高功率波段基于零折射率材料的波前相位改善

Wavefront phase improvement based on zero-refractive index metamaterials in high power band

摘要:

零折射率材料作为超材料的一种在微波辐射中有广泛应用。为实现高性能的小型化天线，分析了零折射率材料的产生机理，设计了一种高功率金属网格材料天线透镜。数值模拟表明，零折射率材料透镜覆盖于一Ku波段喇叭天线口面时，可以改善喇叭天线波前相位，将喇叭天线的球面波前相位调制为较均匀的平面波，增益可提高2.27 dB，喇叭天线的功率容量可达到610 MW。研究了材料的层数n、层距h、周期a以及金属线半径r对S参数的影响，得到了所要求频率的最优材料结构。

Abstract:

Zero-index meta-materials have been investigated extensively for their unique electro- magnetic properties. In order to achieve the miniaturization of high performance antenna, a kind of zero-index material is designed, i.e., metal-mesh structure, by adjusting the effective plasma frequency to the desired frequency band. The numerical simulations indicate that this metal-mesh structure can improve the wave-front phase and increase the gain when this structure is introduced to a horn antenna. The front wave phase of the antenna is changed from the spherical wave to the plane wave, the corresponding gain of the antenna is increased by at least 2 dB. The effect of the geometrical parameters, including the number of mesh layers n, the distance between adjacent layers h, the period a for a single mesh layer, and the radius of the metal lines r, are investigated systematically to optimize the directional emission.