Patent application number | Description | Published |
20090296804 | Method and System for Near Optimal Iterative Detection of the 2-Dimensional ISI Channel - A method and system for decoding data received from a channel experiencing two-dimensional inter-symbol interference, as well as systems implementing such a decoding method and system, are disclosed. The method includes an iterative multi-strip equalization method that receives a plurality of channel values associated with a plurality of locations in a plurality of rows of a matrix, computes initial probability values based upon those channel values, applies a BCJR algorithm to symbol probability values based upon bands of rows of the initial probability values, and resolves the results of applying the BCJR algorithm to arrive at a plurality of bands of rows of revised probability values, which are subsequently combined/substituted with one another. The process iteratively repeats until the revised probability values attain a sufficient degree of convergence. By utilizing data from overlapping bands to perform the BCJR algorithm, ISI in both dimensions is addressed. | 12-03-2009 |
20110075569 | OBTAINING PARAMETERS FOR MINIMIZING AN ERROR EVENT PROBABILITY - A set of one or more receiver parameters is adjusted. It is determined whether to adjust the set of receiver parameters. In the event it is determined to adjust the set of receiver parameters, a new set of values is generated for the set of receiver parameters using a cost function (where the cost function does not assume a noise signal in a receive signal to have a particular statistical distribution) and the set of receiver parameters is changed to have the new set of values. | 03-31-2011 |
20110075779 | PREAMBLE ACQUISITION WITHOUT SECOND ORDER TIMING LOOPS - A clock is adjusted by obtaining a first plurality of samples and a second plurality of samples associated with a preamble portion of a data packet. The first plurality of samples and the second plurality of samples are sampled using a clock. A first intermediate value is determined based at least in part on the first plurality of samples and a second intermediate value is determined based at least in part on the second plurality of samples. An ending value associated with an end of the preamble portion is determined based at least in part on the first intermediate value and the second intermediate value. The clock is adjusted based at least in part on the ending value without use of a second order timing loop. | 03-31-2011 |
20110080939 | BASELINE WANDER COMPENSATION FOR PERPENDICULAR RECORDING - A tail estimate signal which includes noise associated with baseline wander is generated. The tail estimate signal is generated by processing an input signal using a detector to obtain one or more decisions. Using the one or more decisions, the tail estimate signal is generated. The tail estimate signal is removed from the input signal. | 04-07-2011 |
20110096433 | DECOUPLING MAGNETO-RESISTIVE ASYMMETRY AND OFFSET LOOPS - Signal correction is performed by determining an offset error based at least in part on a first portion of a signal within a first amplitude range. The offset error is associated with error due to offset in the signal. An signal error, associated with error due to offset and magneto-resistive asymmetry (MRA) in the signal, is determined based at least in part on a second portion of the signal within a second amplitude range; the second amplitude range does not overlap with the first amplitude range. An MRA error is determined by removing the offset error from the signal error and the MRA error is removed from the signal. | 04-28-2011 |
20120076196 | DECISION DIRECTED TIMING RECOVERY USING MULTI-PHASE DETECTION - A set of one or more samples is received. Using a first signal processor associated with a first phase offset, a first decision and a first error value are generated using the set of samples. Using a second signal processor associated with a second phase offset, a second decision and a second error value are generated using the set of samples. This includes interpolating the set of samples to obtain a set of interpolated samples at the second phase offset and generating the second decision and the second error value using the set of interpolated samples at the second phase offset. A selection associated with the first decision and the second decision is made based at least in part on the first error value and the second error value. | 03-29-2012 |
20120105994 | INTER-TRACK INTERFERENCE CANCELATION FOR SHINGLED MAGNETIC RECORDING - Inter-track interference cancelation is disclosed, including: receiving an input sequence of samples associated with a track on magnetic storage; using a processor to generate inter-track interference (ITI) data associated with a first side track including by performing a correlation between the input sequence of samples and a sequence of data associated with the first side track. | 05-03-2012 |
20120117414 | PREAMBLE ACQUISITION WITHOUT SECOND ORDER TIMING LOOPS - A clock is adjusted by obtaining a first plurality of samples and a second plurality of samples associated with a preamble portion of a data packet. The first plurality of samples and the second plurality of samples are sampled using a clock. A first intermediate value is determined based at least in part on the first plurality of samples and a second intermediate value is determined based at least in part on the second plurality of samples. An ending value associated with an end of the preamble portion is determined based at least in part on the first intermediate value and the second intermediate value. The clock is adjusted based at least in part on the ending value without use of a second order timing loop. | 05-10-2012 |
20120127799 | WRITE-PRECOMPENSATION AND VARIABLE WRITE BACKOFF - A technique for writing data is disclosed. The technique includes estimating an amount of additional voltage on a victim cell of a solid-state storage device caused by writing to one or more other cells in the solid-state storage device, determining a modified write value for the victim cell based at least in part on a desired value for the victim cell and the estimated amount of additional voltage, and writing the modified write value to the victim cell. | 05-24-2012 |
20140149649 | MEASURE OF HEALTH FOR WRITING TO LOCATIONS IN FLASH - For each of a plurality of locations in flash memory, a number of pulses required to change a value stored in that location is obtained. From the plurality of locations, a location to write to is selected using the obtained number of pulses. The selected location is written to. | 05-29-2014 |
20140189458 | SOFT INPUT, SOFT OUPUT MAPPERS AND DEMAPPERS FOR BLOCK CODES - A codebook which includes a plurality of messages and a plurality of codewords, a specified codeword bit value, and a specified message bit value are obtained. The LLR for bit ci in a codeword is generated, including by: identifying, from the codebook, those codewords where bit ci has the specified codeword bit value; for a message which corresponds to one of the codewords where bit ci has the specified codeword bit value, identifying those bits which have the specified message bit value; and summing one or more LLR values which correspond to those bits, in the message which corresponds to one of the codewords where bit ci has the specified codeword bit value, which have the specified message bit value. | 07-03-2014 |
20140191887 | MTR AND RLL CODE DESIGN AND ENCODER AND DECODER - An array f(n) is received for n=1, . . . , N where N is a length of a codeword. An array g(n) is received for n=1, . . . , N where N is a length of a codeword. Input data is encoded to satisfy an MTR constraint and a RLL constraint using the array f(n) and the array g(n). | 07-10-2014 |
20140192434 | INTER-TRACK INTERFERENCE CANCELATION FOR SHINGLED MAGNETIC RECORDING - Inter-track interference cancelation is disclosed, including: receiving an input sequence of samples associated with a track on magnetic storage; using a processor to generate inter-track interference (ITI) data associated with a first side track including by performing a correlation between the input sequence of samples and a sequence of data associated with the first side track. | 07-10-2014 |