The Theoretical Research And Realization Of X Band Plasma Filter

Filter is the key problem of many wireless communication designs and requested many new and especial performances by the development of modern communication, such as wideband, high-speed adjustability and large power capacity. Meanwhile, the plasma microwave devices are widely studied because of their small volume, electromagnetic tunable and large power capacity, etc.Based on the model propagation theory in plasma filled waveguide, the excitation of electromagnetic waves is studied. The difference of excitation for plasma filled waveguide and conventional waveguide is pointed out. By use of excitation close to the end side, the propagation model is excitated successfully and the results are demonstrated by numerical simulationBased on the dispersion relation of plasma, the propagation of waves in nonmagnetic plasma and inhomogeneous media with cosinusoidal distributing dielectric constant is analyzed and a brand new X band filter is designed. Furthermore, the adjustability of center frequency and bandwidth is realized by adjusting the plasma density, which demonstrates the possibility of electrical tunable of plasma filter. The realization of X band plasma tunable filter gives theoretical and technical reference for the research of new microwave filter.