The Electromagnetic Characteristics And Engineering Applications Of Metamaterial

Metamaterial is one of the frontiers of Physics and Electromagnetism currently. Its unusual characteristics have attracted a great deal of attention of the researchers in and abroad to devote their works in the theory and application. So far, there are two approaches to microwave metamaterial. One is based on the array of the ROD and SRR (Split Resonant Ring), and the other is based on the left-handed transmission line. In this thesis, the unusual electromagnetic characteristics are analyzed based on these two approaches respectively, and the application of the left-handed transmission line in the microwave circuit is researched.Because the permittivity ε and permeability μ of the metamaterial are both negative, some unusual phenomena appear from it. Different from the usual media, the radiation field in the metamaterial behaves as the inward waves. In this thesis the characteristic of the inward waves has been studied on the electromagnetic principle of the far field radiation condition and the radiation power condition. It is shown that the inward wave is consistent with the causality. The FDTD numerical calculation method is used to simulate the propagation of the wave emitted from a power source inside a metamaterial cylinder which is composed of the ROD and SRR array. The characteristic of the inward waves in the metamaterial is conformed by the simulation results.The special characteristics of the left-handed transmission are analyzed, and its applications in the microwave circuit are studied. The balance and unbalance CRLH (Composite Right/Left-Handed) transmission lines are implemented with microstrip circuit, and they are used to ameliorate the conventional microwave devices. According to the design of Dr. Caloz, Some novel microstrip devices with excellent performance are simulated and fabricated, such as coupler and leaky-wave antenna. Based on the dual-frequency technology of the CRLH, a novel Wilkinson power divider is designed and fabricated, which is compact and can work on arbitrary dual frequencies.