双缓存超声TOFD数据采集系统设计

针对数字式超声TOFD(超声衍射时差)无损检测系统对数据采集的高速、高精度要求,设计了一种基于FPGA和USB2.0的双缓存超声TOFD数据采集系统。该系统采用10-bit精度高速模数转换芯片AD9211,最高采样频率达120MH_z。使用LabVIEW编写上位机软件,实现波形的显示和存储,以及对采样频率、采样深度等的控制。本系统的双缓存设计不仅实现了高速数据的缓存,并且实现了上位机数据读取和A/D转换的同步,实验结果表明该系统能够满足数字式超声TOFD数据采集的需求。

Design of Dual-Cached Data Acquisition System for Ultrasonic TOFD

To meet the requirements of data acquisition for high speed and precision of digital ultrasonic TOFD (time of flight diffraction) nondestructive testing system,a dual-cached data acquisition system for ultrasonic TOFD based on FPGA and USB2.0 is designed.The high speed ADC chip AD9211 with the precision of 10-bit and maximum sampling rate of 120 MHz is adopted.The upper computer software is based on LabVIEW,which achieves display and adjustment of waveform,and controls sampling rate and sampling depth,etc.The design of dual-cache not only achieves the cache for high speed data,but also synchronizes the data reading of upper computer and A/D conversion.Experiment results validate that this system can meet the requirements of data acquisition of digital ultrasonic TOFD.