公开(公告)号：US5594756A

公开(公告)日：1997-01-14

申请号：US492616

申请日：1995-06-20

申请人： Wataru Sakurai ,  Hideki Sawaguchi ,  Naoki Satoh ,  Masuo Umemoto

发明人： Wataru Sakurai ,  Hideki Sawaguchi ,  Naoki Satoh ,  Masuo Umemoto

IPC分类号： G11B20/10 ,  H04B1/10 ,  H04B3/06 ,  H04B3/08 ,  H04L25/03 ,  H03H7/30

CPC分类号： H04L25/03057 ,  G11B20/10009 ,  G11B20/10046

摘要： A decision feedback equalization circuit which can be operated at a high speed with a low cost as well as a high-speed digital data communication system and a high-speed digital data recording system using the equalization circuit are disclosed. The decision feedback equalization circuit has data memories which correspond to the number of available values in decision result and in which feedback signals corresponding to all the next decision results are previously prepared as candidates so that a suitable one of the feedback signal candidates is selected and fed back based on the obtained decision result, thus realizing high-speed operation of a feedback loop.

摘要翻译： 公开了一种能够以低成本高速运行的判决反馈均衡电路以及使用均衡电路的高速数字数据通信系统和高速数字数据记录系统。 判决反馈均衡电路具有数据存储器，其对应于判定结果中可用值的数量，并且其中预先对应于所有下一个判定结果的反馈信号作为候选，使得选择并馈送合适的一个反馈信号候选 基于获得的决策结果，从而实现反馈回路的高速运行。

公开(公告)号：US5881071A

公开(公告)日：1999-03-09

申请号：US812286

申请日：1997-03-06

申请人： Alexander Kuznetsov ,  Masuo Umemoto ,  Naoya Kobayashi ,  Hideki Sawaguchi

发明人： Alexander Kuznetsov ,  Masuo Umemoto ,  Naoya Kobayashi ,  Hideki Sawaguchi

IPC分类号： G11B5/09 ,  G11B20/10 ,  G11B20/14 ,  G11B20/18 ,  H03M13/25 ,  G06F11/00

CPC分类号： G11B20/10009 ,  G11B20/1833

摘要： A digital write-and-read method and a signal processing apparatus wherein a write encoder includes a bit distribution circuit for dividing an input data block into n (n: 2 or more) series of bit strings and outputting them in parallel, a first coding circuit for executing predetermined coding for each of data series so distributed and a second coding circuit for converting the output bit series D1 to D3 of the first coding circuit to an n-bit channel code by looking up the previous channel code information, and wherein the second coding circuit executes coding by using a combination having a large Euclidean distance in a partial response equalization output taking inter-symbol interference of at least three bits into consideration as a pair.

摘要翻译： 一种数字写入读取方法和信号处理装置，其中写入编码器包括一个位分配电路，用于将输入数据块分成n（n：2或更多）个位串并将它们并行输出;第一编码 用于对分配的数据序列中的每一个执行预定编码的电路和用于通过查找先前的信道码信息将第一编码电路的输出比特串D1至D3转换为n比特信道码的第二编码电路，并且其中， 第二编码电路在部分响应均衡输出中使用具有较大欧几里德距离的组合来执行编码，以至少考虑三比特的符号间干扰作为一对。

公开(公告)号：US5519398A

公开(公告)日：1996-05-21

申请号：US135478

申请日：1993-10-13

申请人： Naoki Satoh ,  Hirotsugu Kojima ,  Hideki Sawaguchi ,  Masao Hotta

发明人： Naoki Satoh ,  Hirotsugu Kojima ,  Hideki Sawaguchi ,  Masao Hotta

IPC分类号： G11B5/09 ,  H03H17/02 ,  H03H17/06 ,  H03M1/06 ,  H03M1/12 ,  H03M1/14 ,  H03M1/16 ,  H03M1/36

CPC分类号： H03M1/0626 ,  H03M1/148 ,  H03M1/168 ,  H03M1/365

摘要： A signal processing apparatus for converting an analog signal to a digital signal and processing the digital signal. In particular, a digital filter for performing processing at high speed is implemented by using an integrated circuit of low power consumption. The signal processing apparatus includes a circuit for comparing an input analog signal with each voltage of a plurality of analog reference voltages and generating a thermometer code Tc depending upon the analog input signal, a decoder for detecting a change point of the thermometer code Tc, and a plurality of memory circuits having output signal lines of the decoder as word selection lines. The product of an input signal value corresponding to each word selection line and a predetermined filter coefficient is stored in the corresponding word of the memory circuits. The memories are used as look-up tables.

摘要翻译： 一种用于将模拟信号转换为数字信号并处理数字信号的信号处理装置。 特别地，通过使用低功耗的集成电路来实现用于高速执行处理的数字滤波器。 该信号处理装置包括用于将输入模拟信号与多个模拟参考电压的每个电压进行比较并根据模拟输入信号产生温度计代码Tc的电路，用于检测温度计代码Tc的变化点的解码器，以及 具有解码器的输出信号线作为字选择线的多个存储电路。 对应于每个字选择行的输入信号值与预定的滤波器系数的乘积存储在存储器电路的相应字中。 这些记忆被用作查找表。

公开(公告)号：US20110013306A1

公开(公告)日：2011-01-20

申请号：US12923307

申请日：2010-09-14

申请人： Hideki Sawaguchi ,  Yasutaka Nishida ,  Hisashi Takano ,  Hiroyuki Tsuchinaga

发明人： Hideki Sawaguchi ,  Yasutaka Nishida ,  Hisashi Takano ,  Hiroyuki Tsuchinaga

IPC分类号： G11B5/09

CPC分类号： G11B20/10009 ,  G11B5/09 ,  G11B20/10203 ,  G11B2005/0016 ,  G11B2005/0029

摘要： To effectively suppress a signal in a low frequency region in which the medium noise and the signal distortion are concentrated, and in order to effectively utilize a detected component of the reproduced signal in the low frequency region, a target of partial response equalization to the perpendicularly recorded/reproduced signal is set so that the low-frequency component around the direct current is suppressed to a regulated quantity for both the effective suppression and the effective utilization. Accordingly, a maximum-likelihood decoding process is carried out through the target of partial response equalization. Reliability of data detection is made higher and a signal-to-noise ratio is improved, so that the noise from the recording medium can be reduced more and it is possible to provide a high-density magnetic recording/reproducing apparatus.

摘要翻译： 为了有效地抑制中等噪声和信号失真集中的低频区域中的信号，为了有效地利用低频区域中的再现信号的检测分量，将垂直方向的部分响应均衡的目标 记录再现信号被设定为使得直流电流周围的低频分量被抑制到有效抑制和有效利用两者的规定量。 因此，通过部分响应均衡的目标来执行最大似然解码处理。 数据检测的可靠性进一步提高，信噪比得到改善，从而可以进一步降低来自记录介质的噪声，并且可以提供高密度的磁记录/重放装置。

公开(公告)号：US07443625B2

公开(公告)日：2008-10-28

申请号：US11404780

申请日：2006-04-17

申请人： Takehiko Hamaguchi ,  Atsushi Nakamura ,  Yasutaka Nishida ,  Hisashi Takano ,  Yohji Maruyama ,  Hiroshi Ide ,  Hideki Sawaguchi ,  Futoshi Tomiyama

发明人： Takehiko Hamaguchi ,  Atsushi Nakamura ,  Yasutaka Nishida ,  Hisashi Takano ,  Yohji Maruyama ,  Hiroshi Ide ,  Hideki Sawaguchi ,  Futoshi Tomiyama

IPC分类号： G11B5/02

CPC分类号： G11B5/012 ,  G11B5/4886 ,  G11B27/02

摘要： In the present invention, by making the width of the write element larger than the track pitch and securing a write magnetic field strong enough to reverse the magnetization of the magnetic layer, and further by writing while shifting a write head comprising the write element, a magnetic disk drive, of which the track width is narrower than the write element width, and the storage capacity is large, is realized.

摘要翻译： 在本发明中，通过使写入元件的宽度大于轨道间距，并且确保写入磁场足够强以反转磁性层的磁化，并且进一步通过在包括写入元件的写入头的移位的同时进行写入， 磁盘驱动器，其轨道宽度比写入元件宽度窄，并且存储容量大。

公开(公告)号：US07092181B2

公开(公告)日：2006-08-15

申请号：US11196385

申请日：2005-08-04

申请人： Yasutaka Nishida ,  Takehiko Hamaguchi ,  Hideki Sawaguchi

发明人： Yasutaka Nishida ,  Takehiko Hamaguchi ,  Hideki Sawaguchi

IPC分类号： G11B5/09

CPC分类号： G11B20/10046 ,  G11B5/012 ,  G11B5/09 ,  G11B5/59633 ,  G11B20/10009 ,  G11B20/10481 ,  G11B27/3027 ,  G11B2005/0029 ,  G11B2220/20

摘要： A method of enhancing the thermal stability of gray codes is disclosed. The gray code block in a servo area is recorded with a combination of two different magnetization directions. When the two different magnetization directions are expressed as “+” and “−”, the information “1” is recorded as “++−−” or “−−++” with the information “0” recorded as “+−+−” or “−+−+”. Since the filter for gray code demodulation is provided with a perpendicular recording mode, the servo area does not use long-wavelength signals that are susceptible to thermal demagnetization. As a result, thermal stability is enhanced.

公开(公告)号：US07027248B2

公开(公告)日：2006-04-11

申请号：US10633621

申请日：2003-08-05

申请人： Takehiko Hamaguchi ,  Atsushi Nakamura ,  Yasutaka Nishida ,  Masafumi Mochizuki ,  Hideki Sawaguchi

发明人： Takehiko Hamaguchi ,  Atsushi Nakamura ,  Yasutaka Nishida ,  Masafumi Mochizuki ,  Hideki Sawaguchi

IPC分类号： G11B5/02

CPC分类号： G11B5/6005 ,  G11B5/012 ,  G11B5/105 ,  G11B5/127 ,  G11B5/1272 ,  G11B5/2654 ,  G11B5/4886 ,  G11B5/56 ,  G11B2005/001 ,  G11B2005/0021

摘要： In a thermal assisted type magnetic disk apparatus having a head holding a heat element and a write element, in which coercivity of a disk is locally reduced by temperature-increasing the disk and writing is performed by the write element, along with a seek operation to move the head by a rotary actuator in a radial direction, a yaw angle is changed and a heat area and the write element are track-shifted. A mechanism to offset one of the heat area and the write element in a width direction of a slider, to array the heat element and the write element in a track running direction in correspondence with the yaw angle of the head.

摘要翻译： 在具有保持加热元件的头部和写入元件的热辅助型磁盘装置中，通过写入元件，通过写入元件执行盘的矫顽力局部减小并且进行寻道操作 通过旋转致动器在径向方向上移动头部，改变偏航角，并且对热区域和写入元件进行轨道移动。 一种抵消滑块的宽度方向上的加热区域和写入元件中的一个的机构，用于使加热元件和写入元件沿与磁头的偏航角相对应的磁道行进方向排列。

公开(公告)号：US06657805B2

公开(公告)日：2003-12-02

申请号：US09944205

申请日：2001-09-04

申请人： Yasutaka Nishida ,  Takehiko Hamaguchi ,  Hisashi Takano ,  Hiroshi Ide ,  Hideki Sawaguchi ,  Futoshi Tomiyama

发明人： Yasutaka Nishida ,  Takehiko Hamaguchi ,  Hisashi Takano ,  Hiroshi Ide ,  Hideki Sawaguchi ,  Futoshi Tomiyama

IPC分类号： G11B1504

CPC分类号： G11B19/04 ,  G11B5/596

摘要： When the amount of position error PE of a magnetic head meets the condition of Ewf>PE>=Eww for two threshold values Ewf and Eww meeting Ewf>Eww, the track is registered in the track information table as a track requiring rewrite and the tracks on both sides neighboring to the track are temporarily write-inhibited. The data of the track is rewritten on another track later so as to maintain the data. By doing this, the offtrack of the recording track can be made smaller without sacrifice of the access speed and the occurrence probability of write fault can be reduced. Furthermore, the reliability of a magnetic disk apparatus can be improved.

公开(公告)号：US06337889B1

公开(公告)日：2002-01-08

申请号：US09124840

申请日：1998-07-30

申请人： Seiichi Mita ,  Hideki Sawaguchi ,  Naoya Kobayashi ,  Masaharu Kondo

发明人： Seiichi Mita ,  Hideki Sawaguchi ,  Naoya Kobayashi ,  Masaharu Kondo

IPC分类号： H04L2706

CPC分类号： G11B20/10055 ,  G11B5/012 ,  G11B5/09 ,  G11B20/10009 ,  H04L1/0054

摘要： In a data demodulating method, predetermined input data is based upon a response characteristic of the partial response class 4. The predetermined input data is discrete-filtered to thereby produce filtered asymmetrical data. The filtered asymmetrical data is maximum-likelihood-decoded to thereby produce decoded data that is demodulated. Further, a magnetic recording/reproducing apparatus is arranged by using this data demodulating method.

摘要翻译： 在数据解调方法中，预定输入数据基于部分响应类别4的响应特性。预定输入数据被离散滤波，从而产生滤波后的非对称数据。 滤波的不对称数据是最大似然解码的，从而产生被解调的解码数据。 此外，通过使用该数据解调方法来布置磁记录/再现装置。

公开(公告)号：US20100235718A1

公开(公告)日：2010-09-16

申请号：US12787120

申请日：2010-05-25

申请人： Shaohua Yang ,  Richard Leo Galbraith ,  Ksenija Lakovic ,  Yuan Xing Lee ,  Travis Oenning ,  Jongseung Park ,  Hideki Sawaguchi ,  Bruce A. Wilson

发明人： Shaohua Yang ,  Richard Leo Galbraith ,  Ksenija Lakovic ,  Yuan Xing Lee ,  Travis Oenning ,  Jongseung Park ,  Hideki Sawaguchi ,  Bruce A. Wilson

IPC分类号： H03M13/45 ,  G06F11/10

CPC分类号： H03M13/45 ,  G11B20/1833 ,  G11B2020/1863 ,  G11B2220/2516 ,  H03M13/098 ,  H03M13/1102 ,  H03M13/1515 ,  H03M13/152 ,  H03M13/256 ,  H03M13/2906 ,  H03M13/2909 ,  H03M13/2945 ,  H03M13/2957 ,  H03M13/3784 ,  H03M13/4146 ,  H03M13/6343

摘要： Two levels of error correction decoding are performed using first and second level decoders. A composite code formed by combining an inner component code and an outer component code can be used to decode the data and correct any errors. Performing two level decoding using a composite code allows the size of the inner parity block to be reduced to a single Reed-Solomon symbol while keeping a good code rate. The first level decoder generates soft information. The soft information can indicate a most likely error event for each possible syndrome value of the inner component code. The soft information can also include error metric values for each of the most likely error events. The second level decoder generates corrected syndrome values based on the soft information using the outer component code. The most likely trellis path that corresponds to the corrected syndrome values is then selected.

摘要翻译： 使用第一和第二级解码器执行两级纠错解码。 可以使用通过组合内部组件代码和外部组件代码形成的组合代码来解码数据并纠正任何错误。 使用复合代码执行两级解码允许内部奇偶校验块的大小减少到单个Reed-Solomon符号，同时保持良好的代码率。 第一级解码器产生软信息。 软信息可以指示内部组件代码的每个可能的综合征值的最可能的错误事件。 软信息还可以包括每个最可能的错误事件的误差度量值。 第二级解码器使用外部分量代码基于软信息生成校正的校正子值。 然后选择对应于校正的综合征值的最可能的网格路径。