A method for reconstructing a signal from a subset of the full signal is disclosed. In one embodiment, the method includes receiving a plurality of randomly sampled multichannel radio-frequency or in-phase and quadrature signals acquired from a physical environment including a transmitter, a propagation medium and a receiver; modelling the full signal as a matrix comprising a plurality of vector signals wherein the full signal is expressed as a matrix product of a first matrix and a second matrix; updating the second matrix based on an objective function to produce an updated second matrix; determining a convergence parameter in dependence upon the evaluated objective function; and modifying the updated second matrix in dependence upon the convergence parameter.

A rotational intravascular ultrasound probe for insertion into a vasculature and a method of manufacturing the same. The rotational intravascular ultrasound probe comprises an elongate catheter having a flexible body and an elongate transducer shaft disposed within the flexible body. The transducer shaft comprises a proximal end portion, a distal end portion, a drive shaft extending from the proximal end portion to the distal end portion, an ultrasonic transducer disposed near the distal end portion for obtaining a circumferential image through rotation, and a transducer housing molded to the drive shaft and the ultrasonic transducer.

A method for reconstructing a signal from a subset of the full signal is disclosed. In one embodiment, the method includes receiving a plurality of randomly sampled multichannel radio-frequency or in-phase and quadrature signals acquired from a physical environment including a transmitter, a propagation medium and a receiver; modelling the full signal as a matrix comprising a plurality of vector signals, wherein the full signal is expressed as a matrix product of a first matrix and a second matrix; updating the second matrix based on an objective function to produce an updated second matrix; determining a convergence parameter in dependence upon the evaluated objective function; and modifying the updated second matrix in dependence upon the convergence parameter.

In one embodiment, a method includes transmitting, from a first transducer of an electronic device, a first audio signal to a surface near the electronic device. The first audio signal is generated based on a frequency sweep across a range of frequencies. The method also includes receiving, at a second transducer of the electronic device, a second audio signal that is at least partly reflected off the surface. The method then determines an attribute of the surface based on the received second audio signal.

A 3D ultrasonic diagnostic imaging system produces 3D display images at a 3D frame rate of display which is equal to the acquisition rate of a 3D image dataset. The volumetric region being imaged is sparsely sub-sampled by separated scanning beams. Spatial locations between the beams are filled in with interpolated values or interleaved with acquired data values from other 3D scanning intervals depending upon the existence of motion in the image field. A plurality of different beam scanning patterns are used, different ones of which have different spatial locations where beams are located and beams are omitted. In a preferred embodiment the determination of motion and the consequent decision to use interpolated or interleaved data for display is determined on a pixel-by-pixel basis.

A rotational intravascular ultrasound probe for insertion into a vasculature and a method of manufacturing the same. The rotational intravascular ultrasound probe comprises an elongate catheter having a flexible body and an elongate transducer shaft disposed within the flexible body. The transducer shaft comprises a proximal end portion, a distal end portion, a drive shaft extending from the proximal end portion to the distal end portion, an ultrasonic transducer disposed near the distal end portion for obtaining a circumferential image through rotation, and a transducer housing molded to the drive shaft and the ultrasonic transducer.

A rotational intravascular ultrasound probe for insertion into a vasculature and a method of manufacturing the same. The rotational intravascular ultrasound probe comprises an elongate catheter having a flexible body and an elongate transducer shaft disposed within the flexible body. The transducer shaft comprises a proximal end portion, a distal end portion, a drive shaft extending from the proximal end portion to the distal end portion, an ultrasonic transducer disposed near the distal end portion for obtaining a circumferential image through rotation, and a transducer housing molded to the drive shaft and the ultrasonic transducer.

Estimation and imaging of linear and nonlinear propagation and scattering parameters in a material object where the material parameters for wave propagation and scattering has a nonlinear dependence on the wave field amplitude. The methods transmit at least two pulse complexes composed of co-propagating high frequency (HF) and low frequency (LF) pulses along at least one LF and HF transmit beam axis, where said HF pulse propagates close to the crest or trough of the LF pulse along at least one HF transmit beam, and where one of the amplitude and polarity of the LF pulse varies between at least two transmitted pulse complexes. At least one HF receive beam crosses the HF transmit beam at an angle, to provide at least two HF cross-beam receive signals from at least two transmitted pulse complexes with different LF pulses.

A navigation-communication-integrated metamaterial sonar for underwater vehicles is provided, and belongs to the field of ocean detection and communication. The metamaterial sonar is a metamaterial composite structure including a group of disc array with the same diameters, a disc backboard and water gaps. By adjusting the period p of the disc array, a board thickness t1 of each disc, the thickness g of each water gap, the radius w.sub.1 of the disc array, the radius w.sub.2 and the thickness t.sub.2 of the backboard, the working states of underwater navigation and underwater acoustic communication may be flexibly switched by changing working frequencies, and the navigation-communication-integrated sonar may be realized.

Methods and systems are provided that perform baseband beamforming of ultrasound signals. The methods and systems obtain receive signals from transducers of an ultrasound probe and demodulate the receive signals to obtain complex receive signals having in-phase (I) and quadrature (Q) components. The methods and systems apply time delay and phase correction to the complex receive signals to form delayed complex receive signals before summing the delayed complex receive signals to produce a coherent receive signal. The phase correction includes applying coarse and fine corrections where the coarse correction is calculated as a multiple of a sampling time and the fine correction is calculated as a fraction of the sampling time. The methods and systems apply the coarse and fine corrections contemporaneously by multiplying the complex receive signal by a complex carrier delayed by a multiple of the sampling time and delayed by the fraction of the sampling time.