Research And Design On Metamatiarals And Substrate Integrated Waveguid Based Antenna

Researches on metamaterials and substrate integrated waveguide have just been ascendant. Scientific researchers are continuously study their application in the antenna field to play their respective advantages, and continue to improve the performance of all kinds of antenna. The metamaterials have the characteristics of the permittivity and permeability simultaneously negative, leading to its negative refractive index. The metamaterials can not only improve the antennas’ gain and directionality, but also can reduce the size of the antennas. These advantages make the metamaterials easily to adapt to the rapid development of wireless communication technology.Firstly, this thesis introduces the research background and significance of the metamaterials and substrate integrated waveguide. The basic theory of matamaterials is researched, the several "singular" electromagnetic properties of metamaterial are discusses at the same time. And then this paper discusses the basic theory of composite right/ left-handed transmission line and substrate integrated waveguide. The leaky wave antenna radiation theory, including the theory basis of lobe scanning, is introduced in this thesis. The design and realization method of metamaterials is provided in this paper. Four kinds of improved composite right/left-handed and substrate integrated waveguide leaky wave antenna are researched, and their unit structure of their dispersion curves and Bloch impedance respectively are researched, and the dispersion curve diagram and Bloch impedance diagram are drawn by using HFSS. And the unit structure’ equivalent LC circuit diagram and its principle analysis of circuit diagram is provided. The method for extracting the equivalent electromagnetic parameters of the unit structure is given in this thesis, and the effective electromagnetic parameter curve isn drawn by using Matlab software programming. Then the performance of the overall leaky wave antenna is researched, providing the comparison figure of measurement and simulation S parameters, radiation pattern analysis, analysis of bandwidth and lobe scanning range. This thesis compares their performance with the leaky wave antenna antenna in the 3.2 chapter, to find the performance advantage of the proposed four antennas.Finally, summarizes the theory of fractal structure, providing the definition of the fractal structure and the realization of fractal method. Then the fractal CRLH transmission line structure of antenna is researched, with the dispersion curve and the Bloch impedance of this antenna unit structure, and successfully extracting the effective electromagnetic parameters of this antenna unit, to prove that the unit is the metamaterial structure. The 8 unit fractal CRLH antenna is researched, and the analysis on its performance is made.