| The rapid development of modern radio systems promote the antenna system towards low cost, ease of integration, miniaturization and high-performance direction, which spawned a number of new ideas, technology into the antenna design objectively. Artificial electromagnetic materials (Metamaterial), as a frontier and interdisciplinary research field, have potential prospects. As a kind of two-dimensional Metamaterial, artificial impedance surface has the advantages of easy realization, low profile and so on. From the analysis the calculation method of artificial impedance surfaces, the theoretical analysis, design and calculation method of artificial impedance unit cell have been presented. Based on the microwave holography, the method of calculating the distribution parameters of the surface impedance is presented, and the modulation of the amplitude and phase of the surface wave is realized. Theoretical, simulated and experimental results have been presented, good agreement between simulation and experiment has been observed.The first part mainly studies the basic principles of artificial surface impedance, construction method, and electromagnetic response characteristics. Firstly, based on the scalar artificial impedance element, a novel tensor artificial impedance element is presented. The surface impedance of tensor artificial impedance unit cell is calculated by using the equivalent transmission line method, and the accuracy of the calculation is verified by the scalar impedance in different propagation direction of the tensor impedance unit. Secondly, the influence of the conformal structure on the surface impedance of the artificial impedance element is analyzed, and the feasibility of using the planar surface impedance to design the conformal antenna is verified.The second part studies the surface impedance distribute parameters of holographic antenna. Based on the principle of holographic optical, the surface impedance distribute parameters of different antennas are presented. The polarization, shape and the beam radiated direction of holographic antenna are controlled. Secondly, the union of modeling with simulation technology of Matlab-HFSS is used to realize the design and simulation of large complex electromagnetic model. Finally, the scalar and tensor artificial impedance element are used to design holographic antenna. The modulation of surface wave amplitude and phase are realized, and the related design theory is verified by the measured results. |
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