Pmc-Sierra, Inc.

Pmc-Sierra US, Inc.

Cold Bore Technology Inc.

The University of British Columbia

Microsemi Storage Solutions (u.s.), Inc.

Microsemi Storage Solutions, Inc.

William Dean Warner

Anthony Eugene Zortea

Paul V Yee

Andrew S Wright

Ognjen B Katic

Aryan Saed

Soon Sun Shin

Matthew Johan Zieleman

William Michael Lye

Bartholomeus T W Klijsen

Graeme Barclay Boyd

Derek J W Ho

Richard Edmund Ryan

Nicolai Calin Pacurari

Craig Anthony Bergmann

Xiaofeng Wang

Cybil S Leung

Hector Arturo Nunez

Clarence K L Tam

Jim Guziak

Jeremy Benson

Methods determine a state of a well and comprise: receiving a set of well operations data comprising at least some measured well operations data; determining the occurrence of a well operations event based on the received data; evaluating one or more possible state transitions from a current well operations state to one or more possible new well operations states, the current state and the possible new states selected from a configurable plurality of well operations states, wherein evaluating the one or more possible state transitions is based on the current state, the determined event and the received data and wherein evaluating the one or more possible state transitions comprises determining a confidence level associated with each of the possible new states; and determining one of the possible new states to be a new predicted well operations state according to whichever possible new state has a highest confidence level.

Automated detection of plug and perforate completions, wellheads and wellsite operation status

A system detects an acoustic-wave-producing downhole event associated with a pipe at an uphole location in the presence of surface noise. The system comprises: a first plurality of acoustic sensors located a first axial position along the pipe and oriented symmetrically about the pipe axis; and a second plurality of acoustic sensors located a second axial position along the pipe and oriented symmetrically about the pipe axis, the second axial position spaced apart from the first axial position. A processor is connected to receive the signals from the first and second pluralities of sensors and configured to process the sensor signals to thereby produce an output signal. The processor is configured to adjust the digital processing, based on the sensor signals, to minimize a contribution of the surface noise to the output signal.

Adaptive noise reduction for event monitoring during hydraulic fracturing operations

A communication method is provided for a communication system comprising a transmitter and a receiver. The method involves communicating data from the transmitter to the receiver over a banded communication channel. The method comprises: applying a forward error correction, FEC, code to data to be transmitted to obtain FEC-encoded data; assigning the FEC-encoded data into a plurality of sub-channels; modulating the data from each of the plurality of sub-channels into a corresponding one of a plurality of sub-bands, the plurality of sub-bands having spaced apart center frequencies; and concurrently transmitting the data from the plurality of sub-bands onto a banded communication channel, the banded communication channel comprising one or more pass-bands and one or more stop-bands.

Methods and systems for forward error correction for measurement while drilling (MWD) communication systems

A receiver equalizer that provides improved jitter tolerance relative to common adaptation mechanisms and that also provides inter-symbol interference. Improved jitter tolerance is an important benefit for SERDES receivers as tolerance to Sinusoidal Jitter is an important performance metric specified in most industry standards.

Method for reducing jitter in receivers

Apparatus and methods reduce channel-dependent phase detector offset and/or gain errors. A conventional Mueller-Muller phase detector places a main cursor at the midpoint of a pre-cursor and a post-cursor. However, for example, when the impulse response of an associated transmission line is not symmetric, the main cursor can be misaligned by conventional Mueller-Muller techniques. By providing a replica clock and data recovery path, trial and error experiments on the phase detector offset and/or gain can be performed, and relatively good values found for the phase detector offset and/or gain without disturbing the reception of data by the phase detector that is being used to receive data. These settings can then be used by the phase detector that is being used to receive data, which can improve the bit error rate of the phase detector.

Parallel replica CDR to correct offset and gain in a baud rate sampling phase detector

Apparatus and methods calibrate and control detector gain in a Mueller-Muller timing detector. A Mueller-Muller circuit obtains timing information for a received signal in which the receiving device samples the signal once per baud period.

Gain calibration for a timing error detector

A SerDes receiver comprising: an input for receiving a signal, the signal having a baud rate; an Analog Finite Impulse Response equalizer (AFIR) for equalizing the received signal, the AFIR comprising: a pre-cursor tap having a pre-cursor coefficient; a cursor tap having a cursor coefficient, the cursor coefficient being constrained to a non-negative value; and a post-cursor tap having a post-cursor coefficient; an adaptation block coupled to the AFIR, the adaptation block configured to adjust the pre-cursor coefficient and the post-cursor coefficient based on the received signal, the adaptation block further being configured to constrain the values of the pre-cursor and post-cursor coefficients to be non-positive.

Analog finite impulse response adaptation method and apparatus

Apparatus and methods mitigate a problem of equalizing communications signals that have been distorted by severe non-linearities such as clipping or harsh compression. For example, severe non-linearity occurs when signal compression or signal clipping occurs at rates above 20% of the data transmission interval. Severe non-linearities may significantly reduce system performance. Disclosed techniques selectively apply DSP equalization based on the detection of non-linearity for a present sample or one or more samples prior to the present sample. These techniques can be implemented in relatively low-cost high-speed SerDes designs to improve eye openings and reduce sensitivity to InterSymbol Interference (ISI) and to improve bit error rate (BER).

Equalizer for heavily clipped or compressed communications signals

Methods and circuits for equalizing a linear response in an observation path of a digital pre-distorter. A method comprises generating observed signals in an observation path based on observing a transmit signal; down-converting the observed signals into intermediate frequencies using different LO frequencies; calculating a ratio using the intermediate frequencies; and equalizing the linear response of the observation path on the observed signals using the ratio. An apparatus comprises a directional coupler for observing a transmit signal and generating observed signals; a down-converter for converting the observed signals into intermediate frequencies using different LO frequencies; and an adaptive estimator for calculating a ratio using the intermediate frequencies and using the ratio to equalize a linear response from the observation path on the observed signals.

Method and apparatus for equalizing distortion in a digital pre-distortion observation path

A method and apparatus to digitally remove in-band non-linear signal distortion caused by a radio frequency (RF)/intermediate frequency (IF) receiver circuit that has non-linearities, which are further affected by low-IF ADC sample aliasing.

Method and apparatus for digital post-distortion compensation of signal non-linearities

Methods and systems are provided for processing electrical signals derived from coherent dual polarization optical signals. A method comprises receiving first and second input signals, filtering the input signals by first and second complex SISO FIR to generate filtered input signals, filtering the filtered input signals and the input signals by first and second two-by-two matrix filters each having four branches to respectively generate equalized filtered signals and equalized signals, and, adapting the first and second complex SISO FIR filters based on the equalized signals and the equalized filtered signals. Another method comprises filtering two random polarization input signals in a frequency-domain by overlapped FFT/IFFT blocks to generate partially equalized signals, delaying the partially equalized signals to generate delayed partially equalized signals, filtering the delayed partially equalized signals by a two-by-two matrix filter having four branches to generate equalized signals, and, adapting the FFT/IFFT blocks based on the equalized signals.

Growing community of inventors

Maple Ridge, Canada

William Dean Warner