An apparatus and method for frequency tuning/tracking between an electrical subsystem and a mechanical transducer subsystem is presented. An electromechanical transducer generates acoustic pulses as it is driven by a transmit signal from an electrical subsystem. As the transmit signal goes inactive, the settling behavior of the transducer is registered from which the difference in frequency between the resonance of the electromechanical transducer and the transmit signal frequency is determined and utilized for locking the electrical subsystem to the mechanical transducer subsystem by either tuning operating frequency of the electrical subsystem, or the mechanical transducer, to keep them matched (locked).

A method of signal processing for suppressing at least one sidelobe of an autocorrelation function between a received code sequence and a mismatched filter coefficient vector comprises: setting a filter coefficient vector; modifying the filter coefficient vector, thus generating a modified filter coefficient vector; correlating the modified filter coefficient vector with the code sequence yielding an autocorrelation function comprising a main peak and sidelobes; generating a performance parameter that describes the sidelobe suppression of the autocorrelation function; setting the modified filter coefficient vector as the new filter coefficient vector for a subsequent iteration if the performance parameter shows a performance improvement; and discarding the modified filter coefficient vector if the performance parameter shows no performance improvement.

A hybrid pulse compression RF system is provided herein in which an enhanced noise waveform and a hybrid waveform are generated to detect a target. For example, the system includes a signal generator that generates an LFM waveform and an enhanced waveform in sequence such that a transmitter of the system transmits the waveforms in the generated sequence in a direction of a possible target. The enhanced waveform may be a partially randomized version of the LFM waveform. If a target is present, the waveforms reflect off the target and are captured by the system in the sequence in which the originally generated waveforms are transmitted. Once captured, the reflected waveforms are processed by the system to generate a hybrid waveform for display such that the range and Doppler resolution and detection capabilities are significantly superior to the state of the art LFM or noise waveform RF systems.

A Multiple Aperture Ultrasound Imaging system and methods of use are provided with any number of features. In some embodiments, a multi-aperture ultrasound imaging system is configured to transmit and receive ultrasound energy to and from separate physical ultrasound apertures. In some embodiments, a transmit aperture of a multi-aperture ultrasound imaging system is configured to transmit an omni-directional unfocused ultrasound waveform approximating a first point source through a target region. In some embodiments, the ultrasound energy is received with a single receiving aperture. In other embodiments, the ultrasound energy is received with multiple receiving apertures. Algorithms are described that can combine echoes received by one or more receiving apertures to form high resolution ultrasound images. Additional algorithms can solve for variations in tissue speed of sound, thus allowing the ultrasound system to be used virtually anywhere in or on the body.

The invention relates to a method for the optimization of the process decoding coded ultrasound signals. The method according to the invention provides the following steps: defining/selecting a coding function for ultrasound pulses transmitted to a body under examination by means of a predetermined probe; defining the coefficients of a filter decoding the received signal depending on the selected coding function; using said filter coefficients as the setting of the decoding filter corresponding to said predetermined probe for all the ultrasound systems provided in combination with said probe; and wherein the coefficients of the decoding filters are determined by the minimization, by a heuristic iterative process, of the difference between the characteristics of a receive signal, obtained in a real transmit/receive sequence and filtered with a decoding filter, and the characteristics of an ideal receive signal, that is a nominal one, by using as the coefficients of the decoding filter those obtained in the last iterative step.

The present invention related to an ultrasound imaging system win which the scan head includes a beamformer circuit that performs far field subarray beamforming or includes a sparse array selecting circuit that actuates selected elements. When using a hierarchical two-stage or three-stage beamforming system, three dimensional ultrasound images can be generated in real-time. The invention further relates to flexible printed circuit boards in the probe head. The invention furthermore related to the use of coded or spread spectrum signaling in ultrasound imagining systems. Matched filters based on pulse compression using Golay code pairs improve the signal-to-noise ratio thus enabling third harmonic imaging with suppressed sidelobes. The system is suitable for 3D full volume cardiac imaging.

The present invention relates to an ultrasound imaging system in which the scan head either includes a beamformer circuit that performs far field subarray beamforming or includes a sparse array selecting circuit that actuates selected elements. When used with second stage beamforming system, three dimensional ultrasound images can be generated.

A hybrid pulse compression RF system is provided herein in which an enhanced noise waveform and a hybrid waveform are generated to detect a target. For example, the system includes a signal generator that generates an LFM waveform and an enhanced waveform in sequence such that a transmitter of the system transmits the waveforms in the generated sequence in a direction of a possible target. The enhanced waveform may be a partially randomized version of the LFM waveform. If a target is present, the waveforms reflect off the target and are captured by the system in the sequence in which the originally generated waveforms are transmitted. Once captured, the reflected waveforms are processed by the system to generate a hybrid waveform for display such that the range and Doppler resolution and detection capabilities are significantly superior to the state of the art LFM or noise waveform RF systems.

An ultrasound signal processing device includes ultrasound signal processing circuitry that operates as: a transmitter that causes an ultrasound probe to transmit ultrasound beams to an ultrasound main irradiation area defined by two straight lines each connecting a focal point and a different end of a transmission transducer element array; a receiver that generates receive signal sequences; a delay-and-sum calculator that sets first and second target areas in the ultrasound main irradiation area, and performs delay-and-summing of receive signal sequences based on ultrasound reflection from measurement points in the first and second target areas thereby to generate sub-frame acoustic line signals, the first target area is an entirety of an area located at or shallower than a focal depth, the second target area is part of an area located deeper than the focal depth; and a synthesizer that synthesizes sub-frame acoustic line signals to generate a frame acoustic line signal.

A Multiple Aperture Ultrasound Imaging system and methods of use are provided with any number of features. In some embodiments, a multi-aperture ultrasound imaging system is configured to transmit and receive ultrasound energy to and from separate physical ultrasound apertures. In some embodiments, a transmit aperture of a multi-aperture ultrasound imaging system is configured to transmit an omni-directional unfocused ultrasound waveform approximating a first point source through a target region. In some embodiments, the ultrasound energy is received with a single receiving aperture. In other embodiments, the ultrasound energy is received with multiple receiving apertures. Algorithms are described that can combine echoes received by one or more receiving apertures to form high resolution ultrasound images. Additional algorithms can solve for variations in tissue speed of sound, thus allowing the ultrasound system to be used virtually anywhere in or on the body.