Design and Implementation of Analog-Digital Hybrid Beamformers for Low-Complexity Ultrasound Systems: A Feasibility...

Area of Science:

• Medical Imaging
• Ultrasound Technology
• Signal Processing

Background:

• Low-complexity ultrasound systems are crucial for wearable and 3-D imaging but face tradeoffs in spatial resolution and contrast.
• Existing analog and digital beamforming methods present limitations in achieving both high performance and system efficiency.

Purpose of the Study:

• To develop an efficient ultrasound system by mitigating the tradeoff between system complexity and imaging performance.
• To introduce and validate a novel analog-digital hybrid beamforming approach for ultrasound imaging.

Main Methods:

• A two-stage hybrid beamforming strategy was implemented: analog M-to-N beamforming followed by digital N-to-1 beamforming.
• The system was systematically designed using only four major integrated circuits, enabling full 64-channel transmission and reception.
• A customized 64-channel 1-D phased array was utilized for system demonstration with a tissue-mimicking phantom.

Main Results:

• Quantitative evaluation of signal-to-noise ratio, contrast-to-noise ratio, and full beam width at half maximum was performed.
• The hybrid beamforming system demonstrated effective performance in phantom imaging.
• The system successfully drove full 64-channel transmission and reception with minimal integrated circuits.

Conclusions:

• Analog-digital hybrid beamforming offers a viable solution to enhance ultrasound imaging capabilities in low-complexity systems.
• This approach is applicable to various array types, supporting sophisticated 3-D imaging and miniaturized wearable ultrasound devices.
• The developed system proves the efficacy of hybrid beamforming for advanced ultrasound applications.