282 results about "Phase congruency" patented technology

An audio signal is conveyed more efficiently by transmitting or recording a baseband of the signal with an estimated spectral envelope and a noise-blending parameter derived from a measure of the signal's noise-like quality. The signal is reconstructed by translating spectral components of the baseband signal to frequencies outside the baseband, adjusting phase of the regenerated components to maintain phase coherency, adjusting spectral shape according to the estimated spectral envelope, and adding noise according to the noise-blending parameter. Preferably, the transmitted or recorded signal also includes an estimated temporal envelope that is used to adjust the temporal shape of the reconstructed signal.

The invention discloses a high-speed weak target flight path detection method of an image field, relating to the field of moving object tracking, and mainly solving the problem of extracting a moving object flight path and a target kinematic parameter from data with a low signal-to-noise ratio. The detection process is as follows: firstly, obtaining a time-Doppler image by mixing and accumulating target multiframe data; carrying out edge extracting on the basis of phase equalization model; carrying out skeletonization and binary image de-noising treatment on the edge detection result with a morphology method to realize edge center positioning as well as noise inhibition; and finally, using a least square method to detect the target flight path and estimate a target parameter. The invention can accurately estimate the advantages of a curve flight path parameter, and can be used for the data processing field for monitoring systems, such as radars and the like to realize high-speed weak target detection and tracking.

The invention discloses an SAR image registration method based on phase congruency and SIFT. The problem that when a traditional SIFT method is applied to synthetic aperture radar, SAR image registration fails or accuracy is low is mainly solved. The method includes the implementing steps of (1) inputting two images, (2) extracting SIFT features, (3) screening feature points, (4) filtering out mismatch point pairs, (5) obtaining geometric deformation parameters and (6) obtaining a registration result. Compared with the prior art, the capacity for filtering out mismatch points is improved, robustness for noise is enhanced, and therefore accuracy of actually measured synthetic aperture radar SAR image registration is improved.

An automated macromolecular method and system for detecting crystals in two-dimensional images, such as light microscopy images obtained from an array of crystallization screens. Edges are detected from the images by identifying local maxima of a phase congruency-based function associated with each image. The detected edges are segmented into discrete line segments, which are subsequently geometrically evaluated with respect to each other to identify any crystal-like qualities such as, for example, parallel lines, facing each other, similarity in length, and relative proximity. And from the evaluation a determination is made as to whether crystals are present in each image.

The invention discloses a method for evaluating medical image quality in combination with phase consistency, gradient magnitude and structural prominence. The method comprises the following steps: 1) calculating a phase consistency map of a reference image and a distorted image by using a log-Gabor wavelet; 2) calculating a gradient magnitude map of the reference image and the distorted image by using a Scharr operator; 3) obtaining a local image quality map in combination with the phase consistency map obtained in the step 1) and the gradient magnitude map obtained in the step 2); 4) calculating a structural prominence map, based on a human eye visual feature, of the reference image; 5) performing weighting summation on the image quality map in the step 3) by using the structural prominence map as an aggregation policy to obtain an image quality score; and 6) when the image quality score is higher than a preset score threshold, judging that the medical image quality is relatively high. The method is relatively high in reliability and high in practicality.

The invention relates to a coaxial-ridge waveguide-microstrip conversion structure ultra-broadband multi-channel power splitter. The input coaxial joint and the extended coaxial waveguide adopt a tapered coaxial gradual transition, and the tapered coaxial gradual transition And the ridge waveguide-microstrip conversion structure can realize ultra-wideband impedance matching; N ridge waveguide-microstrip conversion structures are uniformly distributed along the circumference in the extended coaxial waveguide to realize N-way parallel power division, and the entire power division circuit has axisymmetric To ensure that the signal amplitudes and phases of the N-channel power division signals are equal, the N-channel signal power division can be realized in one step, which can minimize the signal transmission loss. The present invention has ultra-wideband, low transmission loss, can realize any multi-channel power division output, each power division output signal has good amplitude and phase consistency, flat group delay characteristics in the band, and is easy to integrate with other peripheral planar circuits, etc. advantage. The invention is mainly used in microwave and millimeter wave power synthesis amplification systems, array antennas, etc., and has broad application prospects in microwave and millimeter wave systems such as communication and radar.

An automated macromolecular method and system for detecting crystals in two-dimensional images, such as light microscopy images obtained from an array of crystallization screens. Edges are detected from the images by identifying local maxima of a phase congruency-based function associated with each image. The detected edges are segmented into discrete line segments, which are subsequently geometrically evaluated with respect to each other to identify any crystal-like qualities such as, for example, parallel lines, facing each other, similarity in length, and relative proximity. And from the evaluation a determination is made as to whether crystals are present in each image.

A method of tracking a guidewire in video imagery includes: obtaining a first video image including pixels associated with features of a guidewire; selecting a set of parameters to define an open curve on the first video image; determining a feature map of the first video image using phase congruency; and updating the parameters of the open curve using the feature map to align the open curve to the pixels associated with the features of the guidewire.

The invention discloses a correction method and a device of a time division duplex intelligent antenna system, the method comprises that: the initialization of a channel is carried out; the channel correction of the system is started, the correction of a power detection channel and a detection receiving channel is carried out according to the gains of the power detection channel and the detection receiving channel which are obtained under the current working point and the temperature; the gain calibration and the amplitude-phase consistency calibration of an uplink channel are carried out simultaneously at the protection time slot according to the real-time obtained gain of the detection receiving channel and a gain inequality of the detection channel and the detection receiving channel; the gain calibration and the amplitude-phase consistency calibration of a down transmit channel are carried out simultaneously at the downlink pilot time slot according to the obtained target weight value of the downlink transmit channel and the ganged gain regulating quantity of the downlink transmit channel. The invention can effectively solve the key correction problem in the intelligent antenna system, realize the corrections of the gain accuracy and the amplitude-phase consistency errors of the array channel, simplify the algorithm and have the high correction precision.

The invention discloses an amplitude and phase consistency calibration method of multiple channels of a human body security inspection system. The method comprises the following steps that: long-distance calibration and first-time short-range calibration are combined to obtain measuring data of all channels as well as comparison coefficients of all the channels are established; before each case scanning is carried out, short-range calibration at this time is carried out to obtain measuring data of this time of all the channels as well as the comparison coefficients are utilized to correct the measuring data of this time to obtain calibration data of this time; and the calibration data of this time are utilized to carry out normalized calibration on amplitudes and phases of all the channels. According to the invention, the short-range calibration technology and the long-distance calibration technology are combined, so that a problem caused by frequent usage of a long-distance calibrator can be solved; short-range real-time calibration is carried out, so that working stability of the system can be ensured for a long time and thus working efficiency of a human body security inspection system based on millimeter wave active high speed cylindrical rotation three dimensional holographic imaging can be effectively improved.

The invention belongs to the technical field of mobile communication and discloses a 5G large-scale array antenna. The sandwich support plate part is located between a power distribution feed networkpart and a coupling calibration network part. The sandwich support plate part is a local hollow structure. The power distribution feed network part and the coupling calibration network part are connected by signals after welding. The radiating element is composed of several dual-polarized radiating oscillators which are fixedly connected with the power dividing and feeding network. A plurality ofdual-polarized radiators form a sub-array, and each sub-array leads to two dual-polarized channels, which are partially connected with the T / R module. The 5G large-scale array antenna provided by theinvention can still have excellent amplitude consistency and phase consistency under complex signal environment.

An audio signal is conveyed more efficiently by transmitting or recording a baseband of the signal with an estimated spectral envelope and a noise-blending parameter derived from a measure of the signal's noise-like quality. The signal is reconstructed by translating spectral components of the baseband signal to frequencies outside the baseband, adjusting phase of the regenerated components to maintain phase coherency, adjusting spectral shape according to the estimated spectral envelope, and adding noise according to the noise-blending parameter. Preferably, the transmitted or recorded signal also includes an estimated temporal envelope that is used to adjust the temporal shape of the reconstructed signal.

The invention provides an improved 2.4GHz LTCC power divider of which the structure comprises an input port P1, a first output port P2, a second output port P3, a first external side printing ground G1, a second external side printing ground G2, a third external side printing ground G3, an internal ground GND, a ground capacitor C1, an output parallel-connected capacitor C2, a first electric inductor L1, a second electric inductor L2, an isolation resistor R and a printing mark M. Working frequency range is 2.3GHz-2.5GHz, which covers all frequency range of 2.4GHz application. The circuit mode adopted by a common lumped parameter power divider is improved with respect to the structure so that the number of elements is effectively reduced, element value is reduced, and thus the power divider is enabled to be more suitable for batch production of miniaturized devices. The improved 2.4GHz LTCC power divider has substantial advantages of being compact in structure, small in size, high in output isolation, low in insertion loss, great in phase consistency and high in amplitude balance degree.

The invention relates to a method for detecting eye fundus image MA based on phase equalization. The method comprises the steps that firstly, a green channel of a colorful eye fundus image is extracted; then, feature points are extracted based on a phase equalization model, a candidate with the MA is acquired by combining a threshold segmentation and area filtering method; finally, blood vessels and other unrelated information in the image are removed through the method of constructing a gray level profile map, and therefore the true MA is screened out. The advantages of the phase equalization model are fully used, insensitivity on the brightness and the contrast ratio of the image is achieved, enhancement processing does not need to be carried out on an original image, and robustness is good; the blood vessels and other unrelated information are removed through the method of combining the gray level profile map, classification and identification are not involved, the complexity of an algorithm is greatly reduced, operating time is saved, and the MA on the colorful eye fundus image can be efficiently and automatically detected.

The invention discloses a method for rapidly measuring the amplitude and phase consistency of a phased array weather radar. The method for rapidly measuring the amplitude and phase consistency of the phased array weather radar comprises the following steps: 1, testing a transmitting channel, and testing consistency from a waveform controller to the amplitude and phase of the transmitting channel of the antenna, wherein testing contents include (1), measurement of amplitude and phase difference, (2), correction of amplitude and phase, and (3), acquisition of standard of automatic calibration; and 2, testing a receiving channel, and measuring amplitude and phase from an antenna to an intermediate frequency receiving channel, wherein testing contents include (1), measurement of amplitude and phase, (2) correction of amplitude and phase, and (3) acquisition of the standard of automatic calibration. The amplitude difference and the phase difference of the channel can be measured rapidly and simply.

The invention provides a calibration method of accurately testing a polarization component of two perpendicular lines of an antenna. Through the calibration method, the calibration for dual polarizing antenna channel amplitude phase consistency and the improvement of cross polarization performance are achieved. The calibration method of accurately testing the polarization component of the two perpendicular lines of the antenna utilizes the following technical scheme to achieve that a dual polarizing antenna channel is connected with a vector network analyzer and a rotary signal-sending linear polarization auxiliary calibration antenna, two lines of output of a dual polarization probe of a receiving end is transmitted to the vector network analyzer to acquire two time-dependent plural signal curves of polarization channels, and the phase equalization, the amplitude consistency and the cross polarization isolation of the two polarization channels are read according to the two curves. The calibration method of accurately testing the polarization component of the two perpendicular lines of the antenna can be applied to a commonly used dual polarization open waveguide in near-field test calibration, or a commonly used dual polarization antenna in an antenna far-field test, or other dual polarization antennas in application.

The invention discloses an infrared light intensity and polarization image fusion method based on significance migration and detail classification. The method comprises the following steps that: firstly, carrying out NSCT (Non-Subsampled Contourlet Transform) multiscale decomposition on a source image; secondly, carrying out significance detection on a low-frequency component obtained by decomposition, carrying out activity threshold segmentation by a significance image percentile, and determining a significant region; then, migrating the specific low-frequency significant region of polarization into a low-frequency fusion image, taking the rest low-frequency parts as a background region to take a big rule to keep strength information; dividing phase congruency and the threshold of a high-frequency component into an edge outline class and a texture detail class, and independently utilizing the phase congruency and a local standard deviation to fuse two classes of details; and finally, through NSCT inverse transformation, reconfiguring a final fusion image. By use of the method, source image significance bright and dark features and more detail information can be effectively fused into one image, and the method is mainly used for (but is not limited to) the fusion of the infrared light intensity and the polarization image.

The invention relates to a waveguide-micro-strip integrated power distributor-synthesizer. The waveguide-micro-strip integrated power distributor-synthesizer comprises a rectangular waveguide, a medium substrate, a common land being inserted into the medium substrate and two micro-strip probes, wherein the two micro-strip probes are symmetric to each other about the common land and are respectively attached on the upper surface and the lower surface of the medium substrate, the two micro-strip probes are respectively and sequentially connected with two groups of micro-strip line impedance variable sections and two micro-strip transmission lines to form two parallel groups of micro-strip lines which are symmetric to each other about the common land and are respectively located on the upper surface and the lower surface of the medium substrate, the two micro-strip probes are vertically plugged into the rectangular waveguide from an opening on the side wall of a wide edge of the rectangular waveguide along a surface E of the rectangular waveguide, the plugging positions of the two micro-strip probes are symmetric to each other about a central surface of the wide edge of the rectangular waveguide; and a theoretical distance from the central line of each micro-strip probe to a waveguide short-circuited surface in the transmission direction of the rectangular waveguide is a quarter of one waveguide wavelength. The waveguide-micro-strip integrated power distributor-synthesizer has beneficial effects of low loss, wide band, good consistence of amplitudes and phases among different branches, compact structure and easiness in realization.

A method executed by a computer system for detecting edges comprises receiving an image comprising a plurality of pixels, determining a phase congruency value for a pixel, where the phase congruency value comprises a plurality of phase congruency components, and determining if the phase congruency value satisfies a phase congruency criteria. If the phase congruency value satisfies the phase congruency criteria, the computer system categorizes the pixel as an edge pixel. If the phase congruency value does not satisfy the phase congruency criteria, the computer system compares a first phase congruency component of the plurality of phase congruency components to a phase congruency component criteria. If the first phase congruency component satisfies the phase congruency component criteria, the computer system categorizes the pixel as an edge pixel, and if the first phase congruency component does not satisfy the phase congruency component criteria, categorizes the pixel as a non-edge pixel.

The invention discloses a color image quality comprehensive evaluation method. According to the method, first, a to-be-evaluated color image and a corresponding reference image are input; color spacetransformation is performed on the reference image and the to-be-evaluated image, and brightness channel graphs and chrominance channel graphs of the reference image and the to-be-evaluated image areobtained; the chrominance channel graphs of the reference image and the to-be-evaluated image are extracted, and chrominance similarity features are calculated; the brightness channel graphs of the reference image and the to-be-evaluated image are extracted, and log-Gabor wavelets are used to obtain phase-consistent similarity features; position saliency features of the reference image and the to-be-evaluated image are acquired; pooling is performed on the phase-consistent similarity features and the chrominance similarity features through a position saliency feature weighted standard deviation ; and the quality of the to-be-evaluated image is obtained. Through the method, different characteristics of human vision systems are fully considered, the three aspects are reasonably combined, andthe quality of the color image is well evaluated.

The invention discloses an image registering method based on a manifold subspace, comprising the following steps: (1) respectively reading in a target image and a floating image to be registered; (2) respectively calculating the phase consistency of the target image and the floating image to be registered in different scales and directions; (3) fusing information with the phase consistency in different scales and directions by using a manifold subspace method; (4) looking main-phrase consistency information of the target image and the floating image as fuzzy congregation, adopting nearness in fuzzy mathematical, and calculating the fuzzy similarity of the main-phrase consistency information; (5) using the fuzzy similarity of the main-phrase consistency information as an object function, and adopting powell algorithm to search a maximum value of the object function; finishing the registering when the fuzzy similarity reaches maximum. Under the conditions of lower image space resolution, noise influence, and the like, the image registering method has high registering precision and strong robustness.

The invention discloses a video image fusion performance evaluation method based on three-dimensional Log-Gabor conversion. The video image fusion performance evaluation method mainly solves the problem that fusion algorithm performance cannot be evaluated accurately in the prior art under the condition that an input video has noise or background movement. The video image fusion performance evaluation method includes: utilizing the three-dimensional Log-Gabor conversion to perform multi-direction multi-scale decomposition on the input video and a fused video; utilizing three-dimensional phase consistency of a video image to build space-time phase consistency evaluation factors; utilizing three-dimensional Log-Gabor conversion coefficient amplitude to build space-time information extraction evaluation factors; combining the space-time phase consistency evaluation factors and the space-time information extraction evaluation factors to build global space-time performance evaluation factors; and evaluating the video fusion algorithm performance according to calculation results of the factors; and designing partial or global parameters according to a human eye vision standard time-critical success factor (ST-CSF) formula and three-dimensional gradient structure tensor. The video image fusion performance evaluation method based on the three-dimensional Log-Gabor conversion can accurately evaluate the fusion algorithm performance under the condition of noise or background movement and can be used for evaluating video image fusion algorithm performance.

The invention discloses a time digitizer based on a delay ring flop-out method. The time digitizer comprises a start pulse generation module, an end pulse generation module, a start time delay ring, an end time delay ring, a first edge detection module, a second edge detection module, a phase coherence detector and a cycle index counter. A time sequence trigger pulse is shaped to two needed rotary pulse signals by the pulse generation module, the two raising time delay rotary pulse signals of the two rotary pulse signals are detected to be respectively and circularly transmitted in two time delay rings by the first and second edge detector modules, and the cycle indexes of the rotary pulse signals are counted by the cycle index counter at the same time; when the time interval between the two rotary pulse signals is detected to be less than the resolution of the time digitizer by the phase coherence detector, the two time delay rings are off, therefore, the measurement for the time intervals can be finished, and the product of a value of the cycle index counter and the resolution of the time digitizer is a time interval to be detected. The time digitizer provided by the invention is high in measurement resolution, large in measurement range and high in linearity.

A method of tracking a guidewire in video imagery includes: obtaining a first video image including pixels associated with features of a guidewire; selecting a set of parameters to define an open curve on the first video image; determining a feature map of the first video image using phase congruency; and updating the parameters of the open curve using the feature map to align the open curve to the pixels associated with the features of the guidewire.

The invention discloses a videodisc positioning method combining a Gbvs model and a phase consistency. The method comprises the following steps of (1) extracting a green channel of a color eye fundus image; (2) calculating a mask image of the fundus image and acquiring a region of interest (ROI) of the fundus image; (3) extracting three characteristics of brightness, a brightness contrast and the phase consistency; (4) using an improved significant model based on graph (graph based visual saliency, Gbvs) to construct a saliency graph; (5) extracting eye fundus image vein blood vessel skeleton lines and using a least square method to carry out parabola fitting; and (6) comparing significance in a parabola summit neighborhood and an average of significance of a whole eye fundus image and determining a videodisc position. During a process of calculating the saliency graph, according to a characteristic of a videodisc in the eye fundus image, the brightness, the brightness contrast and the phase consistency are extracted, the significant model based on the graph is improved, and during a process of positioning the videodisc, a structure characteristic of the vein blood vessel is used to assist accurate positioning. An experiment proves that the method possesses a good effect.

The invention relates to a digital intermediate-frequency receiver of an ultra high frequency (UHF) river flow rate measuring radar and discloses a digital intermediate-frequency or video phase compensation method. The method for maintaining phase equalization of multichannel receiver by a UHF flow measuring radar includes that a plurality of receiving channels are needed by the UHF flow measuring radar, and an intermediate-frequency signal in each receiving channel has good phase equalization. Phase equalization can be respectively adjusted by simulating automatic gain control (AGC); however, adjustment of phase equalization in the front and the middle of radio frequency and mixing by simulating a circuit is difficult. Phase compensation can be finished through the intermediate-frequency signal when digital downconversion happens, and video signal phases of all ways after downconversion are maintained in consistency. A closed-loop control manner is utilized so that phrase compensation can be finished in a self-adapting mode, and real-time adjustment of consistency of phases of all ways can be achieved. Even the radar is in operation, detection and rectification can be performed in a short time. The method for maintaining phase equalization of multichannel receiver by the UHF flow measuring radar solves the problem that phase inconsistency of signals received by the flow measuring radar affects subsequent signal processing and data processing, and errors of a radar measuring system are reduced. Loop self-adaptation control of the whole process is utilized, phase differences among the channels are compensated, and an intelligent effect is achieved.

The invention belongs to the field of underwater acoustic transducers, in particular to a method for measuring the amplitude and phase consistency of a linear hydrophone array. The invention includes mechanically fixing the hydrophone array on the lifting device, the lifting device lifts the hydrophone array up and down at a fixed interval, hangs the transmitting transducer at a certain distance from the hydrophone array, and the distance meets the requirements of the transducer. The far-field distance from the hydrophone, the hanging depth of the transmitting transducer is the same as the depth of the hydrophone at the top of the hydrophone array; the hydrophone array and the lifting device are mechanically fixedly connected, during the lifting process, the hydrophone array Always remain vertical with no horizontal wobble or movement. The invention adopts the method of moving the hydrophone in the vertical direction, which avoids the phase error caused by the distance error in the horizontal direction caused by moving the hydrophone in the horizontal direction or re-hanging the hydrophone during the consistency measurement of the traditional hydrophone.

The invention provides 8x8 high-precision broadband millimeter-wave matrix switches and a parameter evaluation and calibration method. Switch minimization and link symmetry design is adopted for radio-frequency links, symmetric uplink and downlink link channels are designed, each channel realizes 8x8=64 independent radio-frequency links, each channel is formed by cascading of four SP4T microwave switches and two SPDT microwave switches, and a comb-shaped cross-cascading connection manner of semi-rigid coaxial cables is adopted among the switches; and a good port impedance matching characteristic of the matrix switches in an entire broadband frequency band of DC-40GHz can be guaranteed, radio-frequency channel loss is lowest, precision of radio-frequency channel amplitude consistency and phase consistency is high, the matrix switches have the advantages of high performance, small volume, automation and the like, a product design and debugging process is standardized and automated, and aresearch and development cycle of batch products is greatly shortened.

The invention discloses a Ka wave band flat plate gap array antenna monopulse feed network. The feed network is composed of parts such as a radiation gap feed layer, a power distribution network, a monopulse network and the like, wherein the power distribution network adopts a feed waveguide broadside opening inclined joint form, and is used for carrying out coupling feed on the radiation gap feed layer and controlling the feed power through adjusting a feed waveguide centre gap tilt angle; the monopulse network adopts four flat surface magic Ts to form a sum and difference channel in a bell socket manner, and is used for feeding to the power distribution network through a coupling gap, and each flat surface magic T is provided with an inverted-step-shaped metallic membrane, which is used for carrying out voltage standing wave ratio distribution and improving standing wave band width and amplitude-phase consistency band width of each magic T; and coupling folded wave guide is adopted, thus the array radiation gaps are arranged at the same interval, the distance between the last feed inclined joint and the short-circuit end is 1 / 2 waveguide wavelength, and the problem of mutual interference among feed waveguides is solved.

A radio base station has at least two radio chains and a precoder for precoding information symbols by a precoding matrix for multi-antenna transmission to a number of user equipment terminals. Precoding matrix statistics representative of phase coherency between at least two radio chains is compiled based on feedback information representative of preferred precoding matrix from one or more user equipment terminals (S1). A relative phase error is then detected between radio chains based on the compiled precoding matrix statistics (S2). It is then possible to compensate or otherwise adjust for the detected relative phase error (S3) based on the compiled precoding matrix statistics.