Abstract: Downhole telemetry systems and related methods to adaptively adjust pulse waveform width through digitally controlled pulsing parameters.

Abstract: Downhole telemetry systems and related methods adaptively compensate for channel non-linearity effects. To compensate for channel non-linearity, the optimum signal generation parameters are determined that produce the desired modulated pressure variation at the surface. The signal generation parameters are optimized to minimize the discrepancy between the surface detected pressure signal and the intended signal. The mud propagation channel is first estimated in light of the known modulation scheme under an ideal linear-time-invariant channel assumption. The estimated channel is used to synthesize the modulated pressure signal undergoing the mud propagation given the initial signal generation parameters. The method then varies the synthesized signal generation parameters to search for the optimal signal generation parameters. The optimal signal generation parameters are then sent over downlink channel to the downhole pulser, which is ultimately used to generate the pulse waveform.

Abstract: This disclosure presents a process for communications in a borehole containing a fluid or drilling mud, where a conventional mud pulser can be utilized to transmit data to a transducer. The transducer, or a communicatively coupled computing system, can perform pre-processing steps to correct the received data using an average of a moving time window of the received data, and then normalize the corrected data. The corrected data can then be utilized as inputs into a machine learning mud pulse recognition network where the data can be classified and an ideal or clean pulse waveform can be overlaid the corrected data. The overlay and the corrected data can be fed into a conventional decoder or decoded by the disclosed process. The decoded data can then be communicated to another system and used as inputs, such as to a well site controller to enable adjustments to well site operation parameters.

Abstract: The disclosed embodiments include a method of downhole leak detection. The method of downhole leak detection includes obtaining physical signals detected by at least one physical sensor traveling along a wellbore. Additionally, the method includes detecting correlated sequences from the physical signals and constructing a covariance matrix based on the correlated sequences. The method also includes computing a spatial spectrum indicative of a location of a leak based on the covariance matrix.

Abstract: A downhole telemetry method and system are disclosed. In some embodiment, a method includes driving a pulser device based on an input data stream, wherein driving the pulser device includes generating modulated pressure pulses including modulated pulse shapes within a fluid telemetry medium. In some embodiments in which bi-modulation is utilized, the method further includes driving the pulser device including modulating pressure pulses including pulse position modulating pressure pulses.

Abstract: Downhole telemetry systems and related methods adaptively compensate for channel non-linearity effects. To compensate for channel non-linearity, the optimum signal generation parameters are determined that produce the desired modulated pressure variation at the surface. The signal generation parameters are optimized to minimize the discrepancy between the surface detected pressure signal and the intended signal. The mud propagation channel is first estimated in light of the known modulation scheme under an ideal linear-time-invariant channel assumption. The estimated channel is used to synthesize the modulated pressure signal undergoing the mud propagation given the initial signal generation parameters. The method then varies the synthesized signal generation parameters to search for the optimal signal generation parameters. The optimal signal generation parameters are then sent over downlink channel to the downhole pulser, which is ultimately used to generate the pulse waveform.

Abstract: Electromagnetic telemetry systems, methods to obtain downhole signals indicative of a drilling operation, and drilling data acquisition systems are presented. An electromagnetic telemetry system includes a downhole transmitter configured to transmit signals indicative of whether the downhole transmitter is in a transmission mode to transmit drilling data, a drilling data acquisition system configured to receive the signals indicative of whether the downhole transmitter is in the transmission mode, and one or more remote nodes disposed around the hydrocarbon wellsite. Each respective remote node of the one or more remote nodes configured to operate in a first mode to periodically transmit data indicative of the signal strength to the drilling data acquisition system. Each respective remote node is also configured to operate in a second mode to acquire drilling data from the downhole transmitter, and wirelessly transmit the drilling data to the drilling data acquisition system.

Abstract: A system is disclosed for optimizing mud-pulse communications in a wellbore. The system may include a mud pulser positionable in the wellbore and a surface detection system. The mud pulser can transmit a sequence of waveforms having various data rates to the surface detection system for synchronizing the mud pulser with the surface detection system. The surface detection system may receive the sequence of waveforms from the mud pulser and may determine one or more waveforms of the sequence of waveforms having amplitudes exceeding a predefined threshold. The surface detection system may then determine which of the one or more waveforms has a fastest data rate, and select the fastest data rate for use in subsequent communications with the mud pulser.

Abstract: Downhole telemetry systems and related methods to adaptively adjust pulse waveform width through digitally controlled pulsing parameters.

Abstract: This disclosure presents a process for communications in a borehole containing a fluid or drilling mud, where a conventional mud pulser can be utilized to transmit data to a transducer. The transducer, or a communicatively coupled computing system, can perform pre-processing steps to correct the received data using an average of a moving time window of the received data, and then normalize the corrected data. The corrected data can then be utilized as inputs into a machine learning mud pulse recognition network where the data can be classified and an ideal or clean pulse waveform can be overlaid the corrected data. The overlay and the corrected data can be fed into a conventional decoder or decoded by the disclosed process. The decoded data can then be communicated to another system and used as inputs, such as to a well site controller to enable adjustments to well site operation parameters.

Abstract: A system is disclosed for optimizing mud-pulse communications in a wellbore. The system may include a mud pulser positionable in the wellbore and a surface detection system. The mud pulser can transmit a sequence of waveforms having various data rates to the surface detection system for synchronizing the mud pulser with the surface detection system. The surface detection system may receive the sequence of waveforms from the mud pulser and may determine one or more waveforms of the sequence of waveforms having amplitudes exceeding a predefined threshold. The surface detection system may then determine which of the one or more waveforms has a fastest data rate, and select the fastest data rate for use in subsequent communications with the mud pulser.

Abstract: A downhole telemetry method and system are disclosed. In some embodiment, a method includes driving a pulser device based on an input data stream, wherein driving the pulser device includes generating modulated pressure pulses including modulated pulse shapes within a fluid telemetry medium. In some embodiments in which bi-modulation is utilized, the method further includes driving the pulser device including modulating pressure pulses including pulse position modulating pressure pulses.

Abstract: This disclosure presents a process for communications in a borehole containing a fluid or drilling mud, where a conventional mud pulser can be utilized to transmit data to a transducer. The transducer, or a communicatively coupled computing system, can perform pre-processing steps to correct the received data using an average of a moving time window of the received data, and then normalize the corrected data. The corrected data can then be utilized as inputs into a machine learning mud pulse recognition network where the data can be classified and an ideal or clean pulse waveform can be overlaid the corrected data. The overlay and the corrected data can be fed into a conventional decoder or decoded by the disclosed process. The decoded data can then be communicated to another system and used as inputs, such as to a well site controller to enable adjustments to well site operation parameters.

Abstract: The disclosed embodiments include a method of downhole leak detection. The method of downhole leak detection includes obtaining physical signals detected by at least one physical sensor traveling along a wellbore. Additionally, the method includes detecting correlated sequences from the physical signals and constructing a covariance matrix based on the correlated sequences. The method also includes computing a spatial spectrum indicative of a location of a leak based on the covariance matrix.

Abstract: An example method may include transmitting a first acoustic signal from a downhole tool using a transmitter gain in a transmitter circuit. A first echo signal associated with the first acoustic signal may be received at the downhole tool using a receiver gain in a receiver circuit. At least one of the transmitter gain and the receiver gain may be adjusted based, at least in part, on the received first echo signal and at least one previously received echo signal.

Abstract: A digital telemetry system can be calibrated to improve data communication. A receiver can receive a modulated signal with a predetermined sequence of transmitted symbols. A processing device can be communicatively coupled to the receiver for jointly performing carrier phase synchronization and symbol-timing recovery on the modulated signal to determine a corrective phase offset and a corrective timing offset. The receiver can be calibrated to use the corrective phase offset and the corrective timing offset for demodulating a subsequently modulated signal. In additional or alternative aspects, a demodulator can demodulate the modulated signal and determine an amount of interference introduced to the modulated signal. A transmitter can transmit data based on the amount of interference to a modem that transmitted the modulated signal for use by the modem to dynamically adjust hit allocation of the subsequently modulated signal.

Abstract: A resistivity logging tool includes a plurality of excitation electrodes, at least one return electrode, and a plurality of monitor electrodes. The resistivity logging tool also includes a controller that determines a set of independent currents to be emitted by at least some of the plurality of excitation electrodes during an excitation cycle based on at least one measured downhole parameter and at least one predetermined constraint.

Abstract: A resistivity logging system includes a plurality of excitation electrodes, at least one return electrode, and a plurality of monitor electrodes. The resistivity logging system also includes a controller that determines a level of excitation current to be emitted by at least one of the plurality of excitation electrodes during a subsequent excitation cycle based on a comparison of measured downhole parameter values corresponding to excitation current emitted in two previous excitation cycles.

Abstract: An example method may include transmitting a first acoustic signal from a downhole tool using a transmitter gain in a transmitter circuit. A first echo signal associated with the first acoustic signal may be received at the downhole tool using a receiver gain in a receiver circuit. At least one of the transmitter gain and the receiver gain may be adjusted based, at least in part, on the received first echo signal and at least one previously received echo signal.

Abstract: A resistivity logging tool includes a plurality of excitation electrodes, at least one return electrode, and a plurality of monitor electrodes. The resistivity logging tool also includes a controller that determines a set of independent currents to be emitted by at least some of the plurality of excitation electrodes during an excitation cycle based on at least one measured downhole parameter and at least one predetermined constraint.