Studies On The Theory And Experiment Of Holographic Antenna

In the communication systems, high gain and low sidelobe are required for antennas to transmit the signal better and reduce the influence of electromagnetic radiation on other communication equipments. Moreover, better concealment is needed for antennas in order to improve the survivability of the communication equipments in the battlefield. Although the gain of traditional reflector antennas is high, their fixed outlines make them easier to expose their locations and reduce their viability significantly in the war.Holographic antennas are a kind of aperture antennas which utilize holographic structures to change the radiation property of the source antenna and achieve the radiation property of the target antenna. Different parts of the holographic structures can be chosen according to different application environments to achieve the integration of the antenna with the background. While avoiding the high loss of feed, the overall structure of holographic antennas is relatively simple. These advantages make holographic antennas break through the restrictions of structural outline on the antenna applications and have more invisibility.On the basis of the principle of constructing holographic antennas, this dissertation has analyzed the interference of the source antenna and the ideal plane wave to determine the locations of the holographic structures and composition of the holographic antennas. At the same time, with the simplification of calculating the minimum points of interference, the expression bearing universal meaning for calculating the locations of the holographic structures has been derived.As an example, the holographic structure made of metal conductors and a dipole are used to design and construct simple one-dimensional, two-dimensional and quasi three-dimensional holographic antennas in this dissertation. Their radiation fields have been simulated and measured. Calculated and measured results are in good agreement, which shows that using holographic structures can improve the radiation performance of the source antenna to some extent. Finally, possible applications and improving methods of holographic antennas are discussed.