Physical Defect Localizing Methodology for Coaxial Cable Based on Quadratic Propagation Coefficient Model

A physical defect localizing method based on a quadratic propagation coefficient model is proposed in this paper, which improves the localizing accuracy of the physical defects for coaxial cable. By analyzing the principle of frequency domain reflectometry (FDR) based fault localizing approaches, the factors affecting the positioning accuracy and spatial resolution of errors are found and classified into distributed parameter conditions. The quadratic propagation coefficient model is deduced by combining the distributed parameter conditions and the S-parameters. Based on it, the Integral Transform Method is improved to enhance the spatial resolution of the localization spectrum. Moreover, the effect of sweep points on localization results and the reason for the higher resolution of the proposed method is analyzed. Experiments demonstrated that the proposed method based on the quadratic propagation coefficient model could enhance the effectiveness of physical defect localization compared with existing methods.