-
公开(公告)号：US5629914A
公开(公告)日：1997-05-13
申请号：US407125
申请日：1995-03-20
IPC分类号： G11B7/0037 , G11B20/10 , G11B7/00
CPC分类号： G11B20/10203 , G11B20/10037 , G11B7/00375
摘要： In a pulse width modulated read signal channel for an optical disk drive, a data-transition threshold is maintained for data detection by a threshold tracking circuit that estimates the amplitude centerline data-transition threshold from the most recent maximum and minimum values of the read signal waveform. To improve the accuracy of the response of the centerline estimator, the threshold is increased or decreased based on the phase error at each read signal transition through the data-transition threshold. In addition, defects in the optical recording media are detected, and a defect present signal is used to inhibit the transition phase error input to the centerline estimator. This prevents the estimator from moving the threshold to an incorrect stable level. In addition, the defect present signal boosts the error feedback in the centerline estimator. The estimator then more quickly follows the read signal waveform. As a result, the estimator reacquires the centerline of the waveform after the read head moves past the defect without retriggering the defect detection circuit.
-
公开(公告)号：US5502711A
公开(公告)日：1996-03-26
申请号：US407124
申请日：1995-03-20
IPC分类号： G11B7/005 , G11B11/105 , G11B20/14 , H03L7/07 , G11B7/00
CPC分类号： G11B20/1423 , H03L7/07 , G11B11/10515 , G11B7/005
摘要： A digital phase lock loop channel is provided for threshold detection of a pulse width modulated binary data stream that has negative and positive transitions defining one binary state of the data stream. A threshold-establishing and transition-detecting network receives this data stream and provides a first output of one polarity corresponding to the detection of a positive transition, a second output of an opposite polarity corresponding to the detection of a negative transition, and a time-of-arrival output corresponding to a positive and a negative transition. A first and a second digital PLL is provided, each PLL having a transition input, a time-of-arrival input, a phase-error input, a phase error output a data-valid output, and a data output. Each PLL has an internal digital phase detector network connected to receive its transition input and its time-of-arrival input, and each PLL is operable to generate the phase error output therefrom. Each PLL has an internal digital loop filter connected to receive the phase error output generated by its phase detector network, and to receive the phase error output that is generated by the other PLL. The output of the loop filter of each PLL is connected to the data-valid and data outputs of its respective PLL.
摘要翻译： 提供数字锁相环通道，用于阈值检测脉冲宽度调制二进制数据流，其具有定义数据流的一个二进制状态的负和正转换。 阈值建立和转移检测网络接收该数据流并且提供与正转移的检测相对应的一个极性的第一输出，对应于负转变检测的相反极性的第二输出， 到达输出对应于正和负转换。 提供第一和第二数字PLL，每个PLL具有转换输入，到达时间输入，相位误差输入，相位误差输出数据有效输出和数据输出。 每个PLL具有内部数字相位检测器网络，其连接以接收其转换输入及其到达时间输入，并且每个PLL可操作以从其产生相位误差输出。 每个PLL都有一个内部数字环路滤波器，用于接收相位检测器网络产生的相位误差输出，并接收由另一个PLL产生的相位误差输出。 每个PLL的环路滤波器的输出连接到其相应PLL的数据有效和数据输出。
-
公开(公告)号：US5508855A
公开(公告)日：1996-04-16
申请号：US418691
申请日：1995-04-07
CPC分类号： H04L25/062 , G11B20/10009 , G11B5/09
摘要： A method and apparatus for detecting peaks in a signal which comprises an alternating polarity waveform including a plurality of points. A selected point in the signal is designated. Thereafter, a threshold value for the selected point is established utilizing a prior threshold value associated set off with spaces with a point prior to the selected point as follows:(m(n)=t0*ax(n)+t1*m(n-1))wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point. In this manner the threshold value may be adjusted for fluctuations in amplitude of the signal. Next, the selected point is compared with the threshold value to determine whether or not the selected point is within a predetermined distance of the threshold. If the selected point is within the predetermined distance of the threshold value, a determination is made as to whether or not the selected point represents a peak in order to ascertain the presence of a logic one at the selected point, wherein digital data may be detected in a signal.
摘要翻译： 一种用于检测信号中的峰值的方法和装置，其包括包括多个点的交替极性波形。 指定信号中的选定点。 此后，利用与所选点之前的点的空间相关联的先前阈值建立所选点的阈值，如下：（m（n）= t0 * ax（n）+ t1 * m -1））其中n是点标识符，m（n）是阈值，t0是小于1的固定正常数，t1是小于1的固定正常数，ax（n）是 输入信号，m（n-1）是先前点的先前阈值。 以这种方式，可以根据信号幅度的波动调节阈值。 接下来，将所选择的点与阈值进行比较，以确定所选择的点是否在阈值的预定距离内。 如果所选择的点在阈值的预定距离之内，则确定所选择的点是否表示峰，以确定在所选择的点处存在逻辑1，其中可以检测数字数据 在一个信号。
-
公开(公告)号：US5530601A
公开(公告)日：1996-06-25
申请号：US129531
申请日：1993-09-30
CPC分类号： H04L25/062 , G11B20/10009 , G11B5/09
摘要： A method and apparatus for detecting peaks in a signal which comprises an alternating polarity waveform including a plurality of points. A selected point in the signal is designated. Thereafter, a threshold value for the selected point is established utilizing a prior threshold value associated set off with spaces with a point prior to the selected point as follows:(m(n)=t0*ax(n)+t1*m(n-1)wherein n is the point identifier, m(n) is the threshold value, t0 is a fixed positive constant less than one, t1 is a fixed positive constant less than one, ax(n) is the absolute value of the input signal, and m(n-1) is the prior threshold value for the prior point. In this manner the threshold value may be adjusted for fluctuations in amplitude of the signal. Next, the selected point is compared with the threshold value to determine whether or not the selected point is within a predetermined distance of the threshold. If the selected point is within the predetermined distance of the threshold value, a determination is made as to whether or not the selected point represents a peak in order to ascertain the presence of a logic one at the selected point, wherein digital data may be detected in a signal.
摘要翻译： 一种用于检测信号中的峰值的方法和装置，其包括包括多个点的交替极性波形。 指定信号中的选定点。 此后，利用与所选点之前的点的空间相关联的先前阈值建立所选点的阈值，如下：（m（n）= t0 * ax（n）+ t1 * m -1）其中n是点标识符，m（n）是阈值，t0是小于1的固定正常数，t1是小于1的固定正常数，ax（n）是输入的绝对值 信号，并且m（n-1）是先前点的先前阈值，以这种方式，可以根据信号幅度的波动来调整阈值。接下来，将所选择的点与阈值进行比较以确定是否 或者所选择的点不在阈值的预定距离内，如果所选择的点在阈值的预定距离内，则确定所选择的点是否表示峰，以确定是否存在 在选定点的逻辑1，其中数字数据可以 在信号中检测。
-
公开(公告)号：US08854759B2
公开(公告)日：2014-10-07
申请号：US13454935
申请日：2012-04-24
IPC分类号： G11B5/09
CPC分类号： G11B20/1833 , G11B5/00813 , G11B20/10379 , G11B2020/185 , H03M5/145 , H03M13/1111 , H03M13/13 , H03M13/2957 , H03M13/3905 , H03M13/3972 , H03M13/6325
摘要： In one embodiment, a tape drive system includes a soft detector for executing a first forward loop of a detection algorithm on a first block of signal samples during a first time interval; and logic for executing forward and reverse loops during several time intervals; and logic adapted for outputting a first decoded block of signal samples based on the executing the decoding algorithm on the first block during a sixth time interval, wherein a sum of second, third, fourth, fifth, and sixth time intervals are about equal in duration to the first time interval.
摘要翻译： 在一个实施例中，磁带驱动系统包括软检测器，用于在第一时间间隔期间在第一信号样本块上执行检测算法的第一正向循环; 以及用于在几个时间间隔期间执行正向和反向循环的逻辑; 以及适于在第六时间间隔期间基于在第一块上执行解码算法来输出信号样本的第一解码块的逻辑，其中第二，第三，第四，第五和第六时间间隔的和大约相等于持续时间 到第一次间隔。
-
公开(公告)号：US08797670B2
公开(公告)日：2014-08-05
申请号：US13527508
申请日：2012-06-19
CPC分类号： G11B20/10046 , G11B5/008 , G11B20/10074 , G11B20/10287 , G11B2020/185 , G11B2020/1853 , G11B2220/90
摘要： In accordance with one embodiment, a data storage system includes a tape channel for reading precoded data from a magnetic tape medium to produce a signal, a soft detector adapted for calculating first soft information about each bit of the signal and sending the first soft information to a soft decoder, and the soft decoder positioned subsequent to the soft detector, the soft decoder being adapted for calculating second soft information about each bit of the signal and sending the second soft information to the soft detector, wherein the precoded data includes a characteristic of being passed through at least one precoder prior to being written to the magnetic tape medium, and wherein the soft detector provides automatic compensation for the precoded data. Other systems, methods, and computer program products for reading data using an adaptive soft-output detector are described according to more embodiments.
摘要翻译： 根据一个实施例，数据存储系统包括用于从磁带介质读取预编码数据以产生信号的磁带通道，软检测器，适于计算关于信号的每个位的第一软信息，并将第一软信息发送到 软解码器和位于软检测器之后的软解码器，软解码器适于计算关于信号的每个位的第二软信息，并将第二软信息发送给软检测器，其中预编码数据包括 在写入磁带介质之前通过至少一个预编码器，并且其中软检测器为预编码数据提供自动补偿。 根据更多实施例描述了使用自适应软输出检测器读取数据的其它系统，方法和计算机程序产品。
-
公开(公告)号：US08743498B2
公开(公告)日：2014-06-03
申请号：US13527473
申请日：2012-06-19
CPC分类号： G11B20/10046 , G11B5/008 , G11B20/10268
摘要： In one embodiment, a data storage system includes a tape channel for reading data from a magnetic tape medium to produce a signal, a noise whitening filter positioned subsequent to the tape channel adapted for receiving the signal, wherein the noise whitening filter is adapted for minimizing variance of its output signal, a soft detector adapted for receiving output from the noise whitening filter, the soft detector adapted for calculating first soft information about each bit of the signal and sending the first soft information to a soft decoder, and the soft decoder positioned subsequent to the soft detector, the soft decoder being adapted for calculating second soft information about each bit of the signal and sending the second soft information to the soft detector. Other systems, methods, and computer program products are described according to more embodiments.
摘要翻译： 在一个实施例中，数据存储系统包括用于从磁带介质读取数据以产生信号的磁带通道，位于适于接收信号的磁带通道之后的噪声白化滤波器，其中噪声增白滤波器适于最小化 其输出信号的方差，适于接收来自噪声白化滤波器的输出的软检测器，软检测器适于计算关于信号的每个位的第一软信息，并将第一软信息发送到软解码器，并且软解码器定位 在软检测器之后，软解码器适于计算关于信号的每个位的第二软信息，并将第二软信息发送到软检测器。 根据更多实施例描述其它系统，方法和计算机程序产品。
-
8.发明授权Data-dependent noise-predictive maximum likelihood detection (DD-NPML) for magnetic recording 有权用于磁记录的数据相关噪声预测最大似然检测（DD-NPML）公开(公告)号：US08670199B2
公开(公告)日：2014-03-11
申请号：US12753586
申请日：2010-04-02
IPC分类号： G11B5/09
CPC分类号： G11B20/10009 , G11B20/10046 , G11B20/10074 , G11B20/10175 , G11B20/10287 , G11B2220/90
摘要： In one embodiment, a method includes applying one or more whitening filters to an input stream of digitized samples from a magnetic data channel to produce a filtered sequence, performing one or more branch metric calculations to the filtered sequence to produce a branch metric, and applying a multi-state data-dependent noise-predictive maximum likelihood (DD-NPML) detector to the branch metric to produce an output stream. In another embodiment, a multi-channel data storage system includes a head for reading data from a storage medium, logic for applying one or more whitening filters to an input stream of digitized samples from a magnetic data channel to produce a filtered sequence, logic for performing one or more branch metric calculations to the filtered sequence to produce a branch metric, and logic for applying a multi-state DD-NPML detector to the branch metric to produce an output stream. Other systems and methods are described as well.
摘要翻译： 在一个实施例中，一种方法包括将一个或多个白化滤波器应用于来自磁数据信道的数字化样本的输入流，以产生经滤波的序列，对经滤波的序列执行一个或多个分支度量计算以产生分支度量，以及应用 用于产生输出流的分支度量的多状态数据相关噪声预测最大似然（DD-NPML）检测器。 在另一个实施例中，多通道数据存储系统包括用于从存储介质读取数据的头，用于将一个或多个白化滤波器应用于来自磁数据通道的数字化采样的输入流以产生滤波序列的逻辑，用于 对经滤波的序列执行一个或多个分支度量计算以产生分支度量，以及将多状态DD-NPML检测器应用于分支度量以产生输出流的逻辑。 还描述了其他系统和方法。
-
9.发明申请公开(公告)号：US20130279040A1
公开(公告)日：2013-10-24
申请号：US13454935
申请日：2012-04-24
CPC分类号： G11B20/1833 , G11B5/00813 , G11B20/10379 , G11B2020/185 , H03M5/145 , H03M13/1111 , H03M13/13 , H03M13/2957 , H03M13/3905 , H03M13/3972 , H03M13/6325
摘要： In one embodiment, a tape drive system includes a soft detector for executing a first forward loop of a detection algorithm on a first block of signal samples during a first time interval; and logic for executing forward and reverse loops during several time intervals; and logic adapted for outputting a first decoded block of signal samples based on the executing the decoding algorithm on the first block during a sixth time interval, wherein a sum of second, third, fourth, fifth, and sixth time intervals are about equal in duration to the first time interval.
摘要翻译： 在一个实施例中，磁带驱动系统包括软检测器，用于在第一时间间隔期间在第一信号样本块上执行检测算法的第一正向循环; 以及用于在几个时间间隔期间执行正向和反向循环的逻辑; 以及适于在第六时间间隔期间基于在第一块上执行解码算法来输出信号样本的第一解码块的逻辑，其中第二，第三，第四，第五和第六时间间隔的和大约相等于持续时间 到第一次间隔。
-
公开(公告)号：US08023223B2
公开(公告)日：2011-09-20
申请号：US12878722
申请日：2010-09-09
申请人： Nhan X. Bui , Giovanni Cherubini , Roy D. Cideciyan , Robert A. Hutchins , Jens Jelitto , Kazuhiro Tsuruta
发明人： Nhan X. Bui , Giovanni Cherubini , Roy D. Cideciyan , Robert A. Hutchins , Jens Jelitto , Kazuhiro Tsuruta
CPC分类号： G11B5/584
摘要： A weighted combining scheme exploits information from two servo channels operating in parallel. A timing-based servo module comprises two synchronous servo channels coupled respectively to receive two digital servo signals read from a data tape. Both channels have outputs for an unweighted parameter estimate and for a measure of the channel reliability. A weight computation module provides first and second weight signals using the measures of channel reliability from the servo channels. An offset computation module provides first and second offset terms which are summed with the unweighted parameter estimates. Multiplying nodes receive the unweighted parameter estimates and the weight signals and outputs offset weighted parameter estimates. A summing node receives the offset weighted parameter estimates and outputs a combined offset weighted parameter estimate to a servomechanism.
摘要翻译： 加权组合方案利用来自并行操作的两个伺服通道的信息。 基于定时的伺服模块包括分别耦合的两个同步伺服通道，以接收从数据磁带读取的两个数字伺服信号。 两个通道具有未加权参数估计的输出和通道可靠性的度量。 权重计算模块使用来自伺服信道的信道可靠性的测量来提供第一和第二加权信号。 偏移计算模块提供与未加权参数估计相加的第一和第二偏移项。 乘法节点接收未加权的参数估计和权重信号并输出偏移加权参数估计。 求和节点接收偏移加权参数估计，并将组合的偏移加权参数估计输出到伺服机构。
-
-
-
-
-
-
-
-
-
搜索结果
75 条记录 (耗时 0.041 秒)
