13 results about "Doppler imaging" patented technology

The invention discloses a 3D human body posture estimation method based on a millimeter wave radar, and relates to the technical field of 3D human body postures. The invention provides a symbol perception energy separation mechanism by introducing a SignAware module and aiming at the problem of information annihilation caused by mixing of positive and negative Doppler components in the prior art, and according to the design, inductive bias consistent with a Doppler imaging physical mechanism is injected into a network structure, so that the model is constrained to follow the dynamic law of a speed symbol, and the model is more accurate and reliable. And separable positive and negative subspaces are formed in the representation space. Therefore, cross-symbol interference is reduced, the alignability and interpretability of specific joint movement are improved, and the sensitivity to speed polarity is kept in a complex multi-joint scene; a PhaseFilm module is provided, aiming at the defect that an existing method lacks periodic and sequential modeling, a phase conditional feature re-calibration mechanism is introduced, the two modules are put into an attitude network, then a feature extraction mechanism combining a time domain and a frequency domain is introduced, and a final SPTFormer network is obtained.

The application discloses a micro blood flow imaging method based on adaptive density filtering and a related device, and relates to the technical field of ultrasonic imaging. The method comprises the following steps: extracting a static frame in original ultrasonic data, screening a high-quality static frame through correlation analysis to eliminate motion interference; performing SVD clutter filtering, and cutting off high spatiotemporal coherence singular values to separate tissue clutter and microbubble signals; performing adaptive density filtering and subtracting a preliminary filtering result to realize noise suppression and overlapping microbubble decoupling; and enhancing microbubble motion signals through time-lag autocorrelation processing, and finally completing power Doppler imaging and ultrasonic localization microscope reconstruction. The scheme effectively solves the problem that the prior art cannot simultaneously consider PDI noise suppression and ULM microbubble decoupling, significantly improves image signal-to-noise ratio and super-resolution, avoids problems such as signal distortion, artifacts and loss of low-speed blood flow, and provides more reliable imaging support for clinical diagnosis such as blood vessel lesion detection and tumor blood flow evaluation.

The application provides a kind of space target ISAR image component intelligent segmentation and attitude estimation method, through inverse synthetic aperture radar to space target is continuously observed, and utilize distance-Doppler imaging algorithm to the echo is sequentially imaged, obtain the ISAR image sequence of space target;Utilize deep learning network Pix2pixGAN to the ISAR image sequence is segmented, and the segmentation accuracy is higher;After removing the invalid connected region in each component segmentation result, obtain the final segmentation image of each component;Linear structure extraction is carried out to the final each component segmentation image using the minimum circumscribed rectangle method, and the method is lower to the image component segmentation accuracy requirement, and the robustness is stronger;Finally, according to the imaging principle of radar observation and ISAR image, an unconstrained optimization problem for solving three-dimensional attitude is constructed, and a particle swarm optimization algorithm is used for solving, and the solving efficiency is higher, to realize the attitude inversion of space target key component.

The invention discloses a method for improving the color Doppler signal-to-noise ratio of deep peripheral pancreatic vessels, and relates to the technical field of medical ultrasonic imaging. According to the method, the signal penetrating power is enhanced and the original data quality is optimized by combining coding excitation and matched filtering with self-adaptive space composite imaging at the front end, and blood flow signals are intelligently extracted through self-adaptive clutter suppression and a deep learning model in sequence at the rear end and are finally fused and displayed with a B-mode image. According to the method, the problem of extremely low signal-to-noise ratio of deep peripancreatic vessel color Doppler imaging caused by serious signal attenuation and background noise interference is systematically solved. According to the method, the detection capability of deep low-speed blood flow signals can be effectively enhanced within a safety limit value, clearer and more accurate blood flow images are obtained, dependence on experience of an operator is reduced, and the diagnosis reliability is improved.

The invention discloses a precession target scattering center separation method based on a three-dimensional radar data cube, and the method comprises the steps: carrying out the processing of a radar echo pulse signal of a conical precession target, and building a precession model of the target, so as to distinguish the different signal characteristics of a local scattering center and a sliding scattering center; carrying out two-dimensional distance-Doppler imaging on the radar echo signal, arranging multiple frames of obtained distance-Doppler images according to a time sequence within a preset imaging time, and constructing a distance-Doppler image sequence; based on a feature enhancement method of a binary mask, automatically separating data of a local scattering center and a sliding scattering center from the distance-Doppler image sequence, extracting coordinate information of each scattering center, and generating a three-dimensional radar data cube containing distance, frequency and time dimensions; and performing trajectory tracking and separation on the sliding scattering center signal in the three-dimensional radar data cube by using a three-dimensional optimal path selection method.

This invention discloses a refined ISAR imaging method based on frequency-modulated plane fitting, belonging to the field of radar signal processing and target imaging technology. This invention can automatically identify and eliminate outliers generated by noise during feature extraction, using only interior points conforming to rigid body motion laws for parameter calculation. Through the established planar constraints, this invention can simultaneously decouple and accurately estimate rotational angular velocity and angular acceleration, solving the problem of inaccurate parameter estimation caused by neglecting geometric constraints between scattering points in traditional methods. Combining the estimated accurate motion parameters, this invention uses the PFA algorithm to replace the traditional range-Doppler imaging algorithm. This not only eliminates azimuth defocus caused by angular acceleration but also effectively corrects cross-range cell movement and image geometric distortion caused by large rotation angles or long accumulation times, significantly improving the spatial resolution and geometric fidelity of the imaging.

The ultrasonic imaging device comprises an ultrasonic probe and an operating handle, the ultrasonic probe comprises a sheathing canal, an energy converter arranged in the sheathing canal, a torsion piece at least partially located in the sheathing canal and a connecting piece connecting the torsion piece and the energy converter, and the energy converter comprises a plurality of array elements. The operating handle is connected with the torsion part and used for manually driving the torsion part to twist, and when the torsion part twists, the transducer can be driven to rotate through the connecting part. When the ultrasonic probe is used, the transducer only needs to be manually driven by the operating handle to rotate so as to find the optimal scanning direction, high-speed rotation is not needed, the ultrasonic probe can carry out Doppler imaging, especially Doppler blood flow can be observed, a doctor can carry out clinical diagnosis conveniently, and the cost of a patient can be saved.

The application relates to the technical field of laser radar, in particular to a multi-channel synthetic aperture laser radar imaging method and system based on motion compensation, which comprises the following steps: acquiring echo data of multiple receiving channels; performing distance pre-processing on the echo data to obtain multi-channel echo data focused in the distance direction; setting a tentative speed based on the multi-channel echo data and calculating corresponding azimuth ambiguity signal ratio (AASR); performing MAASR search in a preset speed range to determine a target radial velocity true value; constructing a motion compensation phase factor according to the target radial velocity true value and performing phase correction processing on the multi-channel echo data; performing multi-channel spectrum reconstruction, space-time adaptive processing, full-bandwidth spectrum splicing and distance Doppler imaging processing on the multi-channel echo data after phase correction, and outputting a high-resolution wide-surveying-band image. The application can maintain correct phase relationships among multi-channel echoes in the presence of target motion influence, and realize stable and reliable imaging.

The invention discloses a Doppler imaging method and device based on Spearman rank correlation and a medium. The method comprises the following steps: acquiring beam forming radio frequency data generated in a Doppler imaging process of a target area; calculating a signal power diagram and a noise power diagram of the beam forming radio frequency data; and inputting the signal power diagram and the noise power diagram into an optimized and trained noise coefficient adjustment network, outputting a pixel-level noise coefficient to correct the beam synthesis radio frequency data, and obtaining an enhanced image of the target area. The network loss function comprises Spearman rank correlation loss which is used for maximizing the Spearman rank correlation between noise coefficient adjustment network output and 1-gCF; the signal power constraint loss is used for maximizing the original beam forming radio frequency data intensity reserved by the imaging result of the area specified by the gCF; gCF is a generalized coherence factor. According to the method, the noise suppression capability and the signal retention capability during complex tissue Doppler imaging are optimized, and the imaging effect is improved.

A system and method for synthesizing a fetal heartbeat. A sequence of ultrasound images of a fetus, acquired in a non-Doppler imaging mode and capturing a heart of the fetus, is received and processed to generate an audio signal representative of the heartbeat of the fetus.

The application discloses a kind of unknown figure target to continuous dual-frequency laser Doppler imaging detection method, comprising the following steps.Step one: using dual-frequency laser coherent detection principle and digital micro-mirror array (DMD) to modulate echo signal;Step two: the echo signal containing Doppler frequency shift value after modulation and local signal are mixed and filtered;Step three: Fourier transform is carried out to filtered time-domain signal respectively and frequency domain processing is carried out to obtain the observation value of compressed sensing reconstruction algorithm;Step four: the Doppler frequency shift of moving object is recovered using compressed sensing reconstruction algorithm, to realize Doppler imaging detection.The application combines compressed sensing and dual-frequency laser detection technology, proposes a new Doppler imaging detection signal processing method, which can improve measurement accuracy, effectively reduce the number of signal acquisition measurements, speed up data processing and imaging speed.

The invention discloses an intelligent interference identification method based on radar distance-Doppler imaging characteristics, and relates to the technical field of radar signal processing. Comprising the following steps: performing feature extraction on radar distance-Doppler two-dimensional image data to obtain initial features; performing normalization processing on the initial features to obtain a training sample set and a test sample set; inputting the training sample set into a support vector machine model for training, and determining optimal parameters of the model by adopting grid search based on cross validation to obtain a trained support vector machine model; and inputting the test sample set into the trained support vector machine model to obtain an identification result. The method is used for solving the problem that a traditional signal detection method is difficult to distinguish target echoes and interference echoes.

The invention relates to the technical field of laser radars, in particular to a multi-channel synthetic aperture laser radar imaging method and system based on motion compensation, and the method comprises the steps: obtaining echo data of a plurality of receiving channels; performing range-direction preprocessing on the echo data to obtain range-direction focused multi-channel echo data; setting a tentative speed based on the multi-channel echo data and calculating a corresponding azimuth ambiguity signal ratio (AASR), and executing MAASR search in a preset speed range to determine a target radial speed true value; constructing a motion compensation phase factor according to the target radial velocity truth value and executing phase correction processing on the multi-channel echo data; and performing multi-channel frequency spectrum reconstruction, space-time adaptive processing, full-bandwidth frequency spectrum splicing and distance Doppler imaging processing on the multi-channel echo data after phase correction, and outputting a high-resolution wide-swath image. According to the invention, a correct phase relation among multi-channel echoes can be maintained under the condition that the target motion influence exists, and stable and reliable imaging is realized.