Research On Transmission Characteristics Of Plasma Electromagnetic Based On Artificial Medium Structure

In this paper,uses artificial medium structure to study the transmission characteristics of electromagnetic waves in plasma from two different perspectives.The working principle and technical advantages of the magnetic window antenna based on artificial dielectric structure and periodic plasma columnar artificial medium structure are elaborated in detail.First of all,this paper introduces the urgent needs of mankind for the development of space resources and the blackouts?radio interruptions?that the aircraft faces during the reentry phase.Summarized the solutions proposed by domestic and foreign research institutes and scientific researchers on this issue and the technical measures adopted.Analyzed the limitations and existing problems of the existing programs and technical means,and derived the necessity and significance of the research.According to the radio interruption problem that occurred during the reentry phase of the aircraft,the plasma and the interaction between plasma and electromagnetic waves was studied.The plasma is considered as a medium and a theoretical model is established.The transmission characteristics of the electromagnetic wave in the plasma are analyzed by the model,the transmission conditions of the electromagnetic wave are obtained,and the effects of the applied magnetic field and the frequency of the incident electromagnetic wave on the propagation of the electromagnetic wave in the plasma are obtained.Reasonably explained the problem of communication disruption during the reentry phase of the aircraft.Then,through the analysis of the basic structure of the artificial medium structure and the magnetic window antenna,an artificial medium structure is proposed for the design of the magnetic window antenna.In the design process,microstrip antennas are used to satisfy a series of special requirements of the aircraft on the antenna,and the miniaturization of the antenna is achieved through technical means such as slotted slits and short-circuit loading.The resonant frequency of the artificial medium structure is designed to be above the operating frequency of the antenna,so that the artificial medium structural material can exhibit the characteristics of the inductive material.It excites the magnetic field in the near field,and supplements the electric field with the magnetic field to promote and enhance the propagation of the electromagnetic wave in the plasma.Finally,a magnetic window antenna with a center frequency of 2.63GHz and an electromagnetic radiation portion size of0.324?₀?0.324?₀?0.027?₀ was designed.Combined with traditional magnetic window antenna design ground contrast experiment.The experimental results show that the magnetic window antenna designed in this paper reduces the plasma attenuation to 14.01dB through a density of10^{1 1}cm^-3magnitude and a thickness of 80mm,which is 16.5dB lower than that of a traditional magnetic window antenna.Finally,according to the propagation conditions of electromagnetic waves in plasma,an artificial medium structure is designed in this paper.Its operating frequency is 2.6GHz.When the plasma density of10^{1 2}cm^-3 magnitude,S21 is-3.6db,which greatly promotes the propagation of electromagnetic waves in plasma.In the design process,in order to distinguish it from the traditional periodic plasma column,the working modes and working mechanism of the two are compared and analyzed,and the effects of various parameters of the design structure on the transmission characteristics of the electromagnetic wave in the plasma are summarized.Highlight the superiority of the design of artificial media structure in this paper.