Abstract: Methods and systems are provided for adapting signals from an ultrasound transducer for an ultrasound system. Where the signal processing in a transducer assembly outputs data incompatible with the ultrasound system, circuitry provided within the transducer assembly converts the data to be compatible with the ultrasound systems. For example, sub-array mixing is provided to partially beamform signals from a plurality of transducer elements. The resulting output signals from a plurality sub-arrays are provided through a cable to a connector housing of the transducer probe assembly. Since the mixers alter the data, such as shifting the data to an intermediate frequency, the output data may be at a frequency different than the frequencies for operation of the receive beamformer. Additional mixers are then provided to convert the intermediate frequency signals to radio frequency signals that may be processed by the ultrasound systems received beamformer.

Abstract: Methods, systems and probes communicate signals from a transducer for imaging or connection with an imaging system. Beamforming-related electronics are positioned in the connector housing of the transducer probe assembly. For example, analog-to-digital converters are positioned in the connector housing. Power is provided through connection with the ultrasound imaging system. Fans or other heat-dissipating structures are also positioned within the connector housing. Other beamformer electronics, such as delays and sums, are positioned in the imaging system, partly in the connector housing or entirely in the connector housing. Since the analog-to-digital converters are provided in the connector housing, partial digital beam forming may be provided in the transducer probe assembly. The length of the transducer cables is held constant to avoid interference and transmission line effects due to line-length variation.

Abstract: A plurality of application specific integrated circuit (ASIC) chips with different functions is provided. Each of the ASICs performs one or more functions along an ultrasound data path. The chips include communications protocols or processes for allowing scaling. For example, ASICs for backend processing include data exchange ports for communicating between other ASICs of the same type. As another example, receive beamformer ASICs cascade for beamformation. By providing ASICs implementing many or most of the ultrasound data path functions, with scalability, the same ASICs may be used for different system designs. A family of systems from high end to low-end using the same types of ASICs, but in different configurations, is provided.

Abstract: Element mapping and transmission of continuous waves are provided ultrasound imaging. For use with multiple dimensional or large arrays, the number of receive beamformer channels or associated cables connecting the transducer array to the receive beamformer may be limited. Subarrays of signals from different elements associated with similar phasing are combined without switching. The combined subarray signals are then received beamformed to generate a continuous wave image. Receive channels without clocking or beamforming prior to a steered continuous wave Doppler beamformer maximize dynamic range and reduce the power consumption. For further or different optimization of steering continuous waves, low voltage transmitters separate from high voltage transmitters are provided for a plurality of elements.

Abstract: Unipolar, bipolar or sinusoidal transmitters may leave the transmitter in any of various states at the end of one pulse. Undesired acoustic energy may be generated to change states prior to beginning another transmit sequence or pulse. For example, phase inversion for tissue harmonic imaging is performed where two sequential pulses are transmitted with different phases. The first waveform starts at a low state and ends at the low state of a unipolar transmitter. The next waveform starts at the high state. Transmit apodization or spectrum control techniques may require a pattern of waveform starting states different than a current state. Acoustic disruption due to a change of state of the transmitter between transmissions for imaging is minimized.

Abstract: Elements within each of a plurality of sub-arrays are dynamically grouped as a function of the steering direction. The dynamic grouping allows for partial beamforming with more similar delays within each grouping of elements within the sub-array. A plurality of partial beamformers is provided for each sub-array. Different ones of the elements are mapped to different ones of the partial beamformers as a function of the steering direction. As used herein, steering direction includes one or more of a focal location, a scan line angle, a scan line origin or other beamforming parameters associated with establishing a relative delay between elements. The shape or grouping of elements is changed at the beginning of any acquisition cycle, such as the beginning of transmit and receive operation for a given steering direction. Dynamic sub-array mapping may minimize negative effects of sub-array partial beamforming by providing an optimal shape of the sub-array groupings based on the steering direction.

Abstract: Medical diagnostic ultrasound stereo imaging is provided. A medical diagnostic ultrasound system operable to scan a body with ultrasound is also operable to generate a three dimensional stereoscopic view of the body. The video processing unit and/or display device create the stereoscopic display.

Abstract: A plurality of application specific integrated circuit (ASIC) chips with different functions is provided. Each of the ASICs performs one or more functions along an ultrasound data path. The chips include communications protocols or processes for allowing scaling. For example, ASICs for backend processing include data exchange ports for communicating between other ASICs of the same type. As another example, receive beamformer ASICs cascade for beamformation. By providing ASICs implementing many or most of the ultrasound data path functions, with scalability, the same ASICs may be used for different system designs. A family of systems from high end to low-end using the same types of ASICs, but in different configurations, is provided.

Abstract: Spatial derivatives are computed. In one method, gradients are determined from data in an acoustic domain rather than a Cartesian or display coordinate domain. The gradients determined from data in the acoustic domain are then transformed to the Cartesian coordinate or display screen domain. For example, a matrix function representing the spatial relationship between the acoustic domain and the Cartesian coordinate domain transforms the coordinates. As a result, spatial gradients in the Cartesian system are provided where acoustic domain data is being processed. In another method for volume rendering or three-dimensional imaging, a gradient is calculated from data in the display or screen domain. Data from a reconstructed 3D Cartesian coordinate grid or data in an acoustic domain is resampled to ray lines. The ray lines correspond to the display domain as compared to an arbitrary Cartesian coordinate format. The gradients are calculated from the resampled data in the screen domain.

Abstract: Transmitters for generating multilevel transmit waveforms for medical diagnostic ultrasound are provided. Voltages from a plurality of sources are superposed or summed. Switches control the amplitude and polarity of the summed voltages so that a transmit waveform having four or more, such as nine, voltage levels is provided. A simple switching pulser without a power amplifier combines voltages applied to two or more flux paths in a third flux path. Superposition of magnetic flux in the third flux path provides for an output voltage responsive to the sum and difference of two different voltages. Alternatively or additionally, the secondary windings of multiple transformers are connected in series with a transducer element. By providing different input voltages to each of the transformers, the multilevel transmit waveform is generated.

Abstract: Methods and systems for receiving different types of signal formats from different ultrasound transducers are provided. A base unit of an ultrasound system includes a connector and receiver circuit for connecting with one of multiple different types of transducers. For example, a conventional transducer providing analog information associated with a single element on one receive channel is connected with the connector and receiver circuit. Alternatively, a transducer outputting time division multiplex or other multiplex information representing multiple transducer elements is connected with the connector and receiver circuit. The receiver circuit processes the received information differently depending on the data format. For example, the preamplifier impedance or gain is different for single element signals versus time division multiplex signals. As another example, a low pass filter bandwidth is larger for time division multiplex signals than for signals representing a single element.

Abstract: Methods and systems for isolating transmit and receive circuitry at an ultrasound transducer element are provided. Separate electrodes or electrodes on opposite sides of a transducer element are connected to the separate transmit and receive paths or channels. Instead of high voltage transmit and receive switching, the transducer element isolates the transmit channel from the receive channel. The transmit channel includes circuitry for limiting the voltage at one electrode during receive processing, such as a switch operable to connect the electrode to ground. The receive channel includes circuitry for limiting the voltage at an electrode during transmit processing, such as a diode clamp preventing voltage swings greater than diode voltage at the electrode. Limiting the voltage provides virtual grounding or a direct current for either of the transmit or receive operation.

Abstract: A method and system for controlling bias voltage for use with an electrostatic transducer are provided. The bias voltage is dynamically varied or set as a function of imaging mode, depth gain compensation, elevational apodization, azimuthal apodization, timing with respect to the transmit waveform, center frequency of transmit and receive waves and desired modulation. Opposite polarity on sub-elements is also provided for removing signals from electromagnetic interference and crosstalk between elements.

Abstract: A segmented ultrasound system is provided. Ultrasound data, such as image data in a video format, is wirelessly transmitted to a multi-use display device from a handheld ultrasound device. Any of various multi-use display devices may be used, such as personal digital assistants (PDA), tablet computers, lap top computers, or personal computers.

Abstract: An image processing system according to an implementation of the invention includes a plurality of signal processing modules (210, 212, 214, 216, 218, 220, 222, 224, 226) inline in a data stream receiving signals. The signal processing modules include input multiplexers (234a-234i) adapted to control an order of or bypassing of processing by the signal processing modules. The signal processing modules may be implemented as hardware-based, nonlinear signal processing modules, such as log compress, decimation, compounding, blending, edge enhancement, automatic gain control, BHNS, lateral, or persistence filters.

Abstract: Methods and systems for electronically scanning within a three dimensional volume while minimizing the number of system channels and associated cables connecting a two-dimensional array of elements to an ultrasound system are provided. An array of semiconductor or micro-machined switches electronically interconnect various elements of the two-dimensional array. Elements associated with a substantially same time delay are connected together as a macro element, reducing the number of independent elements to be connected to beamforming or system channels. To beam form in the desired direction, the macro elements are configured as a phased array or along substantially straight lines in at least two dimensions (i.e. along the face of the two-dimensional transducer). Such macro elements allow transmission and reception along beams that are at an angle other than normal to the two-dimensional transducer array.

Abstract: Methods and systems for receiving different types of signal formats from different ultrasound transducers are provided. A base unit of an ultrasound system includes a connector and receiver circuit for connecting with one of multiple different types of transducers. For example, a conventional transducer providing analog information associated with a single element on one receive channel is connected with the connector and receiver circuit. Alternatively, a transducer outputting time division multiplex or other multiplex information representing multiple transducer elements is connected with the connector and receiver circuit. The receiver circuit processes the received information differently depending on the data format. For example, the preamplifier impedance or gain is different for single element signals versus time division multiplex signals. As another example, a low pass filter bandwidth is larger for time division multiplex signals than for signals representing a single element.

Abstract: Transmitters for generating multilevel transmit waveforms for medical diagnostic ultrasound are provided. Voltages from a plurality of sources are superposed or summed. Switches control the amplitude and polarity of the summed voltages so that a transmit waveform having four or more, such as nine, voltage levels is provided. A simple switching pulser without a power amplifier combines voltages applied to two or more flux paths in a third flux path. Superposition of magnetic flux in the third flux path provides for an output voltage responsive to the sum and difference of two different voltages. Alternatively or additionally, the secondary windings of multiple transformers are connected in series with a transducer element. By providing different input voltages to each of the transformers, the multilevel transmit waveform is generated.

Abstract: A segmented ultrasound system is provided. Ultrasound data, such as image data in a video format, is wirelessly transmitted to a multi-use display device from a handheld ultrasound device. Any of various multi-use display devices may be used, such as personal digital assistants (PDA), tablet computers, lap top computers, or personal computers.

Abstract: A method and system for controlling bias voltage for use with an electrostatic transducer are provided. The bias voltage is dynamically varied or set as a function of imaging mode, depth gain compensation, elevational apodization, azimuthal apodization, timing with respect to the transmit waveform, center frequency of transmit and receive waves and desired modulation. Opposite polarity on sub-elements is also provided for removing signals from electromagnetic interference and crosstalk between elements.