Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Hiro

98 results about "Frequency profile" patented technology

Method and apparatus for transmitting a signal using simultaneous FM and AM modulation

InactiveUS20060029397A1Wider flat top regionElectromagnetic transmittersFall timeCarrier signal
There is provided method for transmitting binary data contained in respective successive time cells, the data being in the form of an optical signal obtained by amplitude modulation and frequency modulation of an optical carrier wave, with a 0 bit data value having a 0 bit mean amplitude having a 0 bit amplitude time duration and a 0 bit frequency having a 0 bit frequency duration, and a 1 bit data value having a 1 bit mean amplitude having a 1 bit amplitude time duration and a 1 bit frequency having a 1 bit frequency duration; the improvement wherein: independently adjusting the 0 bit mean amplitude relative to the 1 bit mean amplitude; independently adjusting the 0 bit frequency relative to the 1 bit frequency; and independently adjusting time duration of the frequency profile of the 1 bit relative to the time duration of the amplitude profile of the 1 bit, whereby to extend the error-free propagation of the optical signal though a dispersive optical fiber beyond the dispersion limit. There is provided a method for transmitting Non-Return-To-Zero (NRZ) binary data contained in respective successive time cells, the data being in the form of an optical signal obtained by amplitude modulation and frequency modulation of an optical carrier wave, with a 0 bit data value having a 0 bit mean amplitude having a 0 bit amplitude time duration and a 0 bit frequency having a 0 bit frequency duration, and a 1 bit data value having a 1 bit mean amplitude having a 1 bit amplitude time duration and a 1 bit frequency having a 1 bit frequency duration; the improvement wherein: the phase across each 1 bit data value is substantially constant, and the phase of the carrier changes across each and every 0 bit by an amount equal to the product of the frequency difference between the 1 bit and the 0 bit and the duration of the 0 bit; whereby to extend the error-free propagation of the optical signal though a dispersive optical fiber beyond the dispersion limit. In accordance with one form of the present invention, there is provided a method for transmitting binary data contained in respective successive time cells, the data being in the form of an optical signal obtained by amplitude modulation and frequency modulation of an optical carrier wave, with a 0 bit data value having a 0 bit mean amplitude having a 0 bit amplitude time duration and a 0 bit frequency having a 0 bit frequency duration, and a 1 bit data value having a 1 bit mean amplitude having a 1 bit amplitude time duration and a 1 bit frequency having a 1 bit frequency duration; the improvement wherein: the amplitude profile of the 1 bit is substantially bell-shaped, and the frequency profile of the 1 bit is substantially square-shaped, with steeper rise and fall time and a wider flat top region; whereby to extend the error-free propagation of the optical signal though a dispersive optical fiber beyond the dispersion limit.
Owner:AZNA +1

Optical frequency sweep control and readout by using a phase lock

The invention allows for the accurate, real-time readout of the optical frequency of a swept-wavelength laser device by counting the number of fringes of a calibrated etalon that occur as the laser is swept. The distinguishing feature of the present invention is that the etalon fringe signal is phase-locked to a slave signal of a higher multiple frequency. The higher frequency of the slave signal divides the frequency interval of the etalon fringe spacing by the additional frequency multiple. The slave signal therefore generates a scale for optical frequency that is of higher resolution than possible with the etalon alone. The phase-lock also insures that the slave signal tracks monotonic scans of the optical frequency regardless of scan profile.
The invention also allows for the precise, real-time control of the optical frequency of a laser during the sweep of the laser. By comparing a signal proportional to the transmission of light through a calibrated Fabry-Perot etalon to a reference control signal, the phase difference between etalon transmission signal and the reference signal may be fed back to the laser to drive the phase difference to zero (phase-lock). The phase-lock ensures that the optical frequency profile of the sweep follows exactly the frequency profile of the reference signal. Tailoring the input reference signal controls the velocity of the optical-frequency sweep.
Owner:PRECISION PHOTONICS CORP

System, method, and computer program product for simulating epicardial electrophysiology procedures

An aspect of various systems and methods provides, but not limited thereto, novel means for simulating physiological systems and processes in vitro in order to test surgical devices and train practitioners in the use of surgical devices. An aspect of various embodiments further provides in vitro anatomical components, such as a thorax, lungs, heart and pericardium, configured to contain at least one fluid having a pressure-frequency profile that may mimic typical pressure-frequency waveforms of in vivo anatomical fluids. A model communication system may be used to communicate the desired pressure-frequency profiles to the in vitro anatomical fluids. In a further aspect of various embodiments, an access device, e.g. a surgical instrument, configured to sense pressure, frequency, and/or a pressure-frequency profile may be inserted into one or more anatomical components of the in vitro model in order to test the instrument and/or train a practitioner in proper use of the instrument. An access device communication system may be used to communicate data to the practitioner. This data may include, for example, pressure-frequency data and/or the location of a portion of the access device with respect to the various in vitro anatomical components.
Owner:UNIV OF VIRGINIA ALUMNI PATENTS FOUND

Direct digital synthesis pixel clock generator

A Direct Digital Synthesis pixel clock generator for use in electrophotographic printers. A controller receives a start-of-scan signal and a facet 0 signal. In response, the controller sends a pre-stored frequency control word to a Direct Digital Synthesis Oscillator. The Direct Digital Synthesis Oscillator sends pulses at a frequency that depends on the frequency control word to a Digital Phase Shift Circuit. The controller also applies a sequence of delay profile words to the Digital Phase Shift Circuit. Each delay profile word causes the Digital Phase Shift Circuit to delay a contemporaneous pulse from the Direct Digital Synthesis Oscillator between 0° and 360° degrees, with the actual delay depending upon the delay profile word. The delay profile words are selected such that scan line pixels are "adjusted" in position. A phase-locked-loop circuit integrates and smoothes the frequency step changes. The output of the phase-locked loop circuit is applied to a synchronizer that synchronizes the pixel clocks with the start-of-scan. Alternatively, the controller applies a sequence of frequency profile words to a Direct Digital Synthesis Oscillator. The Direct Digital Synthesis Oscillator then generates pulses at a rate that depends upon the applied frequency profile word. The frequency profile words are selected such that the pixels are "adjusted" in position. A phase-locked-loop circuit then integrates and smoothes the output of the Direct Digital Synthesis Oscillator. The resulting pulse frequency is applied to a synchronizing circuit that synchronizes the pixel clocks with the start-of scan-signals.
Owner:XEROX CORP

Earthquake stratum thickness variation analysis method

InactiveCN102508295ASmooth componentAccurate portionSeismic signal processingDamping factorContinuous wavelet transform
The invention discloses an earthquake stratum thickness variation analysis method in which a high-resolution instantaneous frequency decomposed on the basis of an empirical mode is used to analyze stratum thickness variation. Firstly, an earthquake signal is subjected to an empirical mode decomposing process to obtain a multilevel intrinsic mode function; then, the instantaneous frequency of the intrinsic mode function is calculated; and according to the variation of the instantaneous frequency, the stratum thickness variation is analyzed. According to the earthquake stratum thickness variation analysis method, a triple B spline is adopted as an interpolating function in the empirical mode decomposing process; the instantaneous frequency is calculated by using an instantaneous frequency calculation method with a damping factor on the basis of continuous wavelet transform; the obtained intrinsic mode function and instantaneous frequency profile have good lateral continuity and few false appearances, accord with the reality and also have good noise immunity. The earthquake stratum thickness variation analysis method is favorable for improvement of the reliability and the effectiveness of the earthquake stratum thickness variation analysis, is suitable for processing and explaining practical earthquake data, provides a powerful basis for predicting a reservoir stratum, and improves the precision of oil-gas field exploration and development.
Owner:XI AN JIAOTONG UNIV

System, method, and computer program product for simulating epicardial electrophysiology procedures

An aspect of various systems and methods provides, but not limited thereto, novel means for simulating physiological systems and processes in vitro in order to test surgical devices and train practitioners in the use of surgical devices. An aspect of various embodiments further provides in vitro anatomical components, such as a thorax, lungs, heart and pericardium, configured to contain at least one fluid having a pressure-frequency profile that may mimic typical pressure-frequency waveforms of in vivo anatomical fluids. A model communication system may be used to communicate the desired pressure-frequency profiles to the in vitro anatomical fluids. In a further aspect of various embodiments, an access device, e.g. a surgical instrument, configured to sense pressure, frequency, and / or a pressure-frequency profile may be inserted into one or more anatomical components of the in vitro model in order to test the instrument and / or train a practitioner in proper use of the instrument. An access device communication system may be used to communicate data to the practitioner. This data may include, for example, pressure-frequency data and / or the location of a portion of the access device with respect to the various in vitro anatomical components.
Owner:UNIV OF VIRGINIA ALUMNI PATENTS FOUND
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products