Patent application number | Description | Published |
20090044084 | Combined DC restoration double detection and loops - A method of double detection in a perpendicular magnetic read channel is disclosed. The method generally includes the steps of (A) generating an intermediate signal by performing a first detection on an input signal of the perpendicular read channel, the first detection having a first error rate, (B) generating a statistics signal based on the intermediate signal, the statistics signal conveying noise statistics that depend on data in the input signal and (C) generating an output signal by performing a second detection on the input signal using the noise statistics to reduce a second error rate of the second detection compared with the first error rate, wherein the first detection is independent of the second detection. | 02-12-2009 |
20100177419 | AGC Loop with Weighted Zero Forcing and LMS Error Sources and Methods for Using Such - Various embodiments of the present invention provide systems and methods for gain control. For example, some embodiments of the present invention provide variable gain control circuits. Such circuits include a zero forcing loop generating a zero forcing feedback and a least mean square loop generating a least mean square feedback. An error quantization circuit generates a hybrid feedback based upon a threshold condition using the zero forcing feedback and the least mean square feedback. A variable gain amplifier is at least in part controlled by a derivative of the hybrid feedback. | 07-15-2010 |
20100287420 | Systems and Methods for Adaptive Equalization in Recording Channels - Various embodiments of the present invention provide systems and methods for performing adaptive equalization. For example, various embodiments of the present invention provide methods for adaptive equalization that include providing a data processing system with an equalizer circuit ( | 11-11-2010 |
20120063022 | Systems and Methods for Inter-track Interference Compensation - Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is discussed that includes: a data buffer, an inter-track interference response circuit, and an inter-track interference signal estimator circuit. The data buffer is operable to store a previous track data set. The inter-track interference response circuit is operable to estimate an inter-track interference response from the previous track data set based at least in part on the previous track data set and a current track data set. The inter-track interference signal estimator circuit is operable to calculate an inter-track interference from the previous track data set based at least in part on the previous track data set and the inter-track interference response from the previous track data set. | 03-15-2012 |
20120063023 | Systems and Methods for Block-wise Inter-track Interference Compensation - Various embodiments of the present invention provide systems and methods for data processing. As an example, a block-wise data processing circuit is discussed that includes: a data buffer, an inter-track interference response circuit, and an inter-track interference signal estimator circuit. The data buffer is operable to store a previous track data set corresponding to a block. The inter-track interference response circuit is operable to estimate an inter-track interference response from the previous track data set across the block based at least in part on the previous track data set and a current track data set. The inter-track interference signal estimator circuit is operable to calculate an inter-track interference from the previous track data set across the block based at least in part on the previous track data set and the inter-track interference response from the previous track data set. | 03-15-2012 |
20120063024 | Systems and Methods for Handling Sector Gaps in Inter-track Interference Compensation - Various embodiments of the present invention provide systems and methods for data processing. As an example, a data processing circuit is discussed that includes an inter-track interference determination circuit operable to calculate an inter-track interference from a previous track data set based at least in part on the previous track data set and a current track data set. The previous track data set includes a gap. A portion of the data in the previous track data set corresponds to a previous track on a storage medium, and the data in the previous track data set corresponding to the gap corresponds to a track preceding a previous track. | 03-15-2012 |
20130021689 | STORAGE MEDIA INTER-TRACK INTERFERENCE CANCELLATION - Described embodiments provide a method of cancelling inter-track interference (ITI) from one or more sectors read from a desired track of a storage medium. A read channel reads sectors in a desired track of the storage medium. A decoder of the read channel decodes the read sectors, and if the read sectors are incorrectly recovered from the storage medium, selected sectors of a first adjacent track and a second adjacent track are read. An ITI canceller of the read channel estimates ITI in the read sectors of the desired track corresponding to the selected sectors of each adjacent track and subtracts the estimated ITI of each adjacent track from the data for the sectors of the desired track, providing updated sector data. The ITI cancelled data is replayed to the decoder, which decodes the ITT cancelled data and provides the decoded ITI cancelled data as output of the read channel. | 01-24-2013 |
20130070362 | ENERGY-BASED INTER-TRACK INTERFERENCE CANCELLATION - Described embodiments cancel inter-track interference (ITI) from one or more sectors read from a desired track of a storage medium. A read channel reads one or more sectors in the desired track and generates one or more groups of sample values corresponding to each of the sectors. An ITI canceller estimates an ITI response and an ITI signal for each sample value corresponding to (i) a next adjacent track and (ii) a previous adjacent track. If the estimated ITI response of the previous adjacent track reaches a predetermined threshold, the ITI canceller subtracts the estimated ITI signal corresponding to the previous adjacent track from each associated sample value of the desired track. If the estimated ITI response of the next adjacent track reaches a predetermined threshold, the ITI canceller subtracts the estimated ITI signal corresponding to the next adjacent track from each associated sample value of the desired track. | 03-21-2013 |
20130223199 | STORAGE MEDIA INTER-TRACK INTERFERENCE CANCELLATION - Described embodiments provide a method of cancelling inter-track interference (ITI) from one or more sectors read from a desired track of a storage medium. A read channel reads sectors in a desired track of the storage medium. An iterative decoder of the read channel decodes the read sectors, and if the read sectors are incorrectly recovered from the storage medium, selected sectors of a first adjacent track are read. An ITI canceller of the read channel estimates ITI in the read sectors of the desired track corresponding to the selected sectors of the adjacent track and subtracts the estimated ITI of the adjacent track from the data for the sectors of the desired track, providing updated sector data. The ITI cancelled data is replayed to the iterative decoder, which decodes the ITI cancelled data and provides the decoded ITI cancelled data as output data of the read channel. | 08-29-2013 |
20130286498 | INTER-TRACK INTERFERENCE MITIGATION IN MAGNETIC RECORDING SYSTEMS USING AVERAGED VALUES - Hardware-based methods and apparatus are provided for inter-track interference mitigation in magnetic recording systems using averaged values. Inter-track interference (ITI) is mitigated in a magnetic recording system by obtaining ITI cancellation data; and providing the ITI cancellation data for ITI mitigation, wherein the ITI mitigation is performed in combination with an averaging procedure for one or more of ITI mitigation of averaged data and averaging of ITI mitigated data. The sector is optionally decoded using the ITI mitigated samples. Samples for one or more side track sectors can also be averaged. The averaged side track samples can be provided as ITI cancellation data for ITI mitigation. The averaging procedure optionally applies a scaling factor to each read value. | 10-31-2013 |
20140153126 | Systems and Methods for Old Data Inter-track Interference Compensation - Systems and methods for data processing, and more particularly to estimating or calculating interference between tracks on a storage medium. | 06-05-2014 |
20140233129 | NOISE PREDICTIVE FILTER ADAPTATION FOR INTER-TRACK INTERFERENCE CANCELLATION - Systems, methods, devices, circuits for data processing, and more particularly to systems and methods for adapting noise predictive filters for inter-track interference cancellation in a data processing system. | 08-21-2014 |
20140286385 | Systems and Methods for Multi-Dimensional Signal Equalization - Embodiments are related to systems and methods for data processing, and more particularly to systems and methods for equalizing a data signal. | 09-25-2014 |
20150015984 | Storage Media Inter-Track interference Cancellation - Described embodiments provide a method of cancelling inter-track interference (ITI) from one or more sectors read from a desired track of a storage medium. A read channel reads sectors in a desired track of the storage medium. A decoder of the read channel decodes the read sectors, and if the read sectors are incorrectly recovered from the storage medium, selected sectors of a first adjacent track and a second adjacent track are read. An ITI canceller of the read channel estimates ITI in the read sectors of the desired track corresponding to the selected sectors of each adjacent track and subtracts the estimated ITI of each adjacent track from the data for the sectors of the desired track, providing updated sector data. The ITI cancelled data is replayed to the decoder, Which decodes the ITT cancelled data and provides the decoded ITI cancelled data as output of the read channel. | 01-15-2015 |