Reflectivity Calculation And Experimental Investigation Of Multilayer Absorbing Materials With Embedded Frequency Selective Surfaces

As the rapid development of high quality resolution and high reliability detect technology, it's a consensus of main country in the world that using stealth technology can enhance the weapon system's operational efficiency. The stealth technology's rising status promotes the absorbing materials'development, research and developing high quality absorbing materials has been an important issue in the military field. Reflectivity is an important parameter of absorbing materials, so it's significant to research the calculation of absorbing materials'reflectivity and direct the design and manufacture of absorbing materials. In this thesis, the theoretical and experimental investigation on composite absorbing materials with embedded frequency selective surface (FSS) will be carried on.This thesis focuses on the theoretical calculation and experimental analysis of composite absorbing materials with embedded FSS. By summarizing and analyzing the calculation of composite absorbing materials'reflectivity at home and abroad, we choose equivalent transmission line method. First, dispersion characteristic of FSS was investigated and simulated using Ansoft HFSS software. Then, the reflectivity calculation model of multilayer absorbing materials with embedded FSS was proposed. The expression of FSS susceptance and test method of FSS conductance was provided. By theoretic analysis, the influence rule of FSS size, including susceptance vs. frequency and susceptance vs. size were also presented. The impact of medium's electromagnetic parameters and the thickness of composite absorbing materials were obtained. After analyzing many experiment data, the result of theoretic analysis was proved. Finally, the error's source between the simulate calculation and experiment test was found out based on comparing and analyzing the results of simulate calculation and those of experiment test.Results show that the absorbing bandwidth is enlarged and the absorbing capability is enhanced by embedding FSS in absorbing materials, moreover the programming process can be simplified by using MathCAD software, and the pre-estimate of the absorbing capability of the absorbing materials can be got. Therefore the efficiency of absorbing materials'design and manufacture is improved.