Grating lobes suppression by adding virtual receiving subaperture in synthetic aperture imaging

Area of Science:

• Ultrasound imaging
• Signal processing
• Medical imaging technology

Background:

• Grating lobes are artifacts in synthetic aperture imaging that degrade image quality.
• Suppression of grating lobes is crucial for accurate visualization and diagnosis.

Purpose of the Study:

• To introduce and validate a new method for suppressing grating lobes using a Virtual Receiving Subaperture (VRS).
• To analyze the impact of VRS on the impulse response and signal-to-noise ratio (SNR) of imaging systems.

Main Methods:

• Creation of a Virtual Receiving Subaperture (VRS) by synthesizing virtual transducer elements.
• Analytical modeling of the synthetic aperture imaging system's impulse response with VRS.
• Numerical calculations and experimental validation using generalized Plane Wave Imaging and synthetic transmit aperture (STA) imaging.

Main Results:

• The VRS method significantly reduces grating lobe amplitude, comparable to halving the receiving aperture pitch.
• Numerical simulations show a doubling of the signal-to-noise ratio (SNR).
• Experimental results demonstrate improved visualization of objects and a 15dB reduction in grating lobes for superficial cyst imaging.

Conclusions:

• The Virtual Receiving Subaperture (VRS) method is an effective technique for grating lobe suppression in synthetic aperture imaging.
• VRS enhances image quality, contrast, and the ability to visualize structures previously not visible or poorly contrasted.
• The method offers significant improvements for applications like superficial cyst imaging.