Cirrus Logic Inc.

Broadcom Corporation

Infineon Technologies Ag

Stmicroelectronics Gmbh

Marvell International Limited

Infineon Technologies North America Corp.

Infineon Technolgies Na Corp.

William G Bliss

David E Reed

Razmik Karabed

Richard T Behrens

Trent O Dudley

James Wilson Rae

German S Feyh

Andrei Vityaev

Thomas V Souvignier

Christopher P Zook

David R Welland

Vasudevan Parthasarathy

John P Mead

Mark S Spurbeck

Jonathan James Ashley

Paul M Romano

Gregory Lee Silvus

Li Du

John S Wang

Stephen James Franck

William R Foland, Jr

Wael William Diab

Arthur Abnous

Sasan Cyrusian

Neal Glover

Yu Liao

Jerrell P Hein

Engling Yeo

Elmar Bach

Alan J Armstrong

Mark Chambers

Thomas Blon

David M Pietruszynski

Marvin L Vis

Kent D Anderson

Sriharsha Annadore

Sian She

Lisa Chaya Sundell

Tyson Tuttle

Heinrich J Stockmanns

Diwakar Vishakhadatta

Jerrel P Hein

Kaichi Zhang

Ronald Dane DeGroat

Heiner Stockmanns

Fritz Mistlberger

Jay Neil Livingston

James M Graba

Michael A Ruegg

Siegfried Hart

Howard H Sheerin

Matthias Driller

German Stefan Otto Feyh

German S O Feyh

Jim Graba

Richard T Behems

Richard T Beherns

Ulrich Huewels

Ali Najafi

Bahjat Zafer

Chung-Kal Chow

Christopher Lyle Painter

Dominik Margraf

Stephen J Franck

Michael Ruegg

James W Rae

Systems and methods for optical multi-path interference (MPI) compensation are provided. In an embodiment, a mean MPI signal representing a mean amplitude of the MPI in an input signal is generated and subtracted from a first estimate of transmitted amplitude of the input signal to generate a mean MPI compensated estimate of transmitted amplitude. The mean MPI compensated estimate of transmitted amplitude is sliced to generate a decision of transmitted amplitude of the input signal. The mean MPI signal can be generated using a mean MPI feedback loop or using an iterative feed-forward process. In another embodiment, mean MPI levels corresponding to respective transmitted intensity levels are generated and used to control slice levels of a slicer in order to compensate for MPI.

Compensation for optical multi-path interference

An asymmetric PHY pair for communicating over a point-to-point link is disclosed. The PHY pair is asymmetric in that the signal processing power used by one of the PHYs to communicate a unit of data over the link is made to be less than that of the other PHY. This asymmetry is accomplished not merely by reducing the signal processing power of one of the PHYs at the expense of the rate at which symbols can be communicated over the link, but by transferring the signal processing power from one of the PHYs to the other PHY so that the symbol rate can be substantially maintained as compared to the symbol rate of a symmetric PHY pair. The asymmetric PHY pair can be advantageously implemented in many different types of communication systems (i.e., in communication systems where one end is more congested and/or crowded than the other end).

Asymmetric complexity PHYs to reduce power dissipation in point-to-point communication links

Embodiments enable quick PHY re-training when the link is restarted due an event such as EMI, for example. In particular, embodiments recognize that, in the case of such events as EMI, a substantial portion of the training process as prescribed in the standard can be bypassed during the link restart without affecting subsequent link performance. In particular, embodiments recognize that a substantial amount of previously learned link parameters may still be used after link restart, and thus eliminate the need to re-learn them thereby speeding up the link restart process. Further, embodiments recognize that the standard prescribed link start up procedure can be accelerated in the case of link restart by reducing standard prescribed periods for transitioning between states of the link start up process. Additionally, embodiments provide a mechanism that relies on the auxiliary bit (AUX) of LDPC coded user data frames to pre-emptively and dynamically notch out troublesome EMIs before they cause the link to fail.

PHY retraining

Embodiments for improving the Signal to Noise and Distortion (SINAD) ratio in Pulse Amplitude Modulation (PAM)-M optical intensity modulation systems, to enable higher data rate communications, are provided. Embodiments can be used to improve the linearity and reduce the distortion of electrical and electro-optics components (including optical modulators) in optical intensity modulation systems. Embodiments are well suited for use with PAM-M optical intensity modulators, such as segmented Vertical Cavity Surface Emitting Laser (WSEL) and segmented Mach-Zehnder Modulator (MZM), for example.

Linearization of optical intensity modulation systems

Systems that allow for DFE functionality to be eliminated from the receiver side of a communication system and for a DFE-like functionality to be implemented instead at the transmitter side of the communication system are provided. By removing the DFE functionality from the receiver side, error propagation can be eliminated at the receiver and receiver complexity can be reduced drastically. At the transmitter side, the DFE-like functionality provides the same DFE benefits, and with the transmitter environment being noise-free, no errors can occur due noise boosting, for example. The DFE-like functionality at the transmitter side can be implemented using non-linear (recursive or feed-forward) pre-coders or a combination of non-linear pre-coders and linear filters, which can be configured to invert a net communication channel between the transmitter and the receiver. Embodiments particularly suitable for fiber optic channels and server backplane channels are also provided.

Generalized transmit pre-coding for optical and backplane channels

Systems and methods are provided for common mode testing for a system using an Ethernet subsystem. The Ethernet subsystem generates test signals that can be introduced at various points in the system to detect the effect of noise introduced by various elements of the system. By introducing test signals at various points in a system, common mode noise introduced into the system can be more accurately determined.

BASE-T common mode testing in an Ethernet subsystem

In conventional Backplane Ethernet systems, data is transmitted over two pairs of copper traces in one direction using a PAM-2 scheme and a baud rate of 10.3125 GHz, giving an effective bit rate of 10.3125 Gbps. The rate at which data can be transmitted in Backplane Ethernet systems, while still being reliably received, is typically limited by ISI caused by the dispersive nature of the copper traces, frequency dependent transmission losses caused primarily by skin effect and dielectric loss of the copper traces, and cross-talk from adjacent communication lines. The present invention is directed to systems for overcoming these and other signal impairments to achieve speeds up to, and beyond, twice the conventional 10 Gbps limit associated with Backplane Ethernet systems.

Systems for high-speed backplane applications using pre-coding

The present disclosure is directed to systems for achieving speeds up to, and beyond, twice the conventional 10 Gbps limit associated with Backplane Ethernet systems. In one example, the system is a transmitter that includes a FEC encoder configured to generate and append redundant symbols to the input data stream to provide a FEC encoded data stream, a serial-to-parallel module configured to de-serialize the FEC encoded data stream and distribute the FEC encoded data stream over parallel FEC encoded data streams with at least one of the redundant symbols generated by the FEC encoder generated based on data sent over two or more of the parallel FEC encoded data streams, and a line code encoder configured to modulate one of the parallel FEC encoded data streams.

Systems for high-speed backplane applications using FEC encoding

Super block error correction code (ECC) adaptable to communication systems including hard disk drives (HDDs) and other memory storage devices. A means is presented by which a number of blocks of information can be organized, with a degree of ECC provided thereto, and transmitted via a signal into a communication channel. In some instances, the communication channel is coupled to a storage media as in the context of an HDD, and information is written to and read from the storage media via this communication channel (e.g., 'read channel'). This means is particularly well suited to applications that provide large amounts of data via any one transmission (e.g., DVR/PVR (Digital/Personal Video Recorder)). A redundant block is generated using the information of each of a number of information blocks thereby provided extra ECC on a large portion of data, and that redundant block also undergoes ECC encoding.

Super block error correction code (ECC) adaptable to communication systems including hard disk drives (HDDs) and other memory storage devices

A servo writer includes a servo data generation module that generates servo data corresponding to a plurality of servo wedges and a plurality of tracks of a disk, the servo data including track identification data that is repetition coded. A servo write module writes the servo data on the disk.

Magnetic disk drive, servo writer, self-servo writer and methods for use therewith

Sliding block traceback decoding of block codes. Block by block basis decoding is performed in which a single block, and its corresponding overlap portion, are processed during a given time. The traceback saves a record of decision (e.g., among possible trellis branches between various trellis stages) and constructs only the surviving paths through each individual block. Since only one block (by also employing its corresponding overlap portion) is decoded per time, the traceback through the coded block signal is short. One block of the coded block signal is decoded at a time, and certain resulting information (e.g., bit estimates and/or states) of a first decoded block can be leveraged when decoding a second/adjacent block.

Sliding block traceback decoding of block codes

A write channel includes a pre-encoding module that encodes write data to produce pre-encoded data. An error correcting code (ECC) module generates ECC data based on the pre-encoded data. A post-encoding module encodes the ECC data to produce post-encoded data. A combining module combines the pre-encoded data and the post-encoded data for writing to the storage medium.

Read/write channel coding and methods for use therewith

Growing community of inventors

Thornton, CO, United States of America

William G Bliss