Abstract: Disclosed herein is a harmonic quadrature demodulation apparatus and method. The harmonic quadrature demodulation apparatus includes an input terminal for externally receiving an input focused signal, a harmonic phase estimation unit for estimating a second-order harmonic phase component from the input focused signal, and a harmonic detection unit for detecting a second-order harmonic component from the input focused signal. The second-order harmonic detection unit includes an in-phase component extractor, a quadrature component extractor, a Hilbert transformer, an adder and a low pass filter. The in-phase component extractor extracts an in-phase component of the input focused signal. The quadrature component extractor extracts a quadrature component of the input focused signal. The Hilbert transformer Hilbert-transforms a signal transmitted from the quadrature component extractor.

Abstract: Disclosed herein is an apparatus and method for extracting a second harmonic signal. The apparatus removes a fundamental frequency signal from a reception signal and then extracting the second harmonic signal. A transmitter generates a transmission signal by modulating a reference signal, and then transmits the transmission signal. A receiver extracts the second harmonic components of the reception signal by demodulating the reception signal received after the transmission signal is reflected by an external media. The transmitter includes a reference signal input unit, a first phase modulation unit, a second phase modulation unit, and a transmission signal output unit. The receiver includes a reception signal input unit, a first output signal generation unit, a second output signal generation unit, and a signal output unit.

Abstract: A beamforming apparatus is provided for improving beamforming accuracy by employing fractional delay filters in an interpolation process and reducing hardware complexity by using post-filtering technique. The beamforming apparatus of the present invention includes a post-filtering means implemented with fractional delay filters that combines block data, on the respective channels, supposed to be fractionally delayed and obtains a delay value of fractional part from the combined data. The post-filtering means collects the block data of the channels assigned identical coefficients and performs a filtering process simultaneously.

Abstract: User interaction is provided for a medical imaging system. The user interacts with the display rather than programmed buttons. The context between the user input and the display, such as identifying user selection of a bottom edge of a displayed image, is determined. The imaging system is controlled based on the context, such as altering the depth of imaging as the user drags the selected bottom edge up or down on the screen.

Abstract: Dynamic focusing is performed at Nyquist rate FN for the received signal. For each imaging point, a single-bit SDM sample is selected from each active array channel, according to the corresponding focusing delay. A block of data, centered at the selected SDM sample, is defined for each channel. Next, bit-wise block addition is performed to obtain the sum of all the blocks. The block addition output is fed to the demodulation filter. K(=?L/M?) demodulation filters are used. In another approach, the demodulation filters are placed just behind sigma-delta modulators. In each channel, K filters produce successively the demodulated signals for K consecutive imaging points. By taking the sum of samples retrieved from the same memory locations, dynamic focusing is achieved. Since each demodulation filter takes a single-bit SDM sequence as an input data, a simple accumulator calculates the sum of filter coefficients to be multiplied by input samples.

Abstract: The present invention discloses an ultrasound imaging system and method based on simultaneous multiple transmit-focusing using the weighted orthogonal chirp signals so that resolution of an ultrasound image is enhanced without sacrifice in the frame rate.

Abstract: A multiplierless single-bit dynamic focusing method is presented which can completely eliminate the demodulation error. In the proposed method, dynamic focusing is performed at the Nyquist rate, FN, for the received signal, meaning that the time interval between successive imaging points is the reciprocal of FN. For each imaging point, a single-bit SDM sample is selected from each active array channel, according to the corresponding focusing delay. Then, a block of data, centered at the selected SDM sample, is defined for each channel. Next, bit-wise block addition is performed to obtain the sum of all the blocks. Finally, the output of the block addition is fed to the demodulation filter. In consequence, if the block length is set equal to the demodulation filter length, the proposed method will produce the focused signal without any signal distortion.

Abstract: An ultrasound imaging system and method for making a harmonic image of a good SNR (signal-to-noise ratio) by effectively removing fundamental frequency components through a pulse-compressing using weighted chirp signals, is provided. The ultrasound imaging system includes: a transducer array for converting weighted chirp signals to ultrasound signals, and transmitting the ultrasound signals to a target object; a receiver for receiving signals reflected from the target object; a pulse-compressor for selectively pulse-compressing fundamental frequency components or harmonic frequency components in the reflected signals; and a producer for producing receive-focused signals from the pulse-compressed signals. Therefore, the ultrasound imaging system can form ultrasound image using the fundamental frequency components, and can form ultrasound harmonic image using the harmonic frequency components according to 2fo-correlation method or 2fo-correlation (PI) method.

Abstract: A three-dimensional (3D) ultrasound imaging system performs receive-focusing at voxels corresponding to pixels of a display device. The system comprises a display device; transducers for transmitting ultrasound signals toward the object and receiving echo signals from a voxel corresponding to a pixel on the display device, wherein the voxel is on a scanning region of the object; an RF volume memory for storing signals from the transducers; a signal processor for processing the stored signals to obtain 3D data sets with respect to the voxel; and an image former for forming the 3D image.

Abstract: Planar waves are transmitted to a target object with an angle of wave propagation corresponding to a center position of a receive subaperture. The echo signals reflected from the target object are received by the receive subaperture, stored in a receive pattern memory and dynamic-focused. The dynamic-focused signals are then combined to form at least one beam pattern to produce an ultrasound image.

Abstract: The present invention discloses an ultrasound imaging system and method which make a harmonic image of a good SNR (signal-to-noise ratio) by effectively removing fundamental frequency components through a pulse-compressing using the weighted chirp signals. The ultrasound imaging system includes: a transducer array for converting weighted chirp signals to ultrasound signals, and transmitting the ultrasound signals to a target object; a receiver for receiving signals reflected from the target object; a pulse-compressor for selectively pulse-compressing fundamental frequency components or harmonic frequency components in the reflected signals; and a producer for producing receive-focused signals from the pulse-compressed signals. Therefore, the ultrasound imaging system can form ultrasound image using the fundamental frequency components, and can form ultrasound harmonic image using the harmonic frequency components according to 2fo-correlation method or 2fo-correlation(PI) method.

Abstract: All RF data received by transducers in response to an ultrasonic signal that was transmit-focused on a point along a predetermined scan lines are stored to compute display data for those points of an object that do not necessarily correspond to the pixels of the screen of a display device. For the determination of display data for each pixel point, reflected ultrasonic signals from multiple points around the point of interest are found and used to detect the peak of a waveform constituted by the reflected ultrasonic signals. With this scheme, the distortion due to conventional interpolation used for a limited number of scan lines can be greatly reduced.

Abstract: An ultrasound imaging method forms an image of an object using signals reflected from the object after transmitting an ultrasound pulse to the object. In the method, at a first step, a predetermined first spread spectrum signal is converted to the ultrasound signal at one or more transducers and the ultrasound signal is transmitted to the object. At a second step, pulse compression is performed on a reflected signal of the ultrasound signal reflected from the object to form a pulse compressed signal. And the pulse compressed signal is processed to produce a receive-focused signal and the image of the object from the receive-focused signal is generated.

Abstract: Disclosed is a synthetic aperture focusing method for ultrasound imaging system based on planar waves. The planar waves are transmitted to a target object with an angle of wave propagation corresponding to a center position of a receive subaperture, and echo signals reflected from the target object are received by the receive subaperture, and the received echo signals are stored in a receive pattern memory, and the stored echo signals are dynamic-focused, and finally the dynamic-focused signals are combined to form at least one beam pattern.

Abstract: The present invention discloses an ultrasound imaging system and method which make a harmonic image of a good SNR(signal-to-noise ratio) by effectively removing fundamental frequency components through a pulse-compressing using the weighted chirp signals. The ultrasound imaging system includes: a transducer array for converting weighted chirp signals to ultrasound signals, and transmitting the ultrasound signals to a target object; a receiver for receiving signals reflected from the target object; a pulse-compressor for selectively pulse-compressing fundamental frequency components or harmonic frequency components in the reflected signals; and a producer for producing receive-focused signals from the pulse-compressed signals. Therefore, the ultrasound imaging system can form ultrasound image using the fundamental frequency components, and can form ultrasound harmonic image using the harmonic frequency components according to 2fo-correlation method or 2fo-correlation(PI) method.

Abstract: Ultrasound images are obtained using a set of Golay codes with orthogonal property as ultrasound receiving and transmitting signals. Ultrasound signals having a plurality of codes are transmitted simultaneously by using the orthogonal property of the Golay codes. A superior signal-to-noise rate (SNR) is realized using the Golay codes, without suffering a decrease in the frame rate.

Abstract: A storing method of a RF ultrasound pulse echo and a medical digital ultrasonic imaging apparatus capable of re-using the stored RF ultrasound pulse echo store and focus each RF ultrasound pulse echo received from a plurality of transducer elements in order to implement an ultrasonic image of at least one frame. Then, the stored RF ultrasound pulse echoes are analyzed, to thereby control the system according to the analysis result, which results in implementation of an optimal ultrasonic image.

Abstract: A three-dimensional (3D) ultrasound imaging system performs receive-focusing at voxels corresponding to pixels of a display device. The system comprises a display device; transducers for transmitting ultrasound signals toward the object and receiving echo signals from a voxel corresponding to a pixel on the display device, wherein the voxel is on a scanning region of the object; an RF volume memory for storing signals from the transducers; a signal processor for processing the stored signals to obtain 3D data sets with respect to the voxel; and an image former for forming the 3D image.

Abstract: Ultrasound images are obtained using a set of Golay codes with orthogonal property as ultrasound receiving and transmitting signals. Ultrasound signals having a plurality of codes are transmitted simultaneously by using the orthogonal property of the Golay codes. A superior signal-to-noise rate (SNR) is realized using the Golay codes, without suffering a decrease in the frame rate.

Abstract: An ultrasound imaging method for forming an image of an object using received signals reflected from the object, received after transmitting an ultrasound pulse to the object.