Dual-Band Frequency Selective Surface Design Using Harris Hawks Optimization

Frequency Selective Surfaces (FSSs) are periodic structures that are designed to reflect, absorb or transmit electromagnetic fields in a variable frequency range. Their performance is strongly dependent on their fundamental structure, i.e. the unit cell. In this paper, we exploit the characteristic of absorption to design a dual-band FSS suitable for indoor RF energy harvesting systems. We combine an optimization technique by utilizing the Harris Hawk Optimization (HHO) algorithm and a high-frequency electromagnetic solver to optimize the geometry of the unit cell and the overall FSS. The proposed system operates in the frequency bands of Wi-Fi 2.4 GHz and Wi-Fi 5 GHz. Numerical results demonstrate that the optimized FSS exhibits quite satisfactory results and makes it a suitable candidate for RF energy harvesting applications.