high band emphasis is performed by the filter on the amplitude limited signal is assured. Can be prevented.

【０００５】
また、本発明の波形等化器は、記録単位毎に固定のパターンが予め記録された記録媒体から読み取られた読取信号に対して波形等化を行って等化補正読取信号を得る波形等化器であって、読取信号中の固定のパターンに対応する部分の信号レベルに応じて読取信号のレベルを調整するレベル調整手段と、レベル調整手段によってレベル調整された読取信号の振幅レベルを固定リミットレベルにて制限して振幅制限読取信号を得る振幅制限手段と、振幅制限読取信号をフィルタリング処理したものを等化補正読取信号として出力するフィルタと、からなることを特徴としている。
かかる本発明の波形等化器によれば、記録媒体からの読取信号中の固定のパターンに対応する部分の信号レベルに応じて読取信号のレベルを調整することにより固定のリミットレベルに対する実際の読取信号を適切値として得ることができるので、そのレベル調整した読取信号の振幅を固定のリミットレベルを用いて制限すれば、振幅制限された信号に対してフィルタで高域強調を行なう際の符号間干渉を確実に防止することができる。[0005]
Further, according to the waveform equalizer of the present invention, waveform equalization is performed on a read signal read from a recording medium in which a fixed pattern is previously recorded for each recording unit to obtain an equalization correction read signal. Adjustment means for adjusting the level of the read signal according to the signal level of the portion corresponding to the fixed pattern in the read signal, and the amplitude level of the read signal adjusted by the level adjustment means is fixed limit The present invention is characterized in that it comprises amplitude limiting means for obtaining an amplitude limited read signal by level limitation and a filter for filtering the amplitude limited read signal and outputting it as an equalization correction read signal.
According to the waveform equalizer of the present invention, the actual reading for the fixed limit level is performed by adjusting the level of the read signal in accordance with the signal level of the portion corresponding to the fixed pattern in the read signal from the recording medium. Since the signal can be obtained as an appropriate value, if the amplitude of the level-adjusted read signal is limited using a fixed limit level, the inter-code emphasis when the filter is subjected to high-pass emphasis on the amplitude-limited signal Interference can be reliably prevented.

【０００６】
本発明のデータ再生装置は、記録単位毎に固定のパターンが予め記録された記録媒体から読み取られた読取信号に対して波形等化を行って等化補正読取信号を得る波形等化器を備えるデータ再生装置であって、読取信号中の固定のパターンに対応する部分の信号レベルに応じてリミットレベルを設定する設定手段と、読取信号の振幅レベルをリミットレベルにて制限して振幅制限読取信号を得る振幅制限手段と、振幅制限読取信号をフィルタリング処理したものを等化補正読取信号として出力するフィルタと、等化補正読取信号の２値を判定して、この判定結果に基づいて再生データを出力する２値判定手段と、からなることを特徴としている。[0006]
A data reproduction apparatus according to the present invention includes a waveform equalizer that performs waveform equalization on a read signal read from a recording medium in which a fixed pattern is previously recorded for each recording unit to obtain an equalization correction read signal. A data reproducing apparatus comprising: setting means for setting a limit level according to a signal level of a portion corresponding to a fixed pattern in the read signal; and an amplitude limited read signal by limiting the amplitude level of the read signal to the limit level. Amplitude limiting means for obtaining the signal, a filter for filtering the amplitude limited read signal and outputting it as an equalization correction read signal, and determining the binary value of the equalization correction read signal, and based on the determination result, the reproduction data is It is characterized in that it comprises: binary judgment means for outputting.

【０００７】
また、本発明のデータ再生装置は、記録単位毎に固定のパターンが予め記録された記録媒体から読み取られた読取信号に対して波形等化を行って等化補正読取信号を得る波形等化器を備えるデータ再生装置であって、読取信号中の固定のパターンに対応する部分の信号レベルに応じて読取信号のレベルを調整するレベル調整手段と、レベル調整手段によってレベル調整された読取信号の振幅レベルを固定リミットレベルにて制限して振幅制限読取信号を得る振幅制限手段と、振幅制限読取信号をフィルタリング処理したものを等化補正読取信号として出力するフィルタと、等化補正読取信号の２値を判定して、この判定結果に基づいて再生データを出力する２値判定手段と、からなることを特徴としている。[0007]
A data reproducing apparatus according to the present invention is a waveform equalizer that performs waveform equalization on a read signal read from a recording medium in which a fixed pattern is previously recorded for each recording unit to obtain an equalization correction read signal. Data reproducing apparatus comprising: level adjusting means for adjusting the level of the read signal according to the signal level of the portion corresponding to the fixed pattern in the read signal; and amplitude of the read signal adjusted by the level adjusting means Amplitude limiting means for obtaining an amplitude limited read signal by limiting the level to a fixed limit level, a filter for filtering the amplitude limited read signal and outputting it as an equalization correction read signal, and two values of an equalization correction read signal And a binary determination means for outputting reproduction data based on the determination result.

Claims

A waveform equalizer that performs waveform equalization on a read signal read from a recording medium in which a fixed pattern is previously recorded for each recording unit, and obtains an equalization correction read signal.
Setting means for setting a limit level in accordance with a signal level of a portion corresponding to the fixed pattern in the read signal;
Amplitude limiting means for obtaining an amplitude limited read signal by limiting the amplitude level of the read signal to the limit level;
And a filter for outputting a result of filtering the amplitude limited read signal as the equalization correction read signal.

The setting means includes level detection means for integrating and detecting the level of the signal of the portion corresponding to the fixed pattern in the read signal;
Holding means for holding the detection level by the level detection means at the end of the portion corresponding to the fixed pattern in the read signal and setting the limit level corresponding to the detection level held. The waveform equalizer according to claim 1, characterized in that

A waveform equalizer that performs waveform equalization on a read signal read from a recording medium in which a fixed pattern is previously recorded for each recording unit, and obtains an equalization correction read signal.
Level adjusting means for adjusting the level of the read signal according to the signal level of the portion corresponding to the fixed pattern in the read signal;
Amplitude limiting means for obtaining an amplitude limited read signal by limiting the amplitude level of the read signal level-adjusted by the level adjusting means to a fixed limit level;
And a filter for outputting a result of filtering the amplitude limited read signal as the equalization correction read signal.

The level adjustment means integrates level signal of a portion corresponding to the fixed pattern in the read signal to detect the level;
Holding means for holding the detection level by the level detection means at the end of the portion corresponding to the fixed pattern in the read signal;
4. The waveform equalization method according to claim 3, further comprising: means for comparing the detection level held by the holding means with the fixed limit level and changing the level of the read signal according to the comparison result. vessel.

A data reproduction apparatus comprising: a waveform equalizer that performs waveform equalization on a read signal read from a recording medium in which a fixed pattern is recorded in advance for each recording unit, and obtains an equalization correction read signal.
Setting means for setting a limit level in accordance with a signal level of a portion corresponding to the fixed pattern in the read signal;
Amplitude limiting means for obtaining an amplitude limited read signal by limiting the amplitude level of the read signal to the limit level;
A filter that outputs a result of filtering the amplitude limited read signal as the equalization correction read signal;
And a binary determination means for determining the binary value of the equalization correction read signal and outputting reproduction data based on the determination result.

A data reproduction apparatus comprising: a waveform equalizer that performs waveform equalization on a read signal read from a recording medium in which a fixed pattern is recorded in advance for each recording unit, and obtains an equalization correction read signal.
  Level adjusting means for adjusting the level of the read signal according to the signal level of the portion corresponding to the fixed pattern in the read signal;
  Amplitude limiting means for obtaining an amplitude limited read signal by limiting the amplitude level of the read signal level-adjusted by the level adjusting means to a fixed limit level;
  A filter that outputs a result of filtering the amplitude limited read signal as the equalization correction read signal;
  And a binary determination means for determining the binary value of the equalization correction read signal and outputting reproduction data based on the determination result.