Research On Theory And Technology Of Plasma Directivity Stealth Antennas

As a novel antenna bases on new conception and new theory, the plasma stealth antenna is one of the hottest research targets in antenna stealth technology and it is also a low radar cross section antenna different from the structure of traditional antenna. So the plasma antenna have a highly application value in the military field.Firstly, the principle of FDTD, the characteristics of XFDTD are discussed in this thesis. The plasma applications in XFDTD and the antenna impedance match are also involved in the thesis. The fundamental physical characteristics of plasma and plasma antenna are particular analyzed through the simulation of basic models, including the excitation of plasma, the plasma characteristics of reflection, radiation and stealth.As far as the plasma windowing directivity antennas are concerned, the ability of stealth and directivity are implemented by making full use of the plasma characteristic. The operating principles and structure of it are presented in this thesis and then the different radiation patterns and antenna gain are given by simulating different antenna models under different parameters. Some summary are also obtained from the simulation results.An electronically steerable plasma yagi antenna is proposed. The length and the conductance of antenna's components, the directivity and the effect of stealth are electronically steered. The different radiation patterns and antenna gain are given by simulating different antenna models under different parameters. The feasibility of this antenna is validated.As far as the plasma helix antennas are concerned, the ability of stealth and directivity and the high directivity of helix antenna are realized by making full use of the plasma characteristic. The characteristics and simulation results of these antennas are investigated by simulating the different helix antennas with different number of helix, the different types of ground and the different plasma's parameters.In addition, experimental sample of plasma reflector is implemented. The plasma frequency of it is measured and the performance of plasma reflector is analyzed through comparison of the peak value of spectrum in the two switch status of reflector.At last, some conclusions are summarized based this thesis, and the directions of future research are also point out.