公开(公告)号：US06414810B1

公开(公告)日：2002-07-02

申请号：US09301192

申请日：1999-04-28

申请人： Giacomino Bollati ,  Melchiorre Bruccoleri ,  Salvatore Portaluri ,  Luca Celant

发明人： Giacomino Bollati ,  Melchiorre Bruccoleri ,  Salvatore Portaluri ,  Luca Celant

IPC分类号： G11B5035

CPC分类号： G11B20/10046 ,  G11B2220/2516

摘要： A method of equalizing a read channel of a mass magnetic memory device comprises attenuating the low frequencies of the spectrum of the analog signal originating from an electromagnetic read transducer without boosting the high frequency harmonic components of the spectrum. The low frequencies of the spectrum of the analog input signal are attenuated with a low pass filter of an order in a range from 6 to 8 and a boost is implemented by introducing two real and opposed zeroes in the transfer function of the filter without altering the group delay.

摘要翻译： 均衡质量磁存储器件的读通道的方法包括衰减源自电磁读取换能器的模拟信号的频谱的低频，而不会增加频谱的高频谐波分量。 模拟输入信号的频谱的低频通过6至8范围内的阶数的低通滤波器衰减，并且通过在滤波器的传递函数中引入两个实数和相对的零来实现升压，而不改变 群延迟

公开(公告)号：US06445526B1

公开(公告)日：2002-09-03

申请号：US08975716

申请日：1997-11-21

申请人： Kiwamu Kobayashi ,  Tatsuya Naitoh

发明人： Kiwamu Kobayashi ,  Tatsuya Naitoh

IPC分类号： G11B5035

CPC分类号： G11B5/0086 ,  G11B5/035 ,  G11B20/10009 ,  G11B20/10046

摘要： In a reproducing apparatus, an equalizing system including a plurality of elements to be controlled is arranged to have its equalizing characteristic simply variable by controlling, with a single parameter, the plurality of elements to be controlled. Further, circuit characteristics of the equalizing system which are based on resonance frequencies and quality factors (Q) are controlled by controlling the resonance frequencies and the quality factors (Q) through the control performed with the single parameter over the plurality of elements to be controlled.

摘要翻译： 在再现装置中，包括要控制的多个元件的均衡系统被布置成通过用单个参数控制待控制的多个元件来简单地变化其均衡特性。 此外，基于谐振频率和质量因子（Q）的均衡系统的电路特性通过通过在要控制的多个元件上的单个参数执行的控制来控制谐振频率和质量因子（Q）来控制 。

公开(公告)号：US06304400B1

公开(公告)日：2001-10-16

申请号：US09264840

申请日：1999-03-08

申请人： Richard C. Schneider

发明人： Richard C. Schneider

IPC分类号： G11B5035

CPC分类号： G11B20/10046 ,  G11B5/00813 ,  G11B5/09 ,  G11B20/10009 ,  G11B20/18

摘要： Dropout produces amplitude and high frequency loss in the read signal produced by reading a magnetic tape. A system for dropout compensation includes an adaptive filter that filters the read signal using multiplicative weighting factors based on an error signal. A detector receives the adaptive filter output and produces a binary signal indicating data written onto the magnetic tape. A shaping filter receives the binary signal and produces an ideal read signal representing the read signal resulting from writing and subsequently reading the binary signal without dropout. A differencer determines the error signal by subtracting the adaptive filter output from the ideal read signal.

摘要翻译： 压差在读取磁带产生的读取信号中产生振幅和高频损耗。 用于压差补偿的系统包括使用基于误差信号的乘法加权因子对读取信号进行滤波的自适应滤波器。 检测器接收自适应滤波器输出并产生指示写入磁带的数据的二进制信号。 整形滤波器接收二进制信号并产生表示由写入产生的读取信号并且随后读取二进制信号而没有丢失的理想读取信号。 差分器通过从理想读取信号中减去自适应滤波器输出来确定误差信号。

公开(公告)号：US06252734B1

公开(公告)日：2001-06-26

申请号：US09526798

申请日：1994-10-13

申请人： Josephus A. H. M. Kahlman ,  Albert M. A. Rijckaert

发明人： Josephus A. H. M. Kahlman ,  Albert M. A. Rijckaert

IPC分类号： G11B5035

CPC分类号： G11B20/10046 ,  G11B5/035 ,  G11B20/10009 ,  H03J7/02

摘要： An arrangement for reproducing an electric signal from a track on a magnetic record carrier (2) includes a magnetic read head (1) for reading from the track an electric signal and for supplying the electric signal to an output, and automatic equalizer filter (5), including transconductance-capacitor filter (6). The transc-filter (6) has a tuning signal input (8). The equalizer filter (5) has a control signal input (15) and is adapted to automatically equalize the electric signal read from the track in response to a control signal supplied to its control signal input, and to supply an equalized output signal at its output (12). The tuning signal input of the transc-filter is coupled to the control signal input of the equalizer filter. The arrangement further includes a control signal generator (13,16) having an output (16) coupled to the control signal input (15) of the equalizer filter (5), the generator being adapted to generate a control signal and to supply the control signal to its output (16). The transconductance-capacitor filter (6) has a magnitude filter characteristic which increases with increasing frequencies in a frequency range below a reference frequency of the filter. The transconductance-capacitor filter is adapted to control the reference frequency in the filter characteristic in response to the control signal, so as to vary the angle of inclination of the filter curve below the reference frequency.

摘要翻译： 用于从磁记录载体（2）上的轨道再现电信号的装置包括：磁读头（1），用于从轨道读出电信号并将电信号提供给输出;以及自动均衡滤波器（5） ），包括跨导电容滤波器（6）。 转码滤波器（6）具有调谐信号输入（8）。 均衡器滤波器（5）具有控制信号输入（15）并且适于响应于提供给其控制信号输入的控制信号自动地平衡从轨道读取的电信号，并在其输出端提供均衡的输出信号 （12）。 转码滤波器的调谐信号输入耦合到均衡滤波器的控制信号输入端。 该装置还包括具有耦合到均衡器滤波器（5）的控制信号输入端（15）的输出端（16）的控制信号发生器（13,16），该发生器适于产生控制信号并提供控制信号 信号到其输出（16）。 跨导 - 电容滤波器（6）具有幅度滤波器特性，其在低于滤波器参考频率的频率范围内随着频率的增加而增加。 跨导电容滤波器适于响应于控制信号来控制滤波器特性中的参考频率，以便将滤波器曲线的倾斜角度改变到低于参考频率。

公开(公告)号：US06198587B1

公开(公告)日：2001-03-06

申请号：US08680985

申请日：1996-07-16

申请人： Hideki Hayashi

发明人： Hideki Hayashi

IPC分类号： G11B5035

CPC分类号： G11B20/10009 ,  G11B7/005 ,  G11B19/12

摘要： A recording information reproducing apparatus which can precisely reproduce a digital signal from any one of a plurality of kinds of recording disks of different recording densities. A recording density of a recording medium as a reproduction target is detected and an amplitude of a high frequency component of a read signal read out from the recording medium is increased by a gain according to the detected recording density.

摘要翻译： 一种可以从不同记录密度的多种记录盘中的任何一种精确再现数字信号的记录信息再现装置。 检测作为再现目标的记录介质的记录密度，并且根据检测到的记录密度增加从记录介质读出的读取信号的高频分量的幅度增加增益。

公开(公告)号：US06819514B1

公开(公告)日：2004-11-16

申请号：US08640351

申请日：1996-04-30

申请人： Richard T. Behrens ,  Li Du ,  William G. Bliss ,  David E. Reed ,  Mark S. Spurbeck

发明人： Richard T. Behrens ,  Li Du ,  William G. Bliss ,  David E. Reed ,  Mark S. Spurbeck

IPC分类号： G11B5035

CPC分类号： G11B20/10194 ,  G11B20/10037 ,  G11B20/10055 ,  G11B20/1258 ,  G11B20/1876

摘要： A sampled amplitude read channel for magnetic disk recording which asynchronously samples the analog read signal, adaptively equalizes the resulting discrete time sample values according to a target partial response, extracts synchronous sample values through interpolated timing recovery, and detects digital data from the synchronous sample values using a Viterbi sequence detector is disclosed. To minimize interference from the timing and gain control loops, the phase and magnitude response of the adaptive equalizer filter are constrained at a predetermined frequency using an optimal orthogonal projection operation as a modification to a least mean square (LMS) adaptation algorithm. Further, with interpolated timing recovery, the equalizer filter and its associated latency are removed from the timing recovery loop, thereby allowing a higher order discrete time filter and a lower order analog filter.

摘要翻译： 用于磁盘记录的采样幅度读取通道，其异步采样模拟读取信号，根据目标部分响应对所得离散时间采样值进行自适应均衡，通过内插定时恢复提取同步采样值，并从同步采样值检测数字数据 公开了使用维特比序列检测器。 为了最小化来自定时和增益控制环路的干扰，使用最佳正交投影操作将自适应均衡器滤波器的相位和幅度响应约束在预定频率，作为对最小均方（LMS）适配算法的修改。 此外，通过内插定时恢复，均衡器滤波器及其相关等待时间从定时恢复环路中移除，从而允许较高阶离散时间滤波器和较低阶模拟滤波器。

公开(公告)号：US06496316B1

公开(公告)日：2002-12-17

申请号：US09721988

申请日：2000-11-27

申请人： Yosuke Hori ,  Yasuhide Ouchi ,  Naoki Satoh

发明人： Yosuke Hori ,  Yasuhide Ouchi ,  Naoki Satoh

IPC分类号： G11B5035

CPC分类号： G11B20/182 ,  G11B5/02 ,  G11B5/09 ,  G11B20/10009 ,  G11B20/10194 ,  G11B20/1833

摘要： A magnetic recording and reproduction apparatus, includes a circuit for changing a reference amplitude value of a Viterbi detector. The circuit is used to record and reproduce data with the reference amplitude value displaced from a reference value, thereby measuring the data error rate. Displacement of the reference amplitude from a reference value increases the data error rate, and therefore the data error rate can be measured within a short time. A data error rate with the reference amplitude equal to a reference value is estimated from the data error rate measurement, thereby making it possible to evaluate the degree of accuracy of a magnetic recording and reproduction apparatus. The data error rate is measured with the reference amplitude of the Viterbi detector displaced from a reference value while changing the equalization coefficient value of a waveform equalizer, the cut-off frequency of a low-pass filter and the write precompensation amount of a write precompensation circuit. In this way, the effect of the reproduction channel parameter or the write precompensation amount on the degree of accuracy of the magnetic recording and reproduction apparatus is evaluated, and the optimum value of the reproduction channel parameter or the write precompensation amount can thus be determined.

摘要翻译： 磁记录和再现装置包括用于改变维特比检测器的参考幅度值的电路。 该电路用于记录和再现参考振幅值从参考值偏移的数据，从而测量数据错误率。 参考幅度从参考值的位移增加了数据错误率，因此可以在短时间内测量数据错误率。 从数据误差率测量来估计参考幅度等于参考值的数据错误率，从而可以评估磁记录和再现装置的精度。 在改变波形均衡器的均衡系数值，低通滤波器的截止频率和写入预补偿的写入预补偿量的同时，维特比检测器的参考幅度从参考值偏移来测量数据错误率 电路。 以这种方式，评估再现频道参数或写入预补偿量对磁记录和再现装置的精度的影响，从而可以确定再现频道参数的最佳值或写入预补偿量。

公开(公告)号：US06378107B1

公开(公告)日：2002-04-23

申请号：US09339748

申请日：1999-06-24

申请人： Tadaaki Yoshinaka

发明人： Tadaaki Yoshinaka

IPC分类号： G11B5035

CPC分类号： G11B20/10055 ,  G11B20/10009 ,  G11B20/10296 ,  H03M13/3961 ,  H03M13/41 ,  H03M13/4107 ,  H03M13/6331 ,  H03M13/6343

摘要： This invention relates to a digital signal reproducing apparatus. This invention is applicable to an apparatus such as a video tape recorder and an optical disk drive, using a Viterbi decoder therein. Noise characteristics are equalized at points of discrimination by adding an equalized signal SPR4 of a differential system and an equalized signal SPR1 of an integrating system in a weighted manner, or by adding up metrics Maa-Mbb, (Ma′, Mb′) relative to amplitude reference values calculated for the two equalized signals SPR4 and SPR1, over each of relevant paths in a weighted fashion. The arrangements allow the inventive apparatus to avert noise-induced deterioration of discrimination accuracy.

摘要翻译： 本发明涉及数字信号再生装置。 本发明可应用于诸如录像机和光盘驱动器的装置，其中使用维特比解码器。 通过以加权方式加入差分系统的均衡信号SPR4和积分系统的均衡信号SPR1，或者通过将相关度为Maa-Mbb（Ma'，Mb'）的相加值相加 对于两个均衡信号SPR4和SPR1计算的振幅参考值，以加权方式在每个相关路径上。 该装置允许本发明的装置避免噪声引起的辨别精度的恶化。

公开(公告)号：US06285520B1

公开(公告)日：2001-09-04

申请号：US09317609

申请日：1999-05-25

申请人： Tetsuya Makiura ,  Reijiro Tsuchiya

发明人： Tetsuya Makiura ,  Reijiro Tsuchiya

IPC分类号： G11B5035

CPC分类号： G11B19/04 ,  G11B5/012 ,  G11B5/035 ,  G11B20/10009 ,  G11B20/1816

摘要： In a magnetic disk device, a deterioration of performance caused by an environmental variation is suppressed by utilizing an automatic adaptation function in a read/write channel IC. A gate provides a timing for the automatic adaptation of an equalization coefficient, a signal from the gate is given to a read-gate input terminal of the read/write channel IC, and the gate for the automatic adaptation is opened before reading data from a destination sector to be read. The automatic adaptation is started, whereby coefficients for equalization are adapted to signal wave forms before reading data.

摘要翻译： 在磁盘装置中，通过利用读/写通道IC中的自动适应功能来抑制由环境变化引起的性能的劣化。 门提供用于均衡系数的自动调整的定时，来自门的信号被提供给读/写通道IC的读门输入端，并且用于自动适配的门在从 目的地扇区被读取。 开始自动适应，由此用于均衡的系数适于在读取数据之前对波形进行信号。

公开(公告)号：US06222694B1

公开(公告)日：2001-04-24

申请号：US08736602

申请日：1996-10-24

申请人： Yoshiyuki Sasaki

发明人： Yoshiyuki Sasaki

IPC分类号： G11B5035

CPC分类号： G11B5/00813 ,  G11B5/09 ,  G11B20/10009 ,  G11B20/18

摘要： A reproduction apparatus for reproducing data, from a magnetic recording medium on which digital data is recorded, using a magnetic head, which includes a head amplifier which amplifies a reproduced signal obtained from the magnetic head, and has controllable resonance characteristics at least with respect to the magnetic head; an error correction decoding circuit for performing error correction by performing error detection of the reproduced signal obtained from the head amplifier; and a head amplifier control circuit for controlling the resonance characteristics of the head amplifier on the basis of an error detection signal obtained from the error correction decoding circuit.

摘要翻译： 一种用于使用磁头从其上记录有数字数据的磁记录介质再现数据的再现装置，该磁头包括放大从磁头获得的再现信号的头放大器，并且至少相对于 磁头; 纠错解码电路，用于通过对从头放大器获得的再现信号进行错误检测来执行纠错; 以及头放大器控制电路，用于根据从纠错解码电路获得的误差检测信号来控制前置放大器的谐振特性。