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.

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.

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 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 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.

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 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.