By Fourier Analysis Patents (Class 324/76.21)
  • Patent number: 11942987
    Abstract: The present disclosure provides a method. The method comprises: Step S1: configuring a periodic excitation source to transmit a periodic excitation signal A; Step S2: sampling an output signal A+NA at an output point of the periodic excitation signal A with a sampling device AA, and averaging the output signal A+NA over one or more periods to filter noise; Step S3: inputting the sampled output signal A+NA as in input to a device or a channel H to be measured; Step S4: sampling an output signal B+NB at an output point of the device or the channel H to be measured with a sampling device BB, and averaging the output signal B+NB over one or more periods to filter noise; and Step S5: transmitting sampling results from the sampling device AA and the sampling device BB to an analysis software C to calculate a transfer function of the device or the channel H to be measured.
    Type: Grant
    Filed: March 29, 2022
    Date of Patent: March 26, 2024
    Assignee: SHAN DONG SITRUS TECHNOLOGY CO., LTD.
    Inventors: Hui Wang, Jiongming Wang
  • Patent number: 11172091
    Abstract: A photoelectric conversion device includes a plurality of pixels configured to output analog voltage signals in response to incident light; an analog memory configured to store the analog voltage signals output from the plurality of pixels; and an analog/digital (A/D) converter configured to perform A/D conversion on the analog voltage signal from the analog memory. The plurality of pixels includes N pixels configured to simultaneously output analog voltage signals to the analog memory. The A/D converter includes (N?1) or less A/D converters configured to perform A/D conversion on the analog voltage signals that have been simultaneously output from the N pixels and stored in the analog memory.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: November 9, 2021
    Assignee: Ricoh Company, Ltd.
    Inventor: Yuuya Miyoshi
  • Patent number: 11162987
    Abstract: A method for separating spectrums of an input signal having a first spectrum and a second spectrum by mixing the input signal at a first mixer with a first frequency to obtain a first mixed signal; mixing the input signal at a second mixer with second frequency to obtain a second mixed signal; displacing the first mixed signal and/or the second mixed signal up and down by the difference of the first and second frequency obtaining at least one lower auxiliary signal and at least one upper auxiliary signal, respectively; and extracting the first spectrum and/or the second spectrum using the lower auxiliary signal and/or the upper auxiliary signal as well as the first mixed signal and/or the second mixed signal. Further, measurement devices for separating spectrums are shown.
    Type: Grant
    Filed: August 20, 2018
    Date of Patent: November 2, 2021
    Assignee: Rohde & Schwarz GmbH & Co. KG
    Inventors: Matthias Ruengeler, Gregor Feldhaus
  • Patent number: 11025459
    Abstract: Systems and methods for automatic level control (ALC) are provided. In one embodiment, an ALC system for communications signals comprises: a multi-threshold programmable ALC controller; and at least one signal path that includes: a digital step attenuator configured to receive an analog communications signal and attenuate the analog communications signal in response to an attenuation adjustment signal from the ALC controller; and an analog-to-digital converter configured to receive the analog communications signal as attenuated by the digital step attenuator and generate samples of the attenuated analog communications signal, wherein the ALC controller receives the samples. The ALC controller comprises a plurality of clip detectors that function in parallel. Each of the clip detectors are programmed with a respective amplitude and time threshold.
    Type: Grant
    Filed: July 21, 2020
    Date of Patent: June 1, 2021
    Assignee: CommScope Technologies LLC
    Inventors: Marco Parrucci, Enrico Maria Fabbri, Samuele Brighenti
  • Patent number: 10852408
    Abstract: A frequency-modulated continuous-wave (FMCW) radar system for level or distance measurement in which a frequency modulated signal to be transmitted to a target is mixed with an echo signal from the target to produce a beat signal that passes through an analog filter before being digitized and processed in a digital processor to determine the level or distance to be measured, where a test signal is generated by a signal generator, and a switch is controlled to connect the beat signal or the test signal to the analog filter, the signal generator generates the test signal as a broadband signal having a periodic waveform, e.g., a square wave, and the digital processor calculates a spectrum of the digitized filtered test signal by Fast Fourier Transform and generates a fault signal if the spectrum differs from a reference spectrum by a predetermined amount to allow for failure detection.
    Type: Grant
    Filed: January 20, 2016
    Date of Patent: December 1, 2020
    Assignee: Siemens Aktiengesellschaft
    Inventors: Alan Aslett, Johannes Theodorus Cornelis Duivenvoorden, Jing Liu, Mihai-Gabriel Serban
  • Patent number: 10695907
    Abstract: Methods, apparatus, systems, and articles of manufacture for monitoring robot health in manufacturing environments are described herein. An example system, to monitor health of a robot in a semiconductor wafer manufacturing facility, includes a sensor coupled to the robot. The sensor is to obtain a vibration signal representative of vibration of the robot. The example system also includes a health monitor extract a feature from the vibration signal, compare the feature to a threshold, and, in response to determining the feature satisfies the threshold, transmit an alert.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: June 30, 2020
    Assignee: Intel Corporation
    Inventors: Rita Chattopadhyay, Mruthunjaya Chetty, Jeffrey Davis, Stephanie Cope, Xiaozhong Ji
  • Patent number: 10536576
    Abstract: A test device for measuring load coils in a network using a pseudorandom binary sequence (PRBS) based technique is disclosed. The test device may comprise a transmitter to transmit a plurality of test signals at a test point in a network. The test device may comprise a receiver to receive a plurality of response signals at the test point. The test device may also comprise a processor to analyze the plurality of response signals and perform at least one load coil measurement. The processor may achieve this by applying a transformation calculation to generate a plurality of terms of the transformation calculation simultaneously, converting the plurality of terms of the transformation calculation into a plurality of impedances, converting the plurality of impedances into polynomials using a conversion technique, analyzing the polynomials for poles and zeros, and estimating at least one load coil measurement based on the poles and zeros of the polynomials.
    Type: Grant
    Filed: July 5, 2018
    Date of Patent: January 14, 2020
    Assignee: VIAVI SOLUTIONS INC.
    Inventors: Gerald Gaboury, John Handwork
  • Patent number: 10228401
    Abstract: The present invention relates to apparatus (10) for determining a contribution of at least one grid subsystem of plural grid subsystems to oscillation in angle or grid oscillation in an electrical grid (12). The apparatus (10) is configured to receive a first quantity which corresponds to oscillation in angle at a first grid subsystem (14). The apparatus (10) is also configured to receive a second quantity which corresponds to oscillation in angle at a second grid subsystem (16). The apparatus (10) comprises a processor (32) which is operative to determine a contribution of at least one of the first and second grid subsystems to oscillation in angle or grid oscillation with the contribution being determined in dependence on a phase relationship between the first and second quantities.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: March 12, 2019
    Assignee: PSYMETRIX LIMITED
    Inventors: Douglas Wilson, Natheer Al-Ashwal
  • Patent number: 10142521
    Abstract: Disclosed is a method that includes receiving an audio video stream, decoding the audio video stream to yield decoded video and decoded audio, transmitting the decoded video on a video cable to a display, transmitting a signal, such as, for example, a signal on an audio channel of the video cable, identifying an impulse response based on a received signal responsive to the transmitting of the signal, identifying a delay amount based on the impulse response and transmitting the decoded audio to a loudspeaker according to the delay amount. The cable can include an HDMI cable with the audio return channel (ARC) capability.
    Type: Grant
    Filed: March 22, 2017
    Date of Patent: November 27, 2018
    Assignee: CISCO TECHNOLOGY, INC.
    Inventors: Bjørn Winsvold, Lennart Burenius
  • Patent number: 10003310
    Abstract: In an RF transmitter, a digital predistortion circuit receives a sequence of input sample blocks, and performs a digital predistortion process to produce a predistorted output signal. The digital predistortion process includes selecting a set of predistortion coefficients for an input sample block from a plurality of different sets of predistortion coefficients. Each of the plurality of different sets of predistortion coefficients is associated with a different combination of one of a plurality of time slices within a radio frame and one of a plurality of power ranges. The selected set of predistortion coefficients is associated with a time slice within which the input sample block is positioned and a power range calculated for the input sample block based on block power statistics of the sample block. The process also includes applying the selected set of predistortion coefficients to the input sample block to produce the predistorted output signal.
    Type: Grant
    Filed: December 7, 2016
    Date of Patent: June 19, 2018
    Assignee: NXP USA, INC.
    Inventors: Mir Adeel Masood, Peter Zahariev Rashev, Jayakrishnan Cheriyath Mundarath
  • Patent number: 9812141
    Abstract: In encoding, pitch periods for time series signals in a predetermined time interval are calculated, and a code corresponding thereto is output. In that encoding, the resolutions for expressing the pitch periods and/or a pitch period encoding mode are switched according to whether an index indicating a periodicity and/or stationarity level of the time series signals satisfies a condition indicating high or low in periodicity and/or stationarity. In that decoding, according to whether an index indicating a periodicity and/or stationarity level, the index being included in or obtained from an input code corresponding to the predetermined time interval, satisfies a condition indicating high periodicity and/or stationarity, a decoding mode for a code, included in the input code, corresponding to pitch periods is switched to decode the code corresponding to the pitch periods to obtain the pitch periods corresponding to the predetermined time interval.
    Type: Grant
    Filed: January 7, 2011
    Date of Patent: November 7, 2017
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takehiro Moriya, Noboru Harada, Yutaka Kamamoto
  • Patent number: 9767072
    Abstract: Methods for determining the transfer function of a signal-processing system that do not require a known input signal. The methods are based on two representations 1(x) and I2(x) of an object, which the system has produced from differently scaled input signals originating from the object, or from a representation I1(x) of a first object and from a representation I2(x) of an object that is geometrically similar thereto but has been scaled differently. The representations are either given or are produced at the start of the method. According to the invention, the representations are transformed into a working space, and sections that relate to the same region of the object are selected in each case. The quotient of the functions corresponding to these two sections in the working space from which the unknown input signal comes makes it possible to clearly determine the transfer function sought. Various methods are indicated for this determination.
    Type: Grant
    Filed: April 21, 2012
    Date of Patent: September 19, 2017
    Assignee: Forschungszentrum Juelich GmbH
    Inventor: Andreas Thust
  • Patent number: 9759751
    Abstract: In one embodiment, a system and method perform a spectral analysis in a power measurement system to determine the total harmonic distortion (“THD”) in a power signal by correlating one or more THD calculation parameters to a sensed period of a voltage input signal. In at least one embodiment, the one or more THD calculation parameters are a number of samples of a voltage, current, or voltage and current components of the power signal that correlate to the sensed period. Because, for example, the period of the power signal can vary or the clock frequency can drift over time, the power measurement system correlates the number of samples with the period and, thus, varies the count of samples over which THD is calculated when the period varies. By correlating the samples with the period, the samples more closely represent a period of the sampled component of the power signal.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: September 12, 2017
    Assignee: Cirrus Logic, Inc.
    Inventor: Shruti Sethi
  • Patent number: 9680493
    Abstract: A signal monitoring system includes a splitter circuit, a single-bit channel circuit, a multi-bit channel circuit, and a frequency processor circuit. The splitter circuit splits a first analog signal into second and third analog signals. The single-bit channel circuit samples the second analog signal at a sampling rate that is greater than or equal to a Nyquist rate of the second analog signal to generate a first digital signal. The multi-bit channel circuit under-samples the third analog signal at a sampling rate that is less than a Nyquist rate of the third analog signal to generate second digital signals. The frequency processor circuit resolves a Nyquist zone ambiguity in the second digital signals using the first digital signal to generate an unambiguous output signal.
    Type: Grant
    Filed: September 21, 2016
    Date of Patent: June 13, 2017
    Assignee: Altera Corporation
    Inventor: Dan Pritsker
  • Patent number: 9558154
    Abstract: A measuring device for suppressing an interference signal contains a mixer, an analog-digital converter, a scaling device and a substitution device. The mixer is embodied to mix a first signal with a first intermediate frequency and to mix a second signal with a second intermediate frequency. The analog-digital converter is embodied to digitize the first signal mixed with the first intermediate frequency to form a first test signal and to digitize the second signal mixed with the second intermediate frequency to form a second test signal is embodied to displace at least the first test signal and/or the second test signal in its frequency in such a manner that they provide a common mid-frequency. The substitution device is embodied to combine the first test signal and the second test signal with a removal of interference-signal peak-value regions which correspond to the interference signal, to form a combined test signal.
    Type: Grant
    Filed: May 3, 2012
    Date of Patent: January 31, 2017
    Assignee: Rohde & Schwarz GmbH & Co. KG
    Inventors: Gregor Feldhaus, Alexander Roth
  • Patent number: 9511969
    Abstract: A method includes designing probing signals for testing an alignment of actuators in a web manufacturing or processing system with measurements of a web of material being manufactured or processed by the system. The method also includes providing the probing signals during alignment testing to identify the alignment of the actuators with the measurements of the web. Designing the probing signals includes designing the probing signals based on both spatial and dynamic characteristics of the web manufacturing or processing system.
    Type: Grant
    Filed: March 28, 2012
    Date of Patent: December 6, 2016
    Assignee: Honeywell Limited
    Inventors: Danlei Chu, Cristian Gheorghe
  • Patent number: 9316734
    Abstract: Wideband synthetic aperture radar (SAR) imaging. A probe transmits a signal through its aperture incident to an object located in a medium of interest remotely from the probe. The probe receives through the aperture a plurality of nonuniformly sampled reflected signals from the object as the probe moves in a measurement plane located a predetermined distance from the object. A processor executes a SAR-based reconstruction algorithm to generate an image.
    Type: Grant
    Filed: October 21, 2013
    Date of Patent: April 19, 2016
    Assignee: The Curators of the University of Missouri
    Inventors: Joseph T. Case, Mohammad Tayeb Ghasr, Reza Zoughi
  • Patent number: 9234246
    Abstract: A decentralized load shedding device turns off a load in response to determining that an electric grid is approaching its maximum operating point. By turning off the load, demand on the electric grid is minimized thereby reducing the likelihood of blackouts. The device may be coupled to the load or may be incorporated into the load in one embodiment.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: January 12, 2016
    Assignee: Google Inc.
    Inventors: Benjamin Davis, Alexander Nelson Brooks
  • Patent number: 9065323
    Abstract: A grid-tie inverter includes a power circuit and a control circuit coupled to the power circuit. The power circuit has an input terminal for coupling to a DC power source and an output terminal for coupling to an AC power grid. The control circuit is configured to perturb an AC output current of the power circuit a first time and detect a first change in an AC output voltage of the power circuit without shutting down the power circuit, perturb the AC output current of the power circuit a second time and detect a second change in the AC output voltage of the power circuit, and shut down the power circuit in response to detecting at least the first change in the AC output voltage and the second change in the AC output voltage. Example embodiments and related methods of controlling grid-tied inverters are also disclosed.
    Type: Grant
    Filed: March 4, 2013
    Date of Patent: June 23, 2015
    Assignee: ASTEC INTERNATIONAL LIMITED
    Inventors: Vijay Gangadhar Phadke, Yancy Fontanilla Boncato
  • Patent number: 8981756
    Abstract: Systems and methods for an industrial I/O controller circuit for frequency input modules that measure the frequency of an electrical input signal using adaptive threshold voltage and/or adaptive hysteresis feedback are shown and described. The systems and methods provide advantages in that the I/O controller circuit can better distinguish between actual input pulses from the electrical input signal, as opposed to unwanted Electromagnetic Interference (EMI) induced input pulses. This maximizes the amount of EMI rejection, independent of the frequency of the moving machine, and results in less time to commission and adjust a sensor, fewer false frequency measurements and less system down time.
    Type: Grant
    Filed: April 11, 2012
    Date of Patent: March 17, 2015
    Assignee: Rockwell Automation Technologies, Inc.
    Inventor: Joseph G. Vazach
  • Patent number: 8896330
    Abstract: A method and apparatus for monitoring an AC line for impedance change. In one embodiment, the method, comprises superimposing a tone on an AC current coupled to the AC line, wherein the tone is a higher frequency than an AC voltage waveform on the AC line; applying a correlation over a sampled AC voltage waveform, obtained by sampling the AC voltage waveform, to generate a correlated signal; and determining whether at least one change in characteristic of the correlated signal occurs.
    Type: Grant
    Filed: June 1, 2012
    Date of Patent: November 25, 2014
    Assignee: Enphase Energy, Inc.
    Inventors: Andrew Barnes, Brian Acker
  • Patent number: 8878549
    Abstract: An AC impedance measuring device includes: a signal generator configured to provide a first signal on which a period signal is superimposed to a DUT; a Fourier transform unit configured to perform Fourier transform on current data and voltage data output from the DUT using a transformation window while sequentially shifting a start time of the transformation window, thereby obtaining a plurality of Fourier transform data strings of the voltage data and the current data; a difference sequence calculator configured to sequentially calculate a first difference sequence of the Fourier transform data strings of the voltage data and a second difference sequence of the Fourier transform data strings of the current data; and an impedance calculator configured to calculate an impedance of the DUT based on a ratio of the first difference sequence and the second difference sequence.
    Type: Grant
    Filed: March 15, 2011
    Date of Patent: November 4, 2014
    Assignee: Yokogawa Electric Corporation
    Inventors: Hirofumi Nakanishi, Shuhei Okada
  • Patent number: 8854029
    Abstract: A system and method for space control and remote monitoring is disclosed. According to one embodiment, a frequency modulated signal is emitted from a radioscopic device having an antenna. The frequency of the reflected signal from a target is compared with the emitted frequency modulated signal to obtain a low-frequency signal. The low-frequency signal is processed to form signal pulsations spectrum using a fast Fourier transform. Each spectrum frequency represents a distance to the target.
    Type: Grant
    Filed: January 9, 2012
    Date of Patent: October 7, 2014
    Assignee: Radical Development Holding S.A.
    Inventor: Kirill Mostov
  • Publication number: 20140167734
    Abstract: A method for detecting at least two amplitude-modulated transmitted signals contained in a received signal within the same frequency channel with respectively different frequency displacement determines from the received signal a modified received signal by means of a nonlinear signal processing. Following this, the spectrum of the modified received signal is determined by means of Fourier transform, and at least two transmitted signals contained in the received signal are detected if at least two first spectral lines each associated with carrier signals are significantly distinguishable within the determined spectrum from spectral components associated with noise signals and payload signals.
    Type: Application
    Filed: July 17, 2012
    Publication date: June 19, 2014
    Applicant: ROHDE & SCHWARZ GMBH & CO. KG
    Inventor: Thorben Detert
  • Patent number: 8744025
    Abstract: Methods, systems and other embodiments associated with pre-processing a signal for spectral analysis are presented. A system for pre-processing a digital input signal includes a digital down converter (DDC), an interpolator, and a series of down samplers. The DDC modulates the digital input signal to create a down converted signal. The interpolator re-samples the down converted signal to produce a re-sampled signal. The series of down samplers produces down sampled signals. The multiplexer selects one of the digital input signal, the down converted signal, and the down sampled signals and routes the selected signal to an output line.
    Type: Grant
    Filed: August 30, 2010
    Date of Patent: June 3, 2014
    Assignee: BAE Systems Information Solutions Inc.
    Inventors: Robert W. Lowdermilk, Dragan Vuletic, Fredric J. Harris, Michael Tammen
  • Patent number: 8674680
    Abstract: A method and device are provided for fast impedance measurement of a biological object having dynamically varying in time parameters, wherein a titlet shaped pulse is introduced into the object and a voltage response signal is measured and analyzed by a processing unit for estimating the impedance of the object. The titlet pulse has a start frequency substantially in one end of the frequency range of interest and a stop frequency substantially in the other end of the frequency range of interest and a duration of the titlet pulse is one cycle or less.
    Type: Grant
    Filed: October 25, 2010
    Date of Patent: March 18, 2014
    Assignee: Tallinn University of Technology OÜ Eliko Tehnoloogia Arenduskeskus
    Inventors: Mart Minn, Toivo Paavle, Raul Land, Paul Annus, Toomas Parve
  • Publication number: 20140028283
    Abstract: Methods and apparatus for using Fourier techniques to detect and isolate the fundamental frequency sweep of echolocation calls produced by bats, or of other narrow-band whistles as produced by other kinds of animals such as birds and whales. According to one example, a Fourier transform is applied on blocks of input samples to produce output frames, and a narrowband frequency modulated signal is detected and traced through the output frames. A filter is applied in each frame to attenuate frequencies above or below the narrowband signal, and an inverse Fourier transform is applied to produce an output signal. The resulting signal may then be analyzed with zero crossing techniques to measure the precise instantaneous frequency sweep.
    Type: Application
    Filed: July 26, 2012
    Publication date: January 30, 2014
    Inventor: Ian Agranat
  • Patent number: 8582675
    Abstract: A pre-channelized spectrum analyzer utilizes a channelizer as a preprocessor for parallel-configured low-resolution spectrum analyzers so as to perform as a high resolution spectrum analyzer. The pre-channelized spectrum analyzer has a polyphase filter that channelizes a signal input and an IFFT that generates filter bank outputs derived from the channelized signal. Spectrum analyzers are in communications with the filter bank outputs so as to generate a spectral decomposition of a subset of those outputs. The spectrum analyzers each perform a window and an FFT function on a corresponding one of the filter bank subset.
    Type: Grant
    Filed: June 1, 2011
    Date of Patent: November 12, 2013
    Inventor: Fredric J. Harris
  • Patent number: 8514919
    Abstract: Systems and other embodiments associated with synthetic instrumentation are presented. A reconfigurable synthetic instrumentation unit comprises an input module, with dual input/output ports and conditioning logic to condition an input signal. An RF down converter selectively down converts the conditioned input signal. A sampled RF down converter selectively samples the conditioned input signal. A pair of narrowband A/D converters are configured to convert one of the conditioned signal, the down converted signal and the sampled signal to produce a narrowband digital signal. A pair of broadband A/D converters convert at least one of the conditioned signal, the down converted signal and the sampled signal to produce a broadband digital signal. Signal processing logic selectively performs digital signal processing on the broadband digital signal or the narrow band digital signal.
    Type: Grant
    Filed: August 25, 2010
    Date of Patent: August 20, 2013
    Assignee: BAE Systems National Security Solutions Inc.
    Inventors: Anthony J. Estrada, Dana C. Ford, Tae S. Kim, Robert W. Lowdermilk, Dragan Vuletic
  • Publication number: 20130083819
    Abstract: A method for operating an arc furnace, an oscillation measurement device for an arc electrode, and a configuration for the arc furnace are described. Using simple measures for operating the arc furnace, it is possible to carry out, in a particularly safe and productive manner, an oscillation measurement on the at least one arc electrode. On the basis of which the operation of the configuration for the arc furnace can be controlled with regard to the mechanical and/or electrical operating parameters.
    Type: Application
    Filed: November 26, 2012
    Publication date: April 4, 2013
    Applicant: SGL CARBON SE
    Inventor: SGL CARBON SE
  • Patent number: 8244196
    Abstract: A method is provided for estimating a Noise and Interference (NI) power in a ranging code reception apparatus in a communication system. The method includes generating S correlation values by calculating correlations between L ranging subcarriers received at a ranging code reception apparatus and L elements included in each of S ranging codes available in the ranging code reception apparatus, detecting N reception-desired ranging codes that the ranging code reception apparatus desires to receive, among the S ranging codes, using the S correlation values, and selecting M remaining ranging codes among (S-N) ranging codes obtained by removing the N reception-desired ranging codes from the S ranging codes, and estimating a first NI power using correlation values for the M remaining ranging codes.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: August 14, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ha-Young Yang, Sung-Kwon Jo
  • Publication number: 20120105048
    Abstract: A system and method for space control and remote monitoring is disclosed. According to one embodiment, a frequency modulated signal is emitted from a radioscopic device having an antenna. The frequency of the reflected signal from a target is compared with the emitted frequency modulated signal to obtain a low-frequency signal. The low-frequency signal is processed to form signal pulsations spectrum using a fast Fourier transform. Each spectrum frequency represents a distance to the target.
    Type: Application
    Filed: January 9, 2012
    Publication date: May 3, 2012
    Inventor: KIRILL MOSTOV
  • Patent number: 8169172
    Abstract: A variable speed drive for an electric motor has an inverter for receiving pulse width modulation controls. The inverter communicates power signals to a poly-phase electrical motor. A resolver communicates signals from the poly-phase motor back to a motor control. The motor control includes a speed control, a field-oriented control, and a pulse width modulation drive for driving the inverter. The resolver is connected to the speed control and to the field-oriented control, and further communicates with a synchronous compensator. The synchronous compensator is configured to drive the harmonic content at a target frequency or frequencies in a selected signal towards zero over time.
    Type: Grant
    Filed: May 3, 2010
    Date of Patent: May 1, 2012
    Assignee: Hamilton Sundstrand Corporation
    Inventors: Albert L. Markunas, James J. Wrobel
  • Patent number: 8120355
    Abstract: A magnetic anomaly detector includes a magnetically active device which produces analog signals in response to magnetic fields. The analog signals are time quantized and then discrete-time differentiated. The differentiated signals are applied to a low-pass filter. The filtered signals are Fourier transformed into an amplitude-frequency spectrum. An error detector compares at least one reference amplitude-frequency spectrum with the reference spectrum to identify the presence or absence of a magnetic anomaly. The resulting error is displayed on a monitor or operates an alarm.
    Type: Grant
    Filed: May 27, 2009
    Date of Patent: February 21, 2012
    Assignee: Lockheed Martin Corporation
    Inventor: John B. Stetson
  • Patent number: 8115472
    Abstract: A system and method for space control and remote monitoring is disclosed. According to one embodiment, a frequency modulated signal is emitted from a radioscopic device having an antenna. The frequency of the reflected signal from a target is compared with the emitted frequency modulated signal to obtain a low-frequency signal. The low-frequency signal is processed to form signal pulsations spectrum using a fast Fourier transform. Each spectrum frequency represents a distance to the target.
    Type: Grant
    Filed: October 24, 2008
    Date of Patent: February 14, 2012
    Assignee: Kirsen Technologies Corporation Inc.
    Inventor: Kirill Mostov
  • Patent number: 8035369
    Abstract: The subject matter of the invention is a method for detecting an isolated network for an inverter (2) carrying a converter voltage that is adapted for connection in parallel with a grid (5) having a mains frequency and electric loads and that is decoupled from the grid (5) by a choke (3), a test signal being superimposed upon the converter voltage at a test frequency the frequency of which is smaller than the mains frequency, the amplitude of the test signal being much smaller than the nominal voltage amplitude of the mains voltage on the one side but still just large enough on the other side for changes in reactive power to be detectable as a result of the test signal, a reactive power share being determined, which oscillates with the test frequency, this share not being allowed to fall below an imposed minimum for an isolated operation to be reliably excluded.
    Type: Grant
    Filed: June 9, 2008
    Date of Patent: October 11, 2011
    Assignee: SMA Solar Technology AG
    Inventors: Michael Strnad, Neidhardt Bechtel, Christian Hardt
  • Patent number: 7994410
    Abstract: A method is provided to compare recordings that includes providing a list of a plurality of recordings and selecting at least a first recording and a second recording from the plurality of recordings. The first recording and the second recording have predetermined lengths. The method also includes selecting a first portion of the first recording, identifying a second portion of the second recording based on the first portion, and comparing the first portion to the second portion. When the entire length of the recording is selected as the first portion, the entire length of the second recording can be identified as the second portion. Identifying a second portion may also include normalizing it to the first portion. Also, identifying the second portion can include translating the first portion into a wave-form, searching the second recording for another wave-form similar to the translated wave-form, and matching the translated wave form with the similar wave-form.
    Type: Grant
    Filed: October 22, 2008
    Date of Patent: August 9, 2011
    Assignee: Classical Archives, LLC
    Inventor: Pierre R. Schwob
  • Patent number: 7930119
    Abstract: A method is disclosed for analyzing an AC voltage signal with a transformation which transforms the signal from a representation in the time-domain to a representation in the frequency-domain. This transformation can be a fast Fourier transform, a discrete Fourier transform or a Laplace transform. By selecting a second higher sampling frequency which is an integer multiple of a first sampling frequency, the zero crossings of the AC voltage signal can be accurately determined.
    Type: Grant
    Filed: January 8, 2008
    Date of Patent: April 19, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventor: Robert Bösnecker
  • Patent number: 7845937
    Abstract: A specific electrode arrangement for a burner already exists with which the flame of the burner is influenced by using electrical fields, whereby these electrical fields pass through only areas of the flame in which a stabilizing and pollutant-reducing action occurs. According to at least one embodiment of the invention, the electrodes used to this end simultaneously serve both as probes for detecting flame properties as well as active field electrodes for influencing the flame properties. The probe signals can react to the voltage applied in an inertia-free manner to the electrodes without the involvement of mechanical elements. According to the associated device equipped with a burner and associated electrodes and with a power supply unit, the power supply unit furnishes a voltage that varies over time, and at least one measuring transducer exists that detects the current generated in the flame by the voltage between both electrodes and provides feedback to the power supply unit after amplification.
    Type: Grant
    Filed: December 19, 2005
    Date of Patent: December 7, 2010
    Assignee: Siemens Aktiengesellschaft
    Inventors: Thomas Hammer, Günter Lins, Jobst Verleger
  • Publication number: 20100271002
    Abstract: A discharge amount measuring device includes a power source, first and second sensors, a calibration wire, and a measuring portion. The power source applies a voltage to a coil of a rotational electric machine. The first sensor detects a current flowing through the coil. The calibration wire has an end connected to the coil. The second sensor detects a current flowing through the calibration wire. The measuring portion forms a calibration line based on a first waveform detected by the first sensor and a second waveform detected by the second sensor. The measuring portion calculates a discharge amount based on the calibration line.
    Type: Application
    Filed: April 27, 2010
    Publication date: October 28, 2010
    Applicants: NIPPON SOKEN, INC., DENSO CORPORATION
    Inventors: Toru Wakimoto, Yoshimitsu Takahashi, Shinji Kouda
  • Patent number: 7795858
    Abstract: In one embodiment, a spectral map for performing nonlinear calibration of a signal path is developed by 1) identifying a set of frequency locations for a set of particular output signal spurs that result from applying one-tone and two-tone input signals covering a bandwidth of interest to the signal path; 2) developing, based on the set of frequency locations, a spectral map for predistorting, in the frequency domain, signals that are applied to, or received from, the signal path in the time domain; and 3) saving the spectral map for performing nonlinear calibration of the signal path.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: September 14, 2010
    Assignee: Agilent Technologies, Inc.
    Inventors: Nicholas B. Tufillaro, Robert E. Jewett
  • Publication number: 20100176790
    Abstract: A testing method for a wireless receiver includes processing a test signal to generate an in-phase and a quadrature signal, performing a Fourier transform process to the in-phase signal and the quadrature signal to generate a first transformation result and a second transformation result, and displaying the first transformation result and the second transformation result by means of graphic, to generate a test result corresponding to the test signal.
    Type: Application
    Filed: April 19, 2009
    Publication date: July 15, 2010
    Inventor: Chu-Hsin Tsao
  • Publication number: 20100109639
    Abstract: A frequency spectrum analysis system includes a control platform, a driver, and a controlled system. The control platform includes a first transmission device. The driver includes a second transmission device, a signal source, and a data logger. The first transmission device is connected to the second transmission device. The second transmission device is connected to the signal source. The signal source is connected to the data logger and the controlled system. The data logger is connected to the controlled system and the first transmission device.
    Type: Application
    Filed: December 15, 2008
    Publication date: May 6, 2010
    Applicant: FOXNUM TECHNOLOGY CO., LTD.
    Inventors: SHEN-AN CHEN, YOU-REN LIN, RONG-CONG HUNG, SHIH-CHANG CHEN, RONG-HWANG HORNG, YAW-SHEN LAI
  • Patent number: 7696761
    Abstract: The invention provides a spectrum analyzing method, a distortion detector and a distortion compensation amplifying device for performing time/frequency conversion processing at high speed, and reducing a convergent time of a compensation coefficient. The distortion detector for detecting distortion in a frequency area with respect to an input signal includes a time window processing section for multiplying the input signal by a time window; an averaging processing section for averaging an output of the time window processing section; an FFT processing section for converting an output of the averaging processing section from a time area to a frequency area; and a distortion extracting section for extracting a distortion component from an output of the FFT processing section.
    Type: Grant
    Filed: August 10, 2006
    Date of Patent: April 13, 2010
    Assignee: Hitachi Kokusai Electric, Inc.
    Inventors: Tetsuhiko Miyatani, Masashi Naito, Naoki Hongo, Takashi Okazaki
  • Patent number: 7613580
    Abstract: A system that generates an electromagnetic interference (EMI) fingerprint for a computer system is presented. During operation, the system executes a load script on the computer system, wherein the load script includes a specified sequence of operations. Next, the system receives EMI signals generated by the computer system while executing the load script. The system then generates the EMI fingerprint from the received EMI signals.
    Type: Grant
    Filed: April 12, 2007
    Date of Patent: November 3, 2009
    Assignee: Sun Microsystems, Inc.
    Inventors: Kenny C. Gross, Aleksey M. Urmanov, Ramakrishna C. Dhanekula
  • Patent number: 7613974
    Abstract: This invention relates to fault detection in electrical circuits. The invention provides a method and apparatus for testing an input circuit by generating a periodic test signal having a predetermined phase and a predetermined amplitude; summing the test signal and an input signal to provide a summed signal; processing the summed signal to provide an output signal; generating an extracted test signal from the output signal; comparing the extracted test signal with a reference signal representing said periodic test signal; generating an error signal in dependence upon the result of said comparing step. The invention also provides a method and apparatus for testing a plurality of adjacent input circuits.
    Type: Grant
    Filed: March 21, 2007
    Date of Patent: November 3, 2009
    Assignee: ICS Triplex Technology Limited
    Inventor: Thomas Bruce Meagher
  • Patent number: 7613576
    Abstract: A system that monitors electromagnetic interference (EMI) signals to facilitate proactive fault monitoring in a computer system is presented. During operation, the system receives EMI signals from one or more antennas located in close proximity to the computer system. The system then analyzes the received signals to proactively detect anomalies during operation of the computer system.
    Type: Grant
    Filed: April 12, 2007
    Date of Patent: November 3, 2009
    Assignee: Sun Microsystems, Inc.
    Inventors: Kenny C. Gross, Aleksey M. Urmanov, Ramakrishna C. Dhanekula, Steven F. Zwinger
  • Publication number: 20090206842
    Abstract: Some embodiments of the present invention provide a system that determines whether a cooling device in a computer system is responsive to control signals. During operation of the computer system, a control signal is sent to the cooling device. Next, a response of the computer system to the control signal is measured, wherein the response includes a temperature profile. The frequency content of the control signal is then compared to the frequency content of the temperature profile to determine whether the cooling device is responsive to the control signal.
    Type: Application
    Filed: February 14, 2008
    Publication date: August 20, 2009
    Applicant: SUN MICROSYSTEMS, INC.
    Inventors: Kalyanaraman Vaidyanathan, Kenny C. Gross, Aleksey M. Urmanov
  • Publication number: 20090153132
    Abstract: In one embodiment, a spectral map for performing nonlinear calibration of a signal path is developed by 1) identifying a set of frequency locations for a set of particular output signal spurs that result from applying one-tone and two-tone input signals covering a bandwidth of interest to the signal path; 2) developing, based on the set of frequency locations, a spectral map for predistorting, in the frequency domain, signals that are applied to, or received from, the signal path in the time domain; and 3) saving the spectral map for performing nonlinear calibration of the signal path.
    Type: Application
    Filed: December 18, 2007
    Publication date: June 18, 2009
    Inventors: Nicholas B. Tufillaro, Robert E. Jewett
  • Patent number: 7490013
    Abstract: Electric power grids are usually constantly monitored for AC frequency. The monitoring of the AC frequency, however, usually does not reveal information that would indicate impending failure in the power grid. This document describes several techniques for detecting impending failure in the power grid by examining line data in the frequency domain.
    Type: Grant
    Filed: December 8, 2004
    Date of Patent: February 10, 2009
    Assignee: OSlsoft, Inc.
    Inventor: Charles H. Wells