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。

公开(公告)号：US07545595B2

公开(公告)日：2009-06-09

申请号：US11354912

申请日：2006-02-16

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： A magnetic disk apparatus including: a disk holding data as magnetic information on a magnetic recording film; a head to perform writing and reading of the magnetic information; a rotary actuator to move the head in a radial direction of the disk; plural heat elements in the head to locally heat the disk; a write element in the head to apply a magnetic field to the disk; and means for selecting at least one heat element from the plural heat elements, wherein the means for selecting the heat element selects at least one heat element from the plural heat elements so as to bring a center line of an area heated by the heat element and a center line of the position of the magnetic field generated by the write element into approximate correspondence, in correspondence with a relative angle between the head and a direction of movement of the disk.

摘要翻译： 一种磁盘装置，包括：磁盘，其将数据作为磁性信息保存在磁记录膜上; 执行写入和读取磁信息的头部; 旋转致动器，用于沿着盘的径向方向移动头部; 头部中的多个热元件以局部加热盘; 磁头中的一个写元件将磁场施加到磁盘上; 以及用于从所述多个加热元件中选择至少一个加热元件的装置，其中用于选择所述加热元件的装置从所述多个加热元件中选择至少一个加热元件，以使得由所述加热元件加热的区域的中心线，以及 由写入元件产生的磁场的位置的中心线对应于磁头与磁盘的移动方向之间的相对角度相对应。

公开(公告)号：US20090021854A1

公开(公告)日：2009-01-22

申请号：US12230989

申请日：2008-09-09

申请人： Yasutaka Nishida ,  Takehiko Hamaguchi ,  Hideki Sawaguchi ,  Hisashi Takano

发明人： Yasutaka Nishida ,  Takehiko Hamaguchi ,  Hideki Sawaguchi ,  Hisashi Takano

IPC分类号： G11B5/09

CPC分类号： G11B5/59655 ,  G11B5/59688

摘要： In a method of servo writing of a magnetic recording system and the magnetic recording system, the signal is recorded in a dummy area with a higher recording density than the burst signal. Also, the maximum bit length of the burst area is shortened as compared with the maximum bit length of the data area. A servo control method for perpendicular recording similar to that for longitudinal recording can be used to reduce the development cost. The anti-signal decay performance is also improved. Further, since the variations of the burst signal along the track width is suppressed, the positioning accuracy is improved. These effects combine to produce a reliable magnetic recording system of large capacity.

公开(公告)号：US07296215B2

公开(公告)日：2007-11-13

申请号：US10922227

申请日：2004-08-18

申请人： Morishi Izumita ,  Terumi Takashi ,  Hideki Sawaguchi ,  Seiichi Mita

发明人： Morishi Izumita ,  Terumi Takashi ,  Hideki Sawaguchi ,  Seiichi Mita

IPC分类号： H03M13/03

CPC分类号： H03M13/29 ,  G11B20/10009 ,  H03M13/1111 ,  H03M13/1191 ,  H03M13/1515 ,  H03M13/2703 ,  H03M13/3746 ,  H03M13/45 ,  H03M13/6343 ,  H03M13/6505

摘要： In one embodiment, a symbol error correction encoder effects block interleaving on recording data and thereafter performs first error correction encoding on the recording data. Next, a symbol error correction encoder performs encoding on the whole block. A reproducing processing circuit outputs likelihood information of respective bits. A first error correction decoder corrects a random error produced upon recording and reproduction, using the likelihood information. Since it is possible to make an improvement in performance with respect to the random error by repetitive decoding at this time, the post-correction data is returned to the reproducing processing circuit. After the completion of such repetitive processing, the data is digitized and subjected to an error correction in symbol unit by a hard determination, and outputted to a symbol error correction decoder.

摘要翻译： 在一个实施例中，符号纠错编码器对记录数据执行块交织，并且此后对记录数据执行第一纠错编码。 接下来，符号纠错编码器对整个块执行编码。 再现处理电路输出各位的似然信息。 第一纠错解码器使用似然信息校正记录和再现时产生的随机误差。 由于此时可以通过重复解码对随机误差进行性能改善，所以后校正数据返回到再生处理电路。 在完成这样的重复处理之后，数据被数字化，并通过硬判断进行符号单位的纠错，并将其输出到符号纠错解码器。