Systems, devices, and methods for sparse synthetic aperture ultrasound (SSAU) imaging and/or range-Doppler applications are described. An example method for SAU imaging includes receiving, via a user interface, an input including an array topology comprising a particular N-dimensional arrangement of a plurality of transducer elements of the SAU system, an objective space, a function characterizing an imaging capability of the SAU system, and one or more constraints, generating, based on the input, an acoustic field over the objective space for each of the plurality of transducer elements of the array topology, selecting one or more transducer elements from the plurality of transducer elements of the array topology based on evaluation of the function, and providing for display, on the user interface, the selected one or more transducer elements that satisfy each of the one or more constraints.

Ultrasound signal processing device including: transmitter performing transmission events while varying a focal point; receiver generating, for each transmission event, receive signal sequences for transducer elements; delay-and-sum calculator generating, for each transmission event, a sub-frame acoustic line signal including an acoustic line signal for each measurement point located on target lines passing through the focal point and composing a target line group; and synthesizer combining sub-frame acoustic line signals to generate a frame acoustic line signal. The target lines are straight lines, and any measurement point, on any target line, that is spaced away from the focal point by a predetermined distance or more satisfies a condition that distance between the measurement point and a most nearby measurement point on the same target line is smaller than distance between the measurement point and a most nearby one among measurement points on an adjacent target line.

Methods for contrast-enhanced ultrasound imaging that implement coded multi-pulses in each of two or more different transmission events are described. Data acquired in response to the two different transmission events are decoded and combined. In some embodiments, the coded multi-pulses include two or more consecutive Hadamard encoded ultrasound pulses. In other embodiments, multiplane wave pulses can be used. Such multiplane wave pulses can be coded using Hadamard encoding, as one example. In addition, the multiplane wave pulses can be further coded using amplitude modulation, pulse inversion, or pulse inversion amplitude modulation techniques.

An ultrasound diagnostic apparatus according to an embodiment includes an ultrasound probe, and processing circuitry. The ultrasound probe performs transmission of ultrasonic pulses of different polarities to different transmission positions of a subject for multiple times. The processing circuitry performs, for each of the different polarities, reception beam-forming processing with respect to plural reception signals acquired by transmission of plural ultrasonic pulses of an identical polarity. The processing circuitry extracts a non-linear signal by adding up reception signals of the different polarities at an identical reception position, the signals subjected to reception beam forming.

A first synthesis unit generates a first synthetic image by applying a first weight distribution to a plurality of sub-images and then synthesizing the sub-images. A second synthesis unit generates a second synthetic image by applying a second weight distribution to the plurality of sub-images and then synthesizing the sub-images. A generation unit generates a display image based on the first synthetic image and the second synthetic image.

A method for ultrasound imaging a target region including: (a) transmitting a tracking beam from at least a subset of the elements of the array to the region, each of the subset of the elements emitting a signal of the tracking beam with a respective transmission time shift; (b) receiving echo signals at at least some of the subset of the elements of the array, each echo signal being responsive to the tracking beam; (c) applying the time shift to at least some of the subset of the respective elements to the echo signals received at corresponding elements; (d) modifying the time shift and repeating (a)-(c) to provide an ultrasound dataset representing a recovered source element domain; (e) focusing and beamforming the dataset to map time signals of the dataset and combine channel signals to provide spatial pixel data; and (f) forming an ultrasound image from the spatial pixel data.

Disclosed is an imaging method for producing an image of a region inside a medium by an array of transducers, including the a transmission step of a plurality of waves inside the medium, a reception step for acquiring a set of data, a beamforming step providing a plurality beamformed pixel values depending on various transmit weighting vectors, and a combining step for combining the beamformed pixel values into a pixel value of each pixel in the image. The transmit weighting vectors are different and orthogonal one to another one.

A reception beamformer 140 includes a delay-and-sum unit 142 that performs delay-and-sum processing with respect to reception signal sequences from multiple channels based on reflected ultrasound to calculate acoustic line signal line data. The delay-and-sum unit 142, in first reception beamforming processing, synthesizes the acoustic line signal line data calculated in the delay-and-sum processing by summing acoustic line signals associated with the observation points having the same positions, and, in the second reception beamforming processing, outputs the acoustic line signal data calculated in the delay-and-sum processing as is. Time taken by the delay-and-sum unit 142 to generate the acoustic line signal line data per set of acoustic line signal line data is equal or approximately equal in the first reception beamforming processing and the second reception beamforming processing.

Techniques, systems, and devices are disclosed for synthetic aperture ultrasound imaging using a beamformer that incorporates a model of the object. In some aspects, a system includes an array of transducers to transmit and/or receive acoustic signals at an object that forms a synthetic aperture of the system with the object, an object beamformer unit to (i) beamform the object coherently as a function of position, orientation, and/or geometry of the transducers with respect to a model of the object, and (ii) produce a beamformed output signal including spatial information about the object derived from beamforming the acoustic echoes; a data processing unit to process data and produce an image of the object based on a rendition of the position, the orientation, the geometry, and/or the surface properties of the object, relative to the coordinate system of the array, as determined by the data processing unit.

Techniques, systems, and devices are disclosed for synthetic aperture ultrasound imaging using spread-spectrum, wide instantaneous band, coherent, coded waveforms. In one aspect, a method includes synthesizing a composite waveform formed of a plurality of individual orthogonal coded waveforms that are mutually orthogonal to each other, correspond to different frequency bands and including a unique frequency with a corresponding phase; transmitting an acoustic wave based on the composite waveform toward a target from one or more transmitting positions; and receiving at one or more receiving positions acoustic energy returned from at least part of the target corresponding to the transmitted acoustic waveforms, in which the transmitting and receiving positions each include one or both of spatial positions of an array of transducer elements relative to the target and beam phase center positions of the array, and the transmitted acoustic waveforms and the returned acoustic waveforms produce an enlarged effective aperture.