Research On L-band Novel High Power Microwave Source Based On Metamaterial

L-band?1-2 GHz?electromagnetic wave is not sensitive to weather and terrain,and is widely used in military and civilian applications.However,L-band high-power microwave?HPM?sources face problems such as insufficient and low conversion efficiency.Metamaterial has advantage of miniaturization and is expected to improve conversion efficiency of microwave sources.This paper proposed a metamaterial HPM source to realize miniaturization and high efficiency of L-band HPM source.Firstly,the related theoretical study of metamaterial was carried out.New metamaterial construction method,the orthogonal arrangement of resonant units was proposed,and a novel of all-metal metamaterial was designed,which exhibits double negative properties near the?mode of the circular waveguide TM₀₁ mode;The metamaterial slow wave structure?MSWS?which based on the designed metamaterial can work below cutoff frequency of hollow metal waveguide with the same size,which has advantage of miniaturization.Secondly,mode analysis of the MSWS is carried out,and the fundamental mode is quasi-TM₀₁ mode,which has negative dispersion,and zero-order space harmonic is back-ward wave;the base mode has coupling impedance greater than 75?in whole working frequency band,and high conversion efficiency potential is obvious.Then transmission characteristics of MSWS and conventional SWS are analyzed and compared,which show the MSWS has obvious advantages in miniaturization.Thirdly,particle simulation was carried out.Beam transmission characteristics are analyzed,the space limit current is calculated,and the magnetic field is determined.Under the condition:U=550 kV,I=1.5 kA,B=2 T,obtained P=460 MW,f=1.366 GHz microwave output,with conversion efficiency of 55.8%.Working mechanism of the device is Cerenkov mechanism and working mode is quasi-TM₀₁ mode.The maximum internal field strength of the device is less than 1.2MV/cm.Related engineering design of L-band metamaterial BWO was carried out,a solenoid coil capable of providing 2T uniform magnetic field is designed.In order to experimentally study the transmission characteristics of MSWS,a coaxial TEM-rectangular TE₁₀ mode converter is processed and processed.Finally,the transmission characteristics of the MSWS are experimentally verified,which is roughly consistent with the simulation trend.This proves the correctness of theoretical analysis.