Lsi Logic Corporation

Calimetrics, Inc.

Lsi Corporation

Ohio University

Yung-Cheng Lo

David C Lee

Steven Russel Spielman

Judith C Powelson

David Warland

Jonathan A Zingman

Yi Ling

John L Fan

Terrence L Wong

Richard L Martin

Laura L McPheters

Ting Zhou

Steven W McLaughlin

Ian E Harvey

Christine Pepin

Alan Ray Lindsey

Steve W McLaughlin

Frank A Alder

Xiangyu Song

Steven E McLaughlin

Jeffrey C Dill

Sergio R Lopez-Permouth

A system and method are disclosed for providing a gain control signal for a multilevel read signal. In one embodiment, maximum automatic gain control marks are periodically inserted amongst a series of data fields. The automatic gain control marks include a series of high level marks such that the maximum signal detected in the interior portion of each maximum automatic gain control mark is not reduced by intersymbol interference. Minimum automatic gain control marks are also periodically inserted amongst a series of data fields. The automatic gain control marks include a series of high level marks such that the maximum signal detected in the interior portion of each minimum automatic gain control mark is not reduced by intersymbol interference. In another embodiment, multilevel signals are encoded to facilitate automatic gain control. The effect of a plurality of candidate merge symbols on the residual running total power associated with a current data block is determined. A preferred merge symbol is selected based on a residual running total power minimization criteria. The preferred merge symbol is added to the current data block.

Digital automatic gain control of a multilevel optical disc read signal

A system and method are disclosed for reading a multilevel signal from an optical disc. The method includes reading a raw analog data signal from a disc using an optical detector and adjusting the amplitude of the raw analog data signal. A timing signal is recovered from the amplitude adjusted analog data signal and correction is made for amplitude modulation of the raw analog data signal by processing the raw analog data signal and the timing signal.

Method and apparatus for reading and writing a multilevel signal from an optical disc oscillators

A method of building systematically a multi-dimensional (n, D, L) circular trellis coded modulation (CTCM) encoder with properties of optimal energy efficiency, strong tail biting and maximum minimum distance (d) of trellis paths is disclosed. In addition, a communication system for use in a power limited channel application is disclosed comprising a circular trellis coded modulation (CTCM) encoder with permuted state structure for encoding based on a circular trellis path associated with a sequence of digital information bits and a set of simplexes identified for the path from a multi-dimensional signal constellation; a transmitter coupled to said CTCM encoder for transmitting said sequence of channel symbols over said channel; a receiver for receiving a transmission from said transmitter including said sequence of channel symbols and any noise induced therein; and a CTCM decoder coupled to said receiver for decoding the received transmission without knowledge of the starting state of the circular trellis path of the CTCM encoder to recover the sequence of information bits. Apparatus and methods of encoding and decoding are also disclosed utilizing a combination of circular trellis-coded modulation with permuted state structure and simplex signal constellation techniques for use in the digital communication system.

Apparatus and method of CTCM encoding and decoding for a digital communication system

Methods and systems for write compensation for optimizing the performance of a data storage or communication channel are disclosed. In one embodiment, a method comprises determining channel sensitivity to modifications in write signal parameters, detecting systematic errors in a read signal recovered from data written with a first set of write parameters, and adjusting the write signal parameters by an amount determined from the channel sensitivity such that the systematic errors are reduced when data are written with the adjusted write parameters.

Write compensation for data storage and communication systems

Method and apparatus for reading and writing a multilevel signal from an optical disc

A system and method are disclosed for writing a multilevel data sequence to a storage medium so that a read signal generated by reading the multilevel data sequence from the storage medium will have reduced low frequency content is described. The method includes evaluating the effect of a plurality of candidate merge symbols on an RDS of the read signal. A preferred merge symbol is selected from among the plurality of candidate merge symbols based on the effect of the preferred merge symbol on an RDS of the read signal. The preferred merge symbol is added to the multilevel data sequence so that the RDS of the read signal is controlled.

DC control of a multilevel signal

A method is disclosed for compensating for intersymbol interference on an optical disc. The method includes measuring an intersymbol linear transfer function. The intersymbol linear transfer function substantially describes a linear portion of the effect of intersymbol interference on an optically detected read signal from an optical disc. A partial response target frequency response is divided by the intersymbol linear transfer function to obtain a linear equalization filter response. A read signal from the optical disc is convolved with the linear equalization filter response. This results in the read signal being equalized and containing a controlled partial-response target intersymbol interference. There is also disclosed a method of compensating utilizing a decision feedback equalizer where the target frequency response is either a partial-response or a zero-forcing response.

Method for providing improved equalization for the reading of marks on optical data-storage media

Growing community of inventors

San Leandro, CA, United States of America

Yung-Cheng Lo