The intermodulation distortion and envelope domain characterization technology are very important concepts of LSNA technology.

而互调失真表征技术和包络域表征技术是其中非常重要的概念。

youdao

A frequency domain characterization method using low frequency ultrasound is put forward to estimate parameters of ultra thin elastic layers, such as: the sound velocity, thickness and density.

本文提出一种定量无损估计超薄弹性层声速、厚度和密度参数的低频超声波频域定征方法。

youdao