Design and implementation of an advanced high-speed data acquisition system for photoacoustic tomography

Photoacoustic Tomography (PAT) combines the advantages of optical imaging and ultrasound imaging, playing an indispensable role in biomedical research and clinical investigations. However, current advanced PAT systems are large in size and expensive, limiting their widespread adoption. Despite attempts to reduce costs by using low-cost light sources, research on sensor driving and data acquisition optimization remains lacking. Therefore, we present a low-cost and high-speed PAT system consisting of a 20Hz pulse frequency PhotoSonus-YAG laser, ultrasound array transducer, a multi-channel high-speed data acquisition system, and computer.This study designs a multi-channel high-speed data acquisition system (DAS) based on FPGA. The system, with FPGA as the core, DDR III SDRAM as the storage device, and a 14-bit high-performance ADC as the core analogto- digital conversion chip, utilizes a USB-based high-speed data acquisition card solution. To meet the demand for synchronous processing of multi-channel signals, the system employs high-end FPGA chips from Xilinx’s ZYNQ7000 series and Texas Instruments’ AFE5816 chips from the ultrasonic AFE series. These components are interconnected via Low Voltage Differential Signaling (LVDS) interfaces to ensure high-speed and highly reliable digital signal transmission. The designed high-speed data acquisition system achieves a collection of 65MSPS × 14 Bit × 16 channels, with a maximum data acquisition speed of 1000 frames per second. This design not only significantly reduces the volume and cost of the PAT system but also ensures the quality of image preservation through real-time data acquisition and processing.