公开(公告)号：US20030048560A1

公开(公告)日：2003-03-13

申请号：US09993877

申请日：2001-11-05

Applicant: STMicroelectronics, Inc.

Inventor： Hakan Ozdemir

IPC: G11B005/09 ,  G11B019/02 ,  G11B005/596

CPC classification number: G11B5/59633

Abstract: A data-storage disk includes a disk sector for storing data and a servo wedge located at the beginning of the sector. The servo wedge indentifies the sector in conjunction with both an initial positioning of a read-write head and a data read or write operation. By using a servo wedge to provide both an initial head position on disk spin up and a head position during a read or write operation, one can increase a disk's data-storage capacity by reducing the number of, or altogether eliminating, spin-up wedges.

Abstract translation: 数据存储盘包括用于存储数据的磁盘扇区和位于扇区开头的伺服楔。 伺服楔同时结合读写头的初始定位和数据读或写操作来识别扇区。 通过使用伺服楔以在读或写操作期间提供磁盘上升的初始头部位置和头部位置，可以通过减少旋转楔子的数量或完全消除磁盘的数据存储容量来增加磁盘的数据存储容量 。

公开(公告)号：US20030048562A1

公开(公告)日：2003-03-13

申请号：US09993778

申请日：2001-11-05

Applicant: STMicroelectronics, Inc.

Inventor： Fereidoon Heydari ,  Hakan Ozdemir ,  Sadik O. Arf

IPC: G11B005/09 ,  G11B005/596

CPC classification number: G11B5/59633

Abstract: A new synchronous Partial Response Maximum Likelihood (PRML) servo is provided for a high track-per-inch disk-drive system. To increase the data capacity in hard disk drives (HDD), one can shorten the servo format and/or increase the track density. The new servo system has circuits that allow a high-performance and accurate system for positioning the read-write heads. The major circuits include burst demodulation, Viterbi detection, timing synchronization, and spin-up search. A highly linear discrete-fourier-transform (DFT) burst-demodulation circuit can demodulate high-density and low-signal-to-noise-ratio (SNR) position bursts. The Viterbi detection circuit includes a sync-mark detector and a Viterbi detector that are matched to at least two sets of Gray code ( e.g., null rate and {fraction (4/12)} rate) and pruned accordingly. The timing synchronization circuit includes phase restart and interpolating timing recovery (ITR) circuits to implement a fully digital timing recovery. The spin-up search circuit may include a robust multistage search circuit that detects a preamble and/or a DC field to search for an initial servo sector with a low error rate during spin up. In one example, the servo system samples each dibit 4 times throughout the entire servo sector uses PR4 equalization. The relatively low number of samples required for the system allows the servo format density to be near the channel bandwidth while increasing the SNR performance.

Abstract translation: 为高轨道/英寸磁盘驱动器系统提供了新的同步部分响应最大似然（PRML）伺服。 为了增加硬盘驱动器（HDD）的数据容量，可以缩短伺服格式和/或增加磁道密度。 新的伺服系统具有允许高性能和准确的系统定位读写头的电路。 主要电路包括突发解调，维特比检测，定时同步和自旋搜索。 高线性离散傅立叶变换（DFT）突发解调电路可以解调高密度和低信噪比（SNR）位置脉冲串。 维特比检测电路包括与至少两组格雷码（例如，1/4速率和4/12速率）匹配的同步标记检测器和维特比检测器，并相应地修剪。 定时同步电路包括实现全数字定时恢复的相位重启和内插定时恢复（ITR）电路。 上行搜索电路可以包括鲁棒的多级搜索电路，其检测前导码和/或DC场，以在旋转期间以低错误率搜索初始伺服扇区。 在一个示例中，伺服系统在整个伺服扇区中采样4次4位，使用PR4均衡。 系统所需的相对较少的样本数量允许伺服格式密度靠近信道带宽，同时增加SNR性能。

公开(公告)号：US20030030929A1

公开(公告)日：2003-02-13

申请号：US09993779

申请日：2001-11-05

Applicant: STMicroelectronics, Inc.

Inventor： Hakan Ozdemir

IPC: G11B005/09 ,  G11B005/596

CPC classification number: H03M7/16 ,  G11B20/10009 ,  G11B20/10055 ,  G11B20/10175 ,  G11B20/10222 ,  G11B20/10296 ,  G11B20/1403 ,  G11B20/18 ,  G11B2020/1282 ,  G11B2020/1284 ,  G11B2020/1484 ,  G11B2020/1859 ,  G11B2020/1863 ,  H03M13/41 ,  H03M13/6343

Abstract: A detector recovers servo data from a servo signal generated by a read-write head, and determines the head-connection polarity from the recovered servo data. Such a detector allows a servo circuit to compensate for a reversed-connected read-write head, and thus allows a manufacturer to forego time-consuming and costly testing to determine whether the head is correctly connected to the servo circuit.

Abstract translation: 检测器从由读写头产生的伺服信号中恢复伺服数据，并根据恢复的伺服数据确定磁头连接极性。 这种检测器允许伺服电路补偿反连接的读写头，并且因此允许制造商放弃耗时和昂贵的测试来确定磁头是否正确地连接到伺服电路。

公开(公告)号：US20040010749A1

公开(公告)日：2004-01-15

申请号：US10194660

申请日：2002-07-12

Applicant: STMicroelectronics, Inc.

Inventor： Hakan Ozdemir

IPC: H03M013/03

CPC classification number: G11B20/10064 ,  G11B20/10009 ,  H03M13/3961 ,  H03M13/4107 ,  H03M13/6343 ,  H03M13/6502

Abstract: An E2PR4 Viterbi detector includes a recovery circuit and receives a signal that represents a sequence of values, the sequence having a potential state. The recovery circuit recovers the sequence from the signal by identifying a surviving path to the potential state and, after identifying the surviving path, adding a modified branch metric to the path metric of the surviving path to generate an updated path metric for the potential state. Updating the path metric of the surviving path after the surviving path is selected allows the E2PR4 Viterbi detector to be smaller and/or faster than an E2PR4 Viterbi detector that updates the path metric before selecting the surviving path.

Abstract translation: E 2 PR4维特比检测器包括恢复电路并且接收表示值序列的信号，该序列具有潜在状态。 恢复电路通过识别到潜在状态的幸存路径来恢复序列，并且在识别存活路径之后，将修改的分支度量添加到幸存路径的路径度量以生成用于潜在状态的更新的路径度量。 选择存活路径之后更新幸存路径的路径度量允许E 2 PR4维特比检测器比选择剩余路径之前更新路径度量的E 2 PR4维特比检测器更小和/或更快。

公开(公告)号：US20030026016A1

公开(公告)日：2003-02-06

申请号：US09993986

申请日：2001-11-05

Applicant: STMicroelectronics, Inc.

Inventor： Fereidoon Heydari ,  Hakan Ozdemir

IPC: G11B020/06 ,  G11B005/596

CPC classification number: G11B5/59655 ,  G11B5/59688

Abstract: A new technique for Hard Disk Drive (HDD) servo-burst demodulation is provided. A 4-samples per dibit Discrete Fourier Transform (DFT) amplitude estimation is used to calculate the read-head servo-position error signal. Comparatively, the conventional method of burst demodulationnullcalled burst integrationnulltypically uses more than 8 samples/dibit. Consequently, the new 4-samples/dibit DFT burst-demodulation scheme requires fewer samples per dibit than does burst integration, thus reducing the disk space occupied by the burst data while increasing the performance as compared to burst integration. Furthermore, the DFT scheme does not require the samples to be synchronized to any particular points of the servo burst, and can include an averaging algorithm that further improves performance for a given Signal to Noise Ratio (SNR). Moreover, the same sample-clocking circuit that detects the Gray Code servo information can also implement the DFT burst-demodulation scheme to demodulate the servo burst.

Abstract translation: 提供了一种用于硬盘驱动器（HDD）伺服突发解调的新技术。 使用4个样本每二进制离散傅里叶变换（DFT）幅度估计来计算读取头伺服位置误差信号。 相比之下，传统的突发解调方法 - 称为突发集成 - 通常使用多于8个采样/双位。 因此，新的4采样/双位DFT突发解调方案比突发集成需要比每比特少的采样，因此与突发集成相比，降低了突发数据占用的磁盘空间，同时提高了性能。 此外，DFT方案不要求样本与伺服脉冲串的任何特定点同步，并且可以包括进一步改善给定信噪比（SNR）的性能的平均算法。 此外，检测格雷码伺服信息的相同采样时钟电路还可以实现DFT突发解调方案来解调伺服脉冲串。

公开(公告)号：US20030002189A1

公开(公告)日：2003-01-02

申请号：US09993869

申请日：2001-11-05

Applicant: STMicroelectronics, Inc

Inventor： Hakan Ozdemir

IPC: G11B005/09 ,  G11B005/596

CPC classification number: G11B5/59633 ,  G11B19/20 ,  G11B19/28

Abstract: A servo circuit includes a servo channel and a processor. The servo channel recovers servo data from servo wedges that identify respective data sectors on a data-storage disk. On spin up of the disk, the processor detects a spin-up wedge associated with one of the servo wedges and then detects the servo wedge. Once the servo wedge is detected, a head-position circuit can read the location data from the servo wedge to determine an initial position of the read-write head. By detecting a both a spin-up wedge and a servo wedge to determine an initial head position on disk spin up, such a servo circuit often allows one to increase the disk's storage capacity by reducing the lengths of the spin-up wedges.

Abstract translation: 伺服电路包括伺服通道和处理器。 伺服通道从数据存储盘上识别相应数据扇区的伺服楔恢复伺服数据。 在盘旋转时，处理器检测与其中一个伺服楔形件相关的升降楔，然后检测伺服楔。 一旦检测到伺服楔，则头位置电路可以从伺服楔读取位置数据，以确定读写头的初始位置。 通过检测旋转楔和伺服楔两者以确定磁盘上升时的初始磁头位置，这样的伺服电路通常允许通过减小旋转楔的长度来增加磁盘的存储容量。

公开(公告)号：US20040010748A1

公开(公告)日：2004-01-15

申请号：US10194659

申请日：2002-07-12

Applicant: STMicroelectronics, Inc.

Inventor： Hakan Ozdemir

IPC: H03M013/03

CPC classification number: G11B20/10064 ,  G11B20/10009 ,  H03M13/3961 ,  H03M13/4107 ,  H03M13/6343 ,  H03M13/6502

Abstract: An E2PR4 Viterbi detector receives a signal that represents a sequence of values, the sequence having a potential state. The detector includes a recovery circuit that recovers the sequence from the signal by identifying the surviving path to the potential state and simultaneously adding a modified branch metric to the path metric of the surviving path. By simultaneously identifying the surviving path and adding a modified branch metric to its path metric, such an E2PR4 Viterbi detector can operate faster than a conventional add-compare-select E2PR4 Viterbi detector.

Abstract translation: E 2 PR4维特比检测器接收表示值序列的信号，该序列具有电位状态。 检测器包括恢复电路，其通过识别到潜在状态的幸存路径并且同时将修改的分支度量添加到幸存路径的路径度量来从信号恢复序列。 通过同时识别存活路径并将修改的分支度量添加到其路径度量，这样的E 2 PR4维特比检测器可以比传统的加法比较选择E 2 PR4维特比检测器更快地进行操作。

公开(公告)号：US20030053245A1

公开(公告)日：2003-03-20

申请号：US09993876

申请日：2001-11-05

Applicant: STMicroelectronics, Inc.

Inventor： Hakan Ozdemir

IPC: G11B005/596 ,  G11B005/09

CPC classification number: G11B5/59633 ,  G11B19/20 ,  G11B19/28

Abstract: A servo circuit includes a servo channel and a processor. The servo channel recovers servo data from servo wedges that identify respective data sectors on a data-storage disk. The processor detects one of the servo wedges on spin up of the disk, i.e., while the disk is attaining or after the disk attains an operating speed. By detecting a servo wedge instead of a spin-up wedge to determine an initial head position on disk spin up, such a servo circuit allows one to increase the disk's storage capacity by reducing the number of, or altogether eliminating, spin-up servo wedges from the disk.

Abstract translation: 伺服电路包括伺服通道和处理器。 伺服通道从数据存储盘上识别相应数据扇区的伺服楔恢复伺服数据。 处理器检测到在盘旋转时的伺服楔形中的一个，即在盘达到或在盘达到操作速度之后。 通过检测伺服楔而不是旋转楔以确定磁盘上升的初始磁头位置，这样的伺服电路允许通过减少旋转伺服楔的数量或完全消除磁盘的存储容量来增加磁盘的存储容量 从磁盘。

公开(公告)号：US20030011918A1

公开(公告)日：2003-01-16

申请号：US09994009

申请日：2001-11-05

Applicant: STMicroelectronics, Inc.

Inventor： Fereidoon Heydari ,  Hakan Ozdemir

IPC: G11B005/09 ,  G11B005/596

CPC classification number: G11B20/10009 ,  G11B5/59633 ,  G11B20/10055 ,  G11B20/10074 ,  G11B20/10296 ,  G11B20/1217 ,  G11B20/1496 ,  G11B27/3027 ,  G11B2020/1484 ,  G11B2220/2516 ,  H03M7/16

Abstract: A new technique incorporates a 1/4-rate Hard Disk Drive (HDD) servo-data encoding into a Partial Response Maximum Likelihood (PRML) read channel. The limitation of the HDD servo-track writer is the maximum frequency associated with writing the servo data while maintaining a level of data alignment between the data in the adjacent tracks (coherency). The 1/4 code allows the servo data to be written at the maximum coherency bandwidth. Specifically, the data is read back (or sampled) at twice the write frequency. This increases the data redundancy while also increasing the data density and the disk storage capacity. The 1/4 coding can also be applied to conventional HDD dibit coding. Specifically, the 1/4-coding scheme reads each dibit-coded servo-data transition 01 as 0011, and reads each non-transition 00 (or 0) as 0000. The 1/4 coding and its matched Viterbi detector can also increase the data detection in comparison to conventional peak-detection schemes. And although the 1/4 coding scheme is described in conjunction with a PR4-type servo channel, it can also be used with an EPR4-type servo channel and other types of servo channels.

Abstract translation: 一种新技术将1/4速度硬盘驱动器（HDD）伺服数据编码结合到部分响应最大似然（PRML）读通道中。 HDD伺服磁道写入器的限制是与伺服数据写入相关联的最大频率，同时保持相邻轨道中的数据之间的数据对齐水平（相干性）。 1/4代码允许伺服数据以最大相干带宽写入。 具体来说，以写入频率的两倍读取（或采样）数据。 这增加了数据冗余，同时也增加了数据密度和磁盘存储容量。 1/4编码也可以应用于传统的HDD双编码。 具体地说，1/4编码方式将每个二进制编码的伺服数据转换01读取为0011，并将每个非转换00（或0）读取为0000。1/4编码及其匹配的维特比检测器也可以增加 数据检测与传统的峰值检测方案相比。 虽然1/4编码方案与PR4型伺服通道一起描述，但也可以与EPR4型伺服通道和其他类型的伺服通道一起使用。