公开(公告)号：US20030174781A1

公开(公告)日：2003-09-18

申请号：US10363908

申请日：2003-03-07

发明人： Akira Itou ,  Toshihiko Hirose

IPC分类号： H04L007/00 ,  H04L005/12 ,  H04L023/02

CPC分类号： H04L7/041 ,  G11B20/10009 ,  G11B20/10055 ,  G11B20/10296 ,  G11B20/1426 ,  G11B20/1833 ,  G11B27/3027 ,  G11B2020/1287 ,  G11B2020/1438 ,  G11B2220/90 ,  H03M13/33

摘要： There is provided a method of detecting a block sync signal in which a sync signal and code sequence can be distinguished from each other to recognize the head of a block composed of a plurality of code words at the time of data reading or reception. A sync word detector (10) is supplied with a window signal Sync_window generated based on a parity OK signal supplied from a parity check circuit (12) and indicating a period between the sync word included in signal read from the medium (1) and the ID information, and detects the sync word as to a bit string detected by a PRML Viterbi detector (6) with the use of the Sync_window signal.

摘要翻译： 提供了一种检测块同步信号的方法，其中同步信号和码序列可以彼此区分，以识别在数据读取或接收时由多个码字组成的块的头。 同步字检测器（10）被提供有基于从奇偶校验电路（12）提供的奇偶校验OK信号产生的窗口信号Sync_window，并指示包括在从介质（1）读取的信号中的同步字与 ID信息，并且通过使用Sync_window信号来检测由PRML维特比检测器（6）检测到的位串的同步字。

公开(公告)号：US5406569A

公开(公告)日：1995-04-11

申请号：US966844

申请日：1992-10-27

申请人： Masaaki Isozaki

发明人： Masaaki Isozaki

IPC分类号： G11B20/14 ,  H03M5/14 ,  H03M13/31 ,  H03M13/33 ,  H03M13/35 ,  H03M13/00

CPC分类号： G11B20/1426 ,  H03M13/31 ,  H03M13/33 ,  H03M13/35 ,  H03M5/145 ,  G11B2020/1438 ,  G11B2020/148 ,  H04L7/08

摘要： The present invention is directed to a digital data error correcting apparatus in which an error correction capability can be considerably improved in a digital signal transmission system when a digital modulation code is decoded. In a minimum distance decoding method, when a plurality of reference samples having equal minimum Hamming distance relative to a digital modulation code exist, on the basis of the probability that an error will occur in the respective bits, respective bits are weighted, and a reference sample having the minimum distance from the input sample is selected from a plurality of reference samples to thereby correct an error. Further, the present invention is directed to a digital sync. detection apparatus in which an ability for detecting a sync. pattern can be considerably improved without degrading the probability that a pseudo-sync. signal will occur. A detection interval of a predetermined cycle is set in a sync. pattern of a predetermined cycle whose Hamming distance between it and a digital modulation code is larger than k by a detection window signal generator circuit (40), and (k-1) bit error of the sync. pattern can be corrected during this detection interval.

摘要翻译： 本发明涉及一种数字数据纠错装置，其中当解码数字调制码时，数字信号传输系统中的纠错能力可以大大提高。 在最小距离解码方法中，当存在相对于数字调制码具有相等的最小汉明距离的多个参考样本时，基于在各个比特中将发生错误的概率，对各个比特进行加权， 从多个参考样本中选择与输入样本具有最小距离的样本，从而校正错误。 此外，本发明涉及数字同步。 检测装置，其中检测同步的能力。 模式可以大大提高，而不会降低伪同步的概率。 信号会发生。 同步设定预定周期的检测间隔。 通过检测窗口信号发生器电路（40），其与数字调制码的汉明距离大于k的预定周期的图案，以及（k-1）同步的位错误。 在该检测间隔期间可以校正图案。

公开(公告)号：US4862296A

公开(公告)日：1989-08-29

申请号：US244863

申请日：1988-09-15

申请人： Noboru Murabayashi ,  Keiji Kanota

发明人： Noboru Murabayashi ,  Keiji Kanota

IPC分类号： G11B5/09 ,  G11B20/14 ,  H03L7/093 ,  H04N5/93

CPC分类号： G11B20/1419 ,  G11B20/1426 ,  G11B2020/1438 ,  G11B2220/90

摘要： A clock regeneration circuit for use in data reproducing apparatus which reproduces and demodulates digital data that has been recorded on a magnetic medium in accordance with different types of modulation having different recording densities, such as biphase-mark modulation and 8-10 modulation, respectively. The clock regeneration circuit includes a phase locked loop for regenerating a clock signal from the clock component included in the reproduced data and comprises a switchable voltage controlled oscillator for selecting the frequency of a reference signal generated thereby in correspondence with the type of modulation which had been used for recording. Also included in the clock regeneration circuit is a phase comparator and a switchable low pass filter for supplying the output of the phase comparator to the voltage controlled oscillator, the time constant of the filter being selected in correspondence with the type of modulation that was used for recording. A control circuit controls the frequency selection of the voltage controlled oscillator and the time constant selection of the low pass filter in accordance with data signals supplied thereto.

公开(公告)号：US4531153A

公开(公告)日：1985-07-23

申请号：US437700

申请日：1982-10-29

申请人： Kenji Watanabe

发明人： Kenji Watanabe

IPC分类号： H03M5/04 ,  G11B20/14 ,  H03M7/00 ,  H04L25/49 ,  H04N5/926 ,  H04N7/26 ,  H04N9/804 ,  H04N9/808 ,  H04N11/04 ,  H04N5/16

CPC分类号： H04L25/4906 ,  G11B20/1426 ,  H04N5/926 ,  G11B2020/1434 ,  G11B2020/1438

摘要： A system of encoding an original binary digital video signal comprised of a plurality of first 8-bit words having an absolute value and a digital sum variation, to produce an encoded binary digital video signal, converts each first 8-bit word into a second 8-bit word also having an absolute value and a digital sum variation such that, with respect to predetermined groups of correlative first 8-bit words, that is, first 8-bit words having absolute values which are close to each other, second 8-bit words corresponding to the first 8-bit words in each respective group have the same digital sum variation; and then inverts every alternate m second 8-bit words, where m=1, 2, 3 . . . , to form the encoded binary digital video signal with substantially reduced DC content while maintaining the same recording bit rate.

摘要翻译： 对由具有绝对值和数字和变化的多个第一8位字组成的原始二进制数字视频信号进行编码以产生编码二进制数字视频信号的系统将每个第一8位字转换成第二8位字 位字也具有绝对值和数字和变化，使得对于相关的第一8位字的预定组，即具有彼此接近的绝对值的第一8位字，第二8- 对应于每个相应组中的第一8位字的位字具有相同的数字和变化; 然后反转每个交替的m个第二个8位字，其中m = 1,2,3。 的。 的。 ，以在保持相同的记录比特率的同时形成具有显着降低的DC内容的编码的二进制数字视频信号。

公开(公告)号：US20040052190A1

公开(公告)日：2004-03-18

申请号：US10451147

申请日：2003-06-27

发明人： Yoichiro Sako ,  Akiya Saito ,  Yoshinobu Usui ,  Yoriaki Kanada ,  Tomihiro Nakagawa ,  Tatsuya Inokuchi ,  Shunsuke Furukawa ,  Takashi Kihara

IPC分类号： G11B007/0045

CPC分类号： G11B7/261 ,  G11B20/10 ,  G11B20/1426 ,  G11B2020/1438 ,  H03M5/145

摘要： The present invention is relative with a method for recording further data on a recording medium on which there re pre-recorded data obtained on modulating M-bit data to N-bit data, where M

摘要翻译： 本发明与用于在将M位数据调制获得的预先记录的数据转换为N位数据的记录介质上记录另外的数据的方法相关，其中M

公开(公告)号：US5633632A

公开(公告)日：1997-05-27

申请号：US592588

申请日：1996-01-17

申请人： Kihei Ido ,  Masako Yamada ,  Hideaki Kosaka ,  Masayuki Ohta

发明人： Kihei Ido ,  Masako Yamada ,  Hideaki Kosaka ,  Masayuki Ohta

IPC分类号： G11B15/46 ,  G11B15/467 ,  G11B20/14 ,  G11B27/30 ,  H04N5/92 ,  H04N5/926 ,  H03M7/00

CPC分类号： G11B20/1426 ,  G11B15/463 ,  G11B15/4678 ,  G11B27/3027 ,  G11B27/3063 ,  H04N5/9264 ,  G11B2020/1438 ,  H04N5/9201 ,  H04N5/9267

摘要： A data conversion method, wherein a sequence of first r-bit datawords is divided into groups of x bits where x is the least common multiple of r and m, an arbitrary first dataword selected from x/r groups of first datawords is divided into x/m, an m-bit second dataword is formed by appending r/(x/m)-bit data, obtained by dividing the first dataword into x/m, to the LSB or MSB side of one or other of the non-divided first datawords, and the word-converted m-bit second dataword is converted to an n-bit codeword (m

摘要翻译： 一种数据转换方法，其中第一r位数据字的序列被划分为x位的组，其中x是r和m的最小公倍数，从x / r组的第一数据字中选择的任意第一数据字被划分为x / m，通过将通过将第一数据字划分为x / m获得的r /（x / m）位数据附加到未分割的一个或另一个的LSB或MSB侧来形成m位第二数据字 第一数据字和字转换的m位第二数据字被转换成n位码字（m

公开(公告)号：US5365232A

公开(公告)日：1994-11-15

申请号：US120857

申请日：1993-08-31

申请人： Kihei Ido ,  Masayuki Ohta

发明人： Kihei Ido ,  Masayuki Ohta

IPC分类号： G06F13/40 ,  G11B5/008 ,  G11B5/588 ,  G11B5/592 ,  G11B15/46 ,  G11B15/467 ,  G11B15/473 ,  G11B20/14 ,  H03M7/00

CPC分类号： G11B15/473 ,  G06F13/4018 ,  G11B15/463 ,  G11B15/4678 ,  G11B20/1426 ,  G11B5/0086 ,  G11B5/588 ,  G11B2020/1438 ,  G11B5/5921 ,  G11B5/5922

摘要： A data conversion method from m bits of data words into n bits of code words in recording or transmission, in which n is larger than m. A number of bit "0" arranged between one bit "1" and a next bit "1" is restricted to at most 4 in a code string of each code word, and a pair of groups of the n bits of code words corresponding to CDSs (code word digital sum) of two codes +1 and -1 are allowed to correspond to the m bits of data words. One of the two codes +1 and -1 is selectively used according to a DSV (digital sum variation) control signal to convert the m bits of data word into the n bits of code word. A pilot signal formation method using the data conversion method for obtaining a tracking error signal in a magnetic recording and reproducing apparatus, and a rotary magnetic head device for use in a magnetic recording and reproducing apparatus are also disclosed.

摘要翻译： 一种将数据字的m位数据转换成n个大于m的码字的n位的数据转换方法。 在每个代码字的代码串中，在一个位“1”和下一个位“1”之间布置的位数“0”被限制在最多4个，并且对应于 允许两个代码+1和-1的CDS（码字数字和）对应于数据字的m位。 根据DSV（数字和变化）控制信号，有选择地使用两个代码+1和-1中的一个，以将数据字的m位转换成码字的n位。 还公开了一种使用用于获得磁记录和再现装置中的跟踪误差信号的数据转换方法的导频信号形成方法和用于磁记录和再现装置的旋转磁头装置。

公开(公告)号：US5341134A

公开(公告)日：1994-08-23

申请号：US998695

申请日：1992-12-30

申请人： Boonsieng Benjauthrit

发明人： Boonsieng Benjauthrit

IPC分类号： H03M7/14 ,  G11B20/14 ,  H03M5/14 ,  H03M7/20

CPC分类号： G11B20/1426 ,  H03M5/145 ,  G11B2020/1438

摘要： Digital data recording/reproducing apparatus which uses a simple coding scheme for DC channel codes of the form M/N where M=N-1 and M and N are positive integers.

摘要翻译： 数字数据记录/再现装置，其使用M / N形式的M / N形式的直流信道码的简单编码方案，其中M = N-1，M和N是正整数。

公开(公告)号：US4517552A

公开(公告)日：1985-05-14

申请号：US380336

申请日：1982-05-20

申请人： Norihisa Shirota ,  Takao Abe

发明人： Norihisa Shirota ,  Takao Abe

IPC分类号： H04L25/49 ,  G11B5/09 ,  G11B20/14 ,  H03M7/14 ,  H03K13/24

CPC分类号： G11B20/1426 ,  G11B2020/1438

摘要： A method and apparatus are provided for encoding successive n-bit information words into successive m-bit code words wherein m>n. Each n-bit information word is assigned with a respective set of m-bit code words. Each set of code words is comprised of either two or four words. The words in each two-word set have zero disparity, and their first bits are of opposite logical sets. In the four-word sets, two words have positive disparity and their first bits are of opposite logical sense, and the other two words have negative disparity and their first bits also are of opposite logical sense. The particular m-bit code word that is selected from the set associated with the n-bit word commences with the same bit as the last bit of the immeditely preceding code word, and the selected code word exhibits a disparity that, when combined with the digital sum variation of the preceding encoded code words, reduces the overall digital sum variation toward zero.

摘要翻译： 提供了一种方法和装置，用于将连续的n位信息字编码为连续m位码，其中m> n。 每个n位信息字被分配有相应的一组m位代码字。 每组代码字由两个或四个单词组成。 每个双字集合中的单词具有零差异，并且它们的第一位是相反的逻辑集合。 在四个字组中，两个字具有正差异，其第一位具有相反的逻辑意义，另外两个字具有负差异，其第一位也具有相反的逻辑意义。 从与n位字相关联的集合中选择的特定m位代码字与与先前的代码字的最后位相同的位开始，并且所选择的代码字表现出差异，当与 上述编码码字的数字和变化将整数数字和变化减小到零。

公开(公告)号：US20050152255A1

公开(公告)日：2005-07-14

申请号：US10509887

申请日：2004-01-29

申请人： Takashi Kihara ,  Tatsuya Inokuchi ,  Yoichiro Sako

发明人： Takashi Kihara ,  Tatsuya Inokuchi ,  Yoichiro Sako

IPC分类号： G11B20/10 ,  G11B20/00 ,  G11B20/12 ,  G11B20/14 ,  G11B27/30 ,  G11B27/34 ,  G11B27/36 ,  G11B5/58

CPC分类号： G11B27/34 ,  G11B20/00086 ,  G11B20/0021 ,  G11B20/1426 ,  G11B27/3063 ,  G11B27/36 ,  G11B2020/1438 ,  G11B2020/1457 ,  G11B2020/1461 ,  G11B2220/20 ,  G11B2220/216 ,  G11B2220/218 ,  G11B2220/2545

摘要： Main data and a sub code supplied from input terminals 1a and 1b are processed by encoders 2a and 2b, respectively. The encoded main data and sub code are supplied to an EFM modulating portion 4 through a multiplexer 3. The EFM modulating portion 4 is composed of an 8-14 converting portion 5a and a connection bit selecting portion 5b. For the EFM modulating portion 4, a DSV normal controlling portion 7a and a DSV special controlling portion 7b are disposed. In only a predetermined region designated on an optical disc, the DSV special control is performed. The DSV special control causes the absolute value of the DSV to increase so that data will be prevented from being normally reproduced. The normal control causes the absolute value of the DSV to converge at 0. When data is reproduced from the optical disc, if the reproduction state of the predetermined region is abnormal, it is determined that the disc is an original disc. An encryption key can be recorded in the predetermined region.

摘要翻译： 主数据和从输入端子1a和1b提供的子代码分别由编码器2a和2b处理。 经编码的主数据和子码通过多路复用器3提供给EFM调制部分4。 EFM调制部分4由8-14转换部分5a和连接位选择部分5b组成。 对于EFM调制部分4，设置DSV正常控制部分7a和DSV专用控制部分7b。 在仅在光盘上指定的预定区域中，执行DSV特殊控制。 DSV特殊控制使DSV的绝对值增加，从而防止数据正常再现。 通常的控制使得DSV的绝对值收敛到0.当从光盘再现数据时，如果预定区域的再现状态异常，则确定该盘是原始盘。 可以在预定区域中记录加密密钥。