为探讨接收孔径对超声导波合成孔径阵列成像检测的影响机制，提出将接收矩阵作为分析工具对超声导波合成孔径阵列成像原理展开研究。针对板中超声水平剪切（Shear horizontal，SH）导波直线合成孔径阵列，运用波幅接收矩阵和渡越时间接收矩阵对接收孔径进行讨论，分析直线阵列信号所特有的圆锥曲线特征和合成孔径成像算法，重点就满秩接收孔径、半（满）秩接收孔径和单（位）秩接收孔径对超声导波合成孔径阵列成像检测的影响机理进行研究。研究结果显示，波幅接收矩阵和渡越时间接收矩阵具有相同的秩，与接收阵元数成正比关系，秩的大小决定阵列成像的信噪比，阵列图像信噪比随秩单调递增；半秩接收孔径图像与满秩接收孔径图像信噪比较为接近，单秩接收孔径图像的信噪最小，图像背景噪声最为强烈。成像试验验证了理论分析的合理性，表明接收矩阵是研究超声导波合成孔径阵列成像的有力工具，接收矩阵的秩是接收孔径对阵列成像检测的结决定性影响因素，论文研究工作可为深入开展超声导波非规则阵列成像检测研究与应用提供基础。
In order to explore the influence mechanism of receiving aperture on imaging and testing of synthetic aperture array for ultrasonic guided waves, the receiving matrix (RM) is proposed to discuss imaging theory of synthetic aperture array for ultrasonic guided waves. Taking the line synthetic aperture array of ultrasound SH (Shear horizontal) guided waves in plate as an object, the receiving aperture is discussed by using the receiving amplitude matrix (RAM) and the receiving flight-time matrix (RFTM), the conic characteristic of line array signals and the synthetic aperture imaging algorithm are analyzed, from which the influence mechanism of the full-rank receiving aperture (FRRA), the half-rank receiving aperture (HRRA) and the unit-rank receiving aperture (URRA) on imaging and testing of synthetic aperture array are emphasized especially. The research result shows that the RAM and the RFTM have the same rank, which rank is not only proportional to the number of receiving array elements, but also determines the image Signal-to-Noise ratio (SNR), and image SNR may be monotonically increasing with increasing of RM rank. However, the image SNR of HRRA is close to that of FRRA, the image SNR of URRA is the smallest and which image background noise is the strongest. The imaging experiment verify the validity of the theory analyzing proposed and indicate that the rank of RM is a key influencing factor on imaging and testing of synthetic aperture array, and the RM is a powerful tool for analyzing the influence mechanism of receiving aperture on imaging and testing, which would provides important foundation for further research and application of imaging and testing of irregular array for ultrasonic guided wave.
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