Research On Equivalent Electromagnetic Parameters And Reflection Parameters Of Honeycomb Absorbing Materials

Stealth technology has been widely appreciated in today’s military applications. It can effectively reduce the possibility of being attacked by precision-guided weapon systems. So it greatly improves the performance of concealing military targets and the capabilities of penetration and attack. As one of structural radar absorbing materials, honeycomb structure becomes a research trend of military development because of its light weight, high strength and stiffness, good thermal insulation and shock absorption, excellent absorbing performance and many other advantages. It both can be used as load-bearing parts and sandwich layer of absorbing material.Reflection coefficient is an important indicator of the properties of absorbing material, so we calculate the reflection coefficient to study the performance of honeycomb absorbing materials.Originally, the reflection coefficient of cellular absorbing materials is measured by the experiment.However, the process of experiment is complicated, time-consuming and laborious. It undoubtedly extends the period of research. With the fast development of computer technology, honeycomb material is mostly studied by the methods of numerical simulation, including the method of moments, finite difference time domain method, finite element method, genetic algorithm and so on. These methods effectively solve the problem of experiments. This paper derives the formulas of equivalent electromagnetic parameters(parallel and perpendicular directions) as well as the reflection coefficient.The main content of this paper is:1. It respectively introduces the theory of strong perturbation and reflection coefficient of the absorbing material. This paper deduces inside and outside scattering field in the medium in which the permittivity and permeability is randomly distributed. It also deduces the formulas of reflection coefficient when the absorbing material does have a metal substrate or not. 1.It respectively introduces the theory of strong perturbation and reflection coefficient of the absorbing material. This paper deduces inside and outside scattering field in the medium in which the permittivity and permeability is randomly distributed. It also deduces the formulas of reflection coefficient when the absorbing material does have a metal substrate or not.2. Based on the theory of strong disturbance, this paper derives equivalent electromagnetic parameters which is parallel and perpendicular to the axial direction of honeycomb. According to the honeycomb reflection theory, the reflection coefficient is also obtained when the incident wave is shining on the honeycomb holes or side walls, and in the cases of different polarizations(TE or TM waves).3. According to the formulas of honeycomb reflection coefficient in different circumstances, the paper calculates the reflection coefficient by writing a program with VS2010 software. With this program, the paper can analyze the influence of various parameters on the reflection coefficient of honeycomb. The values of parameters can be obtained from the program when the reflection coefficient is best.The result calculated by the written program has little difference with the experimental results and the trend is consistent. Therefore, this method can be considered feasible to research the reflection coefficient. The method in this paper can provide a reference for research about the properties of honeycomb absorbing materials and its structural design.