基于电磁超材料的微波单向传输圆波导设计

Design of Microwave Unidirectional Transmission Circular Waveguide Based on Electromagnetic Metamaterials

微波隔离器是微波系统中不可或缺的器件,常见的隔离器都采用了铁氧体旋磁材料配合吸收负载实现电磁波的单向传输。这种器件虽然可以使电磁波单向传输,但是并不能改善能量的浪费问题,还增加了系统的复杂度。针对上述问题,本文基于电磁超材料设计了一种微波单向传输的圆波导,使用波导内壁涂覆折射率逐渐变化的材料来影响电磁波的传输特性,从而实现电磁波单向传输。本文给出了微波单向传输的电磁计算模型和超材料结构及属性,并通过简化这种超材料使其易于实现;最后通过电磁仿真分析了这种材料的电磁特性并给出了这种材料的实现方法。

Microwave isolators are indispensable components in microwave systems. Common isolators use ferrite gyromagnetic materials to absorb loads to achieve unidirectional transmission of electromagnetic waves. Although this kind of device can transmit electromagnetic waves in one direction, it cannot solve the problem of energy waste and increase the complexity of the system. In response to the above problems, a circular waveguide for unidirectional microwave transmission is designed based on electromagnetic metamaterials. The inner wall of the waveguide is coated with a material with gradually changing refractive index to affect the transmission characteristics of electromagnetic waves, thereby achieving unidirectional transmission. The electromagnetic calculation model, metamaterial structure and properties of microwave unidirectional transmission are given, and the metamaterial is simplified to make easier realization. The electromagnetic characteristics of the material are analyzed through electromagnetic simulation and the realization method of it is given.