摘要:
Various embodiments of the present invention provide systems and methods for data processing. For example, a method for data processing is disclosed that includes receiving a codeword that has at least a first circulant with a plurality of data bits and a first circulant parity bit, a second circulant with a plurality of data bits and a second circulant parity bit, and one or more codeword parity bits. The methods further include decoding the codeword using the one or more codeword parity bits to access the first circulant and the second circulant, performing a first circulant parity check on the first circulant, and performing a second circulant parity check on the second circulant.
摘要:
Various embodiments of the present invention provide systems, devices and methods for data processing. As an example, a data processing device is discussed that include a data encoding system and a data decoding system. The data encoding system is operable to receive a data input, and to: apply a maximum transition run length encoding to the data input to yield a run length limited output; apply a low density parity check encoding algorithm to the run length limited output to yield a number of original parity bits; apply a precode algorithm to the original parity bits to yield precoded parity bits; and combine the precoded parity bits and a derivative of the run length limited output to yield an output data set.
摘要:
In exemplary embodiments, a skewed interleaving function for iterative code systems is described. The skewed interleaving function provides a skewed row and column memory partition and a layered structure for re-arranging data samples read from, for example, a first channel detector. An iterative decoder, such as an iterative decoder based on a low-density parity-check code (LDPC), might employ an element to de-skew the data from the interleaved memory partition before performing iterative decoding of the data, and then re-skew the information before passing decoded samples to the de-interleaver. The de-interleaver re-arranges the iterative decoded data samples in accordance with an inverse of the interleaver function before passing the decoded data samples to, for example, a second channel detector.
摘要:
Various embodiments of the present invention provide systems and methods for media defect detection. For example, a media defect detection systems is disclosed that includes a data input derived from a medium, a fast envelope calculation circuit that receives the data input and provides a fast decay envelope value based on the data input, a slow envelope calculation circuit that receives the data input and provides a slow decay envelope value based on the data input, and a media defect detection circuit. The media defect detection circuit receives the slow decay envelope value and the fast decay envelope value, calculates a ratio value of the fast decay envelope value to the slow decay envelope value, and asserts a defect output based at least in part on the comparison of the ratio value to a defect threshold value.
摘要:
In a hard-disc drive, a defect region on the hard disc is detected by generating two statistical measures (e.g., β1(k) and β2(k)) based on signal values (e.g., x[n] or y[n]) and soft-decision values (e.g., L[n]) corresponding to the signal values. The measures are compared to detect the location of the defect region of the hard drive. Using the soft-decision values reduces fluctuations in a ratio of the statistical measures compared to a ratio formed from statistical measures that are not based on soft-decision values, resulting in a more-reliable test for detecting defect regions.
摘要翻译:在硬盘驱动器中,通过基于信号值(例如,x [n]或x(n))生成两个统计度量(例如,&bgr; 1(k)和&bgr; 2(k))来检测硬盘上的缺陷区域 y [n])和软判决值(例如,L [n])。 比较措施来检测硬盘驱动器缺陷区域的位置。 使用软判决值可减少统计度量与由不基于软判决值的统计测量形成的比率的比率的波动,导致检测缺陷区域的更可靠的测试。
摘要:
Various systems and methods for tri-column code based error reduction are disclosed herein. For example, a digital information system is disclosed that includes channel detector. Such a channel detector receives an encoded data set and provides an output representing the encoded data set. The exemplary system further includes a decoder that receives the first output and is operable to perform three slope parity checks on the received first output. In turn, the decoder provides another output representing the encoded data set.
摘要:
Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is disclosed that includes a processing loop circuit having a data detector and a soft decision decoder. The data detector provides a detected output, and the soft decision decoder applies a soft decoding algorithm to a derivative of the detected output to yield a soft decision output and a first hard decision output. The systems further include a queuing buffer and a hard decision decoder. The queuing buffer is operable to store the soft decision output, and the hard decision decoder accesses the soft decision output and applies a hard decoding algorithm to yield a second hard decision output. The data detector is operable to perform a data detection on a derivative of the soft decision output if the soft decision decoder and the hard decision decoder fail to converge
摘要:
Various systems and methods for code based error reduction. For example, in one digital information system including a channel detector and a decoder, the channel detector receives an encoded data set and is operable to perform a column parity check. The channel detector provides an output representing the encoded data set. The decoder receives the output from the channel detector and is operable to perform two checks. The two checks may be one of: two pseudo-random parity checks, a pseudo-random parity check and a slope parity check, and two slope parity checks. In addition, the decoder provides another output representing the encoded data set.
摘要:
Various systems and methods for tri-column code based error reduction are disclosed herein. For example, a digital information system is disclosed that includes channel detector. Such a channel detector receives an encoded data set and provides an output representing the encoded data set. The exemplary system further includes a decoder that receives the first output and is operable to perform three slope parity checks on the received first output. In turn, the decoder provides another output representing the encoded data set.
摘要:
Various embodiments of the present invention provide systems and methods for processing information. For example, a decoding system is disclosed that includes a de-interleaver. The de-interleaver is operable to receive an interleaved codeword that includes two or more reduced codewords interleaved together. Further, the de-interleaver is operable to provide a representation of the two or more reduced codewords. The systems also include a decoder that is operable to decode the two or more reduced codewords. In some instances of the aforementioned embodiments, the decoder is an LDPC decoder that is tailored to the size of one or both of the two or more reduced codewords.