Sigma-delta receive beamformer based on cascaded reconstruction for ultrasound imaging application.

A pre-delay reconstruction sigma-delta beamformer (SDBF) was recently proposed to achieve a higher level of integration in ultrasound imaging systems. Nevertheless, the high-order reconstruction filter used in each channel of SDBF makes the beamformer highly complex. The beamformer can be simplified by reconstructing the signal after the delay-and-sum process with only one filter.

New demodulation method for efficient phase-rotation-based beamforming.

In this paper, we present a new demodulation method to reduce hardware complexity in phase-rotation-based beamforming. Due to its low sensitivity to phase delay errors, quadrature demodulation, which consists of mixing and lowpass filtering, is commonly used in ultrasound machines. However, because it requires two lowpass filters for each channel to remove harmonics after mixing, the direct use of quadrature demodulation is computationally expensive.

Nonlinear diffusion in Laplacian pyramid domain for ultrasonic speckle reduction.

A new speckle reduction method, i.e., Laplacian pyramid-based nonlinear diffusion (LPND), is proposed for medical ultrasound imaging.

New demodulation filter in digital phase rotation beamforming.

In this paper, we present a new quadrature demodulation filter to reduce hardware complexity in digital phase rotation beamforming. Due to its low sensitivity to phase delay errors, digital quadrature demodulation is commonly used in ultrasound machines. However, since it requires two lowpass filters for each channel to remove harmonics, the direct use of conventional finite impulse response (FIR) filters in ultrasound machines is computationally expensive and burdensome.