178 results about "Distortion factor" patented technology

The present invention relates to a photovoltaic three phase synchronization control method realizing maximum power tracking swiftly and stably, which belongs to the technical field photovoltaic power generating control. The method includes the steps as follows: judging the DeltaP / DeltaV value according to the power difference DeltaP between the current time k and the previous time and the voltage difference DeltaV; working out the Iref(k) when the photovoltaic array produces the maximum power; using the Iref(k) to adjust the uq* under the coordinates in vectorial synchronous rotation with the electric network voltage; acquiring six ways of space vectorial SVPWM impulse series according to the rotation angle degree Theta of the three phase electric network voltage, with the aim to control the inverter in order to ensure that the output current of the photovoltaic inverter has the same phase position as that of the mains voltage while ensuring the photovoltaic array is realizing the maximum power output tracking. The power factor is 1. The present invention also can adjust the Idref(k) according to local load requirements, therefore achieving adjustment to the power factor, with low synchronization current harmonic wave distortion factor.

The invention discloses a quick mode selection method and a device of an H264 video coding. The method comprises the selection of a mode in frames and the selection of the mode between the frames, wherein, for the selection of the mode in the frames, a prediction method with different fineness is chosen according to the dramatic degree of the image information changes in the prior macro block, thereby decreasing the number of the model to be chosen and confirming the final selection mode through the method of code rate-distortion factor optimizing; for the selection of the mode between the frames, the sum of the absolute difference of the corresponding pixel point of the corresponding macro block of the prior frame and the reference frame is used as a dividing basis to divide the macro block into different fineness and to correspondingly choose a prediction method with different fineness for decreasing the number of the model to be chosen and confirming the final selection mode through the method of code rate-distortion factor optimizing. The invention can decrease the number of the model to be chosen and solve the application limited problems caused by over-complicated code, over-loaded operation and over time consumption in the prior art.

An optical disc device of the present invention obtains a reproduction quality that is independent of a mark distortion by receiving a signal that is obtained from an A / D converter for digitizing a reproduction signal of an optical disc medium and an offset correction means for performing offset correction, accurately measuring a mark distortion factor in a mark pattern having a long recording width by means of a mark distortion factor measuring means, and selecting one of output signals from a PRML signal processing means and a level judge binarization means by means of a digital data demodulation selection means by utilizing the measured mark distortion factor as a judgement criterion, to be used as a demodulation binary signal.

The invention discloses a double-tube Buck-Boost type PFC (Power Factor Correction) converter based on one-cycle control, a bridge rectification circuit is then connected with a BOCBB type double-tube Buck-Boost converter; one path of output signal of a PI (proportion integral) adjuster is sent to a noninverting input end of a comparator, the other path of output signal is superposed with a sampling signal of input current and then is sent to a resettable integrator, an output end of the resettable integrator is connected with an inverting input end of the comparator, an output end of the comparator is connected with an RS (remote sensing) trigger, one end of the RS trigger is connected with a reset switch of the resettable integrator, and a Q-end output signal of the RS trigger simultaneously drives two switching tubes of the BOCBB type double-tube Buck-Boost converter after passing by a driving circuit. The converter disclosed by the invention not only can realize output voltage raising and reducing control, but also can improve a network side power factor, reduces the distortion factor of network entry current, has the advantages of simple structure, high system efficiency and the like and is convenient to control.

The invention relates to a self-adapting down-sampling stereo video compressed coding method based on a residual error macro block, adopting a stereo video coding scheme based on united compensated prediction by time and spatial correlation analysis of the video information of the left viewpoint and the right viewpoint of a stereo video and correlation analysis between the left viewpoint and the right viewpoint, wherein two images of stereo video of a stereo video image pair are formed according to the human eye vision inhibition theory; a high-resolution image can inhibit fuzzy parts in a low-resolution image, and the finally obtained stereo perception mainly depends on the high-resolution image. Based on the theory, the invention provides a down-sampling method based on a residual errormacro block, comprising the following steps: respectively adopting three down-sampling modes according to movement conditions of the image in different directions to reduce the sampling distortion factor; then according to a motion compensated prediction mode, a parallax compensated prediction mode and a united compensated prediction mode in stereo video coding, judging the severity rate of the movement of the current coding block, thereby realizing the self-adapting down-sampling method based on the residual error macro block and improving the coding efficiency.

A calibration method based on fixed and variable parameters in three-dimensional scanning system relates to the camera model parameter calibration in the visual system including the following steps: (1) fixed parameters calibration is primarily to acquire coordinates of sampling points on circular contour and heart in image coordinates through image processing techniques, and then use n sampling points to get aspect ratio through least squares method, (2) after obtaining the fixed parameters, it uses the image coordinates of image midpoint and the corresponding space coordinates of world midpoint to demarcate the initial value of variable parameters for the camera, including the equivalent focal length, main point coordinates, axis tilt factor, distortion factor and external parameters, (3) after demarcation, it takes fixed parameters as a constraint for nonlinear optimization objective function to establish a binding target function and get the optimal solution of variable parameters through the nonlinear optimization method.

The embodiment of the invention relates to a coding and decoding method, a coder, a decoder and a coder / decoder system. The coding method comprises: obtaining a predicted value according to an original image or a reconstructed image; performing transform domain processing to the predicted value; performing quantization and inverse quantization to the predicted value after transform domain processing; obtaining a residual error according to the predicted value after inverse quantization and the original image transform domain parameter; obtaining coding data according to the residual error; performing quantization to the residual error; performing inverse quantization to the quantized residual error; obtaining a reconstruction value according to the predicted value and the residual error which both finish inverse quantization processing; and obtaining a reconstruction image after performing inverse transform domain processing to the reconstruction value. The embodiment of the inventionreduces distortion factor, improves R-D performance, improves coding and decoding efficiency and lowers coding and decoding complexity.

In the prior art in which permanent magnets are regularly arranged over the whole circumference of a rotor core, a satisfactory magnetic flux distribution is hard to obtain, and the cogging torque and the distortion factor of the induced electromotive force waveform are large, whereby characteristics of a rotating electric machine are poor. Also, because the permanent magnets are arranged over the whole circumference, a large number of permanent magnets are required and cost reduction is difficult. A permanent magnet rotating electric-machine of the invention comprises a stator provided with a plurality of windings, and a rotor in which magnets are disposed in slots formed in a rotor core along an outer circumference thereof, the rotor core being fixed on a rotary shaft rotating inside the stator, and in which one magnetic pole is constituted by each group of three or more of the magnets. A total angle occupied by the group of magnets constituting one magnetic pole is in the range of 150 to 165 degrees in terms of an electrical angle.

A method of calibrating a compass sensor in consideration of a magnetic environment is provided. The method includes (a) acquiring magnetic force data by rotating a compass sensor 360 degrees, the compass sensor including a biaxial magnetometer, (b) fitting the acquired magnetic force data to an ellipse function, (c) transforming the acquired magnetic force data and the ellipse function into a circle which is centered on an origin, and (d) calculating a distortion factor based on an inclination of a major axis of the ellipse function or the acquired magnetic force data to a horizontal axis, the distortion factor indicating the degree to which a magnetic field is distorted.

The present invention relates to a predistortion signal amplifier arrangement comprising digital predistortion means for predistortion of an input signal, a non-linear power amplifier, a predistortion control arrangement comprising error estimation means for estimating the error produced in the predistorted signal and a predistortion look-up table arrangement, the content in which is updated by the estimation means. The predistortion look-up table arrangement comprises at least two look-up tables, which are updated by said estimation means and said at least two look-up tables have different number of table entries. It further comprises a combiner for combining updated values obtained from said at least two look-up tables into a composite value and said composite value comprises a distortion coefficient which is input to said digital predistortion arrangement for signal predistortion.

The invention discloses a comprehensive control method for a high-power efficient energy consuming high-frequency switching power supply. The high-power efficient energy consuming high-frequency switching power supply comprises a three-phase current inverter and a high-frequency DC / DC (Direct Current to Direct Current) converter, wherein the high-frequency DC / DC converter consists of a single-phase full-bridge inverter, a high-frequency coupling transformer and a low-voltage rectifier which are connected in series in sequence; the input end of the three-phase current inverter is connected with a group of three-phase capacitors connected in a Y form, and is connected with a power grid through a three-phase inductor L; and the three-phase current inverter is connected with the single-phase full-bridge inverter of the high-frequency DC / DC converter. According to the method, quick response of a system is realized, change of a load is tracked quickly, efficient power consumption of the system is realized, and the voltage and current distortion factors of the system are decreased.

A method of calibrating a compass sensor in consideration of a magnetic environment is provided. The method includes (a) acquiring magnetic force data by rotating a compass sensor 360 degrees, the compass sensor including a biaxial magnetometer, (b) fitting the acquired magnetic force data to an ellipse function, (c) transforming the acquired magnetic force data and the ellipse function into a circle which is centered on an origin, and (d) calculating a distortion factor based on an inclination of a major axis of the ellipse function or the acquired magnetic force data to a horizontal axis, the distortion factor indicating the degree to which a magnetic field is distorted.

The invention discloses a no-filter D-class audio amplifier based on the chaos frequency spreading modulating technology, mainly comprising a chaos frequency spreading triangle-wave generator, a comparator and a full-bridge output-stage circuit, wherein the chaos frequency spreading triangle-wave generator is used for generating chaos frequency spreading triangle-wave signals. When an audio signal is sent, the comparator is used for comparing voltage values of the audio signal and the chaos frequency spreading triangle-wave signal to output a square wave signal with changeable dutyfactor. After the power of the square signal is amplified by the full-bridge output-stage circuit, the square signal is outputted to a loudspeaker and recovered to the audio signal above the loudspeaker. The invention has the following advantages that the electromagnetic interference of the output signal of the D-class amplifier is effectively inhibited under the condition of no filter, the integration is easy, the chip area is saved, and the linearity of the chaos frequency spreading triangle wave used as the PWM carrier wave is not influenced by the modulation signal (chaos sequence) is guaranteed, thus, the distortion factor of the output audio signal is not influenced.

The present invention discloses a compressing method of the data recorded by the electric power waveform. The compressing process includes the steps of: the collected data is performed by the integer small wave conversion based on the rising format and then all the data having been converted is coded in the Huffman method; the decompressing process includes the steps of: each pressing data that is read in bit is decoded in Huffman method, and then the data having been decoded is performed by the integer small wave contra-conversion. The present invention has the characteristics of a small amount of computing, a high compressing rate, a small distortion factor, a small occupied computer resources, etc. and the method can be realized in a flushbonding system. The compressibility and the distortion factor can be adjusted according to the demand and the flexibility of the using of the software is added. The present invention can also provide a threshold value to the detail information to realize the lossless compressing and the lossy compression. The electric power system waveform recording device in the present can realize a long-time and continuous recording waveform by combining the electric hardware technology under the situation of high sampling rate and big capability and the waveform can be transmitted far away through the communication interface reliably and quickly.

The invention belongs to the technical field of image processing, and provides a processing method and device based on a projected image. The method comprises the steps that a secondary imaged image of the projected image on a projection surface is obtained, wherein the projected image is formed by projecting a preset reference image on the projection surface, and reference identification points are preset in the reference image; secondary image identification points in the secondary imaged image are obtained; a distortion factor is obtained according to the change of the position parameters of the secondary image identification points in the secondary imaged image based on the position parameters of the reference identification points in the reference image; an image to be projected is corrected according to the distortion factor. Processed projected images are made to be reduced in distortion or even be free of distortion, and thus the environment adaptive capacity of image projecting equipment is improved.

A direct-driven electric excitation double convex pole fault-tolerant wind-driven generator belongs to the wind-driven generator. The wind-driven generator is composed of two parts of a multi-pole electric excitation double convex pole electric motor and a power device. The unit electric motor are divided into C groups (C>=3). The number of each group of unit electric motor is same. The three-phase winding of each group of unit electric motor is inverted to 120 degree step wave alternating current by the full-bridge inverter respectively after the commutation of the rectification circuit. The phase displacement between the step wave alternating current outputted by the inverters of each group of unit electric motor is 90 / C degree electrical degree. When the outputs of inverter of each group of unit electric motor have been series-connected the load is provided with alternating current, the generator can still work normally after the occurring of fault and satisfies the high-reliability request of the wind-driven generator and at the same time has the advantages of low switching frequency of the amplifier tube of the inverter, small electric voltage and current stress, small distortion factor of the power-line voltage and small cubic weight.

The invention relates to an adaptive RBF (radial basis function) neural network control technique for three-phase parallel active filters, belonging to an active power filter control technique. The invention provides an adaptive RBF neural network control method for three-phase parallel active power filters, which is used for controlling a compensation current output by a three-phase parallel active power filter through a controller, thereby eliminating harmonic waves and improving the power supply quality of a power grid. According to an adaptive control rule provided by the invention, the boundedness of weights is ensured, and the stability of the controller is proved by using a Lyapunov stability theory; and simulation results show that the control method effectively reduces the distortion factor of harmonic waves and is good in dynamic response, and when parameters change, the controller has good robustness and adaptability.

A system for, and method of, noisy automatic speech recognition employing joint compensation of additive and convolutive distortions and a digital signal processor incorporating the system or the method. In one embodiment, the system includes: (1) an additive distortion factor estimator configured to estimate an additive distortion factor, (2) an acoustic model compensator coupled to the additive distortion factor estimator and configured to use estimates of a convolutive distortion factor and the additive distortion factor to compensate acoustic models and recognize a current utterance, (3) an utterance aligner coupled to the acoustic model compensator and configured to align the current utterance using recognition output and (4) a convolutive distortion factor estimator coupled to the utterance aligner and configured to estimate an updated convolutive distortion factor based on the current utterance using differential terms but disregarding log-spectral domain variance terms.

The invention discloses in-situ detecting equipment for abrasion on the rear face of a turning tool. The in-situ detecting equipment comprises an imaging device and a pose and position adjusting device, wherein the imaging device comprises a camera, a telecentric lens and coaxial light sources, the telecentric lens is mounted on the camera, and the coaxial light sources are fixed at the tail end of the telecentric lens; the pixel of the camera is not lower than 200w, and the chip of the camera is not smaller than 1 / 1.8 inch in size; the distortion factor of the telecentric lens is not higher than 0.02 percent; the image resolution of the combination of the camera and the telecentric lens is not lower than 400 pixel / mm, and the entire length is not longer than 150 mm; and the pose and position adjusting device is used for achieving multi-degree-of-freedom precision adjustment of the imaging device. During the work, the imaging device is fixed on one side, positioned on the outer normal of the rear face of the turning tool, of a lathe lateral displacement planker through the pose and position adjusting device. The in-situ detecting equipment provided by the invention has the advantages of high measuring accuracy, convenience in measurement and the like, and is applicable to abrasion on the rear face of the turning tool.

The invention discloses a large-size LCD (liquid crystal display) screen defect detecting method based on machine vision. An LCD screen is zoned, one camera is arranged in each zone and calibrated toacquire a distortion factor matrix, and a homography matrix is obtained; a pure color picture is displayed on the LCD screen, each camera shoots an LCD screen image in each corresponding zone, distortion correction is performed with the adoption of the distortion factor matrix, all LCD screen images are transformed in the same coordinate system according to the homography matrix and spliced to obtain a complete LCD screen image, the edges of the LCD screen are detected, a regional area of the LCD screen is extracted, and defect detection is performed after background texture inhibition and image intensification are performed. Defect detection of the large-size LCD screen can be effectively realized, and better universality is realized.

The invention relates to a novel cross-diamond searching method. Firstly, a crosslet mode is adopted for pre-search to find a minimum block-matching distortion (MBD) point, the MBD is taken as a center to construct a large cross searching mode to find the MBD; secondly, the MBD of the large cross mode is taken as the center to start the diamond search that a large diamond is searched first, a small diamond mode is adopted for search if the MBD is positioned at the center, and the found MBD point is the final block-matching distortion point; and if not, the large diamond search is continued. A cross-diamond also adopts the halfway stopping technique, and the speed for searching stationary blocks and half stationary blocks is improved obviously; and the modified partial distortion criterion greatly reduces the computational complexity without influencing the distortion factor. The laboratory result shows that the novel cross-diamond searching method respectively saves 41 percent and 16 percent of searching points compared with the diamond searching method and the cross-diamond searching method under the circumstances that the signal-to-noise ratio is less reduced or even is not reduced; compared with other prevalent block-matching motion estimation methods, the novel cross-diamond searching method has higher searching speed and less distortion degree.

The invention provides an amending method and an amending system directing at an unbalanced zero intermediate frequency feedback, and the amending method and the amending system are used for solving the problems of unobvious effect of the existing amending method and inexact I / Q signal. The method comprises the following steps: sampling a zero intermediate frequency feedback signal, wherein the zero intermediate frequency feedback signal comprises an I signal and a Q signal; respectively counting direct current leakage volumes of the I signal and the Q signal, and performing the direct current amending treatment on the I signal and the Q signal according to the direct current leakage volumes; counting an amplitude ratio of the I signal and the Q signal after the direct current amendment, and performing amplitude amending treatment on the I signal and the Q signal after performing the direct current amendment according to the amplitude ratio; counting a phase position difference between the I signal and the Q signal after amending the phase position, and performing phase position amending treatment on the I signal and the Q signal after performing the amplitude amendment according to the phase position difference; and performing digital distortion factor updating treatment on the I signal and the Q signal after performing the I signal and the Q signal to obtain the I signal and the Q signal to be sent. With the adoption of the amending method and the amending system, the obtained I signal and the Q signal to be sent are more exact.

Disclosed is a distortion compensating amplifier having a distortion compensator for compensating for distortion of an amplifier by updating distortion compensation coefficients so as to null a difference between a transmit signal and a feedback signal, and subjecting the transmit signal to distortion compensation processing using the distortion compensation coefficients, an amplifier for amplifying the transmit signal, which has undergone distortion compensation, in order to transmit the signal from an antenna, and a feedback unit for inputting an output signal from the amplifier to a distortion compensation coefficient updater in the distortion compensator as the feedback signal. Whether the level of an unwanted-wave signal that penetrates the amplifier from space via an antenna is greater than a set level is monitored. If the level of the unwanted-wave signal is above the set level, processing for updating distortion compensation coefficients is suspended. If the level of the unwanted-wave signal is below the set level, then processing for updating distortion compensation coefficients is resumed.

The invention discloses a method for detecting an indoor sound reinforcement device. The method comprises a first step that a DSP processing module controls a controllable output matrix to output a test signal to a speaker array; a second step that a sound pick-up array collects an indoor sound signal and sends the indoor sound signal to an audio analysis module; a third step that the audio analysis module analyzes loudness, phase, frequency response and distortion factor of the sound signal; a fourth step that the DSP processing module calculates a balance degree of the sound field in an indoor environment according to the loudness, calculates delay according to the phase difference, and calculates the matching of the sound built environment and the sound reinforcement device according to the frequency response and the distortion factor; and a fifth step that test results are outputted. The automatic detection function for the indoor sound reinforcement device can be used for bringing standardized and quantified acceptance criteria to acceptance of project and greatly simplifying the acceptance process. The invention is applicable to all indoor sound reinforcement systems.

The invention discloses an image distortion standardization method which is not related to a photo equipment. The method has following steps as: a straight goal line is selected in the image of a photo to be standardized; a starting point A, a midpoint B and an end-point C are respectively selected out on the goal line; the photo coordinates of three pixels (xA, yA), (xB, yB), (xC, yC) are measured, by which a distortion type is calculated. An enough large radius vector delta rb is given to the midpoint B to make the three corrected points A', B' and C' have the opposite distortion type. An assumed image distortion factor is calculated according to the assumed distortion radius vector. According to the assumed image distortion factor, the radius vectors of the three positions A', B' and C' of the three points A, B and C after the distortion is eliminated are calculated. The pixel coordinates of the three positions A', B' and C' after the assumed image distortion is eliminated are calculated. By utilizing a split-middle method, an iterative approach computation is made to get the image distortion factor k1. The method of the invention takes a digital image as a standardization target, breaks away from a camera to calibrate the distortion factor of the digital image (including the historical image and the image in a network transmission, etc.) obtained in various channels.

A system for, and method of, noisy automatic speech recognition employing joint compensation of additive and convolutive distortions and a digital signal processor incorporating the system or the method. In one embodiment, the system includes: (1) an additive distortion factor estimator configured to estimate an additive distortion factor, (2) an acoustic model compensator coupled to the additive distortion factor estimator and configured to use estimates of a convolutive distortion factor and the additive distortion factor to compensate acoustic models and recognize a current utterance, (3) an utterance aligner coupled to the acoustic model compensator and configured to align the current utterance using recognition output and (4) a convolutive distortion factor estimator coupled to the utterance aligner and configured to estimate an updated convolutive distortion factor based on the current utterance using first-order differential terms but disregarding log-spectral domain variance terms.

The invention relates to an electric machine, particularly for a synchronous machine excited by a permanent magnet. The electric machine comprises a rotor arrangement (4) having buried permanent magnets (6) and a stator arrangement (2) having an inner recess (3) for rotationally movably receiving the rotor arrangement (4), the rotor arrangement (4) comprising a plurality of rotor segments (7), each having a pole shoe (10), the outer contour thereof corresponding to an arc contour having a contour radius, the contour radius being smaller than the radius of the rotor arrangement (4), thus forming a gap between two adjacent rotor segments (7), the at least one outer contour of one of the rotor segments (7) having an arc contour designed such that an air gap length ratio of the radial spacingbetween the inner recess (3) and the outer contour along a radial outer boundary of the corresponding rotor segment and the radial spacing between the inner recess and the outer contour along a radial center axis of the corresponding rotor segment (7) is optimized with regard to the distortion factor of the course of the flux density distribution of the pole shoe (10).

The invention discloses a full-power wind power converter used for an electrically excited synchronous generator and belongs to the technical field of wind power generation. The full-power wind power converter comprises a motor side converter, a network side converter and two DC (direct current) side filtering capacitors C1 and C2, wherein the AC (alternating current) input end of the motor side converter is electrically connected with the electrically excited synchronous generator, the DC output end of the motor side converter is electrically connected with the DC bus side of the network side converter through the DC side filtering capacitors, and the AC side of the network side converter is connected with an electric network; the full-power wind power converter also comprises a DC chopper circuit which is connected with the DC bus of the network side converter in parallel; and the motor side converter is a two-quadrant three-level Vienna rectifier, the network side converter is a voltage-type three-level converter which is composed of a power device adopting controllable switches and is of a diode middle point clamping-type topological structure, and the DC side filtering capacitors C1 and C2 are connected in series and then connected with the DC side of the motor side converter in parallel. The full-power wind power converter provided by the invention has the beneficial effects that the distortion factor of the output voltage is effectively reduced, the loss is reduced, the output wave shape quality is good, the cost is saved, the maintenance is convenient.

A particular implementation receives a bitstream and derives parameters from the bitstream. The parameters include quantization parameters, content unpredictability parameters, ratios of lost blocks, ratios of propagated blocks, error concealment distances, motion vectors, durations of freezing, and frame rates. Using these parameters, a compression distortion factor, a slicing distortion factor, and a freezing distortion factor are estimated respectively for distortions resulting from video compression, a slicing mode error concealment, and a freezing slicing mode error concealment. The distortion factors are then mapped to a composite video quality score. For applications with limited computational power, the estimation of distortion factors can be simplified. In particular, the compression distortion factor, the slicing distortion factor, and the freezing distortion factor can be predicted from quantization parameters, ratios of lost blocks, and durations of freezing, respectively.

Disclosed are a method and a system for updating a multi-frequency band pre-distortion coefficient lookup table, in order to solve the problems that the calculation complexity is high. Wherein, the method comprises: collecting a first frequency band reference signal and a first frequency band feedback signal, a second frequency band reference signal and a second frequency band feedback signal; calculating a first frequency band pie-distortion coefficient and a second frequency band pre-distortion coefficient; performing phase calibration on the first frequency band pre-distortion coefficient and the second frequency band pre-distortion coefficient, respectively; and updating a first lookup table according to the first frequency band pre-distortion coefficient performed the phase calibration, and updating a second lookup table according to the second frequency band pre-distortion coefficient performed the phase calibration.