355 results about "Effective frequency" patented technology

A method for producing low-noise laser output at wavelengths ranging from IR through visible to UV in various operation modes from a monolithic microchip laser comprises schemes of (1) generating one or two fundamental beam(s) from light source(s) selected upon the desired wavelength(s), polarization(s), and other features related to the desired laser output; (2) intracavity beam combination / separation due to the walk-off effect in one or more birefringent crystal(s) transparent to the propagating lights and highly anisotropic; (3) wavelength conversion in one or more nonlinear optical crystal(s); (4) compact and efficient pump source(s); and (5) minimization of intracavity loss / noise. One resonator cavity supports only one fundamental beam, which eliminates the green problem. The gain media can be selected from an extensive group of materials including isotropic and naturally birefringent crystals, with polarization dependent or independent laser emissions. Laser devices constructed in accordance with the inventive method are demonstrated with various configurations.

A seismic coherence algorithm based on wavelet transformation comprises the following steps: 1) preprocessing the seismic data; 2) executing fine frequency spectrum analysis to the processed seismic data for confirming the effective frequency spectrum range of seismic data; 3) executing horizon interpretation to the seismic data and executing processions of interpolation, smoothing, etc.; 4) using seismic data and the interpreted seismic horizon as input, executing wavelet transformation to a certain seismic channel for inputting earthquake data with a high resolution derivative wavelet function for obtaining the wavelet transformation frequency division result; 5) computing the instantaneous amplitude or / and instantaneous frequency or / and instantaneous phase of instantaneous wavelet field; 6) computing the instantaneous coherence using a coherence algorithm based on wavelet instantaneous phase or a coherence algorithm based on wavelet transformation; 7) reconstructing the instantaneous coherence for obtaining high-frequency or low-frequency coherent data volume; 8) repeating the steps 4-7 to each seismic channel for obtaining the coherence computing result of all seismic channels; and 9) drafting with the computed instantaneous coherent data.

A network analyzer is capable of measuring the antenna return loss in a live cellular network. The network analyzer receives and analyzes the base station transmitted signal to determine which transmit frequencies are active. Based on information relating to the correlation between the transmit frequency and the associated receive frequency, the network analyzer determines the active receive frequencies. An unmodulated source that avoids inclusion of the active receive frequencies is generated by the network analyzer. To fill in the antenna sweep with the previously avoided frequencies, the network analyzer generates another source containing only those avoided frequencies when no calls are active on the avoided frequencies. Alternatively, the antenna return loss on the avoided frequencies is interpolated from the measured frequencies. As a further alternative, the network analyzer receiver determines a nearby frequency to an active frequency, and adaptively measures the nearby frequency as the avoided (active) frequency.

A method of processing a workpiece in the chamber of a plasma reactor includes introducing a process gas into the chamber, simultaneously (a) capacitively coupling VHF plasma source power into a process region of the chamber that overlies the wafer, and (b) inductively coupling RF plasma source power into the process region, and controlling plasma ion density by controlling the effective frequency of the VHF source power. In a preferred embodiment, the step of coupling VHF source power is performed by coupling VHF source power from different generators having different VHF frequencies, and the step of controlling the effective frequency is performed by controlling the ratio of power coupled by the different generators.

Soil water content and bulk electrical conductivity may be determined by time domain reflectometry at multiple depths in the soil such that the entire soil profile from the surface to a user-selected depth may be characterized. A short rise-time pulse is passed into an electrode and the reflected pulse is captured at multiple times. A waveform of reflection coefficient versus time is determined, which may be used to determine the pulse travel time, effective frequency and reflection coefficients at times necessary for the determination of the soil water content and bulk electrical conductivity.

The invention relates to a link adapting method based on an AMC-ARQ (Adaptive Modulation and Coding-Automatic Repeat-reQuest) striding layer. The link adapting method comprises the step of designing a mapping relation of a receiving SNR (Signal to Noise Ratio) of a physical layer and MCS (Modulation Coding Scheme) by utilizing a QoS (Quality of Service) demand of a data link layer and the information of the physical layer according to a target packet error rate of the physical layer. According to an ergodic method, the optimal packet error rate of the physical layer, the maximum retransmission times of the ARQ of the data link layer and the size combination of a rearranging timer of the data link layer are searched, so that the use ratio of effective frequency spectrum is maximal. According to the link adapting method provided by the invention, the physical layer and the data link layer are comprehensively considered; the correlation influence of the parameters between the two layers is fully utilized to obtain AMC and ARQ parameters; the optimal parameter combination for maximizing the efficiency of the effective frequency spectrum is obtained; and the time delay is calculated by dividing the time delay into two parts of a queuing time delay and a transmission time delay, so that the calculation for the time delay is more accurate. According to the link adapting method provided by the invention, the selection for a modulation coding mode is relative to a channel condition and transmission times, and the redundant information transmitted at each time is fully utilized.

A system and method for dithering a clock signal during idle times is disclosed. An integrated circuit (IC) includes a number of functional units and a clock tree. The clock tree includes a root level clock-gating circuit, a number of regional clock-gating circuits, and a number of leaf level clock-gating circuits. The root level clock-gating circuit is coupled to distribute an operating clock signal to the regional clock-gating circuits, while the regional clock-gating circuits are each configured to distribute the operating clock signal to correspondingly coupled ones of the leaf level clock-gating circuits. The IC may further include a control unit configured to monitor activity levels and indications from each of the functional units. The control unit may cause the root clock-gating circuit to dither the clock signal if the IC is idle, wherein dithering includes reducing the duty cycle and the effective frequency of the operating clock signal.

A method for producing low-noise laser output at wavelengths ranging from IR through visible to UV in various operation modes from a monolithic microchip laser comprises schemes of (1) generating one or two fundamental beam(s) from light source(s) selected upon the desired wavelength(s), polarization(s), and other features related to the desired laser output; (2) intracavity beam combination / separation due to the walk-off effect in one or more birefringent crystal(s) transparent to the propagating lights and highly anisotropic; (3) wavelength conversion in one or more nonlinear optical crystal(s); (4) compact and efficient pump source(s); and (5) minimization of intracavity loss / noise. One resonator cavity supports only one fundamental beam, which eliminates the green problem. The gain media can be selected from an extensive group of materials including isotropic and naturally birefringent crystals, with polarization dependent or independent laser emissions. Laser devices constructed in accordance with the inventive method are demonstrated with various configurations.

The invention relates to a method for realizing mixed network structure, belonging to the wireless communication technique, especially the frequency spectrum application of cognitive radio system and the realization of physical transmission medium of cognitive radio mixed network structure, wherein it comprises: based on the interfere temperature model, calculating the allowed maximum receiving power of receiver at said time, calculating the real emission power of sending terminal, calculating the combination of two effective frequency spectrums, and realizing the point-to-multipoint (PMP) and mesh topology in mixed structure. The inventive classified spectrum share method can realize the mixed structure that supporting the point-to-multipoint (PMP) and mesh topology, to increase the system capacity and expand the area cover range.

A method and system for modifying the pulse width modulation frequency for controlling the backlit illumination intensity of a liquid crystal display (14). The modified pulse width modulation frequency may be selected to reduce distortion in the display (14) while allowing for a wide range of dimming settings for the display (14). A pulse width modulation signal (95) may be also be phase shifted such that a string of light sources (110-115) may be sequentially activated to generate a effective frequency greater than that of the frequency of the pulse width modulation signal (95).

A voltage controlled oscillator 1, a variable frequency divider 2, a phase comparator 3, and a loop filter 4 form a Phase Locked Loop (PLL). A sigma-delta modulator 5 sigma-delta modulates data obtained by adding a fractional part M2 of the frequency division factor data with modulation data X by using an output signal of the variable frequency divider 2 as a clock. An output signal of the sigma-delta modulator 5 is added to an integral part M1 of the frequency division factor data, and the resultant data becomes effective frequency division factor data 13 of the variable frequency divider 2. An output signal of the sigma-delta modulator 5 also becomes control data 14 after passing through a D / A converter 6, a low-pass filter 7, and an amplitude adjustment circuit 8. The control data 14 is inputted into a frequency modulation terminal of the voltage controlled oscillator 1. Therefore, it is possible to provide a frequency modulator that can use a reference signal source having no frequency modulation function, and perform modulation over a wide range of frequencies based on a digital modulation signal.

The invention discloses a colorful blood flow imaging based on an ultrasonic Doppler frequency spectrum and a display method thereof. The display method comprises the following steps: (1) selecting a sampling door which is large enough; (2) dividing the sampling door into M sub-doors; (3) calculating the frequency spectrum of a time series summed in every sub-door; (4) calculating the upper and lower envelope curves of the frequency spectrum corresponding to every sub-door, determining an effective frequency band analysis area, and calculating the average blood flow speed and a mean square error in the effective frequency band analysis area; and (5) converting speed and variance yields into colorful codes and displaying by using a preset color mapping table. According to the display method provided by the invention, a plurality of doors are utilized to obtain the flow velocity and variance distribution at different positions along the cross section of a blood vessel, therefore, the distribution of the blood flow in a spatial position can be observed better, the volume and blood flow velocity can be measured more precisely, and the colorful blood flow imaging has an important clinical meaning on the diagnosis of cardiovascular diseases.

An integrated device is disclosed which has a substrate and a Rare-Earth Doped Semiconductor layer (REDS layer) integrated with the substrate. The REDS layer is patterned to define one or more optically amplifying structures each having a first I / O port for receiving or outputting a first optical signal, and at least one pump energy receiving port for receiving pumping energy in the form of at least one of electrical pump energy and / or optical pump energy. In one particular set of embodiments, at least one of the optical amplifying structures is a Raman type amplifier where a corresponding pump energy receiving port is structured for receiving Raman type pumping energy having an effective frequency which is about one optical phonon frequency higher than a signal frequency of an optical signal supplied at a corresponding I / O port. Methods are disclosed for fabricating Rare-Earth Doped Semiconductor layers, including providing such layers in semiconductor-on-insulator (SOI) structures and for enhancing the effective, long-term concentrations of incorporated, rare earth atoms. Additionally, non-parallel pumping techniques are disclosed.

The invention provides a method for measuring thickness of coatings through the ultrasonic signal spectrum filter technology in a nondestructive mode, and belongs to the technical field of ultrasonic non-destructive testing. The method includes the steps that normalization processing is conducted on reflective sound pressure P[reflection] (x1) by ultrasonic incident sound pressure P[incidence] (x0), and then normalization sound pressure reflection coefficients R (x1-x0) of the coatings are acquired, and the R (x1-x0) is expanded to plural Fourier series through the spectrum analysis technology and divided into an independent real part function Real (f) and an independent imaginary part Imag (f); Fourier transformation is conducted on a real part function V[real] (f) in an effective frequency band acquired through windowing processing to acquire a power spectrum M (tau) of the real part function V real (f), FFT filtering bandwidths are selected according to the occurrence positions of maximum values of the power spectrum, the V[real] (f) is sequentially filtered to acquire a series of cosine functions, the periods of the cosine functions are read, propagation sound time ti of ultrasonic waves in the coatings is calculated, and then the thickness of the coatings is represented by the cooperation of longitudinal wave sound velocity of the coatings. The method is not affected by material attributes and the process environment, the problems that in a conventional ultrasonic method, aliasing occurs in time domains, and resonant frequency of the spectrum is difficult to recognize are solved, and the problem of ultrasonic thickness measurement of the multiple coatings is solved.

The invention discloses an EEG (electroencephalogram) feature extraction method. The EEG feature extraction method includes the steps of removing artifacts in background EEG data and EEG data to be processed to obtain effective frequencies of the background EEG data and the EEG data to be processed, and respectively dividing the effective frequencies of the background EEG data and the EEG data to be processed into a plurality of data segments; extracting time-frequency feature and morphological feature of each data segment to obtain time-frequency feature value and morphological feature value of each data segment; calculating to obtain a frequency distribution function of the feature values according to the time-frequency feature value and the morphological feature value of each data segment of the background EEG data; obtaining probabilities of occurrence of the time-frequency feature value and the morphological feature value of each data segment of the EEG data to be processed according to the frequency distribution functions of the background EEG data; and calculating to obtain IMF-VoE (intrinsic mode functions and upper and lower envelopes) feature values according to the probabilities of the feature values. Change features of EEG signals can be quickly and effectively recognized by the IMF-VoE feature values to monitor brain statuses.

The invention relates to an intelligent method for testing cardiograms by basing on quanta a simple recursion neural network, which comprises the steps that: the cardiac electric signals are sent to a self-adaptation power frequency disturbance-restriction module for restricting the disturbance of the power frequency; the two output cardiac electric signals in the previous step are sent to a blind baseline drift disturbance-restriction module so as to remove the breath baseline drift disturbance; the output cardiac electric signals in the second step are sent to the quanta simple recursion neural network for carrying out cardiac electric intellectual test and output. The self-adaptation power frequency disturbance-restriction module comprises two same groups of self-adaptation power frequency disturbance-restriction units, and carries out power frequency disturbance-restriction on the two collected groups of cardiac electric signals simultaneously and respectively. The self-adaptation power frequency disturbance-restriction module can automatically restrict power frequency disturbance by adopting the cardiac electric power frequency disturbance-restriction method basing on QR decomposing recursive least squares (RLS) algorithm self-adaptation trap technology. The invention can not only realize cardiac electric intellectualization test, but also remove the power frequency and the breath baseline drift disturbance in the effective frequency band of cardiac electric signals, and solve the difficulty that digital filtration method eliminates the disturbance of aliasing in spectrum.

The invention discloses a fault diagnosis method of a motor bearing based on a time-frequency domain statistical characteristic. The fault diagnosis method comprises the following steps that: speed pulse signals and vibration signals of the motor bearing in T time interval are collected simultaneously, and a frequency conversion curve f is calculated according to the speed pulse signals; the vibration signals at a stationary speed are intercepted according to the frequency conversion curve and are sectioned; health indicators of the vibration signals in all segments are calculated according toa formula of the health indicators, a fault degree grade of each segment is obtained by comparing the health indicators with a fault threshold table, and the fault grade with the highest fault degreegrades counted is the fault grade of the motor bearing; Hilbert envelope spectrums of the vibration signals in all segments are calculated, effective frequencies of all envelope spectrums are determined according to a calculation method of the effective frequencies, the most frequent occurrence frequency of the effective frequencies counted is a fault frequency, and then a fault position of the bearing is determined. The overall fault degree and the fault position of the motor bearing are accurately obtained by counting the fault grade of the vibration signals and the effective frequencies ofthe envelope spectrums in a plurality of time intervals.

A master-slave system includes a clock and phase signal generator to produce a clock signal at a given frequency and a phase signal at an effective frequency, where the phase signal may or may not be periodic and has an effective frequency less than the given frequency. A clock line is connected to the clock and phase signal generator to carry the clock signal. A phase line is connected to the clock and phase signal generator to carry the phase signal. The phase line includes a phase-to-master path to carry a phase-to-master phase signal and a phase-from-master path to carry a phase-from-master phase signal. A master device is connected to the clock line and the phase line. A data bus is connected to the master device. A slave device is connected to the data bus, the clock line and the phase line. The slave device processes data on the data bus in response to the clock signal and the phase signal.

A method for optimizing a wavelet packet structure for subsequent tree-structured coding which preserves coherent spatial relationships between parent coefficients and their respective four offspring at each step. A valid frequency tree is defined by a wavelet packet decomposition algorithm. Constraints are placed on the pruning of the frequency tree in order to select valid frequency trees as each step. These constraints include considering any four offspring sub-bands as candidates for pruning only when their current frequency decomposition level is the same as that of their respective spatially co-located parent sub-band, and pruning the spatially co-located offspring sub-bands when pruning only the parents results in an invalid wavelet packet structure.

The invention relates to an off-resonance type wheel-type generator based on a cantilever beam piezoelectric vibrator, and belongs to the field of piezoelectric power generating. A rotary disc slide sink cavity is communicated with a central hole on the other side and communicated with an annular cavity through a guide hole; a cantilever shaft sleeved in the center hole is connected with a side plate installed on a side of the sink cavity; the side plate is provided with an annular cavity and a guide hole; extrusion balls are filled in the guide holes of the rotary disc and the side plate; a cantilever of a metal substrate pressed by the end cap in the annular cavities of the rotary disc and the side plate and a bonded piezoelectric wafer constitute a piezoelectric vibrator; an excitation disc is filled in a slide formed the slide sink cavity and the cantilever shaft; balls are embedded in the inner rim and the outer rim of the excitation disc; and a lift inclined plane, a convex surface, return inclined surface and a concave surface on the two sides of the excitation disc form an excitation unit. The advantages and characteristics of the off-resonance type wheel-type generator are that no fixed support is needed and no electromagnetic interference exists; the piezoelectric oscillator structure is reasonable; off-resonance power generation is realized and the deformation of the radius is determined by a limit surface; stress points are the same and only bear compressive stress, so that the electric power generation is large; the reliability is high; an effective frequency band width is large; and the off-resonance type wheel-type generator is especially suitable for a low rotating speed environment.

The invention relates to a method for avoiding mutual interference in a radar system. The method comprises the steps of acquiring an intermediate frequency signal of an ith radar in the radar system, wherein the maximum effective frequency of the intermediate frequency signal of the radar is gi<max>; performing interference analysis on the intermediate frequency signal; calculating a new working frequency starting point f'i which can not be interfered; changing the working frequency starting point of the ith radar into f'i so as to avoid the interference with other radars. The method disclosed by the invention can be used for ensuring that a plurality of radars in the radar system do not need to stagger the time of transmitting signals; meanwhile, radio frequency signal frequency spectrums of the plurality of radars can be mutually overlapped, so that each radar does not need to use an independent frequency band, thus greatly improving the frequency spectrum utilization efficiency, and ensuring that more radars working simultaneously can be supported on a certain frequency spectrum.

The invention relates to a vibrator, in particular to an electric-acoustic transformation acoustic generator with the function of vibration. A magnetic fluid is arranged at the bottom of a bowl-shaped magnetizer. A protruding elastic damping balance is arranged in the corresponding position of the magnetic fluid on a bottom cover. The elastic damping balance and a vibration unit with magnetic fluid are propped against each other in the vibration state, so as to overcome the disadvantage of small damp in a miniature electric-acoustic generator in the related technology, enable the resonance amplitude to be inhibited when the miniature electric-acoustic generator works, increase the voltage to be borne by the miniature electric-acoustic generator and widen the effective frequency band of the miniature electric-acoustic generator. Therefore, the resonance amplitude is inhibited, so that the collision of the inner parts of the acoustic generator can be avoided, and the power to be borne by the invention is increased. Besides, the counterforce is strengthened when the resonance happens, so that the effective frequency band of the electric-acoustic transformation acoustic generator gets wider.

The aim of the invention is to improve a method for the primary control so that reserve power that is practically completely available for the effective frequency boost within seconds is available also in the stem turbine part of a gas / steam turbine installation. To this end, the pressure stage is operated with a control valve (6, 7, 8) that is throttled to such an extent that a frequency boost power reserve is built up. Said power reserve is used for frequency boosting in the event of an underfrequency by correcting the desired value depending on the underfrequency. Said corrected value corresponds to an effective area of the flow that is increased vis-â-vis the throttled condition of the control valve (6, 7, 8) and acts on the effective area of flow of the control value (6, 7, 8) with an impressed signal that approaches zero after a predetermined time. Said signal is chosen in such a manner that, despite the correction of the desired value, a stable operative condition is maintained in accordance with the response behavior of the gas / steam turbine installation to the increased effective area of flow.

The embodiment of the invention provides a network searching method, device and terminal. The network searching method comprises the following steps: acquiring wireless spectrum information of the environment located by a mobile terminal, and extracting an effective frequency point from the wireless spectrum information; detecting whether the effective frequency point is the target frequency pointof the network searching of the terminal; if the effective frequency point is the target frequency point of the network searching of the terminal, performing network searching according to the targetfrequency point and a network system corresponding to the target frequency point. Before interacting information with a base station, the effective frequency point in the environment is firstly searched, and the target frequency point therein is determined, and finally, the network searching is performed according to the target frequency point and the network system corresponding to the target frequency point, the ineffective interaction time between the mobile terminal and the base station can be greatly reduced, thereby shortening the network searching duration and improving the network searching efficiency.

The invention discloses a coherent value obtaining method and system of an earthquake data amplitude spectrum. The method comprises: step 1, obtaining a three-dimensional post-stack earthquake data body; step 2, calculating an effective frequency range for obtaining an amplitude spectrum; step 3, selecting a certain sampling point in the three-dimensional post-stack earthquake data body, and setting a slave data body which centers on a certain sampling point and includes a J-channel earthquake record; step 4,superposeing a window function on the J-channel earthquake record in the slave data body, and respectively performing Fourier transformation to obtain the amplitude spectrum of the J-channel earthquake record; step 5, obtaining and using the amplitude spectrum of the effective frequency range in the amplitude spectrum of the J-channel earthquake record to construct a J-dimensional covariance matrix, and calculating the characteristic roots of the J-dimensional covariance matrix, wherein the ratio of the maximum characteristic root in the characteristic roots to the sum of all the characteristic roots is a coherent value of a certain sampling point; and step 6, repeating step 3 to step 5, traversing each sampling point in the three-dimensional post-stack earthquake data body, and obtaining and recording the coherent value of each sampling point.

The invention discloses a locomotive motor bearing automatic diagnostic method based on a vibration acceleration signal, comprising the steps of: acquiring a vibration acceleration signal and a speed key phase signal of a motor bearing; performing order tracking and constant-angle incremental sampling, and converting the vibration acceleration signal into an angular-domain vibration acceleration signal; calculating an FFT spectrum and an EEVS enhanced envelope spectrum; setting effective frequency bands in the FFT spectrum and the EEVS enhanced envelope spectrum according to a bearing fault frequency; calculating the fault probability of each component of the bearing according to the band energy in the FFT spectrum and the EEVS enhanced envelope spectrum; setting weights and calculating the weighted probability of each component of the bearing; comparing a preset fault reference probability with the weighted probability of the current bearing so as to automatically determine a fault type and representing the severity of the fault by the weighted probability.

A clock recovery scheme for a digital communication receiver has a fixed fractional delay line that is driven by a fixed frequency reference clock source, to provide a plurality of respectively offset phase delayed versions of the reference clock. A phase lock loop, to which the received signal is coupled, controllably steps through the phase delayed versions of the reference clock, so as to controllably increase or decrease the effective frequency of the reference clock and thereby produce a recovered clock signal.

The invention relates to a seismic phase and frequency correction method based on complex seismic trace decomposition and reconstruction. The method includes the following steps that first, according to an effective frequency band range recorded in known earthquakes, a subwave base traversing the effective frequency band range and a non-stationary convolution model are established; second, the subwave base is converted into complex numbers through Hilbert conversion, and a complex subwave base is established; third, the non-stationary convolution model is changed into the complex number form through the complex subwave base, complex reflection coefficients (please see the formula in the specification) are resolved through linear operation and sparse inversion constrained by L1 norm, the complex reflection coefficients (please see the formula in the specification) are substituted into the non-stationary convolution model in the complex number form, the real number part of the complex reflection coefficients is obtained, reconstruction on the seismic section is achieved, and according to the frequency of the seismic subwaves in the complex subwave base changed before reconstruction and obtained phase information in the complex reflection coefficients, frequency correction, phase correction and synchronous correction of frequency and phases on the original earthquake records are achieved. The method can be widely applied in the oil exploration process.

Provided in the invention is an audio signal processing device that comprises a first device and a second device. The first device includes a first loudspeaker outputting a first audio signal. The second device includes a first microphone and a first filter; the first microphone receives the first audio signal and carries out sampling on the first audio signal to generate first audio data; and the first filter filters frequency points of the first audio data to obtain second audio data. According to the invention, the audio signal is used to carry out data transmission, thereby solving a problem that an audio device with an audio interface can not carry out data transmission by the existing way. During the transmission process, the amplitude of the audio signal is attenuated with increasing of the distance and the frequency of the audio signal is not changed with the distance changing. Therefore, corresponding frequency points of the audio data generated by the microphone are filtered and noises are filtered, thereby obtaining frame head and frame tail information of effective information; and a signal frequency of an effective frequency point is responded according to the information so as to obtain effective information, thereby ensuring accuracy of signal transmission.

The invention uses tubes for the reduction of radiated duct noise. The tubes may be used to attenuate narrow band noise by diverting a portion of the acoustic energy through the tubes back into the duct. Upon reintroducing the diverted flow out of phase with the primary flow, acoustic cancellation is achieved. The frequency at which this occurs is dependent on the difference in the path lengths through the tubes and the separation distance—the distance separating the inlet and outlet of the tube. This invention can be used over varying frequency ranges by using an arrangement of flexible, constant length tubes. The effective frequency range is tailored by varying the separation distance and also allows the varying the angular arrangement of the tubes for more effective attenuation of spinning modes having varying propagation angle.