Multiplexed Signals Patents (Class 340/855.3)
  • Patent number: 10222507
    Abstract: Disclosed herein are various telemetry systems and methods suitable for communicating a cylindrical volume of formation property measurements to the surface. Some system embodiments include a downhole processor coupled to a telemetry transmitter. The downhole processor determines a compressed representation of the formation property measurements and/or selects a subset of the measurements for transmission uphole. The subset selection can be based on selected radial distances having characteristics that potentially indicate features of interest to a user. Such features include bed boundaries, and the characteristics include sinusoidal variation as a function of azimuth, large changes in this sinusoidal variation versus radial distance, or inversion suggesting the presence of a bed boundary.
    Type: Grant
    Filed: November 19, 2008
    Date of Patent: March 5, 2019
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Michael S. Bittar, Clive D. Menezes
  • Patent number: 10145211
    Abstract: Aspects of the disclosure can relate to an adapter for power and communication connections between electronic devices in a drill string. In embodiments, the adapter can include a first terminal configured to couple with an output terminal of a first tool and a second terminal configured to couple with an input terminal of a second tool. The adapter can further include a power converter that adjusts a voltage received at the first terminal and supplies the adjusted voltage to the second terminal and a communications adapter that converts a signal format of a communications signal received at the first terminal to a second signal format for the second terminal.
    Type: Grant
    Filed: September 10, 2015
    Date of Patent: December 4, 2018
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: David Santoso, Randall LeBlanc
  • Patent number: 10121365
    Abstract: A sensor system includes a controller and sensors. The controller is to transmit a signal. The sensors are connected to the controller in series via at least one cable to sequentially transfer the signal transmitted from the controller via the at least one cable.
    Type: Grant
    Filed: March 17, 2017
    Date of Patent: November 6, 2018
    Assignee: KABUSHIKI KAISHA YASKAWA DENKI
    Inventor: Kunihiko Ogawa
  • Patent number: 10072494
    Abstract: A system for determining a characteristic of an oil well includes a signal source to generate an excitation signal during a first time duration and to generate a local oscillator signal during a second time duration. The system further includes a directional coupler, and a resonator disposed in an annulus of an oil well to receive the excitation signal through the directional coupler. The system also includes a mixer to receive a resonator signal from the resonator through the directional coupler, to receive the local oscillator signal, and to generate a mixer output signal based on the resonator signal and the local oscillator signal. The system further includes a filter to filter the mixer output signal to produce an intermediate frequency signal having an intermediate frequency, and a processor to determine a pressure or a temperature experienced by the resonator based on the intermediate frequency signal and the excitation signal.
    Type: Grant
    Filed: November 24, 2015
    Date of Patent: September 11, 2018
    Assignee: CHEVRON U.S.A. INC.
    Inventors: Melvin Clark Thompson, David William Beck
  • Patent number: 9976412
    Abstract: A system and method for transmitting data over a three phase power system between a surface and a sub-surface location. A first power supply providing a first AC power signal and a second power supply providing a second AC power signal are at the surface. A first powered module and a second powered module which provides a data communications signal are at the sub-surface. A cable connection is provided between the surface and the sub-surface to transmit the power and data communication signals. The data communications signal provides an indication of power applied to the second powered module and a power signal is varied in response to the applied power. The invention finds specific application monitoring down hole equipment such as an electrical submersible pump in a wellbore.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: May 22, 2018
    Assignee: Zenith Oilfield Technology Limited
    Inventor: David Sirda Shanks
  • Patent number: 9939315
    Abstract: A sensor with integrated mechanical transducing and temperature monitoring capability is provided. The sensor includes housing containing a transducer, a temperature sensor with associated bias, a summing circuit, and a two-wire cable connector. The transducer is operable to output a dynamic transducer waveform that corresponds to dynamic mechanical perturbations sensed by the transducer. The temperature sensor is operable to output a quasi-static temperature waveform that corresponds to temperatures sensed by the temperature sensor. The summing circuit is operable to combine the transducer waveform and the temperature waveform into a composite modulated voltage bias output signal or a modulated current bias output signal. The two-wire cable connector is accessible on an outside of the housing and is connectable to a two wire cable that delivers power to the sensor from a power source and delivers the composite output signal from the sensor to a remote data acquisition circuit.
    Type: Grant
    Filed: August 8, 2015
    Date of Patent: April 10, 2018
    Assignee: Vibration Measurement Solutions, Inc.
    Inventor: George V. Zusman
  • Patent number: 9787482
    Abstract: According to one aspect, embodiments of the invention provide a method for providing power to a distributed sensor system, the method comprising providing power from at least one port of an interface unit to a first port of a first sensor unit of at least one of a plurality of sensor strings, powering up the first sensor unit, forwarding power from a second port of the first sensor unit to a first port of a second sensor unit of the at least one of the plurality of sensor strings, powering up the second sensor unit, monitoring the plurality of sensor strings for a fault condition, and in response to detecting a fault condition in a first sensor string of the plurality of sensor strings, providing power from a second one of the plurality of sensor strings to the first sensor string.
    Type: Grant
    Filed: October 15, 2015
    Date of Patent: October 10, 2017
    Assignee: Raytheon BBN Technologies Corp.
    Inventors: Stephen D. Milligan, Dale Gordon Robertson
  • Patent number: 9588249
    Abstract: The present invention relates to a downhole well-operation system for operating a driving unit and a logging tool downhole and transmitting well-logging data from at least one logging tool to a surface data acquisition system by means of a wireline. The system comprises a surface transceiver, a wireline, a downhole transceiver, a logging tool, and a driving unit, wherein the downhole transceiver is coupled to the surface transceiver via the wireline and communicates to the surface transceiver using orthogonal frequency division multiplexing to transmit data via the wireline by modulating a Pulse Width Modulated (PWM) signal to the wireline by means of a transistor bridge, while the driving unit and at least one logging tool is powered by the wireline. Furthermore, the invention relates to a downhole tool.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: March 7, 2017
    Assignee: WELLTEC A/S
    Inventor: Jørgen Hallundbæk
  • Patent number: 9395434
    Abstract: A multitone nonlinear radar system (and a method of operating such a system) comprising a transmitter that transmits a signal comprising at least two predetermined frequency components; a receiver operating to receive return signals comprising harmonics of at least two predetermined frequencies, combinations of the at least two predetermined frequency components, and combinations of the harmonics of the at least two predetermined frequency components that are within a predetermined selected frequency range that has been predetermined to enable detection and/or classification of an electronic device; at least one antenna operating to transmit and receive electromagnetic radiation operatively connected to the transmitter and receiver; the receiver comprising at least one high pass filter for attenuating linear reflections at the two predetermined frequencies, and an analyzer; whereby electronic devices may be detected and identified by analyzing return signals within a predetermined frequency range.
    Type: Grant
    Filed: April 25, 2013
    Date of Patent: July 19, 2016
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Gregory James Mazzaro, Anthony F Martone
  • Patent number: 9175523
    Abstract: An apparatus that is usable with a well includes a first equipment section that includes a first inductive coupler and a second equipment section that includes a second inductive coupler. The second equipment section is adapted to be run downhole into the well after the first equipment section is run downhole into the well to engage the first equipment section. A mechanism of the apparatus indicates when the first inductive coupler is substantially aligned with the second inductive coupler.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: November 3, 2015
    Assignee: Schlumberger Technology Corporation
    Inventors: Dinesh Patel, Donald W. Ross, Anthony Frank Veneruso, Fabien Cens, John R. Lovell, Ian Stuart Mackay
  • Patent number: 9046623
    Abstract: Gamma pulse telemetry. At least some of the illustrative embodiments are methods including: reading data associated with a borehole penetrating an earth formation; encoding the data in a first plurality of gamma bursts, the encoding by an encoding system coupled within the drill string, and where the each gamma burst travels a first distance along the borehole; receiving the first plurality of gamma bursts by a receiver system coupled within the drill string; and decoding the first plurality of gamma bursts and thereby recovering the data.
    Type: Grant
    Filed: May 8, 2012
    Date of Patent: June 2, 2015
    Assignee: HALLIBURTON ENERGY SERVICES, INC.
    Inventors: Paul A. Cooper, Kevin R. Kapka
  • Publication number: 20150029036
    Abstract: Provided are systems and methods for ground fault immune data measurement system for electric submersible pumps. A data measurement system coupled to the ESP includes a surface unit coupled to a 3-phase power cable for providing power to a 3-phase motor of the ESP and a downhole unit coupled to the motor of the ESP and located downhole in a well. The downhole unit includes sensor and is configured to generate frequency modulated carrier signals for carrying the sensor data to the surface unit. Each of the frequency modulated carrier signals carries identical sensor data and is modulated to a different frequency. The carrier signals are shunted across the motor windings of the ESP motor and onto the 3-phase power cable via a capacitive coupling. Additionally, another carrier signal carrying control data may be transmitted from the surface unit to the downhole unit.
    Type: Application
    Filed: July 28, 2013
    Publication date: January 29, 2015
    Applicant: Saudi Arabian Oil Company
    Inventors: Jinjiang Xiao, Michael Manning
  • Publication number: 20140340235
    Abstract: Methods and apparatus for fast sweeping a spectral bandwidth in order to distinguish among signals received from effectively wavelength division multiplexed (WDMed) and time division multiplexed (TDMed) optical components on a single fiber. For some embodiments, a method for interrogating optical elements having characteristic wavelengths spanning a sweep range is provided. The method generally includes introducing a pulse of light, by an optical source, into an optical waveguide to interrogate at least a first set of optical elements having different characteristic wavelengths by performing a sweep of wavelengths over a period of the pulse, wherein the period is less than a round-trip time for light reflected from an optical element closest to the optical source to reach a receiver and processing the reflected light to determine a parameter based on the times at which signals are received.
    Type: Application
    Filed: May 13, 2014
    Publication date: November 20, 2014
    Applicant: WEATHERFORD/LAMB, INC.
    Inventor: Domino TAVERNER
  • Patent number: 8811118
    Abstract: Pressure measurements are made using a pressure sensor in the proximity of the drillbit during drilling operations. A filtered version of the pressure measurements is provided to a pulser for a mud-pulse telemetry system so as to cancel pressure variations due to drilling noise while a telemetry signal is being sent. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: August 19, 2014
    Assignee: Baker Hughes Incorporated
    Inventor: Hanno Reckmann
  • Patent number: 8788210
    Abstract: Job monitoring methods and apparatus for logging-while-drilling equipment are disclosed. A disclosed example method includes identifying a downhole scenario based on a property of an underground geological formation, selecting a first telemetry frame type based on the identified downhole scenario, conveying an identifier representative of the selected first telemetry frame type to a downhole fluid sampling tool, and receiving a first telemetry data frame from the downhole fluid sampling tool, the telemetry data frame containing fluid analysis parameters for a fluid, and being constructed in accordance with the selected first telemetry frame type.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: July 22, 2014
    Assignee: Schlumberger Technology Corporation
    Inventors: Sylvain Ramshaw, Julian J. Pop, Peter Swinburne, Kai Hsu, Steven Villareal
  • Publication number: 20140077965
    Abstract: Systems and methods of signal transmission and measuring for sensors employing a transmission medium are provided. In one embodiment, a method may comprise measuring a first monitored condition to generate a first monitored condition signal; converting the first monitored condition signal to a first frequency modulated signal having a first frequency; generating a second frequency modulated signal having a reference frequency; transmitting the first frequency modulated signal and the second frequency modulated signal using time division multiplexing; and wherein a first ratio of the first frequency and the reference frequency is associated with the first pressure.
    Type: Application
    Filed: November 18, 2013
    Publication date: March 20, 2014
    Applicant: Kulite Semiconductor Products, Inc.
    Inventor: Wolf S. Landmann
  • Patent number: 8602108
    Abstract: An embodiment of a method for limiting the probability of failure on demand of a subsea test tree (“SSTT”) includes the steps of providing a safety shut-in system for actuating a safety valve of the SSTT, the safety shut-in system including a surface control station positioned above a water surface connected via an umbilical to a subsea control system positioned below the water surface to actuate the safety valve; and diagnostically testing the safety shut-in system without actuating the safety valve.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: December 10, 2013
    Assignee: Schlumberger Technology Corporation
    Inventor: David James Mathis
  • Patent number: 8576090
    Abstract: Apparatus and methods for controlling and communicating with one or more tools in a downhole tool string including a tractor, an auxiliary tractor tool, a logging tool, a safety sub, a release mechanism, a unit containing sensors for monitoring downhole conditions, a setting tool, and a perforating gun. Also provided are apparatus and methods for controlling and communicating with one or more perforating guns, release devices, and explosive devices in a string to be lowered into a wellbore. Control and communication are accomplished by sending signals from the surface to control switches in the control units on the tool, with redundant switches for safety, to state machines in the respective control units, each state machine returning a signal verifying switch status to the surface. Control and power functions are accomplished with voltage of different polarities for safety.
    Type: Grant
    Filed: August 5, 2008
    Date of Patent: November 5, 2013
    Assignee: Hunting Titan, Ltd.
    Inventors: Nolan C. Lerche, James E. Brooks
  • Patent number: 8514098
    Abstract: The present disclosure relates to a method to determine a clock signal when separate clocks are used. In one embodiment, a disciplined clock system comprising an update subsystem and a synthesis subsystem is provided. A first clock phase estimate is provided to the update subsystem and used, along with the update subsystem, to determine a frequency offset estimate and a phase offset estimate. The clock signal is determining using the frequency offset estimate, the phase offset estimate, and the synthesis subsystem. Alternatively, two clocks can be synchronized by generating a signal associated with a first clock; modulating the signal; transmitting the modulated signal; receiving the modulated signal by a receiver associated with a second clock; correlating the received signal; determining the time of arrival of the received signal; determining the time difference between the two clocks; and synchronizing the two clocks.
    Type: Grant
    Filed: June 17, 2010
    Date of Patent: August 20, 2013
    Assignee: Schlumberger Technology Corporation
    Inventors: Michael Montgomery, Julius Kusuma, Jean Seydoux, Desheng Zhang
  • Patent number: 8487779
    Abstract: An electronic module for use as a subsea electronic module for an underwater fluid extraction well, wherein a local area network enables communication within the module, the local area network including a plurality of interfaces with components of the network, and wherein the interfaces comprise capacitive coupling interfaces.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: July 16, 2013
    Assignee: Vetco Gray Controls Limited
    Inventor: Julian R. Davis
  • Patent number: 8446292
    Abstract: Systems and methods for reliably communicating data between surface and downhole equipment over a power cable, regardless of the length of the power cable, wherein a transmitter modulates a common data stream onto multiple high frequency carrier signals, each of which has a different frequency. Each of the different frequencies is best suited to communication over a different length of cable. The resulting modulated high frequency data signals are impressed on the power cable and are recovered from the cable by a receiver. The receiver is configured to recover signals at each of the different carrier frequencies, at least one of which should be transmitted with little enough attenuation and interference that the data stream can be accurately recovered from the corresponding modulated high frequency data signal.
    Type: Grant
    Filed: July 29, 2010
    Date of Patent: May 21, 2013
    Assignee: Baker Hughes Incorporated
    Inventor: James E. Layton
  • Patent number: 8433520
    Abstract: Job monitoring methods and apparatus for logging-while-drilling equipment are disclosed. A disclosed example method includes obtaining a fluid associated with an underground geological formation, analyzing the fluid with one or more sensors to form respective ones of sensor outputs, identifying a downhole scenario associated with the fluid based on the sensor outputs, the identifying being performed while the sensors are within the underground geological formation, and selecting a telemetry frame type based on the identified downhole scenario.
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: April 30, 2013
    Assignee: Schlumberger Technology Corporation
    Inventors: Sylvain Ramshaw, Julian J. Pop, Peter Swinburne, Kai Hsu, Steven G. Villareal
  • Patent number: 8432294
    Abstract: An electronic module for use as a subsea electronic module (SEM) for an underwater fluid extraction well, as provided. An example of such an SEM includes a plurality of substantially planar electronics cards to operate devices in the SEM. The cards are arranged in a stack such that major faces of each card are oriented substantially parallel to, and coaxial with, major faces of the other cards in the stack. The SEM also includes a substantially planar switch card orientated relative to the stack such that its major faces are oriented substantially parallel to a main axis of the stack and orthogonal to the orientation of the major faces of the electronics cards within the stack. The switch card includes a first Ethernet switch blade configured to control traffic on a LAN area network and a second Ethernet switch blade configured to control traffic on a second LAN.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: April 30, 2013
    Assignee: Vetco Gray Controls Limited
    Inventor: Julian R. Davis
  • Patent number: 8237584
    Abstract: In one aspect of the present invention, a method for tool string communication comprises the steps of providing a downhole tool string with at least two downhole LWD/MWD instruments in electrical communication with a downhole telemetry system. The instruments are capable of generating at least one data packet assigned a priority. The tool string is deployed in a wellbore and then the priority of the data packet is changed.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: August 7, 2012
    Assignee: Schlumberger Technology Corporation
    Inventors: David R. Hall, Christopher Durrand, Brad Barger
  • Patent number: 8184014
    Abstract: An apparatus includes a transmission line for deployment in a well, and a driver to transmit signals over the transmission line. The driver includes a field-effect transistor, and an operational amplifier to control the field-effect transistor, where the operational amplifier and field-effect transistor cooperate to form a voltage-to-current converter.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: May 22, 2012
    Assignee: Schlumberger Technology Corporation
    Inventor: Ramon Hernandez-Marti
  • Publication number: 20120037354
    Abstract: Systems and methods for reliably communicating data at high data rates between surface and downhole equipment over a power cable by multiplexing data, modulating the data onto orthogonal carrier frequencies, communicating the modulated carrier signals over the power cable, recovering of the modulated signals, and demodulating the data stream from the recovered signal. One embodiment comprises a system that includes surface equipment connected by a power cable to an ESP system that has a gauge package connected to it. The gauge package uses a high-temperature DSP to perform the data processing associated with OFDM communications.
    Type: Application
    Filed: August 12, 2010
    Publication date: February 16, 2012
    Inventors: Robert H. McCoy, Gordon L. Besser, Stewart D. Reed, Dustin B. Campbell, Dick L. Knox
  • Patent number: 8094516
    Abstract: A method for the time-serial transmission of received signals of electroacoustic transducers (11), which are placed at different transducer locations (13) of a spatially spread receive arrangement (10), to a signal processing unit (12), in which at each transducer location (13) the received signals are digitized by an electronic module (20), and the digitized received signals are switched onto a data line (14, 15, 16) leading to the signal processing unit (12) in the timing pattern of a synchronization clock. To obtain a high data rate with undisturbed data transmission, the intrinsic switching-time errors of the electronic modules (20) are measured with respect to the switching times defined by the timing pattern, and compensated for at the transducer locations (13) by individual time delay of the signals to be switched.
    Type: Grant
    Filed: October 10, 2007
    Date of Patent: January 10, 2012
    Assignee: Atlas Elektronik GmbH
    Inventors: Peter Hoffman, Kersten Mölck, Eberhard Schmidt
  • Patent number: 8014483
    Abstract: A receiver in an impulse wireless communication. The receiver (300) includes a pulse-pair correlator (304) that receives a signal (316) and divides it into two signals for paths. One of the signals is input to signal multiplier (312) while another signal is delayed by a delay unit (310). The signal multiplier (312) multiplies the received signal (316) by a delayed signal (318). An integrator (314) integrates an output signal (322) over a designated period of time. An adding module (306) sums an output signal (324) from the integrator (314). An acquiring module (308) compares an summing-up output (326) from the adding module (306) with a predetermined threshold value to detect the existence of a transmitting-standard preamble.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: September 6, 2011
    Assignee: Panasonic Corporation
    Inventors: Yew Soo Eng, Zhan Yu
  • Patent number: 7894302
    Abstract: A drilling system utilizing a plurality of independent telemetry systems. The drilling system uses a drill collar as a pressure housing for downhole components of the system. One or more sensors are disposed within the pressure housing. These sensors can be MWD sensors, LWD sensors, or both MWD and LWD sensors. A plurality of independent borehole telemetry systems is used to telemeter sensor response data to the surface of the earth. Each sensor cooperates with a downhole component of at least one of the independent telemetry systems. The plurality of telemetry systems can be of the same type, such as a mud pulse systems. Alternately, the telemetry systems can be of different types including a mud pulse system and an electromagnetic system.
    Type: Grant
    Filed: December 7, 2006
    Date of Patent: February 22, 2011
    Assignee: Precision Energy Services, Inc.
    Inventors: Robert Anthony Aiello, Michael Louis Larronde, John Martin, Steven R. Farley, Kirk Towns
  • Patent number: 7868574
    Abstract: A motor absolute position signal processing apparatus connected to a signal processor and an optical encoder of a motor control system includes first and second switches, a signal integration amplifier, first and second separators and an inverter. The first switch is connected with the optical encoder, the second switch with the optical encoder and the first switch, the signal integration amplifier with the first and second switches, the first separator with the signal integration amplifier and the signal processor, and the second separator with the signal processor. An input end of the inverter is connected with the second separator and an output end with the second switch. The signal processor outputs an enable signal to be processed by the inverter for switching the first or second switch. The signal integration amplifier processes and transmits two sets of differential signals SIN;/SIN and COS;/COS of the optical encoder to the signal processor.
    Type: Grant
    Filed: January 15, 2008
    Date of Patent: January 11, 2011
    Assignee: Delta Electronics, Inc.
    Inventor: Wen-Cheng Hsieh
  • Patent number: 7772795
    Abstract: A motor position signal processing apparatus electrically connected to a signal processor and an optical encoder of a motor control system includes a first switch, a second switch, a first signal integration amplifier, a first separator, a second signal integration amplifier, a second separator, a third signal integration amplifier, a third separator, a fourth separator and an inverter. An enable signal outputted by the signal processor is processed by the inverter to switch the operation to the first switch or the second switch. An incremental signal outputted by the optical encoder, a motor mechanical position and a reset correction signal are processed by the first, second and third signal integration amplifiers and transmitted to the signal processor for controlling the operation of a motor.
    Type: Grant
    Filed: January 21, 2008
    Date of Patent: August 10, 2010
    Assignee: Delta Electronics, Inc.
    Inventor: Wen-Cheng Hsieh
  • Publication number: 20100156662
    Abstract: An electronic module for use as a subsea electronic module for an underwater fluid extraction well, wherein a local area network enables communication within the module, the local area network including a plurality of interfaces with components of the network, and wherein the interfaces comprise capacitive coupling interfaces.
    Type: Application
    Filed: December 17, 2009
    Publication date: June 24, 2010
    Applicant: Vetco Gray Controls Limited
    Inventor: Julian R. Davis
  • Patent number: 7696901
    Abstract: Subterranean oilfield sensor systems and methods are provided. The subterranean oilfield sensor systems and methods facilitate downhole monitoring and high data transmission rates with power provided to at least one downhole device by a light source at the surface. In one embodiment, a system includes uphole light source, a downhole sensor, a photonic power converter at the downhole sensor, an optical fiber extending between the uphole light source and the photonic power converter, and downhole sensor electronics powered by the photonic power converter. The photonic power converter is contained in a high temperature resistant package. For example, the high temperature resistant package and photonic power converter may operate at temperatures of greater than approximately 100° C.
    Type: Grant
    Filed: September 19, 2006
    Date of Patent: April 13, 2010
    Assignee: Schlumberger Technology Corporation
    Inventors: Colin Wilson, Soon Seong Chee, Les Nutt, Tsutomu Yamate, Masahiro Kamata
  • Publication number: 20100039286
    Abstract: Enhanced symbol synchronization methods suitable for use in narrowband orthogonal frequency division multiplexed (OFDM) telemetry systems. In at least some embodiments, a logging while drilling (LWD) tool assembly communicates with the surface using low frequency electromagnetic (EM) signals. The telemetry transmitter employs OFDM modulation to fully exploit the narrow range of available bandwidth, resulting in signals that have relatively long frames. At the surface a receiver digitizes the receive signal and applies an enhanced symbol synchronization technique to identify frame boundaries before demodulation is attempted. The enhanced symbol synchronization technique employs a pulse train filter to clean up a cyclic prefix correlation signal that otherwise behaves badly in the narrowband regime. The improved timing information from the enhanced symbol synchronization significantly reduces the error rate in the demodulated signal.
    Type: Application
    Filed: August 18, 2008
    Publication date: February 18, 2010
    Applicant: Halliburton Energy Services, Inc.
    Inventor: Carl A. ROBBINS
  • Patent number: 7620394
    Abstract: A communications system includes a first wireless communications system configured to provide wireless communications over a first frequency band, and a second wireless communications system configured to provide wireless communications using at least a portion of the first frequency band. The system includes an inter-system communications link between the first wireless communications system and the second wireless communications system. The inters-system communications link is used to coordinate the use of the first frequency band. The system further includes an interference reducer configured to reduce interference between the first wireless communications system and the second wireless communications system. Related methods are also disclosed.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: November 17, 2009
    Assignee: ATC Technologies, LLC
    Inventors: Alexander H. Good, Charlene J. King, Eric A. Swank, Monish Kundra, Peter D. Karabinis
  • Publication number: 20090267790
    Abstract: In one aspect of the present invention, a method for tool string communication comprising the steps of: providing a downhole tool string with at least two downhole LWD/MWD instruments in electrical communication with a downhole telemetry system, the instruments being capable of generating at least one data packet assigned a priority; then deploying the tool string in a well bore; and then changing the priority of the data packet.
    Type: Application
    Filed: January 30, 2009
    Publication date: October 29, 2009
    Inventors: David R. Hall, Christopher Durrand, Brad Barger
  • Publication number: 20090207041
    Abstract: A method of measuring while drilling includes positioning at least one sensor downhole; and transmitting sensed data while drilling from the at least one sensor to surface without storing the sensed data downhole and system.
    Type: Application
    Filed: February 19, 2009
    Publication date: August 20, 2009
    Applicant: Baker Hughes Incorporated
    Inventors: Ralf Zaeper, Michael W. King
  • Patent number: 7570175
    Abstract: Token authorized node discovery between a plurality of store-and-forward nodes in a downhole networking environment and respective applications for data processing and communication are described herein.
    Type: Grant
    Filed: February 14, 2007
    Date of Patent: August 4, 2009
    Assignee: IntelliServ International Holding, Ltd.
    Inventors: Monte Johnson, Mark Stillings, David Bartholomew
  • Publication number: 20090146837
    Abstract: A system for communicating information in a borehole between tool assemblies in a tool string includes receiving an information signal and separating a first signal that may be a power and low speed signal. A second signal is separated and demodulated from the information signal. The first signal and second signal are transmit to electronic devices that process data from an earth formation. After the first and second signals are transmit to one or more electronic devices, the signals are modulated and/or filtered and then combined into the information signal. The first signal is at one frequency and the second signal is at a different frequency. The apparatus includes a main signal line that couples to a second signal line and third signal line in the tool assembly.
    Type: Application
    Filed: January 12, 2009
    Publication date: June 11, 2009
    Applicant: Halliburton Energy Services, Inc.
    Inventor: Marian Morys
  • Patent number: 7468678
    Abstract: A communications system employing discrete multi-tone (“DMT”) modulated signals on a communications channel formed by inductively-coupled pipe. In one embodiment, the communications system includes a string of wired pipe joints that couple a transmitter to a receiver. Each pipe joint in the string possesses threaded ends configured for mechanically connecting with other pipe joints, a electrical or inductive coupler at each threaded end, and an insulated conductor that electrically connects the couplers. The transmitter and receiver communicate via DMT modulated signals transported by the wired pipe string. The system may further include multiple repeaters in the string. Each repeater may be configured to receive a DMT-modulated signal, to recover information from the DMT-modulated signal, and to retransmit the information in the form of a DMT-modulated signal.
    Type: Grant
    Filed: November 15, 2006
    Date of Patent: December 23, 2008
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Vimal V. Shah, Wallace R Gardner
  • Patent number: 7443312
    Abstract: Improved communication systems and methods are disclosed. In one embodiment, a downhole communications system comprises a downhole transceiver and a surface transceiver. The surface transceiver receives a discrete multi-tone (DMT) modulated uplink signal from the downhole transceiver, and transmits a downlink signal to the downhole transceiver using a modulation method determined by the transceivers as communications are initiated. The downlink modulation methods supported by the surface transceiver may include DMT modulation and quadrature amplitude modulation (QAM). The modulation mode selection may be based on measured channel characteristics, on proposed data rates, or on other predetermined parameters. The uplink and downlink signals may be communicated over a shared transmission mode on multiconductor cable or wired pipe, and alternatively the uplink and downlink signals may be communicated over separate transmission modes.
    Type: Grant
    Filed: June 8, 2004
    Date of Patent: October 28, 2008
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Alberto Quintero, Carl Dodge, Homi P. Cooper, Wallace R. Gardner
  • Publication number: 20080180273
    Abstract: Self-detection of a modulating carrier and an optimum carrier in a downhole telemetry system. A method of detecting a carrier frequency in a downhole wireless telemetry system includes the steps of: transmitting from a first telemetry device a message modulated on a predetermined carrier frequency; receiving at a second telemetry device signals including multiple frequencies; and selecting from among the multiple received frequencies the predetermined carrier frequency on which the message is modulated. A method of detecting a usable downhole wireless telemetry system carrier frequency includes the steps of: transmitting from a first telemetry device a message modulated on a carrier frequency; then checking whether a response to the message is received at the first telemetry device from a second telemetry device; and each time the response is not received, repeating the transmitting and checking steps with an incremented carrier frequency.
    Type: Application
    Filed: January 29, 2007
    Publication date: July 31, 2008
    Inventors: Donald G. Kyle, Kevin D. Fink
  • Patent number: 7250857
    Abstract: A multiplexing system is provided for a plurality of sensors disposed in a tank containing a potentially explosive environment and excited from a common excitation circuit outside of the tank through a corresponding plurality of signal lines that penetrate the tank. The multiplexing system comprises: a multiplexer switch for each sensor, each multiplexer switch disposed outside of the tank in series with the corresponding signal line between the common excitation circuit and the corresponding sensor in the tank.
    Type: Grant
    Filed: December 22, 2003
    Date of Patent: July 31, 2007
    Assignee: Simmonds Precision Products, Inc.
    Inventor: Lawrence Carl Maier
  • Patent number: 7187298
    Abstract: Methods and systems for transmitting and receiving a discrete multi-tone (DMT) modulated signal in a fluid. Some illustrative embodiments may be a method comprising transforming an input data series into an information-carrying signal (the information-carrying signal carrying input data from the input data series as modulations of at least one of a plurality of evenly spaced frequency bins), and applying the information-carrying signal to a transducer that converts the information-carrying signal into pressure variations within a fluid.
    Type: Grant
    Filed: January 13, 2005
    Date of Patent: March 6, 2007
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Wallace R. Gardner, Vimal V. Shah
  • Patent number: 7180825
    Abstract: A communications system employing discrete multi-tone (“DMT”) modulated signals on a communications channel formed by inductively-coupled pipe. In one embodiment, the communications system includes a string of wired pipe joints that couple a transmitter to a receiver. Each pipe joint in the string possesses threaded ends configured for mechanically connecting with other pipe joints, a electrical or inductive coupler at each threaded end, and an insulated conductor that electrically connects the couplers. The transmitter and receiver communicate via DMT modulated signals transported by the wired pipe string. The system may further include multiple repeaters in the string. Each repeater may be configured to receive a DMT-modulated signal, to recover information from the DMT-modulated signal, and to re-transmit the information in the form of a DMT-modulated signal.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: February 20, 2007
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Vimal V. Shah, Wallace R. Gardner
  • Patent number: 7158048
    Abstract: Apparatus for conducting geophysical surveys comprising a multiplicity of intelligent electrodes provided on a multi-conductor cable, for receiving a command signal in response to which predetermined electrodes are connected to selected conductors in the cable. Each intelligent electrode is identical in all respects, including its programming, resulting in simplified construction of the cable and easy replacement of the intelligent electrodes. Instead of assigning a unique address code to each switch in a series of take-outs on a multi-conductor cable, each electronic switch is programmed with the same address code. That is, each switch is programmed to be activated when it receives a code command that, for example, is prefaced with a particular address, e.g. the number 1. The second part of the code (y) instructs the switch as to which conductor in the multi-conductor cable is to be connected to the local electrode at the location of the switch.
    Type: Grant
    Filed: October 9, 2003
    Date of Patent: January 2, 2007
    Assignee: Scintrex Limited
    Inventor: Abderrahim Abdelhadi
  • Patent number: 7106210
    Abstract: A method and related apparatus for telemetry between downhole devices and surface devices. In particular, the methods and related apparatus may send a first datum of a first parameter in an uncompressed form, and send a second datum of the first parameter in compressed form.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: September 12, 2006
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Christopher A. Golla, Laban M. Marsh, Paul F. Rodney, Cili Sun, Bipin K. Pillai, Paul D. Beene
  • Patent number: 7026952
    Abstract: A downhole telemetry system and method using discrete multi-tone modulation having repeated symbols. The system includes a surface receiver, a cable, and a downhole transmitter coupled to the surface receiver via the cable. The transmitter communicates a time-domain signal to the receiver. The time-domain signal has a cyclic prefix for a symbol at least as long as the length of the symbol. The system may alternatively include the time-domain signal having a symbol followed immediately by a copy of the symbol. The method includes receiving a time-domain signal carrying desired information at specific frequencies. The signal has at least one symbol. The method includes prepending a cyclic prefix having first length to the beginning of the symbol. The cyclic prefix has a second length no longer than the first length. The method may alternatively include appending a copy of the at least one symbol to the end of the at least one symbol.
    Type: Grant
    Filed: February 21, 2003
    Date of Patent: April 11, 2006
    Assignee: Halliburton Energy Services, Inc.
    Inventor: Daniel J. Krueger
  • Patent number: 7000693
    Abstract: An apparatus controls the operation of a hydrocarbon production well. The apparatus includes a supply means for providing an electric power supply. The apparatus also includes a plurality of electrically operated actuating devices. The actuating devices can be a plurality of electric motors. The apparatus includes drivers responsive to the power supply for providing a drive signal for the actuating devices. The apparatus also includes a control assembly for applying the drive signal to the actuating devices in a multiplexed manner. The power from each driver creates a power input signal. When there are more than one input signals, they are multiplexed so that a single signal is received by the actuating devices.
    Type: Grant
    Filed: April 7, 2003
    Date of Patent: February 21, 2006
    Assignee: Vetco Gray Controls Limited
    Inventor: Steven Robert Powell
  • Patent number: 6937159
    Abstract: A power transmission and data communications system for use in a gas or oil well borehole is disclosed. The borehole includes a casing and a piping structure therein and at least one downhole equipment module located therein. The system provides for a power signal to provide power transfer to downhole systems that require power and for data and control signals to be transmitted using orthogonal frequency division multiplexing (OFDM) to the downhole equipment located in the downhole equipment modules. In particular, the system provides for the data signal to be electrically coupled to the case and piping structure for transmission downhole to the downhole systems that are similarly coupled to the casing and piping structure. The downhole equipment includes a power supply that is operative to recover electrical power from the power signal and to provide output power to the other downhole equipment.
    Type: Grant
    Filed: February 1, 2002
    Date of Patent: August 30, 2005
    Assignee: DBI Corporation
    Inventors: Lawrence W. Hill, F. Williams Sarles