High-precision terahertz frequency modulated continuous wave imaging method using continuous wavelet transform

Abstract: Inspired by the extensive application of terahertz imaging technologies in the field of aerospace, we exploit a terahertz frequency modulated continuous wave imaging method with continuous wavelet transform algorithm to detect a multilayer heat shield made of special materials. This method uses the frequency modulation continuous wave system to catch the reflected terahertz signal and then processing the image data by the continuous wavelet transform with different basis functions. By calculating the sizes of the defects area in the final images and then comparing the results with real samples, a novel and practical high-precision terahertz imaging method are demonstrated. Our method can be an effective tool for the terahertz nondestructive testing of composites, drugs and some cultural heritages.