This invention provides a signal-processing method that makes it possible to acquire, relatively easily and surely, a highly reliable normalized impulse-response signal without relying on the signal-correction processing after normalization. The signal-processing method of this invention includes a low-frequency extraction step, a high-frequency extraction step and a synthesizing step. In the low-frequency extraction step, only the low-frequency component is extracted from the spectrum of the first normalized signal NS1 obtained by normalizing the target signal S.sub.tgt in the time domain. In the high-frequency extraction step, only the high-frequency component is extracted from the spectrum of the second normalized signal NS2 obtained by normalizing the target signal S.sub.tgt in the frequency domain using the reference signal S.sub.ref. In the synthesizing step, the low-frequency component, derived from the first normalized signal NS1, and the high-frequency component, derived from the second normalized signal NS2, are synthesized to obtain a normalized impulse-response signal NS.

The present disclosure relates to an acoustic position determination system that includes a mobile communication device and at least one base transmitter unit. The mobile communication device is configured to transmit and receive acoustic signals. Due to relative movements between the mobile communication device and the base transmitter unit, frequencies of the received signals shift due to Doppler effect. The mobile communication device is configured to compensate Doppler frequency shifts in the received acoustic signals prior to performing a deconvolution decoding process. The mobile communication device is further configured to compensate Doppler frequency shifts and perform deconvolution decoding process on acoustic signals received from multiple signal transmission paths.

A system and method for capturing ultrasound signals from a hemispheric imaging region (e.g., by a stationary array of transducer elements arranged in the shape of a faceted hemisphere) and estimating scattering measurements that would be made by a virtual array in the opposite hemisphere (e.g., by a network of processors that receive and process the transmitted ultrasound signals in parallel) by forming an initial estimate of a medium variation for each of a plurality of subvolumes in the scattering object to form an estimated object, calculating residual scattering by using a difference between a scattering response calculated for the estimated object and measured ultrasound signals received from the scattering object, forming an initial three-dimensional image of the scattering object, and extrapolating a difference between the scattering response calculated for the estimated object and the measured ultrasound signals received from the scattering object.

This disclosure provides a system and method for producing ultrasound images based on Full Waveform Inversion (FWI). The system captures acoustic/(an)elastic waves transmitted through and reflected and/or diffracted from a medium. The system performs an FWI process in a time domain in conjunction with an accurate wave propagation solver. The system produces 3D maps of physical parameters that control wave propagation, such as shear and compressional wavespeeds, mass density, attenuation, Poisson's ratio, bulk and shear moduli, impedance, and even the fourth-order elastic tensor containing up to 21 independent parameters, which are of significant diagnostic value, e.g., for medical imaging and non-destructive testing.

The ultrasonic diagnostic apparatus according to the present embodiment includes a frequency characteristic analysis circuit, a filter setting circuit, and a filter processing circuit. The frequency characteristic analysis circuit performs a frequency analysis on a first reception signal corresponding to a region of interest of each depth, and acquires a frequency characteristic of each depth. The filter setting circuit sets a reception filter of each depth based on the acquired frequency characteristic of each depth such that the acquired frequency characteristic of each depth shows a predetermined frequency characteristic. The filter processing circuit applies the set reception filter of each depth to a second reception signal corresponding to the region of interest of each depth, the second reception signal being after the first reception signal, and converts the second reception signal into a third reception signal corresponding to the region of interest of each depth.

Systems and methods for generating adaptive contrast accumulation imaging images are disclosed. A point spread function thinning/skeletonization technique may be performed on contrast enhanced image frames. An aggressiveness parameter of the technique may be adapted temporally and/or spatially. The aggressiveness parameter may be adapted based on various factors, including, but not limited to, time since injection of the contrast agent, signal intensity, and/or vessel size. The images may be temporally accumulated to generate a final sequence of adaptive contrast accumulation imaging images.

The invention provides methods and systems for generating an ultrasound image. In a method, the generation of an ultrasound image comprises: obtaining channel data, the channel data defining a set of imaged points; for each imaged point: isolating the channel data; performing a spatial spectral estimation on the isolated channel data; and selectively attenuating the spatial spectral estimation channel data, thereby generating filtered channel data; and summing the filtered channel data, thereby forming a filtered ultrasound image. In some examples, the method comprises aperture extrapolation. The aperture extrapolation improves the lateral resolution of the ultrasound image. In other examples, the method comprises transmit extrapolation. The transmit extrapolation improves the contrast of the image. In addition, the transmit extrapolation improves the frame rate and reduces the motion artifacts in the ultrasound image. In further examples, the aperture and transmit extrapolations may be combined.

In backscatter coefficient imaging, a backscatter coefficient of one region of interest relative another region of interest is used to avoid calibration. The system effects are removed by using a frequency-dependent measure of the backscatter. The relative frequency-dependent backscatter coefficient is determined by an ultrasound scanner.

The present disclosure relates to an acoustic position determination system that includes a mobile communication device and at least one base transmitter unit. The mobile communication device is configured to transmit and receive acoustic signals. Due to relative movements between the mobile communication device and the base transmitter unit, frequencies of the received signals shift due to Doppler effect. The mobile communication device is configured to compensate Doppler frequency shifts in the received acoustic signals prior to performing a deconvolution decoding process. The mobile communication device is further configured to compensate Doppler frequency shifts and perform deconvolution decoding process on acoustic signals received from multiple signal transmission paths.

Methods and systems are provided for color flow ultrasound imaging. In one embodiment, a method comprises acquiring color flow data, detecting, with a neural network, a flash artifact in the color flow data, adjusting an adaptive filter cutoff of a clutter filter based on a classification result of the neural network, filtering, with the clutter filter, the flash artifact from the color flow data, and displaying a color flow image generated from the filtered color flow data. In this way, strong flash artifacts caused by strong tissue movement or probe movement may be dynamically suppressed during color flow ultrasound imaging.