An ultrasound system, probe and method are provided that comprise a transducer with piezoelectric transducer elements polarized in a poling direction, wherein over time one or more of the transducer elements possibly exhibit a depoling effect; and one or more drive circuits configured to: i) generate a transmit signal having at least first polarity segments, the first segments having corresponding first peak amplitudes; ii) generate a repoling signal having a repoling pattern configured to at least partially revert the depoling effect exhibited by the one or more transducer elements; and iii) generate a bias signal in the poling direction, the bias signal combined with the at least one of the transmit signal or the repoling signal to form a corresponding at least one of a biased transmit signal or a bias repoling signal, that is shifted in the poling direction.

A method that includes transmitting coded waveforms simultaneously on multiple elements for several frames, constructing a first multi-input, single output (MISO) system from the codes to model transmit-receive paths, solving system and RF data observation by linear model theory, giving an IR set for the medium, and applying the estimates to a secondary MISO system, constructed by analogy to the first, but with pulses convenient for beamforming in the form of a focused set of single-cycle pulses for ideal focused reconstruction.

Systems and methods for attenuation measuring using ultrasound. In various embodiments, echo data corresponding to a detection of echoes of one or more ultrasound signals transmitted into tissue are received. The echoes can be received from a range of depths of the tissue. Spectral measurements across the range of depths of the tissue are obtained using the echo data. Attenuation characteristics of the tissue across the range of depths of the tissue can be estimated using the spectral measurements across the range of depths of the tissue. Specifically, the attenuation characteristics of the tissue can be estimated using the spectral measurements and known spectral characteristics of the one or more ultrasound signals transmitted into the tissue.

Circuitry for ultrasound devices is described. A multi-level pulser is described, which can support time-domain and spatial apodization. The multi-level pulser may be controlled through a software-defined waveform generator. In response to the execution of a computer code, the waveform generator may access master segments from a memory, and generate a stream of packets directed to pulsing circuits. The stream of packets may be serialized. A plurality of decoding circuits may modulate the streams of packets to obtain spatial apodization.

In an ultrasound imaging system which produces synthetically transmit focused images, the multiline signals used to form image scanlines are analyzed for speed of sound variation, and a map 60 of this variation is generated. In a preferred implementation, the phase discrepancy of the received multilines caused by speed of sound variation in the medium is estimated in the angular spectrum domain for the receive angular spectrum. Once the phase is estimated for all locations in an image, the differential phase between two points at the same lateral location, but different depth, is computed. This differential phase is proportional to the local speed of sound between the two points. A color-coded two- or three-dimensional map 60 is produced from these speed of sound estimates and presented to the user.

Systems and methods for attenuation measuring using ultrasound. In various embodiments, echo data corresponding to a detection of echoes of one or more ultrasound signals transmitted into tissue are received. The echoes can be received from a range of depths of the tissue. Spectral measurements across the range of depths of the tissue are obtained using the echo data. Attenuation characteristics of the tissue across the range of depths of the tissue can be estimated using the spectral measurements across the range of depths of the tissue. Specifically, the attenuation characteristics of the tissue can be estimated using the spectral measurements and known spectral characteristics of the one or more ultrasound signals transmitted into the tissue.

Front-end circuitry for an ultrasound system comprises a beamformer FPGA integrated circuit, transmit ICs with both pulse transmitters and linear waveform transmitters and T/R switches, transmit control and receiver ICs, and analog-to-digital converter (ADC) ICs. Only the transmit ICs require high voltages, and the transmit/receive switches are integrated in the transmit ICs, isolating the receiver ICs from high voltages. The transmitters can be trimmed to adjust the pulse rise and fall rates, enabling the transmission of pulses with low harmonic frequency content and thus better harmonic images.

A probe is described for analyzing a target using an array of transceivers formed of transmitter/receiver pairs. As opposed to the prior art, the high voltage trigger signals from used to trigger the transmitters are separated from the output signals of the receivers thereby resulting in a simpler and more efficient circuitry. Moreover, the output signals are delayed to compensate for the delays in the echo signals from the target due to the varying distance between the different transceivers and the target. The probe can be used for analyzing pathological organs, as well as many other objects such as gas pipes, airplane wings, etc.

Disclosed is a high resolution intravascular ultrasound imaging system including a catheter with a rotatable imaging assembly and an image processor. The image processor in turn features a pulser configured to energize the ultrasound transducer of the rotatable imaging assembly with a multi-frequency ultrasound waveform signal. The image processor further contains a receiver configured to decompose received ultrasound energy as reflected by the target vessel into a plurality of individual subband signals, individually process these signals and reconstitute these signals into a high resolution image of the blood vessel. The IVUS system of the invention may be useful in characterizing cap thickness of vulnerable plaques or other detailed studies of blood vessels.

An ultrasound probe includes a casing, a first transmitting unit, a second transmitting unit and a receiving unit. The first transmitting unit is used for transmitting a first push beam and the first push beam has a first transmitting frequency. The second transmitting unit is used for transmitting a second push beam and the second push beam has a second transmitting frequency. The receiving unit has a receiving frequency and is used for selectively receiving a reflective wave of the first push beam and the second push beam, wherein the receiving frequency is covered with the first transmitting frequency and the second transmitting frequency. The receiving unit, the first transmitting unit and the second transmitting unit are disposed in the casing side by side.