| With the development of communication and plasma technology, the research of using the plasma antenna to replace the traditional metal antenna in the communication system becomes one of the hotspot in related fields. Thus the dynamic reconfiguration of the plasma-column antenna in the HF/VHF range is focused for different plasma parameters. This thesis covered the contents about the basic theory and CAD of plasma-column antenna, numerical calculation of plasma-column antenna electrical parameters, and also measurement and analysis of plasma-column antenna input impedance, noise temperature and gain. The aim of these works is to confirm the possibility of realizing plasma-column antenna dynamic reconfiguration, so that the theoretical principle and technological preparations for the application of plasma-column antenna should be made.Presently, the author has realized the mechanical design of original plasma-column antenna system, accomplished the numerical simulation of the radiation characteristics of plasma antenna based on two-dimensional moment method, created the special measuring system for plasma-column antenna electrical parameters. The author's major contributions are as follows:1. The coupling structure of plasma column antenna was presented based on the elementary theory of surface wave plasma excitation and the propagation characteristics of surface wave in plasma. Then the design of plasma-column antenna system is realized according to the simulation results of the electromagnetic property of excitation and signal frequency inside the structure, including the plasma parameters, the dimension of plasma-column antenna, the coupling modes and the HF/VHF filters .2. The numerical analyses of the radiation characteristics of a plasma-column antenna is presented by using the moment method when the operating frequency is greatly lower than the plasma frequency, including current distribution along the plasma column, radiation pattern, input impedance, antenna efficiency and gain. It has been demonstrated that the plasma antenna can operate similar to a copper antenna, and the radiation characteristics can be varied by varying the plasma parameters.Furthermore,not only the dynamic reconfiguration of the plasma antenna, but also selecting fixed plasma parameters with reduced efficiency enables the wideband characteristics of plasma antenna.3. The ionization impedance of the exciting channel of plasma-column antenna was calculated based on the VSWR calculation for different applied RF power. Then an impedance matching electro circuit of this channel was designed, which made the VSWR always less than 2 for different applied power.4. The input impedance of the signal channel of plasma-column antenna in high exciting power was measured by a new method, which is useful to the study of plasma antenna dynamic reconfiguration and the realization of fast impedance matching. The changes of the input impedance of the signal channel of plasma-column antenna with frequency have been measured by the vector network analyzer for different applied RF power. The relationship between the impedance curves and the plasma parameters was proposed by using the equivalent circuit model and the characteristics of input current. The experimental result shows the resonance behavior of the impedance curves is prominent. A broadband matching electro circuit was designed by the software, and then a hardware matching electro circuit was realized in the HF range, which validated the broadband characteristics of plasma-column antenna.5. The noise source and magnitude which affects the performance of the communication system was discussed when the plasma antenna replaced the traditional metal antenna. Then the noise temperature of the plasma antenna feed was measured in two methods by using RF communications test set and Spectrum Analyzers. The result shows the plasma antenna can be used in radio communication instead of metal antenna.
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