Research On Microstrip Antenna Based On Left-handed Material

Left-handed material is a kind of novel synthetic material, whose permittivityεand permeabilityμare simultaneously negative. It is different from the traditional right-handed material, whose electric field, magnetic field and wave vector satisfy the left-hand rule, which means the phase velocity and group velocity are in the opposite directions, so they have many unusual properties, such as negative refraction of light, reversed Doppler effect, reversed Cherenkov radiation, the perfect lens effects and etc. The development of the left-handed material has been regarded as one of top ten scientific and technological breakthroughs in science community in 2003, and has been the cutting-edge in the field of electromagnetic research.In this paper, realization and applications of microstrip antennas with Left-handed material are investigated by theoretical analysis and numerical simulation. We propose two novel composite right/left-handed transmission line units which can be applied in 3.5GHz wireless access system and 5.8GHz system with significance of practical applications.First, this paper briefly introduces the basic principles of left-handed material, as well as the research progress of left-handed material at home and abroad. Second, the traditional cross-finger structure has been optimized simulation on the basis of composite right/left-handed transmission line circuit model. A center frequency at 3.6GHz microstrip leaky wave antenna is designed, whose beam of radiation has the ability to scan from the back to the front. It has verified the structure of antenna has left-handed material properties. Then, two innovative structural units are putted forward based on traditional cross-finger structural unit:L-type cross-finger structural unit and cross-finger ground structural unit. Through simulation and optimization of L-type cross-finger microstrip antenna, the antenna work in the 3.5GHz frequency is designed. The antenna can be used for 3.5GHz wireless access system with 26.5% size of traditional patch antenna at same frequency. It also has good radiation gain, which achieve the miniaturization of the antenna. In addition, aim at cross-finger structural unit, a microstrip antenna work in the 5.8GHz frequency is designed. The antenna can be used for 5.8GHz system with 28% size of traditional patch antenna at same frequency. It also has good radiation gain, which achieve the miniaturization of the antenna. Furthermore, through extraction of S parameters,the dielectric constant and magnetic permeability of all the antenna above are calculated, which verified all the antenna have the characteristics of left-handed material.Finally, the paper sum up the work and make a certain outlook of future work.