Correlation-based correction of sound velocity inhomogeneities using delta-sigma modulators

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Signal Processing

Background:

• Delta-sigma (deltasigma) modulators offer reduced cost and complexity for ultrasonic imaging beamformers due to high sampling rates and single-bit data width.
• Previous research indicated that appropriate dynamic focusing can achieve comparable image quality to conventional methods with adequate signal-to-quantization noise ratio (SQNR).

Purpose of the Study:

• To investigate the application of delta-sigma modulator based beamformers for correlation-based phase aberration correction.
• To evaluate the performance of this approach compared to conventional radio frequency (rf) beamformers.
• To assess the impact of different dynamic focusing techniques on phase aberration correction.

Main Methods:

• Utilized delta-sigma modulator based beamformers for phase aberration correction.
• Employed correlation-based methods to address sound velocity inhomogeneities.
• Investigated various dynamic focusing strategies within the phase aberration correction framework.

Main Results:

• Achieved efficient implementation of phase aberration correction with performance comparable to conventional rf beamformers.
• Demonstrated a contrast improvement exceeding 6 dB.
• Confirmed that single-bit dynamic focusing does not compromise the overall performance of phase aberration correction.

Conclusions:

• Delta-sigma modulator based beamformers are effective for phase aberration correction in ultrasonic imaging.
• This method offers significant contrast improvement and comparable performance to traditional techniques.
• Single-bit dynamic focusing is a viable strategy within this system.