Desenvolvimento de estruturas irradiantes de ordem zero e inspiradas em metamateriais.

Abstract

In this thesis are developed some devices radiating in the application of the theory of metamaterials. Metamaterials are materials which until then cannot be found in nature, but can be constructed artificially, and are made in its majority of metal and dielectric. A brief historical chronology of the theoretical foundation of metamaterials is presented, based on the equations that govern the electromagnetic behavior in conventional materials. This work has as contributions some radiating devices which are designed and developed for use in wireless systems. These were conceived with the application of the metamaterial theory governed by parameters of transmission line. The first structure is ZORW (Zeroth-order resonating wire) antenna, designed with the use of a characteristic of metamaterials, which is the wavelength infinity. In agreement with this characteristic the structure size not dependent upon wavelength, but only of the inductances and capacitances present in the structure. The second radiating structure is the MIWA (Metamaterial-inspired wire antenna) antenna, developed from modifications of the ZORW antenna. After these changes the antenna lost the metamaterials characteristics, and with this became a metamaterial-inspired antenna. As a result of the changes the new antenna now has dual-band characteristics, and operates in the range of 2.45 GHz and 5.5 GHz. Consistent results are obtained in the frequency bands desired. Were used for simulation and the CST Microwave Studio and the FDTD (Finite Difference Time Domain), developed for simulate some of the structures. The antennas are projected for use in equipment that supports the standards of the IEEE 802.11 family, known commercially as equipment for wireless networks.