An Accurate and Fast Semi-analytical Modeling Method for Large-scale Metasurface

Accurate and fast modeling of large-scale digital coding metasurface is a significant problem in practical engineering applications. In this paper, the author puts forward a novel method to analyze the mapping between scattered waves and coding states, based on microwave network theory and statistics. By using the proposed method, the contribution of each coding state to the scattered wave is calculated, and a semi-analytical expression is obtained after retaining the main components. The pruned expression is a second-order polynomial of coding states, and thus has low computational complexity. However, the introduction of the second-order term takes the mutual coupling of the metasurface into account, so the accuracy is close to that of full-wave simulations. Therefore, a macroscopic model of digital metasurface with both efficiency and accuracy is established based on the semi-analytical expression. Full-wave simulations have verified the effectiveness and robustness of the modeling method. In the future, optimization and other means will be combined with the model, which makes metasurface play a more critical role in practical applications.