An ultrasound probe has a two dimensional matrix array transducer and a digital microbeamformer. The microbeamformer comprises a plurality of transmitters and amplifiers coupled to elements of the array transducer, a plurality of low power analog to digital converters and digital beamforming circuitry coupled to the amplifiers, a microbeamformer controller, a power supply and a USB controller which cumulatively consume three watts or less.

In some examples, received signals from certain multilines may be selectively filtered to remove aliased frequencies that may result in grating lobes in ultrasound images. In some examples, a transmit beam may be shaped to reduce spatial frequencies in received signals. In some examples, the width of the transmit beam may be adjusted based on a frequency of the transmit signal. In some examples, a focal depth of the transmit beam may be adjusted based on a frequency of the transmit signal.

A delay line control circuit includes a pseudo-random number generator and a random phase generator circuit coupled to the pseudo-random number generator. The pseudo-random number generator is configured to produce a predetermined sequence of pseudo-random values. The random phase generator circuit is configured to randomize an access sequence for capacitors of a delay line. The random phase generator circuit includes a sequence register, an adder, and gating circuitry. The sequence register is configured to a store a value identifying one of the capacitors to be accessed. The adder is coupled to the sequence register, and is configured to increment the value stored in sequence register. The gating circuitry is coupled to the pseudo-random number generator and the adder. The gating circuitry is configured to pass one of the pseudo-random values to the adder for addition to the value stored in the sequence register.

For ultrasound imaging using a matrix transducer, interconnects or switches are provided to allow sub-arrays forming a 1D array, such as with sub-arrays one element wide with the maximum number of elements in elevation. Where groups are used to limit the switches and available system channels per group, an extra switch may connect between elements of different groups through a group output to extend a sub-array across groups. To further limit the number of switches, the group may be sub-divided where different combinations of sub-groups are connectable with different combinations of the system channels for the group.

For estimating attenuation, diffraction effects are corrected by transmitting at different frequencies using apertures sized to match the on-axis intensity profile and/or resolution cell size between the transmissions where there is no attenuation. Attenuation causes a variance in return. A rate of change is estimated from a ratio of the magnitude of the signals or displacements responsive to the transmissions. The attenuation is calculated from the rate of change over depth of the ratio.

An ultrasound system produces high quality images at a high framerate of display. A plane or volume to be imaged is scanned by different diverging transmit beams to acquire a series of different sub-frames, the number of sub-frame acquisitions comprising a total number of transmit beams which would produce a high quality image. The echoes received in response to the transmit beams of a sub-frame are coherently combined with the echoes received in other sub-frames. Each time the echoes of a new sub-frame have been coherently combined with the echoes of all other different sub-frames, a full image is produced. After a complete series of sub-frames has been received and the echoes combined, another series of sub-frame acquisition is commenced and a new series of sub-frames acquired. As each new sub-frame is acquired, it is coherently combined with all the other different and most recently acquired sub-frames. This technique produces a new image at the sub-frame scanning rate, rather than awaiting a completely new series of sub-frames before forming a new image.

The present disclosure provides an ultrasound imaging system comprising an array of transducer elements, a plurality of receive circuits configured to provide one or more output signals, a plurality of delay circuits configured to output one or more delayed signals, and at least one multi-channel beamformer configured to (i) receive representations of a plurality of microbeamformed signals and (ii) output at least one representation of a beamformed signal. The plurality of microbeamformed signals may represent a combination of delayed signals from the plurality of delay circuits. The plurality of delay circuits may be characterized by a plurality of time delay values. The plurality of time delay values may be controllable or adjustable such that one or more points-of-focus characterizing the microbeamformed signals can move along a line of sight.

An ultrasound probe contains an array transducer and a microbeamformer coupled to elements of the array. The microbeamformer comprises analog to digital converters and digital beamforming circuitry for at least thirty-two digital channels in the microbeamformer. Preferably the analog to digital converters are low power ADCs for reduced power consumption in the probe. Integrated circuits of thirty-two channels can be cascaded to produce 64-channel and 128-channel digital microbeamformers for an ultrasound array probe.

The present subject matter relates to techniques for single transducer harmonic motion imaging. The disclosed system can include a transducer. The transducer can be configured to generate an amplitude-modulated acoustic radiation force (AM-ARF) by sinusoidally modulating a duration of an excitation pulse of an acoustic radiation force, induce a harmonic motion on a target tissue using the AM-ARF, and simultaneously track the harmonic motion by collecting a tracking pulse. The tracking pulse can be interleaved between the excitation pulse.

An ultrasonic imaging system and an ultrasonic imaging method are provided. The ultrasonic imaging system includes a transmitting beamformer, a receiving beamformer, transducer elements and a controller unit. In a transmitting process, the controller circuit controls the transmitting beamformer to transmit ultrasonic sound signals. In a receiving process, echo signals are received at the transducer elements, the controller unit applies a common fine delay set to the echo signals by controlling a common fine delay beamformer of the receiving beamformer, the delayed echo signals are summed to generate first summation signals, the controller unit further applies compensated coarse delay sets to the first summation signals by controlling coarse delay beamformers of the receiving beamformer, and the delayed first summation signals are summed to generate output beam signals.