Quellan, Inc.

The United States of America As Represented by the United States

Sandia Corporation

National Technology & Engineering Solutions of Sandia, LLC

The United States of America As Represented by the Department of Energy

Quelian, Inc.

Vincent Mark Hietala

Andrew Joo Kim

Jon S Martens

Gregory A Vawter

Stephen E Ralph

Michael Gerald Vrazel

Sanjay Bajekal

Gert K Hohenwarter

Thomas A Plut

Joy Laskar

David Samuel Ginley

Stanley H Kravitz

Thomas E Zipperian

Edward Gebara

Chris P Tigges

Sungyong Jung

Roy H Olsson

James G Fleming

Harold L Stalford

G Allen Vawter

John P Hohimer

David S Ginley

Carol Fleming, Legal Representative

Alan Mar

Neil R Sorensen

John C Zolper

Susan Leslie Hietala

Chris P Tiggers

Joy Lasker

A spur cancelling, electromechanical filter includes a first resonator having a first resonant frequency and one or more first spurious responses, and it also includes, electrically connected to the first resonator, a second resonator having a second resonant frequency and one or more second spurious responses. The first and second resonant frequencies are approximately identical, but the first resonator is physically non-identical to the second resonator. The difference between the resonators makes the respective spurious responses different. This allows for filters constructed from a cascade of these resonators to exhibit reduced spurious responses.

Attenuation of spurious responses in electromechanical filters

Processing a signal comprising signal distortions with filters. The filters comprise a first filter configured to a first time scale to compensate for signal distortions within respective symbols of the signal and a second filter configured to a second time scale to compensate for signal distortions among symbols of the signal. A probability estimate is produced based on an output of at least one of the first and second filters. At least one of the first and second time scales is adjusted according to the probability estimate.

Adaptive noise filtering and equalization

A Signal Conditioning Filter (SCF) and a Signal Integrity Unit (SIU) address the coupled problem of equalization and noise filtering in order to improve signal fidelity for decoding. Specifically, a received signal can be filtered in a manner to optimize the signal fidelity even in the presence of both significant (large magnitudes of) ISI and noise. The present invention can provide an adaptive method that continuously monitors a signal fidelity measure. Monitoring the fidelity of a multilevel signal can be performed by external means such as by the SIU. A received signal y(t) can be 'conditioned' by application of a filter with an electronically adjustable impulse response g(t). A resulting output z(t) can then be interrogated to characterize the quality of the conditioned signal. This fidelity measure q(t) can be used to adjust the filter response to maximize the fidelity measure of the conditioned signal.

Adaptive noise filtering and equalization for optimal high speed multilevel signal decoding

A microelectromechanical tunable inductor is formed from a pair of substantially-identically-sized coils arranged side by side and coiled up about a central axis which is parallel to a supporting substrate. An in-plane stress gradient is responsible for coiling up the coils which. The inductance provided by the tunable inductor can be electrostatically changed either continuously or in discrete steps using electrodes on the substrate and on each coil. The tunable inductor can be formed with processes which are compatible with conventional IC fabrication so that, in some cases, the tunable inductor can be formed on a semiconductor substrate alongside or on top of an IC.

Microelectromechanical tunable inductor

A multilevel optical receiver can comprise a plurality of comparators that generally correspond with the number of levels in a multilevel data stream. Each comparator can be individually controlled and fed a decision threshold in order to decode a multilevel signal. The multilevel optical receiver can generate a statistical characterization of the received symbols in the form of a marginal cumulative distribution function (CDF) or probability density function (pdf). This characterization can be used to produce a set of &#x3b5;-support estimates from which conditional pdfs are derived for each of the transmission symbols. These conditional pdfs may then be used to determine decision thresholds for decoding the received signal. The conditional pdfs may further be used to continuously estimate the fidelity or error rate of the received signal without the transmission of a testing sequence. The &#x3b5;-supports may further be used to automatically control the gain on the receiver.

Method and system for decoding multilevel signals

Decreasing the average transmitted power in an optical fiber communication channel using multilevel amplitude modulation in conjunction with Pulse Position Modulation (PPM). This multilevel PPM method does not entail any tradeoff between decreased power per channel and channel bandwidth, enabling a lower average transmitted power compared to On/Off Keying (OOK) with no reduction in aggregate data rate. Therefore, multilevel PPM can be used in high-speed Dense Wavelength Division Multiplexed (DWDM) systems where the maximum number of channels is traditionally limited by nonlinear effects such as self-phase modulation (SPM), cross-phase modulation (XPM), four-wave mixing (FWM), stimulated Brillouin scattering (SBS), and stimulated Raman scattering (SRS). This modulation technique can enable an increased number of channels in DWDM systems, thereby increasing aggregate data rates within those systems.

Multilevel pulse position modulation for efficient fiber optic communication

Data throughput rates are increased in an optical fiber communication system without requiring replacement of the existing optical fiber in a link. Channel throughput is increased by upgrading the components and circuitry in the head and terminal of an optical fiber communication system link. Aggregate throughput in a fiber optic link is increased beyond the range of conventional Wavelength Division Multiplexed (WDM) upgrades, while precluding the necessity of replacing existing fiber plants. The increase in system throughput is achieved by using advanced modulation techniques to encode greater amounts of data into the transmitted spectrum of a channel, thereby increasing the spectral efficiency of each channel. This novel method of increasing transmission capacity by upgrading the head and terminal of the system to achieve greater spectral efficiency and hence throughput, alleviates the need to replace existing fiber plants. Spectrally efficient complex modulation techniques can be supported by interface circuits with an increased level of signal processing capability in order to both encode multiple bits into a transmitted symbol and decode the original data from the received symbols.

Increasing data throughput in optical fiber transmission systems

Clock recovery of a multi-level (ML) signal can be performed in a two-step process. First, the transitions within the ML signal can be detected by a novel transition detector (TD). And second, the output of the TD circuit can comprise a pseudo-non-return-to-zero (pNRZ) signal that can drive a conventional OOK clock recovery (CR) IC. The TD circuit can convert the edges of the ML signal into the pseudo-NRZ (pNRZ) signal. The TD circuit can capture as many transitions as possible to allow the conventional NRZ clock recovery (CR) chip to optimally perform. The TD circuit can differentiate the ML signal in order to detect the ML signal's transitions.

Multi-level signal clock recovery technique

A method for high speed communications uses an inventive Q-Gray code. The Q-Gray code simplifies the hardware needed to convert analog Q-Gray code signals to digital signals. An analog-to-digital converter can use a plurality of comparators for receiving the multilevel signal and a plurality of decoder blocks coupled to comparators for decoding the multilevel signal. Each decoder block can include an equal number of inputs. Specifically, each decoder block can also include a parity detector with an equal number of inputs. Each decoder block can also employ a bank of identical parity detectors relative to another decoder block. Each comparator of the analog to digital converter can have an individually or externally adjustable (or both) threshold level.

High-speed analog-to-digital converter using a unique gray code

A method and apparatus for measuring surface changes, such as mass uptake at various pressures, in a thin-film material, in particular porous membranes, using multiple differently-configured acoustic sensors.

Method and apparatus for measuring surface changes, in porous materials, using multiple differently-configured acoustic sensors

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Albuquerque, NM, United States of America

Vincent Mark Hietala