Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a variable iteration data processing system is disclosed that includes a first detector, a second detector, a decoder and a unified memory buffer. An input data set is received by the first detector that performs a data detection and provides a first detected data set. The decoder receives a derivative of the first detected data set and performs a decoding operation that yields a decoded data set. In some cases, the derivative of the first detected data set is an interleaved version of the first detected data set. The decoded data set is written to a unified memory buffer. The first decoded data set is retrievable from the unified memory buffer and a derivative thereof is provided to the second detector. In some cases, the derivative of the decoded is a de-interleaved version of the decoded data set.

Abstract: 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.

Abstract: 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.

Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a variable iteration data processing system is disclosed that includes a first detector, a second detector, a decoder and a unified memory buffer. An input data set is received by the first detector that performs a data detection and provides a first detected data set. The decoder receives a derivative of the first detected data set and performs a decoding operation that yields a decoded data set. In some cases, the derivative of the first detected data set is an interleaved version of the first detected data set. The decoded data set is written to a unified memory buffer. The first decoded data set is retrievable from the unified memory buffer and a derivative thereof is provided to the second detector. In some cases, the derivative of the decoded is a de-interleaved version of the decoded data set.

Abstract: A method and apparatus are disclosed for detecting a synchronization mark in a received signal. The received signal is processed to compensate for a DC bias in the received signal, such as subtracting an average of a block of received samples from each sample in the block. A distance metric, such as a sum of square differences, is computed between the DC compensated received signal and an ideal version of the received signal expected when reading the synchronization mark. The synchronization mark is detected if the distance metric satisfies predefined criteria. The ideal version of the received signal can optionally be processed to compensate for a DC bias in the synchronization mark. A search for the synchronization mark search can be limited to time cycles that match a known phase.

Abstract: A method and apparatus are disclosed for detecting a synchronization mark in a received signal. The received signal is processed to compensate for a DC bias in the received signal, such as subtracting an average of a block of received samples from each sample in the block. A distance metric, such as a sum of square differences, is computed between the DC compensated received signal and an ideal version of the received signal expected when reading the synchronization mark. The synchronization mark is detected if the distance metric satisfies predefined criteria. The ideal version of the received signal can optionally be processed to compensate for a DC bias in the synchronization mark. A search for the synchronization mark search can be limited to time cycles that match a known phase.

Abstract: An electrostatic transmission mechanism can be adopted for use in data media recorders such as printers, facsimile machines, or scanners to transport media. The invention has a feed roller with an electrostatic field generator located therein to generate static electricity on the surface of the feed roller to attract and transport media. The invention can eliminate the disadvantages of conventional transmission mechanisms such as crumpled paper resulting from the pressing of the feed rollers, star wheel tracks on the paper caused by the star wheels, etc.