微纳电子技术

电容式微机械超声换能器(CMUT)具有频带宽、成本低、易于与电路集成等优点,在超声环形阵列的构建中展现出独特优势,在医学成像领域有广泛的应用潜力。基于自主研制的一种CMUT环形阵列结构,设计并搭建了多通道超声成像系统。该系统设计了以现场可编程门阵列(FPGA)为主控的32通道超声收发板卡,采用PXIe高性能模块化设计,通过N张板卡实现32×N个通道的脉冲发射与超声回波采集,且支持最低几百k Hz至最高65 MHz的采样率,适配不同CMUT的中心频率。通过对亚克力圆柱体进行成像测试,表明系统具有良好的性能。该系统具有可扩展的模块化硬件结构与高度灵活的参数配置方案,为基于CMUT的多通道医学超声成像系统的实际应用提供了技术支撑。

A capacitive micromachined ultrasonic transducer(CMUT)offers advantages such as wide bandwidth,low cost,and easy integration with electronic circuits,demonstrating unique strengths in the construction of ultrasonic ring arrays.It holds significant potential for applications in medical imaging field.Based on a self-developed CMUT ring array structure,a multi-channel ultrasound imaging system was designed and implemented.This system features a 32-channel ultrasonic transceiver board controlled by a field-programmable gate array(FPGA)and adopts a high-performance modular design based on PXIe.By employing N units of the board,the system enables pulse transmission and ultrasonic echo acquisition for up to 32×N channels.It supports sampling rates ranging from a few hundred k Hz to a maximum of 65 MHz,accommodating different CMUT center frequencies.Imaging tests performed on an acrylic cylinder demonstrate the system's excellent performance.With a scalable modular hardware architecture and highly flexible parameter configuration,this system provides a technological foundation for the practical application of CMUT-based multi-channel medical ultrasound imaging systems.