Using Fourier Method Patents (Class 702/77)
  • Publication number: 20110288801
    Abstract: A method of estimating the time of flight of a burst signal includes: receiving the burst signal; determining the slope of the phase characteristic of the Fourier transform of the received burst signal; and estimating the time-of-flight of the burst signal from the slope of the phase characteristic of the Fourier transform of the received burst signal.
    Type: Application
    Filed: May 18, 2010
    Publication date: November 24, 2011
    Applicant: Avago Technologies Wireless IP (Singapore) Pte. Ltd.
    Inventor: Osvaldo BUCCAFUSCA
  • Publication number: 20110285518
    Abstract: A method and system for detecting the existence of rumble strips on a roadway by a vehicle. Wheel speed data is obtained from a wheel speed sensor, and frequency-based analysis is then performed on the wheel speed data. The presence of a rumble strip can then be detected based on the outcome of the frequency-based analysis. The wheel speed data can be modified before conversion to the frequency domain to reduce wheel-induced cyclic variations in wheel speed. The frequency-based analysis can use an FFT and a peak detection method that analyzes one or more peaks in the FFT data to determine if any are indicative of the presence of a rumble strip. The method can be carried out automatically in real time and used to alert the driver of the detection of the rumble strip.
    Type: Application
    Filed: May 19, 2010
    Publication date: November 24, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Timothy J. Gordon, Zeev Bareket, Mark Gilbert, Michael R. Hagan
  • Patent number: 8050880
    Abstract: One or more embodiments of the present invention relates to an iterative method for generating an almost-constant, nearly constant, or substantially-constant envelope time signal with prescribed Fourier transform magnitude in the frequency domain, and a constant envelope time signal whose Fourier transform magnitude closely matches the prescribed Fourier transform magnitude in the frequency domain. Different starting points for the iterative algorithm give rise to different solutions and their accuracy can be adjusted using a monotonic error criterion presented here.
    Type: Grant
    Filed: October 28, 2008
    Date of Patent: November 1, 2011
    Assignee: C & P Technologies, Inc.
    Inventors: Unnikrishna Sreedharan Pillai, Ke Yong Li
  • Patent number: 8044670
    Abstract: An apparatus for determining a resonant frequency of a wind turbine tower is provided. The apparatus includes a processing unit configured to receive an acceleration measurement value, the acceleration measurement value representative of the acceleration of the wind turbine tower in the direction parallel to a rotor rotational axis of the wind turbine and/or in the direction perpendicular to both the rotor rotational axis and the tower axis of the wind turbine. The apparatus includes a memory configured to store a series of acceleration measurement values, and the processing unit includes a Fourier transform module configured to calculate a spectral vector based on calculating a convolution-based fast Fourier transform of the series of acceleration measurement values, and includes a resonant frequency calculation module configured to calculate the tower resonant frequency based on the calculated spectral vector.
    Type: Grant
    Filed: March 12, 2009
    Date of Patent: October 25, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventors: Martin Bjerge, Per Egedal
  • Publication number: 20110251804
    Abstract: A method of isolating a frequency in a rotating machine having at least one sensor includes receiving, from the at least one sensor, a sensor signal that includes at least one frequency, converting the sensor signal to a digital vibration signal, modifying the vibration signal to generate an envelope signal, synchronously oversampling the envelope signal to generate a synchronous envelope signal, and transforming the synchronous envelope signal into a frequency spectrum to isolate the frequency.
    Type: Application
    Filed: April 13, 2010
    Publication date: October 13, 2011
    Inventors: Dustin Delany Hess, Charles Terrance Hatch
  • Patent number: 8032322
    Abstract: An apparatus is provided for measuring a frequency-domain optical coherence tomography power spectrum from a sample. The apparatus includes a broadband light source, an optical spectrum analyzer, and a partially reflective element optically coupled to the light source, to the optical spectrum analyzer, and to the sample. A first portion of light from the light source is reflected by the partially reflective element and propagates to the optical spectrum analyzer. A second portion of light from the light source propagating through the partially reflective element, impinging the sample, reflecting from the sample, and propagating to the optical spectrum analyzer.
    Type: Grant
    Filed: February 17, 2009
    Date of Patent: October 4, 2011
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Aydogan Ozcan, Michel J. F. Digonnet, Gordon S. Kino
  • Patent number: 8023575
    Abstract: A wireless communications apparatus that it is useable as a spectrum analyzer and as a wireless receiver. The wireless communications apparatus has a radio circuit that is configured to receive EM radiation. Signal processing logic receives signals from the radio circuit based on the EM radiation. The signal processing logic has a receiver operational mode that processes the signals in accordance with a communication protocol and outputs data encoded in the signals to a host processor. The signal processing logic has a spectrum analyzer operational mode that generates frequency domain data and passes the frequency domain data to the host processor. The frequency domain data describe strength versus frequency of the EM radiation. The host processes the data in accordance with the configuration currently in use. Therefore, the wireless communications apparatus operates as a receiver in one operational mode and as a real-time spectrum analyzer in another operational mode.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: September 20, 2011
    Assignee: Bandspeed, Inc.
    Inventors: Ben Jones, Ming Ding, John “Jack” Morton
  • Patent number: 8014965
    Abstract: A spectrometric system has a primary channel with a signal waveform and a reference channel with a signal waveform. A digital representation of the primary signal waveform and a digital representation of the reference signal waveform to provide a digital output representing the primary signal at datum points synchronized with the reference signal are processed by computing the Fourier transform of the primary signal waveform and using a fast reverse non-uniform discrete Fourier Transform technique to compute the reverse non-uniform discrete Fourier transform of the Fourier transform of the primary signal waveform to provide the digital output representing the primary signal at datum points synchronized with the reference signal.
    Type: Grant
    Filed: February 21, 2007
    Date of Patent: September 6, 2011
    Assignee: ABB Bomen
    Inventors: Raphaël Desbiens, Henry L. Buijs
  • Patent number: 7987060
    Abstract: A method of processing Fourier Transform Mass Spectrometry (FTMS) data includes performing a Fourier Transform of a part of a time domain transient and identifying from that transformed data signal peaks representative of the presence of ions. After peak identification, the full transient is then transformed, and the peaks identified in the partial transient transform are used to locate true peaks in the transformed full transient. The number of ‘false’ peaks resulting from random noise has been found to correlate to the resolution, so that using a partial transient to identify true peaks reduces the risk of false peaks being included; nevertheless this information can then be applied to the full data set when transformed. As an alternative, different parts of the full data set can be transformed and then correlated; because any noise will be random, false peaks should occur at different places in the two partial transforms.
    Type: Grant
    Filed: November 23, 2005
    Date of Patent: July 26, 2011
    Assignee: Thermo Finnigan LLC
    Inventors: Oliver Lange, Michael W. Senko
  • Publication number: 20110172974
    Abstract: A system for via structure measurement is disclosed. The system comprises a reflectometer, a simulation unit and a comparing unit. The reflectometer is configured to collect a measured diffraction spectrum of at least a via. The simulation unit is configured to provide simulated diffraction spectrums of the at least a via. The comparing unit is configured to determine at least a depth and at least a bottom profile of the at least a via by comparing the collected diffraction spectrum and the simulated diffraction spectrums.
    Type: Application
    Filed: March 17, 2010
    Publication date: July 14, 2011
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Yi Sha KU, Wei Te Hsu, Hsiu Lan Pang, Deh Ming Shyu
  • Publication number: 20110166814
    Abstract: A method for determining characteristics of a multi-material object is provided. The method includes determining an electric element matrix representing the multi-material object. The electric element matrix is pre-multiplied by a first mathematical transformation matrix to obtain a first transformed electric element matrix. The first transformed electric element matrix is post-multiplied with a second mathematical transformation matrix to obtain a second transformed electric element matrix. The method further includes determining the characteristics of the multi-material object based on the second transformed electric element matrix.
    Type: Application
    Filed: January 5, 2010
    Publication date: July 7, 2011
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Sakethraman Mahalingam, Arijit Banerjee, Wrichik Basu, Harish Kumar Pillai
  • Patent number: 7949495
    Abstract: A process variable transmitter with diagnostics based on power spectral density (PSD) analysis of a process variable sensor signal is provided. In one embodiment, the process variable transmitter is a pressure transmitter and the diagnostics are used to diagnose impulse line obstruction or impending obstruction. Other diagnostics are also useful such as diagnosing primary element degradation. The sensor signal is digitized and the digitized signal is transferred into the frequency domain. The power of the frequencies on the sensor signal is examined to provide the enhanced diagnostics. In one aspect diagnostics are generated directly with the sensor PSD data. In another aspect, the PSD analysis is used to tune a filter in order to enhance traditional diagnostic algorithms.
    Type: Grant
    Filed: August 17, 2005
    Date of Patent: May 24, 2011
    Assignee: Rosemount, Inc.
    Inventors: David E. Wiklund, Kadir Kavaklioglu, John P. Miller, Ross C. Lamothe, Evren Eryurek
  • 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
  • Publication number: 20110080197
    Abstract: A method for measuring characteristics of a power line signal having a fundamental frequency is provided. The method includes estimating the fundamental frequency of the power line signal, and generating a sampling clock that is substantially synchronized to the estimated fundamental power line frequency. The power line signal is sampled with the substantially synchronized sampling clock to generate data samples that include one or more substantially complete cycles of the power line signal. The data samples are processed to detect zero crossings of the power line signal, and the detected zero crossings are used to calculate an r.m.s. voltage of the power line signal measured over one full cycle, commencing at a zero crossing, and refreshed each half-cycle. Other aspects are also provided.
    Type: Application
    Filed: October 4, 2010
    Publication date: April 7, 2011
    Applicant: Siemens Industry, Inc.
    Inventors: Chun Fan, Paul Terricciano
  • Publication number: 20110077887
    Abstract: Light to be measured L and sampling pulse light LSP are each split into M beams, and a time delay of 0, T, 2T, . . . , (M?1)T is given to each of the M-split sampling pulse light beams. The M-split light beams to be measured are then respectively multiplexed with M optical 90-degree hybrids, and M electrical field amplitudes per time T are determined for the light beam to be measured, based on M sets of output currents received at a balance light receiving element that receives light emitted from each of the optical 90-degree hybrids. The amplitudes of the respective wavelength optical signals contained in the light beam to be measured are calculated through Fourier transformations of the field electrical amplitudes. Pulsed light with a spectral width that covers the total frequency bandwidth of the light to be measured is used as the sampling pulse light.
    Type: Application
    Filed: May 14, 2009
    Publication date: March 31, 2011
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Fumihiko Ito, Keiji Okamoto
  • Publication number: 20110060525
    Abstract: A moored buoy floating at the ocean surface and anchored to the seafloor precisely measures acceleration, pitch, roll, and Earth's magnetic flux field of the buoy over a limited sampling period.
    Type: Application
    Filed: September 6, 2009
    Publication date: March 10, 2011
    Inventors: Chung-Chu Teng, Rodney Riley, Richard Bouchard
  • Patent number: 7899963
    Abstract: A method and an apparatus for allocating configuration inputs of a microcontroller, the apparatus being embodied in such a way that at each configuration input, one signal state of at least two possible signal states is to be set, wherein there is connected to each configuration input one respective energy source that can assume at least two states, in order to set the at least two signal states at each configuration input, a setting arrangement being provided with which the states of each energy source are controlled in such a way that the predefined signal state exists for each configuration input.
    Type: Grant
    Filed: July 21, 2005
    Date of Patent: March 1, 2011
    Assignee: Robert Bosch GmbH
    Inventor: Carsten Mitter
  • Patent number: 7899645
    Abstract: Methods are provided for analyzing characteristics of fluids in the context of an acoustic ejection system. Such a system has a controller, an acoustic radiation generator, and a coupling medium coupling the radiation to a reservoir holding fluid. The methods can use acoustic radiation to both perturb a surface of the fluid in the reservoir and analyze the effect of the perturbation. The methods may use information about prior fluids. The methods of the invention can determine physical characteristics such as speed of sound and viscosity. The methods also include ways to determine a level of acoustic energy suitable to eject a droplet. Preferably the methods are executed automatically under control of programming of a controller of an acoustic ejection system.
    Type: Grant
    Filed: March 24, 2008
    Date of Patent: March 1, 2011
    Assignee: Labcyte Inc.
    Inventors: Shehrzad Ahmed Qureshi, Richard G. Stearns
  • Publication number: 20110037980
    Abstract: A zeta potential measurement system comprising: a cell having a cell wall and bottom for holding suspended particles; an optical measurement probe having a probe tip comprising a transparent and conducting thin film coating which prevents ionic current from accumulating charge on the probe tip, and wherein the optical measurement probe is inserted through the cell wall such that the probe tip is in fluid communication with the sample; a counter electrode inserted through the cell wall opposite to the optical measurement probe; a laser source which is disposed so as to deliver light to the optical measurement probe via an optical directional coupler and optical waveguide; wherein the optical measurement probe focuses the light onto a front surface of the probe tip, such that the light reflected from the front surface of the optical measurement probe and light backscattered from particles in the sample are collected by the probe tip, and thereafter focused to a optical waveguide and delivered through the couple
    Type: Application
    Filed: August 11, 2009
    Publication date: February 17, 2011
    Inventors: Paul J. Freud, Michael N. Trainer
  • Publication number: 20110040504
    Abstract: In accordance with some embodiments of the present disclosure, a method for determining fruit maturity is disclosed. The method includes measuring acceleration data associated with an impulse response signal of a target fruit to an excitation force applied to such a target fruit, computing a frequency response of the impulse response signal based on digitized acceleration data, determining a first order resonance frequency from the frequency response, and non-destructively determining a level of maturity for the target fruit based on one or more physical properties of the target fruit and the first order resonance frequency.
    Type: Application
    Filed: August 11, 2009
    Publication date: February 17, 2011
    Applicant: Rong Zhi Xin Science and Technology Development (Beijing) Co., Ltd.
    Inventors: TIANTIAN LIU, LIN YANG, GANG WU, WELHONG GU
  • Publication number: 20100332165
    Abstract: Electrochemical Impedance Spectrum (EIS) data are used directly to predict the pulse performance of an energy storage device. The impedance spectrum of the EIS is obtained in-situ using pre-existing techniques. A simulation waveform is configured such that the period of the pulse is greater than or equal to the lowest frequency of the impedance measurement. If the pulse is assumed to be periodic for analysis purposes, the complex Fourier series coefficients can be obtained. The number of harmonic constituents are selected so as to appropriately resolve the response, but the maximum frequency should be less than or equal to the highest frequency of the impedance measurement. In some cases, the measured frequencies of the impedance spectrum do not match the corresponding harmonic components of the simulated pulse wave. This is resolved by estimating the impedance measurements at the desired frequencies using linear interpolation, cubic spline fits, or other comparable methods.
    Type: Application
    Filed: June 11, 2010
    Publication date: December 30, 2010
    Inventors: John L. Morrison, William H. Morrison, Jon P. Christophersen, Chester G. Motloch
  • Publication number: 20100327888
    Abstract: In a method for determining the size and shape value (M) for a solid material (S), in particular scrap metal, in an arc furnace (1), an electrode flow fed to an electrode (3a, 3b, 3c) for forming an arc furnace (L) between the electrode (3a, 3b, 3c) and the solid (S) is measured (30) and from the measured electrode flow (I (t)), an effective measurement value of the electrode flow is determined (31) and from the measured electrode flow (I (t)) (32), a flow part associated with a frequency range of the measured electrode flow is determined (32), and a quotient of the flow part and an effective measurement value is formed as a measurement of the shape and size value of the flow (M). Thus, a method is provided that enables a property of a fusible element introduced into one of the arc furnaces to be determined.
    Type: Application
    Filed: January 12, 2009
    Publication date: December 30, 2010
    Applicant: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Arno Döbbeler, Klaus Krüger, Thomas Matschullat, Detlef Rieger
  • Patent number: 7822565
    Abstract: A system and method for monitoring RF power is described. In one embodiment the system samples RF power that is generated by an RF generator to obtain RF signals that include information indicative of electrical characteristics at a plurality of particular frequencies that fall within a frequency range. The RF signals are digitized to obtain a stream of digital RF signals that include information indicative of electrical characteristics at the plurality of particular frequencies, and the information indicative of electrical characteristics is successively transformed, for each of the plurality of particular frequencies, from a time domain into a frequency domain.
    Type: Grant
    Filed: December 31, 2007
    Date of Patent: October 26, 2010
    Assignee: Advanced Energy Industries, Inc.
    Inventors: Victor Brouk, Jeff Roberg
  • Publication number: 20100250169
    Abstract: A method for evaluating data representing a plurality of excitations of a plurality of sensors; the method comprising: (a) storing the data as a plurality of entries in an information store; each respective sensor-excitation pair being a respective entry; (b) exercising a fit relationship employing at least one first sine value to determine a fit value substantially simultaneously for at least a portion of the plurality of entries; (c) ascertaining a measure of fit error between the data and the fit value for the portion of entries; (d) employing the measure of fit error to estimate at least one next sine value; (e) employing the at least one next sine value to perform a fit optimization operation with the data substantially simultaneously for the portion of entries; and (f) repeating steps (c) through (e) until a desired number of the sine values has been exercised.
    Type: Application
    Filed: March 24, 2009
    Publication date: September 30, 2010
    Applicant: Boeing Company, a corporation of the State of Delaware
    Inventors: Charles Edward Goodman, William Brian Hayes
  • Publication number: 20100250170
    Abstract: A method of wirelessly interrogating a sensing device comprising a plurality of passive sensors, to determine a measurement parameter, comprises the steps of repeatedly interrogating the sensing device using a predetermined transmission signal and detecting the response; estimating the measurement parameter for each sensor by means of an analysis of the data accumulated as a result of the interrogation step, and determining the average of the parameters derived from the estimating step for each sensor, using a weighted average, in which the weightings depend on the amplitude of the sensor response. The measurement parameter may be a resonant frequency where the passive sensors are resonant devices, and the sensors may be SAW devices.
    Type: Application
    Filed: March 22, 2010
    Publication date: September 30, 2010
    Inventors: Victor Alexandrovich Kalinin, John Peter Beckley, Bryn James Dixon
  • Publication number: 20100235113
    Abstract: A digital processor for use in a conveyor belt rip detector, which provides excitation signals at a selected frequency to inverted and noninverted sensor loops on a conveyor belt and then detects corresponding received signals from the sensor loops. The digital processor then performs FFTs on the corresponding received signals to provide respective received signal frequency spectrums. Next magnitude and phase values of the selected frequency in the respective received signal frequency spectrums are used to determine a qualitative state of the sensor loops. The selected frequency has a lowest detected ambient noise level, and the magnitude value is a normalized magnitude value.
    Type: Application
    Filed: May 27, 2010
    Publication date: September 16, 2010
    Applicant: VEYANCE TECHNOLOGIES, INC.
    Inventors: Jack Bruce Wallace, John James Gartland, Richard Herman Blausey, Edward Louis Kerekes, JR.
  • Publication number: 20100228509
    Abstract: A method of processing an input signal for performing spectrum analysis is disclosed. The input signal comprises a desired signal and an interference signal. A crosslation is performed to process an input signal to efficiently produce discrete-time crosslation function values for the input signal. A Fourier Transform is then performed to generate frequency-dependent values. The method is particularly useful when the interference is of an impulsive or transient nature.
    Type: Application
    Filed: March 2, 2010
    Publication date: September 9, 2010
    Inventor: Weislaw Jerzy SZAJNOWSKI
  • Patent number: 7783440
    Abstract: A method for obtaining a modulation transfer function (MTF) of a knife-edge target imaged by an electro-optical device is described. The method includes the steps of: (a) obtaining edge response data points, where a data point includes a perpendicular distance, d, to the knife-edge target; and (b) constructing a sequence of line slopes of the edge response data points, where a line slope includes a spread of edge response data points. The method then selects a line slope that minimizes the spread of edge response data points, and calculates the MTF, based on the edge response data points included in the selected line slope. The MTF is provided to a user. An edge response data point is defined by a pair of values of (d, E) of a pixel, where distance, d, is the shortest distance between the pixel and a line slope and the pixel has an intensity value, E.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: August 24, 2010
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventors: Cynthia Lynne Lewis, Andrew P. Sacco
  • Patent number: 7773457
    Abstract: Systems and methods are provided for acquiring seismic data using a wireless network and a number of individual data acquisition modules that are configured to collect seismic data and forward data to a central recording and control system. In one implementation, a number of remote modules (301) are arranged in lines. Base station modules (302) receive information from the lines and relay the information to a central control and recording system (303). Radio links operating on multiple frequencies (F1-F12) are used by the modules (301). For improved data transfer rate, radio links from a remote module (301) leap past the nearest remote module to the next module closer to the base station.
    Type: Grant
    Filed: October 4, 2006
    Date of Patent: August 10, 2010
    Assignee: Wireless Seismic
    Inventors: Douglas Crice, Mihai Beffa
  • Patent number: 7765075
    Abstract: A method for spectral analysis of a signal (s1(t)) in several frequency bands with different frequency resolution adapts the two spectra of the signal (s1(t)) from adjacent frequency bands relative to one another in the transitional range of the two frequency bands. The associated device contains a unit for discrete convolution (3), which implements a smoothing of the discrete power spectra (|S1(k)|2) of the discrete signal (s1(k)) from adjacent frequency bands in the transitional range of the two frequency bands.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: July 27, 2010
    Assignee: Rohde & Schwarz GmbH & Co. KG
    Inventors: Gregor Feldhaus, Hagen Eckert
  • Publication number: 20100148071
    Abstract: An inspection apparatus for inspecting a subject (sample) (for example, performing identification or imaging of the subject) using an expansion coefficient with a relatively small amount of data. The inspection apparatus includes a transforming unit that performs a wavelet transform on a terahertz time waveform obtained using a terahertz wave detected by a detecting unit. In addition, the inspection apparatus includes a selecting unit that selects, from a first expansion coefficient in the wavelet transform, a second expansion coefficient stored in advance and included in the first expansion coefficient. Furthermore, the inspection apparatus includes a comparing unit for comparing a first value of the second expansion coefficient with a second value of the second expansion coefficient selected by the selecting unit.
    Type: Application
    Filed: November 25, 2009
    Publication date: June 17, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Michinori Shioda
  • Patent number: 7738598
    Abstract: An instantaneous frequency measurement (IFM) receiver includes a receiver module for determining a frequency fe of a received signal. Also included is a discrete Fourier transform (DFT) module configured to sum values of digital samples of data in a block of data, wherein the values of the digital samples of data are based on the frequency fe. A confirmation module confirms the frequency fe, if the sum has a value greater than a predetermined threshold. The DFT module is configured to obtain the sum of N-sample points of data which are disposed in the block of data by using a DFT kernel function.
    Type: Grant
    Filed: September 15, 2006
    Date of Patent: June 15, 2010
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventors: Stuart M. Lopata, James B. Y. Tsui, Maan J. Broadstock, Charles R. Ward
  • Patent number: 7733940
    Abstract: The present invention provides for a method of receiving a signal spread over a frequency range, and in particular a direct sequence spread spectrum signals including the step of employing a Fast Fourier Transform (FFT) in the Doppler search. In particular, the invention relates to the receipt of spread spectrum signals such as those transmitted as part of a GPS system.
    Type: Grant
    Filed: December 13, 2002
    Date of Patent: June 8, 2010
    Assignee: NXP B.V.
    Inventors: Saul R. Dooley, Amites Sarkar, Andrew T. Yule
  • Patent number: 7725277
    Abstract: In a method for performing a frequency analysis of an AC voltage signal, in particular in a power mains, an upper limit of the period length of a fundamental oscillation in the AC voltage signal is determined. A sequence of sampling values of the AC voltage signal is obtained over a duration longer than the upper limit of the period length, thereby ensuring that more than a period of the fundamental oscillation is sampled. Selected from the sequence of sampling values is a subset of sampling values, with the subset sampling substantially one period of the fundamental oscillation. At least a portion of the sampling values not included in the subset is altered, and a frequency is calculated based on the obtained sequence of sampling values, the subset of sampling values and the altered portion of the sampling values.
    Type: Grant
    Filed: January 8, 2008
    Date of Patent: May 25, 2010
    Assignee: Siemens Aktiengesellschaft
    Inventor: Robert Bösnecker
  • Patent number: 7720646
    Abstract: A signal processor and a tracking method of a signal search range are provided which can read out precisely a specific spectrum having frequency varied. A signal processor includes an FFT computation portion to compute spectrum data by fast-Fourier-transforming an input signal, a spectrum selection portion to select a specific spectrum, a spectrum search portion to search sequentially the specific spectrum selected by the spectrum selection portion from the spectrum data computed by the FFT computation portion, and a search range computation portion to compute the search range of the spectrum searched by the spectrum search portion based on the frequency of the specific spectrum, in which the search range computation portion computes the search range based on the varied frequency of the specific spectrum and makes it track the varied specific spectrum, when the frequency of the specific spectrum varies.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: May 18, 2010
    Assignee: Ono Sokki Co., Ltd.
    Inventor: Tomio Miyano
  • Patent number: 7715996
    Abstract: The present invention is a novel method of performing spectral analysis on a digital signal. The received signal is segmented into a number of data blocks, which may be disjoint or overlapping. For each data block, the signal is differentiated, and the Gram-Schmidt process is used to obtain orthogonality between a signal and its derivative. The complex extension leads to computation of phase using either the inverse tangent function or the complex logarithm. Finally, frequency estimation follows through differentiation of the unwrapped phase.
    Type: Grant
    Filed: September 27, 2007
    Date of Patent: May 11, 2010
    Assignee: The United States of America as represented by the Director of the National Security Agency
    Inventor: Adolf Cusmariu
  • Patent number: 7711452
    Abstract: One embodiment of the present invention provides a system that efficiently conducts vibrational characterizations for a computer system having variable component configurations. During operation, the system receives a given component configuration associated with the computer system. Next, the system looks up the given component configuration in a resonant spectra library, which contains structural resonant frequencies for a number of possible component configurations for the computer system. If the given component configuration is found in the resonant spectra library, the system retrieves a set of structural resonant frequencies associated with the given component configuration. The system subsequently controls one or more vibration sources within the computer system to avoid the set of structural resonant frequencies.
    Type: Grant
    Filed: October 22, 2007
    Date of Patent: May 4, 2010
    Assignee: Oracle America, Inc.
    Inventors: Georgios K. Konstadinidis, Kenny C. Gross, Keith A. Whisnant
  • Publication number: 20100106442
    Abstract: One or more embodiments of the present invention relates to an iterative method for generating an almost-constant, nearly constant, or substantially-constant envelope time signal with prescribed Fourier transform magnitude in the frequency domain, and a constant envelope time signal whose Fourier transform magnitude closely matches the prescribed Fourier transform magnitude in the frequency domain. Different starting points for the iterative algorithm give rise to different solutions and their accuracy can be adjusted using a monotonic error criterion presented here.
    Type: Application
    Filed: October 28, 2008
    Publication date: April 29, 2010
    Inventors: UNNIKRISHNA SREEDHARAN PILLAI, KE YONG LI
  • Publication number: 20100097200
    Abstract: A method and device for identifying and classifying objects, electromagnetic radiation being emitted by a sensor, the radiation components reflected on objects being received by the sensor, the received signals being analyzed by comparison with stored characteristic values and the class of the reflecting object being deduced on the basis of the analysis. To this end, an analyzer is provided for analyzing the received signals, a memory is provided for storing characteristic patterns, its stored patterns being compared with the analyzed signals and thus the class of the reflecting objects being deducible on the basis of the comparison.
    Type: Application
    Filed: April 26, 2006
    Publication date: April 22, 2010
    Inventors: Joerg Hilsebecher, Martin Randler, Paco Haffmans, Ruediger Jordan
  • Publication number: 20100088048
    Abstract: A method to predict a state of a power system and a device to perform the method are presented, where the method includes the step of performing a Fast Fourier Transform on samples of a periodic waveform signal in order to determine a frequency spectrum of the signal, where the signal was derived from at least one measurable electric quantity of the power system and is representative for the state of the power system. Frequencies and related complex amplitudes at selected peaks in the frequency spectrum are determined and stored together with a time stamp. Afterwards, a predicted value of the periodic waveform signal in the time domain is determined at a prediction time by calculating a sum of sinusoidal signals at the prediction time, where each of the sinusoidal signals is characterized by one of the determined frequencies and its related complex amplitude as well as the time stamp.
    Type: Application
    Filed: December 8, 2009
    Publication date: April 8, 2010
    Inventors: Bertil Berggren, Tord Bengtsson, Stefan Roxenborg
  • Publication number: 20100070227
    Abstract: Illustrative embodiments provide systems, applications, apparatuses, computer software program products, and methods related to identification of electrical appliances by electrical characteristics.
    Type: Application
    Filed: October 30, 2008
    Publication date: March 18, 2010
    Inventors: Roderick A. Hyde, Jordin T. Kare, Lowell L. Wood, JR.
  • Patent number: 7676337
    Abstract: An irreversible-reaction measurement method comprising: a step in which a perturbation is applied to one of the divided portions of a measurement sample placed in a light path of a Fourier-transform spectrophotometer to cause an irreversible-reaction while a mirror of the spectrophotometer remains at a data point; a step in which interferogram is detected from the sample portion placed in the path at predetermined time intervals after the application of the perturbation; a step in which the mirror moves to and remains at the next data point after the reaction of the sample portion reaches an end point; a step in which the sample portion placed in the light path is changed to the next sample portion each time the mirror moves to the next data point; and a step in which the irreversible-reaction of the measurement sample is analyzed in accordance with the interferogram obtained by repeating the steps.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: March 9, 2010
    Assignee: JASCO Corporation
    Inventors: Kenichi Akao, Seiichi Kashiwabara, Toshiyuki Nagoshi
  • Patent number: 7676336
    Abstract: According to an inventive scheme for introducing a watermark into an information signal, the information signal is at first transferred from a time representation to a spectral/modulation spectral representation). The information signal is then manipulated in the spectral/modulation spectral representation in dependence on the watermark to be introduced to obtain a modified spectral/modulation spectral representation, and subsequently an information signal provided with a watermark is formed based on the modified spectral/modulation spectral representation. An advantage is that, due to the fact that the watermark is embedded and/or derived in the spectral/modulation spectral representation or range, traditional correlation attacks as are used in watermark methods based on a spread-band modulation cannot succeed easily.
    Type: Grant
    Filed: October 30, 2006
    Date of Patent: March 9, 2010
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung E.V.
    Inventors: Juergen Herre, Ralph Kulessa, Sascha Disch, Karsten Linzmeier, Christian Neubauer, Frank Siebenhaar
  • Patent number: 7664339
    Abstract: Provided is a method for digital image representation based upon Discrete Projective Fourier Transform (DPFT) constructed in the noncompact (DNPFT) and compact (DCPFT) realizations of geometric Fourier analysis on SL(2,C) groups. Novel characteristics are that the model is well adapted to perspective image transformations and well adapted to the retinotopic (conformal) mapping of the biological visual system. To compute the DPFT of a digital image by Fast Fourier transform (FFT), an image is re-sampled with a non-uniform log-polar sampling geometry. A “deconformalization” procedure corrects the “conformal lens optics” of the conformal camera to render image perspective transformations.
    Type: Grant
    Filed: May 3, 2005
    Date of Patent: February 16, 2010
    Inventor: Jacek Turski
  • Patent number: 7643952
    Abstract: A method processes an optical image. The method includes providing a measured magnitude of the Fourier transform of a two-dimensional complex transmission function. The method further includes providing an estimated phase term of the Fourier transform of the two-dimensional complex transmission function. The method further includes multiplying the measured magnitude and the estimated phase term to generate an estimated Fourier transform of the two-dimensional complex transmission function. The method further includes calculating an inverse Fourier transform of the estimated Fourier transform, wherein the inverse Fourier transform is a spatial function. The method further includes calculating an estimated two-dimensional complex transmission function by applying at least one constraint to the inverse Fourier transform.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: January 5, 2010
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Aydogan Ozcan, Michel J. F. Digonnet, Gordon S. Kino
  • Patent number: 7640139
    Abstract: Provided are an envelope processor 103, for obtaining an envelope for a detected signal; a FFT unit 104, for converting the envelope into a frequency spectrum; a peak detector 105, for smoothing the frequency spectrum by calculating a moving average, for further performing smoothing and differentiation for the spectrum, and detecting, as peaks, frequency points at which a sign of a differential coefficient is changed from positive to negative, for extracting peaks having a predetermined threshold value or greater, and for sorting the extracted peaks and detecting upper peaks; and a diagnosis processor T, for diagnosing an abnormality based on the detected peaks.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: December 29, 2009
    Assignee: NSK Ltd.
    Inventors: Juntaro Sahara, Yasushi Mutoh, Takanori Miyasaka, Masanobu Yamazoe
  • Patent number: 7640123
    Abstract: Aspects of a method and system for detecting Bluetooth signals utilizing a wideband receiver are provided. In this regard, a frequency band may be scanned by receiving signals on each of a plurality of sub-bands for an amount of time, the energy received in each band may be compared to a threshold, and whether each sub-band comprises a Bluetooth transmission may be determined based on a FFT. Additionally, the FFT may enable determining on which Bluetooth channel a detected transmission occurred. A FFT may be performed when energy detected in a sub-band is higher than a threshold. The sub-bands may each be a WLAN channel. A type of a detected Bluetooth transmission may be determined based on a number of scans in which the transmission is detected. Each sub-band may be received for less than or equal to 68 ?s divided by the number of sub-bands.
    Type: Grant
    Filed: October 30, 2007
    Date of Patent: December 29, 2009
    Assignee: Broadcom Corporation
    Inventors: Brima Ibrahim, Steven Deane Hall
  • Patent number: 7638999
    Abstract: Relay devices, systems and methods for obtaining an accurate representation of a current monitored with a Rogowski coil, without integration of the Rogowski coil output voltage signal in the time domain.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: December 29, 2009
    Assignee: Cooper Technologies Company
    Inventors: Ljubomir A. Kojovic, Stephen E. Williams
  • Publication number: 20090312971
    Abstract: An apparatus for locating inferior parts in distribution line equipment may include a wireless noise receiver for continually receiving multiple noise-free frequencies and converting the received multiple noise-free frequencies into an audio frequency signal, a signal processor for quantifying a power frequency and harmonic frequencies of the audio frequency signal, a signal analyzer for calculating variation of the power frequency and the harmonic frequencies, determining the number of changed frequencies based on the calculated variation, detecting a radio frequency noise signal generated from an inferior part based on the calculated variation and the number of changed frequencies, and a frequency calibrator for determining a noise-free band, selecting the multiple noise-free frequencies from the noise-free band, and managing a list of the selected multiple noise-free frequencies.
    Type: Application
    Filed: June 12, 2009
    Publication date: December 17, 2009
    Inventor: Hyun-Chang Lee
  • Publication number: 20090306920
    Abstract: Embodiments of a system that determines a condition associated with an integrated circuit disposed on a circuit board are described. During operation, the system receives electromagnetic-interference (EMI) signals from one or more antennas while the integrated circuit is operating, where the one or more antennas are disposed on the circuit board. Then, the system analyzes the received EMI signals to determine the condition.
    Type: Application
    Filed: June 4, 2008
    Publication date: December 10, 2009
    Applicant: SUN MICROSYSTEMS, INC.
    Inventors: Steven F. Zwinger, Kenny C. Gross, Aleksey M. Urmanov