为解决超声相控阵汽车发动机腐蚀检测系统中全通道采集带来的存储传输数据量大的问题,进行压缩传感理论在超声相控阵发动机检测系统中的应用研究。根据超声相控阵成像的方式,首先对单阵元接收到的回波信号进行压缩传感:对回波信号在稀疏变换域中的稀疏度进行分析,并应用随机高斯矩阵进行测量采样,正交匹配追踪算法进行信号重构;然后依据超声相控阵的成像原理,对腐蚀缺陷进行压缩传感下的B扫描成像;最后分析结果表明,压缩传感下的缺陷图像具有较高的重构精度,此研究为降低超声相控阵发动机缸体检测系统复杂度以及数据采样传输对硬件的要求提供了新的思路。
To solve the problem of large amount of storage and transmission data brought by the characteristic that sampling in all channels in the ultrasonic phased array detection system for engine cylinder, the research on the ap- plication of compressive sensing theory in the corrosion inspection of the engine cylinder is carried out. According to the imaging approach of the ultrasonic phased array, firstly, we apply the compressive sensing theory to the single element echo signal and the work of this part includes that analyze the sparse degrees of the echo signals in the sparse transform domains, sample the signals using the Gaussian random matrix and reconstruct them by the orthog- onal matching pursuit algorithm. Then, according to the imaging principle of the ultrasonic phased array, the B- scan images of the corrosion defects are obtained by using the compressive sensing theory. Finally, the results show that the corrosion defect images reconstructed using the compressive sensing theory have high precision, and our research proposes a new thinking for reducing the complexity of engine cylinder testing system and the demand of the hardware.