关键词: 人工电磁材料, 左手介质(异向介质), 等效电磁参量提取, S参数提取法

Abstract: This paper presents a novel improved method to retrieve the effective constitutive electromagnetic parameters of metamaterials based on the investigation of traditional S-parameter retrieval method. This method can be applied to both left-handed metamaterials(LHM) and traditional right-handed metamaterials. The improved method possesses three advantages. 1) The improved method employs inverse sine function to retrieve effective refractive index n. It can obtain the correct sign of n naturally without the additional constraint conditions n^" ≥0 and z^' ≥0 . It can avoid the potential errors of judgment induced by using the above two conditions. 2) It gives a very clear and definite solution to select the correct branches of the multi-value inverse sine function, which solves the well-known“branch” problem of traditional S-parameter retrieval. 3) The proposed method can be used to both thin and thick meta materials. It overcomes the limit that the traditional S-parameter retrieval works well only for thin slabs. The proposed method is applied to homogeneous double-negative and double-positive slabs, as well as the typical SRR-rods LHM. The successful retrieval results prove the correctness and effectiveness of the proposed method.

Key words: metamaterial, LHM, effective electromagnetic parameter retrieval, S-parameter retrieval