Cirrus Logic Inc.

Silicon Laboratories Inc.

Marvell International Limited

St-ericsson Sa

Broadcom Corporation

Lake Cherokee Hard Drive Technologies, LLC

Richard T Behrens

Trent O Dudley

G Tyson Tuttle

Neal Glover

Jeffrey William Scott

Donald A Kerth

Vishnu Shankar Srinivasan

G Diwakar Vishakhadatta

William G Bliss

Mark S Spurbeck

Alan J Armstrong

David R Welland

David E Reed

Kent D Anderson

Larry D King

Christopher P Zook

Tod Paulus

Bill R Foland

William R Foland, Jr

Caiyi Wang

Lysander Lim

Li Du

Tyson Tuttle

Augusto Manuel Marques

Paul M Romano

German S Feyh

Diwakar Vishakhadatta

Jerrel P Hein

Dan Bernard Kasha

Aslamali A Rafi

Gregory Takeo Uehara

James P Maligeorgos

Stephen Alan Turk

Marvin Leroy Vis

Wade Robert Gillham

Jing Liang

Mats Oberg

Russell Croman

Alan Armstrong

John J Schadegg

Samuel Rousselin

Lisa Chaya Sundell

Charles J Duey

William L Witt

Eric R Garlepp

Renee E Wallerius

Laura Droege Shellhamer

Iuri Mehr

A method of operating or calibrating a storage device having a storage medium platter includes writing servo data to the storage medium platter, where the servo data include, for each track on the storage medium platter, a servo sync mark, and a repeating pattern. For each pair of adjacent tracks on the storage medium platter, the repeating patterns, which may be orthogonal, are compared to determine relative phase of the repeating patterns on adjacent tracks. The relative phase for each pair of adjacent tracks is recorded. In another calibration method, first and second repeating patterns may compared to determine whether relative phase of the first and second repeating patterns exceeds a threshold, in which case the second servo data are erased, new second servo data are written, and the comparing and erasing are repeated until the relative phase of the first and second repeating patterns is less than the threshold.

Method and apparatus for determining radial incoherence between servo tracks

A method of writing data using more than one write head to write to more than one storage media platter surface of a storage device, where one actuator in the storage device controls positions of all of the write heads, includes controlling the position of one of the write heads to a selected radial track location, writing simultaneously to storage media of the storage device at the selected radial track location using a plurality of the write heads, and, during the writing at the selected radial track location, reading servo data using respective read heads associated with each respective one of the plurality of write heads and recording the radial position of the respective heads for the selected radial track location. During reading, the recorded head position for the track of the platter surface to be read is determined, and the read head is served to the recorded head position.

Method and apparatus for writing to and reading from multiple drive heads

Radio-frequency (RF) apparatus includes receiver analog circuitry that receives an RF signal and provides at least one digital signal to receiver digital circuitry that functions in cooperation with the receiver analog circuitry. The receiver analog circuitry and the receiver digital circuitry are partitioned so that interference effects between the receiver analog circuitry and the receiver digital circuitry tend to be reduced.

Partitioned radio-frequency apparatus and associated methods

Systems and methods for reading data from a magnetic medium are provided. A system for reading data from a magnetic medium includes an electromagnetic head array, where the electromagnetic head array includes a plurality of read sensors. Each read sensor of the plurality of read sensors is configured to sense a magnetic field of the magnetic medium and to generate a signal based on the magnetic field. Circuitry is configured to combine the signals of the plurality of read sensors to generate a resulting signal. The resulting signal defines an effective read width of the electromagnetic head array, where the effective read width is narrower than a read width of any of the plurality of read sensors.

System and method for reading data from a magnetic medium by utilizing plural read sensors which define an effective read width

A radio-frequency apparatus includes an integrated circuit. The integrated circuit includes receiver analog circuitry, receiver digital circuitry, a digital-to-analog converter, and a signal selector. The receiver analog circuitry receives radio-frequency signals, and provides a first digital signal. The receiver digital circuitry receives the first digital signal, and provides a second digital signal. The digital-to-analog converter converts the second digital signal into a first analog signal. The signal selector receives the second digital signal and the first analog signal, and selectively provides one of the second digital signal and the first analog signal as an output signal of the integrated circuit.

Radio-frequency apparatus and associated methods

A radio-frequency (RF) receiver includes a receiver analog circuitry and a receiver digital circuitry. The receiver analog circuitry resides within a first integrated circuit and the receiver digital circuitry resides within a second integrated circuit. The second integrated circuit couples to the first integrated circuit via a one-bit digital interface. The receiver analog circuitry receives an RF signal and processes the received RF signal to generate a digital signal. The receiver analog circuitry provides the digital signal to the receiver digital circuitry. The receiver digital circuitry includes a digital down-converter circuitry that mixes the digital signal with an intermediate frequency (IF) local oscillator (LO) signal to generate a digital down-converted signal. The receiver digital circuitry also includes a digital filter circuitry that filters the digital down-converted signal to generate a filtered digital signal.

Digital architecture for radio-frequency apparatus and associated methods

Receiver architectures and related methods are disclosed for high definition (HD) and digital radio FM broadcast receivers. The radio receiver architectures are configured to utilize multiple analog-to-digital converters (ADCs) to handle the digital radio spectrum and can be configured to modify a target IF frequencies depending upon the mode of operation of the receiver. For example, the receiver can include an analog FM reception mode and a digital FM reception mode for which different down-conversions are used for the same analog-plus-digital audio broadcast channel. If desired, the radio broadcast receivers disclosed can be configured so that they only receive digital FM radio content, for example, if the analog FM broadcast was of no interest and/or if the broadcast was all digital.

Receiver architectures for digital radio broadcasts and associated methods

A wireless communication system is provided that detects a frequency burst (FB) through analysis of the autocorrelation function of received signals. The system can accommodate the relatively large frequency offsets that are associated with less expensive reference frequency crystals. The system employs a multi-mode filter including an FB filter and a channelization filter. In one embodiment, the FB filter is employed until an FB is located and then, once the FB is located, the channelization filter is employed to receive signals.

Wireless communication system and method with frequency burst acquisition feature using autocorrelation

A synchronous read channel having a single chip integrated circuit digital portion which provides digital gain control, timing recovery, equalization, digital peak detection, sequence detection, RLL(1,7) encoding and decoding, error-tolerant synchronization and channel quality measurement is disclosed. The integrated circuit accommodates both center sampling and side sampling, and has a high degree of programmability of various pulse shaping and recovery parameters and the ability to provide decoded data using sequence detection or digital peak detection. These characteristics, together with the error-tolerant sync mark detection and the ability to recover data when the sync mark is obliterated, allow a wide variety of retry and recovery strategies to maximize the possibility of data recovery. Various embodiments, including an embodiment incorporating the analog functions as well as the primary digital functions of the read channel in a single integrated circuit, and preferred embodiments utilizing a reduced complexity, programmable modified Viterbi detector supporting a broad class of partial response channels are disclosed.

Synchronous read channel

A wireless communication system is provided that detects a frequency burst (FB) through analysis of the autocorrelation function of received signals. The system can accommodate the relatively large frequency offsets that are associated with less expensive reference frequency crystals. In one embodiment, the system includes FB search hardware that operates in two modes, namely an FB location mode with narrowband interference (e.g. CW or continuous wave) detection and an FB location mode without such narrowband interference detection, depending on whether a CW signal (carrier or other narrowband interferer) is present or not.

Wireless communication system and method with frequency burst acquisition feature using autocorrelation and narrowband interference detection

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Louisville, CO, United States of America

Richard T Behrens