Techniques For Identifying Servo Sectors In Storage Devices
    22.
    发明申请
    Techniques For Identifying Servo Sectors In Storage Devices 有权
    用于识别存储设备中的伺服扇区的技术

    公开(公告)号:US20080204926A1

    公开(公告)日:2008-08-28

    申请号:US11677854

    申请日:2007-02-22

    IPC分类号: G11B5/596

    摘要: Techniques are provided for identifying the servo sectors in a track on a data storage device. A data storage device identifies the servo sectors in a track by reading distributed index bits from multiple servo sectors in a track. The data storage device analyzes only one index bit from each servo sector to identify the index of a track. In some embodiments, the index of a track can be identified after examining the index bits stored in a particular number of consecutive servo sectors, even in the presence of errors. The index bits in each track can have an error tolerance with a minimum Hamming distance greater than one. In other embodiments, a data storage device compares a sliding window of the index bits read from the servo sectors to all possible N-bit vectors that exist within a pattern of the index bits stored on a track.

    摘要翻译: 提供了用于识别数据存储设备上的轨道中的伺服扇区的技术。 数据存储装置通过从轨道中的多个伺服扇区读取分布式索引位来识别轨道中的伺服扇区。 数据存储设备仅分析来自每个伺服扇区的一个索引位以识别轨道的索引。 在一些实施例中,即使存在错误,也可以在检查存储在特定数量的连续伺服扇区中的索引位之后识别轨道的索引。 每个轨道中的索引位可以具有大于1的最小汉明距离的误差容差。 在其他实施例中,数据存储装置将从伺服扇区读取的索引位的滑动窗口与存储在轨道上的索引位的模式中存在的所有可能的N位向量进行比较。

    Method for bit-byte synchronization in sampling a data string
    25.
    发明申请
    Method for bit-byte synchronization in sampling a data string 有权
    数据串采样中位字节同步的方法

    公开(公告)号:US20050265493A1

    公开(公告)日:2005-12-01

    申请号:US10856706

    申请日:2004-05-28

    摘要: Bit and byte synchronization for sampling and decoding a data string is provided a single data field u. The data string x has pre-pended to it a short string of is (ones), followed by u to yield a string y= . . . 1111, u, x. The string is pre-coded by convolution with 1/(1⊕D2). PRML-sampling of y starts at an initial phase, and vectors are obtained from that string by sampling at pre-selected phases following the initial sampling point. The vectors of y are compared with vectors corresponding to PRML samples of an initial set of bits in u obtained at predetermined phases. The pair of y, u vectors exhibiting the minimum Euclidian distance yields a sampling correction value by which the initial sampling phase is corrected and a new initial sampling point preceding x is determined. Here, bit and byte synchronization have been achieved and sampling of x proceeds at the corrected phase, from the new initial sampling point.

    摘要翻译: 为数据串采样和解码的位和字节同步提供单个数据字段u。 数据串x已经预先提供了一个短串的(1),其次是u得到一个字符串y =。 。 。 1111,u,x。 该字符串通过卷积与1 /(1⊕D 2 )进行预编码。 y的PRML采样从初始阶段开始,并且通过在初始采样点之后的预选阶段进行采样从该串中获得向量。 将y的向量与对应于在预定阶段获得的u的初始位组的PRML样本相对应的向量进行比较。 呈现最小欧几里德距离的一对y,u向量产生采样校正值,通过该取样校正值校正初始采样相位,并且确定x之前的新的初始采样点。 这里,已经实现了比特和字节同步,并且从新的初始采样点在校正阶段进行x的采样。

    Byte synchronization system and method using an error correcting code
    26.
    发明授权
    Byte synchronization system and method using an error correcting code 失效
    字节同步系统和使用纠错码的方法

    公开(公告)号:US06089749A

    公开(公告)日:2000-07-18

    申请号:US889363

    申请日:1997-07-08

    摘要: A byte synchronization detection system and method in which a vector subtractor circuit determines an error vector between a current read data pattern and a synchronization bit pattern, and an offset adder circuit determines a Hamming Distance of the next read data pattern by adding the difference between the Hamming Distance from current error vector to the synchronization bit pattern and the Hamming Distance from the next error vector to the synchronization bit pattern. The Hamming Distance is determined by selected elements of the error vector which are the output from the vector subtractor circuit. The offset adder circuit determines a difference between the Hamming Distance of the current read data pattern and of the next read data pattern. The synchronization bit pattern is between 16 and 18 bits in length, inclusive. This approach reduces the probability of synchronization failure and/or mis-synchronization about 4 orders of magnitude over conventional approaches, while also reducing the length of the byte synchronization pattern to 16 bits.

    摘要翻译: 一种字节同步检测系统和方法,其中矢量减法器电路确定当前读取数据模式和同步位模式之间的误差向量,并且偏移加法器电路通过将下一个读取数据模式之间的差值相加来确定下一个读取数据模式的汉明距离 汉明距当前误差矢量到同步位模式的距离以及从下一个误差向量到同步位模式的汉明距离。 汉明距离由作为向量减法器电路的输出的误差向量的选定元素确定。 偏移加法器电路确定当前读取数据模式的汉明距离和下一个读取数据模式之间的差值。 同步位模式长度在16到18位之间,包括端点。 与常规方法相比,该方法降低了同步失败和/或误差约4个数量级的概率,同时还将字节同步模式的长度减小到16位。

    Defect tolerant binary synchronization mark
    27.
    发明授权
    Defect tolerant binary synchronization mark 失效
    缺陷容错二进制同步标记

    公开(公告)号:US5999110A

    公开(公告)日:1999-12-07

    申请号:US24422

    申请日:1998-02-17

    摘要: Disclosed is an error tolerant binary encoded synchronization mark concatenated with a known pattern, such as a VFO pattern, comprising an encoded pattern of a fixed plurality of bits, the encoded synchronization pattern being at maximum Hamming distance from the concatenated known pattern for the number of bits in the fixed plurality of bits. The error tolerant synchronization mark may also be concatenated with the VFO pattern seen in reverse, and the synchronization pattern additionally is at maximum Hamming distance from the concatenated known VFO pattern seen in reverse.

    摘要翻译: 公开了一种容错二进制编码同步标记,其与已知模式连接,诸如VFO模式,包括固定多个位的编码模式,编码同步模式距离级联已知模式的最大汉明距离为 固定多个比特中的比特。 误差同步标记也可以与反向看到的VFO模式相连,并且同步模式另外与从反向看到的级联的已知VFO模式相距最大的汉明距离。

    Techniques for reducing error propagation using modulation codes having a variable span
    30.
    发明申请
    Techniques for reducing error propagation using modulation codes having a variable span 有权
    使用具有可变跨度的调制码减少误差传播的技术

    公开(公告)号:US20070157067A1

    公开(公告)日:2007-07-05

    申请号:US11326357

    申请日:2006-01-04

    IPC分类号: H03M13/00

    摘要: Techniques are provided for reducing error propagation in encoded data using Fibonacci modulation codes. The Fibonacci modulation codes have a Fibonacci base with a variable span that limits error propagation. Some of the elements in the Fibonacci base have a larger span than limited span elements in the base. Errors occurring in bit positions of an encoded sequence that correspond to the limited span elements do not propagate to adjacent bytes in the decoded sequence. The Fibonacci modulation codes can also have a relatively high code rate.

    摘要翻译: 提供了使用斐波纳契调制码减少编码数据中的误差传播的技术。 斐波纳契调制码具有可变跨度的斐波那契基极,限制误差传播。 斐波那契基地中的一些元素的跨度比底座中的有限跨度元素大。 对应于有限跨度元件的编码序列的比特位置发生的错误不会传播到解码序列中的相邻字节。 斐波纳契调制码也可以具有相对较高的码率。