The use of power-efficient transmitters to establish acoustic wave energy having low undesirable harmonics is achieved by adjusting the transmitter output waveform to minimize the undesirable harmonics. In one embodiment, both the timing and slope of the waveform edges are adjusted to produce the desired output waveform having little or no second harmonics. In the embodiment, output waveform timing adjustments on the order of fractions of the system clock interval are provided. This then allows for very fine control of a coarsely produced waveform. In one embodiment, the user can select the fine tuning to match the transmitter output signal to a particular load transducer.

An apparatus for processing a medical image includes: a receiver configured to receive a signal having a plurality of frequency bands; an image reconstructor configured to segment the signal into a first signal of a first frequency band and a second signal of a second frequency band based on a signal strength, and configured to generate a first reconstructed image of the first frequency band and a second reconstructed image of the second frequency band; and an image synthesizer configured to synthesize the first reconstructed image and the second reconstructed image.

An ultrasonic diagnostic apparatus that transmits/receives an ultrasonic wave to/from a subject using an ultrasonic probe and generates an image includes: a transmission unit that converts a pulsed transmission signal including a fundamental wave component into a transmission ultrasonic wave and transmits the transmission ultrasonic wave to the inside of the subject; a receiving unit that generates a reception signal based on a reflected ultrasonic wave from the subject; a separation unit that separates the reception signal into first and second components; a phase control unit that generates a third component by controlling a phase of the second component such that a time at which amplitude is maximized is the same between the first and second components; a combining unit that combines the first and third components to generate a composite reception signal; and an image generation unit that generates an image based on the composite reception signal.

Provided is a technique that implements harmonic imaging in an ultrasound diagnostic apparatus, being unaffected by the voltage-dependent distortion and nonlinear characteristics of the transmit system in the ultrasound diagnostic apparatus that incorporates the transmit amplifier, the ultrasound probe, and the like, facilitating adjustment of the transmit voltage, and achieving a frame rate substantially equivalent to that of the conventional PI method. In the amplitude modulation method that synthesizes the transmit acoustic fields, thereby eliminating a basic wave component of an acoustic wave and creating an image from nonlinear component echoes being extracted, one transmit and receive out of plural transmits and receptions to obtain one scanning line also serves as the transmit and receive for obtaining other scanning line. The echo signals obtained by the shared transmit and receive are used to form the receive beams respectively on both the scanning lines that share the transmit and receive.

Systems and methods for filtering an analog waveform before it is sampled by an analog-to-digital converter (ADC) in an ultrasound system are provided. The waveform can be filtered by delaying the same waveform by two different time delays and combining the delayed waveforms to effectively cancel out the fundamental components, thereby providing more sensitive detection of harmonic components in received echo signals. This filtering approach leverages an architecture that can also be used for multiline beamforming to perform the temporal filtering, in which a single acoustic signal can be read out of the ARAM twice, separated by time, taking advantage of the fact that the ARAM allows for non-destructive read operations.

An image generation apparatus including a computation processing section that generates an ultrasonic image from a received signal associated with each scanning of an object in which an ultrasonic wave is transmitted and received is provided. The computation processing section sets, for each scanning, a selection range over which the received signal is received and which includes the direction of the scanning, calculates weights used in a beamforming process based on the received signals within the selection range, and carries out the beamforming process based on the weights to generate an image associated with the scanning.

1.sup.st and 2.sup.nd pulsed waves (103, 104) with 1.sup.st and 2.sup.nd center frequencies are transmitted along 1.sup.st and 2.sup.nd transmit beams so that the 1.sup.st and 2.sup.nd pulsed waves overlap at least in an overlap region (Z) to produce nonlinear interaction scattering sources in said region. The scattered signal components from at least the nonlinear interaction scattering sources are picked up by a receiver (102) and processed to suppress other components than said nonlinear interaction scattered signal components, to provide nonlinear interaction measurement or image signals. At least a receive beam is scanned in an azimuth or combined azimuth and elevation direction to produce 2D or 3D images of said nonlinear interaction scattering sources.

A measurement and imaging instrument capable of beamforming with high speed and high accuracy without approximate calculation. The instrument includes a reception unit which receives a wave arriving from a measurement object to generate a reception signal; and an instrument main body which performs a lateral modulation while superposing two waves in a two-dimensional case and three or four waves in a three-dimensional case in beamforming processing of the reception signal in which at least one wave arriving from the measurement object is processed as being transmitted or received in the axial direction or directions symmetric with respect to the axial direction to generate a multi-dimensional reception signal, performs Hilbert transform with respect to the multi-dimensional reception signal, and performs partial derivative processing or one-dimensional Fourier transform to generate analytic signals of the multi-dimensional reception signals of the two waves or the three or four waves.

Nonlinear ultrasound imaging systems and methods are disclose. In one aspect, a nonlinear ultrasound imaging system includes a first transducer configured to transmit a first ultrasound signal along a scan line, a second transducer configured to sweep a second ultrasound signal along the scan line such that the first and second ultrasound signals intersect at a plurality of voxels, and a third transducer configured to receive echoes associated with interactions of the first and second ultrasound signals at the plurality of voxels. The nonlinear ultrasound imaging system further includes a processor configured to generate an ultrasound image based on the echoes.

A multi-user system to simultaneously perform operations such as communication, RADAR, Light Detection and Ranging (LIDAR) and Relative Navigation (RELNAV). The techniques according to an embodiment includes generating a Fourier based orthogonal chirp sequence of length P, a prime number greater than the number of users targeted for communication. The orthogonal chirp sequence is based on an identifier, in the range of one to P−1, associated with one of the targeted users. The method further includes using the orthogonal chirp sequence to generate a spread user signal based on a message directed to the one targeted users. The method further includes generating a sequence of training pulses for insertion into the spread user signal to facilitate reception of the signal. The method further includes transmitting and receiving a reflection of the spread user signal from one of the targeted users, the reflection used to detect and range the user.