225 results about "Relative amplitude" patented technology

A method for determining a degree of acoustic non-linearity of an earth formation from seismic signals transmitted into the formation from within one wellbore and received from the formation in another wellbore. The seismic signals include two selected discrete frequencies. The method includes spectrally analyzing the received signals, determining from the spectral analysis the presence of a frequency representing a sum of the two selected frequencies, and determining a relative amplitude of the sum frequency with respect to the amplitudes of the two selected discrete frequencies. In a particular embodiment, the method includes determining the presence of a frequency in the spectrally analyzed signals representing the difference between the selected discrete frequencies, and determining the presence of harmonic multiples of one of the two selected discrete frequencies.

Metrology targets are formed by a lithographic process, each target comprising a bottom grating and a top grating. Overlay performance of the lithographic process can be measured by illuminating each target with radiation and observing asymmetry in diffracted radiation. Parameters of metrology recipe and target design are selected so as to maximize accuracy of measurement of overlay, rather than reproducibility. The method includes calculating at least one of a relative amplitude and a relative phase between (i) a first radiation component representing radiation diffracted by the top grating and (ii) a second radiation component representing radiation diffracted by the bottom grating after traveling through the top grating and intervening layers. The top grating design may be modified to bring the relative amplitude close to unity. The wavelength of illuminating radiation in the metrology recipe can be adjusted to bring the relative phase close to π / 2 or 3π / 2.

A distributed fiber optic sensor simultaneously interrogates the sensing fiber with two counter propagating light beams. One beam is set to a constant frequency. The second beam is modified to contain a “comb” of frequencies, with each frequency component in the comb offset by a predetermined amount. Each of the frequency components in the comb, herein referred to as teeth, is able to interact with the counter-propagating beam through the Brillouin scattering process. With proper selection of the comb characteristics such as the number of teeth, the frequency spacing of teeth, the spectral width of teeth, and the relative amplitude of the teeth, a representation of the Brillouin spectrum at each point in the fiber can be obtained simultaneously with a single pass through the fiber.

Near field signal properties are used to determine a location by utilizing two magnetic antennas arranged so that the null axes are perpendicular and lie in a plane of interest, such as the horizontal plane. The two antennas may be used as transmitting antennas or receiving antennas. The antennas may be driven so as to produce an equivalent of an omnidirectional pattern in the plane of interest by driving the antennas in an orthogonal manner. The orthogonal drive may be time orthogonal or phase orthogonal. A location is determined based on near field response which may include propagation properties, which may include amplitude, phase, relative amplitude, or phase, or other properties. In one embodiment, multiple transmitters are utilized to determine the location of a single receiver. In another embodiment, multiple receivers are utilized to determine the location of a single transmitter. A space efficient magnetic antenna is disclosed.

Detector signals in a pulse oximeter are analyzed to determine a quality of the signals in relation to desired information content or artifact content. The analysis involves performing a transform on a signal to obtain frequency related information and analyzing the frequency related information to obtain a value independent of a shape and waveform of a spectrum of the time-based signal. In one implementation, the analysis involves the relative amplitude or power measures of corresponding peaks in the red and infrared spectra. For example, the ratio of the amplitude of the fundamental peak in the red spectrum and the amplitude of the fundamental peak in the infrared spectrum may be tracked over time. In another implementation, the analysis involves consideration of the relative phase of the fundamental and harmonic components of a signal. In either case, signals including desired physiological information can be distinguished from artifact affected signals. Based on this analysis, signals can be validated or an appropriate processing algorithm can be selected.

The present invention provides a method and apparatus for arriving at true relative amplitude destretched seismic traces from stretched seismic traces. The method compensates for offset varying reflection interference effects due to normal moveout. Stretch factors β and also input spectra are determined for NMOR stretched seismic traces. Estimates are then made of stretched wavelet spectra from the input spectra. A destretched wavelet spectra is then obtained. Shaping correction factors are determined by taking the ratio of the destretched wavelet spectra to the stretched wavelet spectra and are applied to the input spectra of the stretched traces to arrive at a destretched trace spectra. True relative amplitude scaling factors are computed by taking the ratio of a true relative amplitude property of the destretched wavelet spectra to a corresponding true relative amplitude property of the stretched wavelet spectra. Finally, the true relative amplitude scaling factors are applied to the destretched trace spectra to arrive at true relative amplitude destretched seismic traces.

A plurality of control points are defined having a known spatial relationship relative to an array of transducers. An amplitude is assigned to each control point. A matrix is produced containing elements which represent, for each of the control points, the effect that producing a modeled acoustic field having the assigned amplitude with a particular phase at the control point has on the consequential amplitude and phase of the modeled acoustic field at the other control points. Eigenvectors of the matrix are determined, each eigenvector representing a set of phases and relative amplitudes of the modeled acoustic field at the control points. One of the sets is selected and the transducer array is operated to cause one or more of the transducers to output an acoustic wave each having an initial amplitude and phase such that the phases and amplitudes of the resultant acoustic field at the control points correspond to the phases and relative amplitudes of the selected set.

A system for a neurostimulator coupled to electrodes. The system comprises an input device configured for generating control signals. The system further comprising memory storing a first set of variable values defining a first spatial relationship between a central ideal pole of a first polarity and the plurality of electrodes, a second set of variable values defining a second spatial relationship respectively between four ideal poles of a second polarity and the first ideal pole, and a third set of variable values defining relative intensities between the four ideal poles. The system further comprises control circuitry configured for modifying the first variable values, the second variable values, and / or the third variable values, and generating stimulation parameter values defining relative amplitude values for the electrodes that emulate the ideal poles, and instructing the neurostimulator to convey electrical energy to the electrodes in accordance with the stimulation parameter values.

A system comprises a processing chamber for maintaining a hydrogen plasma at low pressure. The processing chamber has a long, wide, thin geometry to favor deposition of thin-film silicon on sheet substrates over the chamber walls. The sheet substrates are moved through between ends. A pair of opposing radio frequency electrodes above and below the workpieces are electrically driven hard to generate a flat, pancaked plasma cloud in the middle spaces of the processing chamber. A collinear series of gas injector jets pointed slightly up on a silane-jet manifold introduce 100% silane gas at high velocity from the side in order to roll the plasma cloud in a coaxial vortex. A second such silane-jet manifold is placed on the opposite side and pointed slightly down to further help roll the plasma and maintain a narrow band of silane concentration. A silane-concentration monitor observes the relative amplitudes of the spectral signatures of the silane and the hydrogen constituents in the roll-vortex plasma and outputs a process control feedback signal that is used to keep the silane in hydrogen concentration at about 6-7%.

A modular cellular wireless communication base station includes a plurality of active radiator modules located at a desired antenna location. Each module includes at least one antenna, a transmitter, and a receiver. A beam forming network controls relative amplitudes and phases of each of the modules. An RF front end transmits over a low power link with the active radiator modules via the beam forming network and receives over the low power link via a low noise amplifier. A delay diversity module provides a transmission CDMA delay diversity.

An antenna system (10) capable of transmitting electromagnetic radiation using the technique of combining two quadrature signals for either right hand circular polarization or left hand circular polarization using a circularly polarized antenna (30), or alternately, either horizontal or vertical polarization using a linearly polarized antenna (36) while incorporating feedback for automatically correcting for amplitude and phase variations in the quadrature paths using a switch (12) which selects the sense of the polarization and electronic optimization of the transmit antenna (30, 36). The antenna system includes a control circuit having a polarization switch (12) for receiving a transmission signal. The switch (12) generates first and second output signals which are substantially similar to the transmission signal, and determines whether to apply the transmission signal to one of a first or a second switch output. A coupler (14) receives the first and second switch outputs and generates first and second output signals having a predetermined phase difference. A variable detector (16, 18) detects and adjusts a relative amplitude and phase of the respective first and second output signals. An error correction circuit (34) determines an adjustment to the variable phase detector to vary the phase and amplitude of the first and second output signals in accordance with the relative amplitude and phase of the respective first and second output signals.

A system and method are provided for estimating blood oxygen saturation independent of optical sensor encapsulation due to placement in blood, where the blood includes a blood flow characteristic of: a relatively low, a stasis, a stagnant value. The method includes determining tissue overgrowth correction factor that includes optical properties of the tissue that cause scattering of the emitted light to a detector and relative amplitudes of the emitted light wavelengths. A corrected time interval measured for infrared light is based on an infrared signal and a corrected time interval for red light is determined by subtracting red light signal due to presence of tissue overgrowth. The red light signal due to tissue overgrowth is proportional to total infrared signal less nominal infrared signal. Oxygen saturation is estimated based on standard calibration factors and the ratio of the corrected infrared time interval and the corrected red time interval.

The invention provides a near-field calibration method for relative amplitude and phase characteristics of spherical surface array antenna channels, and aims to provide a method with few calibration source and capable of automatically performing self-correction on the relative amplitude and phase characteristics. The near-field calibration method is characterized in that: calibration frames distributed around a spherical surface antenna array plane are set up on the periphery of a phased-array antenna and a calibration frame is set up at the center of the phased-array antenna, thus a conformalspherical surface array distribution model for antenna unit approximate uniform distribution is formed; optical equipment is used for performing high-precision measurement on a coordinate position ofeach calibration antenna relative to a central point of the spherical surface array antenna, and a spatial distance and an axial included angle between each array element on the spherical surface array antenna and each calibration antenna are calculated; and a calibration reference signal generated by calibration test equipment is used for calibrating uplink / downlink channels of the spherical surface array antenna, and amplitude / phase characteristics of element antenna channels are obtained through deducting relative amplitude and phase characteristics of the antenna and amplitude / phase changes introduced by the spatial distances and axial deflection between each calibration antenna and each array element.

The present invention provides a method and apparatus for arriving at true relative amplitude destretched seismic traces from stretched seismic traces. The method compensates for offset varying reflection interference effects due to normal moveout. Stretch factors β and also input spectra are determined for NMOR stretched seismic traces. Estimates are then made of stretched wavelet spectra from the input spectra. A destretched wavelet spectra is then obtained. Shaping correction factors are determined by taking the ratio of the destretched wavelet spectra to the stretched wavelet spectra and are applied to the input spectra of the stretched traces to arrive at a destretched trace spectra. True relative amplitude scaling factors are computed by taking the ratio of a true relative amplitude property of the destretched wavelet spectra to a corresponding true relative amplitude property of the stretched wavelet spectra. Finally, the true relative amplitude scaling factors are applied to the destretched trace spectra to arrive at true relative amplitude destretched seismic traces.

The present invention provides a sensor system and a corresponding sensing method employing the sensor system. The sensor system comprises a sensor (12) having an input (20) and an output (22), a feedback path (16) from the output to the input, and a filter (14; 92) in the feedback path. The filter comprises a narrow band filter, which is tuned or tunable to a respective one of signals that are wanted signals and signals that represent interference signals. The sensor and the filter are arranged so as to alter the relative amplitudes of the wanted signals and the interference signals in order to increase the relative amplitude of the wanted signals and reduce the relative amplitude of the interference signals.

A system remotely detects a gas leakage from a pipeline in an area. The system detects a gas leakage by determining an absorption or emission of gasses in the area. The gas detection system includes at least two light sources. The lasers can include lasers for detecting absorbance of gasses in the area, lasers for stimulating emission of gasses in the area, and lasers for detecting a pathlength. Absorption is determined based on the relative amplitude difference of emitted and reflected light beams. Emission is determined based on an amount emission stimulated by absorbed lasers. Pathlength is determined calculating time of flight of a light beam. The detection system calculates a concentration of the gasses in the area using the determined absorption and pathlength. The detection system can also generate an image representing a gas leakage in the area. The detection system may be attached to an unmanned aerial vehicle.

A system to detect subsurface activity. The system employs vibration sensor pairs, with each sensor pair having a shallow sensor and a deep sensor. Outputs of the sensors of a pair are processed together and events are detected based on the relative values detected by the sensors of the pair. When signal energy departs from a detected background level, the relative amplitude and frequency content of vibrations measured at the shallow and deep sensors may be compared. The comparison may be performed, at least in part, using a classifier that discriminates between subsurface activity and surface to activity. The outputs of sensor pairs may be aggregated to make a determination of whether subsurface activity exists and / or its location. Aggregation may involve comparing the outputs of the same sensor pair at multiple time intervals or may involve comparing the outputs of arrayed sensor pairs.

A shaker movement permits an arbitrary path of motion in a shaker's shaking action. The shaker movement comprises independent control over the "X" and "Y" directions of the shaking actions by a pair of track assemblies, each track assembly comprising a pair of fixed rods and a pair of sliding rods that are interconnected with each other in a rectangular, grid-like pattern. Motion in both directions can be driven by a single motor utilizing independent pulley-and-belt systems or by two synchronized motors which are connected to a sliding rod of each track assembly. By altering the relative amplitude, phase angle, and frequency between the "X" and "Y" directions, the shaking action can follow a desired path. The shaker path can be varied from the traditional circular orbital motion or linear motion, to a new group of shaking patterns in which the direction of the shaking movement can reverse. The new patterns of shaker movement cause the liquid being shaken to be more thoroughly mixed, with less power input, and at a lower angular frequency than is practical with traditional paths of motion. This results in higher rates of gas transfer to and from the liquid, resulting in greater growth of a bacterial culture, and for higher rates of mass transfer at equivalent levels of energy input.

The invention provides a seismic data reconstruction method. According to the method, after acquired, seismic data is subjected to Fourier transform; in a time-frequency domain, the seismic data is subjected to singular value decomposition and truncation treatment; in a frequency domain, the seismic data which is Hankel matrixed is subjected to singular value decomposition and truncation treatment. At the premise of causing little damage to valid signals, random noise can be suppressed, and the seismic data with missing channels can be subjected to interpolation; the difference in vibration amplitude between an interpolated signal and an original signal decreases nonstop with iteration; the use of step interpolation leads to improved coherence of the seismic data. Denoising and interpolation are performed through singular value decomposition in the time-frequency domain, the defect that simultaneous denoising and interpolation is unavailable in the conventional method is overcome, loss of the valid signals during denoising can be effectively reduced, and relative amplitude preservation is available.

A distributed fiber optic sensor simultaneously interrogates the sensing fiber with two counter propagating light beams. One beam is set to a constant frequency. The second beam is modified to contain a “comb” of frequencies, with each frequency component in the comb offset by a predetermined amount. Each of the frequency components in the comb, herein referred to as teeth, is able to interact with the counter-propagating beam through the Brillouin scattering process. With proper selection of the comb characteristics such as the number of teeth, the frequency spacing of teeth, the spectral width of teeth, and the relative amplitude of the teeth, a representation of the Brillouin spectrum at each point in the fiber can be obtained simultaneously with a single pass through the fiber.

This invention discloses a method for testing phase difference and relative amplitude of input signals in single channels, which generates modulation signals by a control frequency splitter then to modulate the input signals to merge them to mono-channel transmission, then the merged signals are transformed, sampled, window- added and FFT to get information of phase difference, amplitude and relative amplitude.

A device and a method to be used by laryngeally impaired people to improve the naturalness of their speech. An artificial sound creating mechanism which forms a simulated glottal pulse in the vocal tract is utilized. An artificial glottal pulse is compared with the natural spectrum and an inverse filter is generated to provide an output signal which would better reproduce natural sound. A digital signal processor introduces a variation of pitch based on an algorithm developed for this purpose; i.e. creating prosody. The algorithm uses primarily the relative amplitude of the speech signal and the rise and fall rates of the amplitude as a basis for setting the frequency of the speech. The invention also clarifies speech of laryngectomees by sensing the presence of consonants in the speech and appropriately amplifying them with respect to the vowel sounds.

PCT No. PCT / AU96 / 00717 Sec. 371 Date Apr. 9, 1998 Sec. 102(e) Date Apr. 9, 1998 PCT Filed Nov. 14, 1996 PCT Pub. No. WO97 / 18466 PCT Pub. Date May 22, 1997A mining machine (4) has a vertically movable jib (6) mounted in front of it and carrying a drum shaped drilling head (12) at its forward end. The drilling head is provided with radially projecting picks which rip coal out of a coal seam (1) located between an underburden (3) and an overburden (2). A forwardly-facing directional microphone (16) is mounted on the forward end of the machine (4) between the lines M where it can monitor the resonant frequencies of the picks. Electrical circuitry mounted on the machine controls the position of the jib (6) in accordance with the relative amplitudes of a unique set of natural resonant frequencies produced by the picks during mining.

Systems and methods for applying vibration to and tracking the position and motion of the human body. A vibration system includes a vibrator capable of converting an electrical signal into vibration, and a motion tracking device capable of tracking the motion and position of a user. In one aspect, the vibrator is arranged on or about the human body on a pectoralis major muscle and spaced away from a sternum. In another aspect, the vibrator is arranged on or about the human body such that a first pattern of vibrations are generated on the body's surface. The first pattern of vibrations matches in relative amplitude a second pattern of vibrations generated on the body's surface when the body generates sound.

The invention discloses a method for determining amplitude phase errors of direction-finding channels space-borne array antenna. The method comprises the steps of configuring a calibrating signal source, a calibrating feed source and a calibrating processor on a basic structure of each of the direction-finding channels of the array antenna according to the characteristics of number change and error segmentation of the direction-finding channels of the array antenna; sequentially changing conduction relationships among switch matrixes by means of the characteristic of the conduction relationships among the switch matrixes; obtaining responses of N paths of channels to calibrating signals under the different conduction relationships among the switch matrixes; grouping a plurality of responses in different states into an equation set; obtaining a relative amplitude and a relative phase of the N paths of channels by solving the equation set; and therefore, obtaining an amplitude phase error of each of the direction-finding channels of the array antenna. The method provided by the invention is convenient in operation and capable of precisely determining the amplitude phase errors of the direction-finding channels of the array antenna.

A first measured value is determined which is associated with the proximity of a target to an inductive sensor. A first voltage signal having a first amplitude is generated. The first voltage signal is provided as a driving signal to the inductive sensor. A sensor current signal is received as a return signal output from the inductive sensor. The sensor current signal has an amplitude proportional to a proximity of the target to the inductive sensor. The sensor current signal is converted to a corresponding second voltage signal having a second amplitude. A differential measuring technique is used to determine the first measured value in accordance with relative amplitudes of said first voltage signal and said second voltage signal.

A method and system for calibrating transmit and receive antenna patterns for time division duplex (TDD) is described. A station in a communications network comprises at least two antennas configured to operate together for both transmitting and receiving modes. A phase setting difference between the transmit and receive antenna patterns may be determined and used to determine a relative amplitude setting for the transmit antenna pattern and / or a relative amplitude setting for the receive antenna pattern.

The invention discloses a stable underwater communication node awakening signal detection method. The stable underwater communication node awakening signal detection method comprises the following steps of: S1, emitting a dual-frequency or multi-frequency awakening signal; S2, according to a set initial frequency, transform point number and frequency resolution ratio, executing CZT (chirp z transform) on a unit circle on the awakening signal; S3, searching an extreme value of a zoom spectrum of CZT, judging a signal as the awakening signal if an estimated relative frequency interval and relative amplitude relationship between frequency components are kept unchanged, or judging the signal is not the awakening signal; and S4, after the signal is determined as the awakening signal, powering on an integral communication node to enable the node to be transferred into a working state, and when the node completes working, cutting off a power supply to enable the node to be transferred into a sleeping state. According to the stable underwater communication node awakening signal detection method disclosed by the invention, due to the high frequency resolution ratio, multiple groups of frequencies can be adopted for combination to awaken a plurality of nodes of an underwater sensor network without worrying about mutual interference, so that detection false-alarm is greatly reduced and a service life of the underwater wireless sensor network is prolonged.