Integrated Hybrid Sub-Aperture Beamforming and Time-Division Multiplexing for Massive Readout in Ultrasound Imaging

Area of Science:

• Ultrasound Imaging Systems
• Integrated Circuit Design
• Biomedical Engineering

Background:

• Traditional ultrasound systems face challenges with extensive receive signal interconnects.
• Massive interconnects increase system complexity, power consumption, and cost.
• Need for miniaturized and efficient front-end electronics in medical imaging.

Purpose of the Study:

• To demonstrate a hybrid sub-aperture beamforming (SAB) and time-division multiplexing (TDM) approach.
• To reduce the number of receive signal interconnects in ultrasound imaging.
• To develop and validate a single-chip front-end system prototype.

Main Methods:

• Fabrication of a single-chip prototype using 180-nm HV BCD technology.
• Integration of 5x1 SAB with 8x1 TDM for interconnect reduction.
• Implementation of on-chip high-voltage pulsers, T/R switch, VG-LNA, and analog delay-and-sum beamformer.
• Validation using electrical and acoustic measurements on a CMUT array for intracardiac echocardiography.

Main Results:

• Achieved a 40x reduction in receive signal interconnects.
• Demonstrated on-chip pulsers with up to 70 V output.
• SAB provided 32-step fine delays for beam steering up to 45 degrees.
• Prototype validated for intracardiac echocardiography applications.

Conclusions:

• Hybrid SAB with TDM is effective for massive interconnect reduction in ultrasound.
• The single-chip prototype demonstrates feasibility and high performance.
• This technology enables more compact and efficient ultrasound imaging systems.