Kirkpatrick James P, Wilcox Paul D, Smith Robert A
IEEE Trans Ultrason Ferroelectr Freq Control. 2019 Apr 3. doi: 10.1109/TUFFC.2019.2909138.
Row-column Addressed (RCA) arrays are 2-d arrays formed by two orthogonal overlapping linear arrays made up of elongated elements. This substantially reduces the number of elements in the 2-d array. Modelled data are used to compare RCA arrays in pulse-echo mode to fully populated 2-d arrays for Non-destructive Evaluation (NDE) applications and an improved beamforming algorithm based on the total focusing method is tested. Improved beamforming has led to a less than half-wavelength diameter conical bottom hole being successfully detected experimentally using an RCA array, with a maximum signal-to-noise ratio of 17:0dB (3.s.f). The average difference between the -6dB drop width and the nominal drill bit diameter when sizing flat bottom holes experimentally using RCA arrays is also improved compared to plane B-scan algorithms from (1:29 ± 0:07)mm to (0:23 ± 0:04)mm. These developments demonstrate the advantages of using RCA arrays over conventional fully populated 2-d arrays and provides a basis for their use, and development, in the field of NDE.
行列寻址（RCA）阵列是由两个正交重叠的线性阵列组成的二维阵列，这些线性阵列由细长元件构成。这大大减少了二维阵列中的元件数量。使用建模数据在脉冲回波模式下将RCA阵列与用于无损检测（NDE）应用的全填充二维阵列进行比较，并测试了一种基于全聚焦方法的改进波束形成算法。改进的波束形成使得使用RCA阵列通过实验成功检测到直径小于半波长的锥形平底孔，最大信噪比为17.0dB（3位有效数字）。与平面B扫描算法相比，使用RCA阵列对平底孔进行实验测量时，-6dB下降宽度与标称钻头直径之间的平均差值也从（1.29±0.07）mm提高到了（0.23±0.04）mm。这些进展证明了使用RCA阵列优于传统的全填充二维阵列，并为其在无损检测领域的应用和发展提供了基础。
