超声检测系统设计及回波信号特征分析

文物的无损检测对其保护有着重大的意义，可为后续的加固和保护提供有力的依据。针对传统超声检测设备增益小，回波信号特征少，难以满足石木质文物缺陷检测的缺点，设计了一种基于FPGA作为主控制器的石质木质材料超声无损检测系统，并对回波信号特征进行了详细分析。该系统硬件部分包括超声信号的激励，回波信号的放大、滤波和采样模块的设计；软件部分包括FPGA的逻辑设计和USB通信的软件设计。同时将获取到的回波信号进行了特征分析，包括时域分析、频域分析和小波分析，得到了回波信号的特征，为石质木质材料的超声无损检测奠定了基础。

Design of ultrasonic testing system and analysis of echo signal characteristics

The non-destructive testing of cultural relics has great significance for the protection of cultural relics and can provide a strong basis for subsequent reinforcement and protection. In view of the shortcomings of the traditional ultrasonic testing equipment with small gain and low echo signal characteristics, it is difficult to meet the defect detection of stone or wooden relics. An ultrasonic nondestructive testing system for stone or wood materials based on FPGA as the main controller is designed, and the characteristics of echo signal are analyzed in detail. The hardware part of the system includes the excitation of ultrasonic signal, the amplification of the echo signal, the design of the filter and sampling module. The software part includes the logic design of FPGA and the software design of the USB communication. At the same time, the acquired echo signal is analyzed, including the time domain analysis, frequency domain analysis and wavelet analysis, and the characteristics of the echo signal are obtained, which lays the foundation for the ultrasonic nondestructive testing of the stone wood materials.