A new analysis of electromagnetic transmission characteristics of anisotropic honeycomb sandwiches

Honeycomb sandwiches are widely used as electromagnetic transparent materials for radomes. However, the electric anisotropy has a significant influence on the transmission performance. This work aims to investigate the electromagnetic transmission characteristics of the anisotropic sandwich panel. First, we deduce the effective permittivity of multilayered anisotropic sandwich material in the respect of the horizontal polarization and the perpendicular polarization components of the incident wave. Second, the transmission line network method related to the multilayered homogeneous medium is improved to simulate the electromagnetic transmission through honeycomb sandwiches and to calculate the transmission ratio. As the proposed method takes into account the three-dimensional anisotropy of each slab, it can simulate the transmission of plane wave with arbitrary incident direction in multilayered anisotropy sandwich panels, moreover, it can reveal the influence of material orientation on the transmission characteristics. Since the multilayer configuration is simulated by transmission line network, the proposed method is far more efficient than the finite element method. Numerical experiments indicate that the influence of the electric anisotropy on the transmission performance of honeycomb sandwich materials can be well revealed. In an incident angle range between 0 and 80 degrees, the simulation results fit well to the results obtained by the finite element method.