Research Of Echo-enhanced Harmonic Generation Traveling Wave Tube

In recent years, researchers have paid more and more attentions to terahertz science. Terahertz wave takes a special place in electromagnetic wave spectrum. The study on terahertz wave means a limitless application prospect and important academic value. Nowadays, terahertz technology has been widely used in biomedicine, astronomy, communication, military and so on. Unfortunately, lack of miniature and powerful terahertz radiation source is a serious impediment to its development.In this paper, we have made in-depth study and analysis in a new type terahertz radiation source—Echo-enhanced Harmonic Generation Traveling Wave Tube(EEHGTWT) which is miniature and tunable. Our research purpose is the echo-enhanced high harmonic generation in nonlinear electron beam and its application in terahertz multiplier Travelling Wave Tube(TWT). We want to reveal the regulation of nonlinear electron beam, the generation of harmonic and the choice mechanism. Those works will lay the foundation of the new type terahertz radiation source device’s development.The following contents have been studied in this paper:1. The introduction of the basic theory of Free Electron Laser(FEL) and some kinds of work pattern for FEL. We focused on the structure and principle of EEHG work pattern.2. The dispersion and interaction impedance characters of Folded Waveguide Slow Wave Structure(FWGSWS). We put out an optimized method for designing FWGSWS. Then analyze the beam-wave interaction in FWGSWS by nonlinear theory.3. We made a detailed theoretical analysis for EEHGTWT. Then we use HFSS and CST software for simulation. The parameters of SWS were optimized according to the dispersion and interaction impedance simulation result by HFSS. The beam-wave interaction process was simulated by CST. Some important parameters were changed to get some rules about those parameters’ influence to the result. The simulation result shows: we can get 5mW output signal which is mainly composed of 1THz signal. The frequency of the two input signal are both 100 GHz, the power are 1.15 W and 0.72 W. The work voltage is 24.5k V and the beam current is 4mA.4. Summarized the previous work and pointed out the questions we met in researching. Put out the work for the next step.