参数简化型折叠变换媒质散射特性仿真与研究

Simulation and Study of Scattering Characteristics of Folded-Transformation Media with Reduced Parameter Sets

为降低超材料实现难度,对参数简化型折叠变换媒质的散射特性进行了仿真研究。基于理想参数折叠变换媒质,提出了一种参数简化模型,简化后三个方向的非均匀性被集中到其中一个方向。有限元仿真结果表明简化参数型折叠变换媒质的散射放大效果与理想参数模型接近,保持了波束聚焦的基本特性;超材料的介质损耗对器件散射放大功能的影响较小。研究发现:该参数简化模型保持了一定的散射放大功能,但材料参数大幅简化,明显降低了实际制备难度,而且无需对超材料的损耗条件有苛刻要求,扩大了其应用范围。

To simplify the realization of metamaterial,the scattering of the folded transformation media with reduced parameter sets was simulated in this paper.Based on the ideal parameter model,a reduced parameter model was given,in which the un-uniformities in three directions were concentrated in one direction.The results of FEM simulations of the folded transformation media showed that the scattering magnifying function of the reduced parameter model was close to that of the ideal parameter model and the basic characteristic of beam focusing was well kept.The midia loss of the metamaterial media had little effect on the scattering magnifying function of the parameterreduced folded transformation media.The study indicated that the reduced model would maintain the scattering magnifying function of the folded transformation media and its media parameters were distinctly reduced which could obviously decrease the practical fabrication difficulties,and in the meantime there was no severe requirement to the loss conditions of the metamaterial media,which could extend the application of the reduced model.