Waveguide arrays for low-frequency absorption and high-frequency transmission application

In this paper, a two layer composite structure with the properties of low-frequency absorption and high-frequency transmission is designed and verified. The absorbing frequency selective surface loaded with lumped resistance is firstly proposed, and then a layer of waveguide arrays with the spectral filtering characteristics of low-frequency reflection and high-frequency transmission is also introduced here on the below. The two layers of composite structure work together contributing the selective absorption and transmission of electromagnetic waves for specific frequency bands, which can be seen as a good achievement for the application of absorption-transmission integrated The structure of this design has the polarization-independent performance. Approximate full wave simulation of the proposed structure is carried out by using CST Microwave Studio software. Simulation results show that the absorption efficiency of the composite structure in the low frequency(5.6-12.3GHz) range is greater than 90%, the transmittance is higher than 80% at high frequency(16.2-17.8GHz), and the maximum transmittance is 85% at 17.1GHz, which meet our original targets. Meanwhile, the proposed structure has advantages of good absorbing and wide wave width, which can be seen as great application in the field of new stealthy radome.