公开(公告)号：US5090005A

公开(公告)日：1992-02-18

申请号：US428937

申请日：1989-10-30

申请人： Fumio Hara ,  Seiichi Mita ,  Morishi Izumita ,  Hiroyuki Tsuchinaga

发明人： Fumio Hara ,  Seiichi Mita ,  Morishi Izumita ,  Hiroyuki Tsuchinaga

IPC分类号： G11B7/00 ,  G11B7/003 ,  G11B7/0055 ,  G11B7/09

CPC分类号： G11B7/09 ,  G11B7/0031

摘要： A tape recorder of the present invention comprises a pair of feed and take-up spools for winding a tape as recording media, a rotatable drum rotated to wind and run the tape between the pair of spools over the drum surface helically, a head for recording, reproducing or erasing signals on the tape wound over said drum surface, and control means for controlling the relative positional relationship between the head and the tape wound over the drum surface based on an error signal such that said signals are stably recorded, reproduced or erased along a desired track, the control means having means for holding the error signal during the period in which the tape is discontinued over a drum surface. The value of the error signal at the time immediately before the tape disappears from the drum surface, or the value of the error signal at the time immediately after the tape reappears over the drum surface during the preceding rotation of the drum is used as the error signal to be held, thereby allowing to stably restart the positioning control when the tape reappears over the drum surface.

摘要翻译： 本发明的磁带录音机包括一对用于卷绕磁带作为记录介质的进给卷轴和卷取卷轴，旋转的滚筒旋转以在螺旋状的卷筒表面上的一对卷轴之间卷绕和运行磁带，用于记录的磁头 ，再现或擦除在所述鼓表面上缠绕的磁带上的信号;以及控制装置，用于基于误差信号控制磁头和缠绕在磁鼓表面上的磁带之间的相对位置关系，使得所述信号被稳定地记录，再现或擦除 所述控制装置具有用于在所述磁带在鼓表面上停止的时段期间保持所述误差信号的装置。 在磁带从磁鼓表面消失之前的时刻的误差信号的值，或在磁带的前一个旋转期间磁带重新出现在磁鼓表面之后的时刻的误差信号的值被用作误差 信号被保持，从而当带重新出现在滚筒表面上时，允许稳定地重新启动定位控制。

公开(公告)号：US06373407B1

公开(公告)日：2002-04-16

申请号：US09255733

申请日：1999-02-23

申请人： Takushi Nishiya ,  Tatsuya Hirai ,  Seiichi Mita ,  Takashi Nara ,  Yoichi Uehara ,  Hiroshi Ide ,  Kyoko Tsukano ,  Yoshiju Watanabe

发明人： Takushi Nishiya ,  Tatsuya Hirai ,  Seiichi Mita ,  Takashi Nara ,  Yoichi Uehara ,  Hiroshi Ide ,  Kyoko Tsukano ,  Yoshiju Watanabe

IPC分类号： H03M700

CPC分类号： H03M5/145 ,  G11B20/1426 ,  G11B2020/1446

摘要： The computer system includes a host system, a recording medium, and a digital signal decoder connected to the host system and the recording medium. The digital signal decoder receives M-bit data and generates an N-bit code word from the M-bit data. The number of consecutive bits of 1 in the code word is not larger than a first predetermined number K, and the number of consecutive bits of 0 is not larger than a second predetermined number L. When data is recorded/reproduced by a method such as NRZI (Non-Return to Zero Inverted), or the like, there is a defect in that the number of transitions of data is larger in a code with a high data encoding rate, and the run length of zero is long thereby increasing the data decoding error rate with the recording/reproducing of data. In the digital signal decoder according to the present invention, any code word includes at most 3 consecutive bits of 1, and at most 11 consecutive bits of 0, so that the data decoding error rate can be reduced.

摘要翻译： 计算机系统包括主机系统，记录介质和连接到主机系统和记录介质的数字信号解码器。 数字信号解码器接收M位数据并从M位数据生成N位代码字。 代码字中的连续比特数1不大于第一预定数K，连续比特数0不大于第二预定数L.当通过诸如以下方法记录/再现数据时 NRZI（不归零归零）等，存在数据的转换次数较大的缺点，数据编码速率高的代码，零的行程长，从而增加数据 解码错误率与数据的记录/再现。 在根据本发明的数字信号解码器中，任何代码字包括最多3个连续位1和至多11个连续位0，从而可以减少数据解码错误率。

公开(公告)号：US5151924A

公开(公告)日：1992-09-29

申请号：US454406

申请日：1989-12-21

申请人： Seiichi Mita ,  Morishi Izumita ,  Hiroshi Ide ,  Nobukazu Doi ,  Yoshinori Okada ,  Yasuo Inagaki

发明人： Seiichi Mita ,  Morishi Izumita ,  Hiroshi Ide ,  Nobukazu Doi ,  Yoshinori Okada ,  Yasuo Inagaki

IPC分类号： G11B5/09 ,  G11B20/10 ,  H03H15/00 ,  H04B3/06 ,  H04L25/03 ,  H04N5/926 ,  H04N5/93

CPC分类号： H04L25/03038 ,  G11B20/10009 ,  H04N5/926 ,  H04N5/93

摘要： An automatic equalization apparatus useful for supplying an output signal of a transversal filter simultaneously to two juxtaposed comparators, one of the two comparators performing signal identification, the other of the two comparators detecting an equalization error with the reference level changed, and extracting data from resultant two kinds of data trains by taking at least (N-1)/2+1 bits as the unit, N being the number of taps of the transversal filter, performing correlation computation, and setting tap coefficients of the transversal filter on the basis of the resultant accumulated value.

摘要翻译： 一种自动均衡装置，用于同时向两个并置的比较器提供横向滤波器的输出信号，两个比较器之一执行信号识别，两个比较器中的另一个比较器检测参考电平改变的均衡误差，并从结果中提取数据 通过以至少（N-1）/ 2 + 1位为单位，N为横向滤波器的抽头数，执行相关计算，以及基于横向滤波器的抽头系数设置两种数据串 产生累计值。

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。

公开(公告)号：US06731441B2

公开(公告)日：2004-05-04

申请号：US10214599

申请日：2002-08-09

申请人： Hideaki Maeda ,  Morishi Izumita ,  Terumi Takashi ,  Seiichi Mita

发明人： Hideaki Maeda ,  Morishi Izumita ,  Terumi Takashi ,  Seiichi Mita

IPC分类号： G11B2006

CPC分类号： G11B20/1403 ,  G11B20/10009

摘要： Here is disclosed an information recording and reproducing apparatus comprising a multi-phase quadrature angular modulator for subjecting a signal to be written on a recording medium to multi-phase quadrature angular modulation to generate a modulated signal expressing information in phase difference and frequency difference, a quantizer for generating a discrete signal by making discrete the amplitude of the modulated signal generated by the quadrature angular modulator with reference to a certain level, a write head for writing the output signal of the quantizer onto the recording medium, a read head for reading information written on the recording medium, a read compensate circuit for compensating the phase and amplitude of a signal readout of the read head, and a multi-phase quadrature angular demodulator for demodulating a signal supplied from the read compensate circuit by subjecting it to multi-phase quadrature angular demodulation. By expressing information to be recorded in phase difference or frequency difference, it is made possible to record or reproduce the information at the varying timing of amplitude, and the bit inversion interval can be controlled by regulating the timing of amplitude variation.

摘要翻译： 这里公开了一种信息记录和再现装置，包括一个多相正交角度调制器，用于使信号被写入记录介质以进行多相正交角度调制以产生表示相位差和频差的信息的调制信号， 量化器，用于通过使由正交角调制器产生的调制信号的幅度相对于一定电平离散来产生离散信号，用于将量化器的输出信号写入记录介质的写入头，用于读取信息的读取头 写在记录介质上的读取补偿电路，用于补偿读取头的信号读出的相位和幅度的读取补偿电路;以及多相正交角解调器，用于对从读取的补偿电路提供的信号进行多相 正交角解调。 通过表示要以相位差或频率差记录的信息，可以在变化的幅度定时记录或再现信息，并且可以通过调节幅度变化的定时来控制位反转间隔。

公开(公告)号：US06493165B1

公开(公告)日：2002-12-10

申请号：US09406920

申请日：1999-09-28

申请人： Naoki Satoh ,  Seiichi Mita

发明人： Naoki Satoh ,  Seiichi Mita

IPC分类号： G11B5035

CPC分类号： G11B20/10009 ,  G11B5/012 ,  G11B5/035 ,  G11B5/09 ,  G11B20/18 ,  G11B2020/183

摘要： There is provided a magnetic disk drive in which the adaptability of read signal processing of the magnetic disk drive is enhanced so that the frequency of retry or miscorrection in use is reduced. This magnetic disk drive has a read circuit, and a channel condition measuring circuit. An output of an A/D converter contained in the read circuit is supplied to a digital equalizing circuit so as to be equalized accurately. Upon input of a signal for instructing a coefficient learning circuit to learn the coefficient of the digital equalizing circuit, the initial coefficient registered in a register is set as a coefficient value in another register and the coefficient learning circuit is operated to start consecutive learning of coefficient values. In the channel condition measuring circuit, errors in a row of output values of the digital equalizing circuit are calculated and an integrated value of squares of the errors is compared with an error threshold value. If the integrated value is larger than the error threshold value, coefficient learning is regarded as being abnormal and a control signal for discarding the coefficient registered in the register is issued so that the register is reset to the initial coefficient value. The signal for instructing the coefficient learning circuit to learn the coefficient may be outputted in a sector previous to the read target sector or may be outputted in the read target sector.

摘要翻译： 提供了一种磁盘驱动器，其中增强了磁盘驱动器的读取信号处理的适应性，从而减少了使用中的重试或错误修复的频率。 该磁盘驱动器具有读取电路和通道状态测量电路。 包含在读取电路中的A / D转换器的输出被提供给数字均衡电路，以便被精确地均衡。 在输入用于指示系数学习电路以学习数字均衡电路的系数的信号时，登记在寄存器中的初始系数被设置为另一寄存器中的系数值，并且系数学习电路被操作以开始系数的连续学习 价值观。 在通道条件测量电路中，计算数字均衡电路的一行输出值的误差，并将误差的平方的积分值与误差阈值进行比较。 如果积分值大于误差阈值，则将系数学习视为异常，并且发出用于丢弃寄存在寄存器中的系数的控制信号，使得寄存器被重置为初始系数值。 用于指示系数学习电路学习系数的信号可以在读取目标扇区之前的扇区中输出，或者可以在读取的目标扇区中输出。

公开(公告)号：US06320916B1

公开(公告)日：2001-11-20

申请号：US09185097

申请日：1998-11-03

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

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

IPC分类号： H03D100

CPC分类号： H03M13/6331 ,  G11B20/10 ,  G11B20/18 ,  H03M13/09 ,  H03M13/41 ,  H03M13/4115 ,  H03M13/4184 ,  H03M13/6343 ,  H03M13/6502 ,  H03M13/6505 ,  H04L25/03178

摘要： A digital magnetic recording/reproducing apparatus that has an LVA detector, and that is able to maintain the coding rate as high as {fraction (8/9)} or more, and record at a higher density than in the prior art, wherein, in order that the data sequences up to the (2n−1)th best sequence (n>1) are obtained in the order of higher likelihood ratios, and that. the candidates of those data sequences can be produced, the LVA detector has provided therein a unit which replaces the likelihood ratio and path memory of the ith best sequence by those of the (2i−1)th best sequence when the contents of the (i−1)th path memory coincide with those of the ith path memory (i=2, 3, . . . , n) and the absolute value of the likelihood ratio difference between the (i−1)th best sequence and the (2i−1)th best sequence is smaller than a decision threshold, or a unit which initializes the likelihood ratio of the ith best sequence to be a constant difference value added to the likelihood ratio of the (i−1)th best sequence when the contents of the (i−1)th path memory and the ith (i=2, 3, . . . , n) path memory of the n candidates of data sequences are coincident.

摘要翻译： 具有LVA检测器的数字磁记录/再现装置，其能够将编码率保持为高达{分数（8/9）}或更大，并且以比现有技术更高的密度进行记录，其中， 为了获得高达（2n-1）个最佳序列（n> 1）的数据序列是以较高似然比的顺序获得的。 可以产生这些数据序列的候选，LVA检测器在其中提供了一个单元，其当第（i）个（i-1）的内容被替换为第（2i-1）个最佳序列时的第i个最佳序列的似然比和路径存储器 -1）路径存储器与第i路径存储器（i = 2,3，...，n）的路径存储器一致，并且第（i-1）个最佳序列与（2i）的最佳序列之间的似然比差的绝对值 -1）的最佳序列小于判定阈值，或将第i个最佳序列的似然比初始化为当第（i-1）个最佳序列的似然比加到内容的第i-1个最佳序列的似然比时的单位， （i-1）路径存储器和n个候选数据序列的第i（i = 2,3，...，n）路径存储器是一致的。

公开(公告)号：US6144515A

公开(公告)日：2000-11-07

申请号：US229561

申请日：1999-01-13

申请人： Yasutaka Nishida ,  Seiichi Mita ,  Naoki Satoh ,  Yoshiju Watanabe

发明人： Yasutaka Nishida ,  Seiichi Mita ,  Naoki Satoh ,  Yoshiju Watanabe

IPC分类号： G11B5/00 ,  G11B5/02 ,  G11B5/035 ,  G11B5/09 ,  G11B20/10 ,  H03H17/06 ,  G11B5/03

CPC分类号： G11B5/09 ,  G11B20/10009 ,  H03H17/06 ,  G11B2005/0016 ,  G11B5/012 ,  G11B5/035

摘要： The equalizer is capable of generating an equalized output that is compensated in the non-linearity of the signal reproduced by an MR head and a reliable high-density magnetically recorded-signal reproducer. The equalizer of an FIR-type filter structure includes a plurality of delay elements for delaying an input signal by a certain period, a plurality of coefficient processing units provided to input or output taps of the delay elements, and an adder for obtaining the sum of the outputs of the coefficient processing units. The distortion of the reproduced waveform can be corrected by a relatively simple circuit structure by comparing the signal value inputted to the coefficient processing unit from each tap with a predetermined threshold level and changing the signal value and a coefficient value to be multiplied in accordance with the comparison result. Therefore, any one of various existing signal processing systems can be applied to the decoding of reproduced signals of an MR head having the non-linear characteristic.

摘要翻译： 均衡器能够产生均衡的输出，该均衡输出以由MR头和可靠的高密度磁记录信号再现器再现的信号的非线性来补偿。 FIR型滤波器结构的均衡器包括用于将输入信号延迟一定周期的多个延迟元件，提供给输入或输出延迟元件的抽头的多个系数处理单元，以及用于获得 系数处理单元的输出。 通过将输入到系数处理单元的每个抽头的系数处理单元的信号值与预定的阈值电平相比较，可以通过相对简单的电路结构来校正再现波形的失真，并且根据该调整信号值改变信号值和要乘以的系数值 比较结果。 因此，各种现有信号处理系统中的任一种可以应用于具有非线性特性的MR头的再现信号的解码。

公开(公告)号：US06069856A

公开(公告)日：2000-05-30

申请号：US975670

申请日：1997-11-28

申请人： Seiichi Mita ,  Terumi Takashi ,  Naoki Satoh

发明人： Seiichi Mita ,  Terumi Takashi ,  Naoki Satoh

IPC分类号： G11B20/14 ,  G11B5/012 ,  G11B5/09 ,  G11B20/10 ,  G11B20/18 ,  G11B7/005

CPC分类号： G11B20/10009 ,  G11B5/012 ,  G11B5/09

摘要： An information recording/reproducing apparatus includes first and second data demodulators having different data discriminating capabilities. The first data demodulator has a lower data discriminating capability and the second data demodulator has a higher data discriminating capability. When the reliability of reliability information for demodulation data generated by the first data demodulator, the second data demodulator is operated so that demodulation data generated by the first data demodulator is replaced by demodulation data generated by the second data demodulator during a period of time when the reliability of the reliability information is deteriorated.

摘要翻译： 信息记录/再现装置包括具有不同数据鉴别能力的第一和第二数据解调器。 第一数据解调器具有较低的数据鉴别能力，第二数据解调器具有较高的数据识别能力。 当由第一数据解调器产生的解调数据的可靠性信息的可靠性操作时，第二数据解调器被操作，使得由第一数据解调器产生的解调数据被第二数据解调器产生的解调数据替换为在第 可靠性信息的可靠性恶化。

公开(公告)号：US5774470A

公开(公告)日：1998-06-30

申请号：US524040

申请日：1995-09-06

申请人： Takushi Nishiya ,  Shoichi Miyazawa ,  Kazutoshi Ashikawa ,  Ryushi Shimokawa ,  Seiichi Mita

发明人： Takushi Nishiya ,  Shoichi Miyazawa ,  Kazutoshi Ashikawa ,  Ryushi Shimokawa ,  Seiichi Mita

IPC分类号： G06F11/10 ,  G11B20/10 ,  G11B20/18 ,  H03H15/00 ,  H03H17/00 ,  H03H21/00 ,  H03M13/23 ,  H03M13/41 ,  H04B3/04

CPC分类号： G11B20/10055 ,  G11B20/10009 ,  G11B20/18 ,  H03M13/41 ,  H03M13/6331 ,  H03M13/6505

摘要： A playback signal processing circuit for reducing decode errors and enabling high-density digital magnetic recording and a digital magnetic recording reproducing unit using the playback signal processing circuit are provided. An estimated waveform generation circuit uses the decoding result of a PRML channel to generate an ideal playback signal waveform. A subtractor provides a waveform representing a difference between the waveform and an actual playback signal. There is a high probability that error bits will occur at an interval of two or four bits because of the nature of GCR code and maximum-likelihood decoding; in the error state of each bit, one bit is incremented by one with respect to the correct bit value and the other signal bit is decremented by one. From this fact, an error detection circuit discriminates an error difference waveform pattern and an error discrimination circuit detects an error bit interval, whereby an error correction circuit carries out error bit correction.

摘要翻译： 提供了一种用于减少解码错误并实现高密度数字磁记录的重放信号处理电路和使用重放信号处理电路的数字磁记录再现单元。 估计波形生成电路使用PRML通道的解码结果来产生理想的重放信号波形。 减法器提供表示波形和实际重放信号之间的差异的波形。 由于GCR码的性质和最大似然解码，错误位将以两位或四位的间隔发生的概率很高; 在每个位的错误状态下，一个比特相对于正确的比特值递增1，另一个比特递减1。 根据该事实，误差检测电路鉴别误差波形图案，误差鉴别电路检测误差位间隔，由此误差校正电路进行错误位校正。