Study Of Coupling Effect And Propagation Mechanism Of High Power Microwave Pulse

Coupling effect and propagation mechanism of High Power Microwave (HPM) pulse are studied in this dissertation. Because these problems belong to transient electromagnetics, the finite-difference time-domain (FDTD) method and the pseudospectral time-domain (PSTD) algorithm are applied. The results show the rules of HPM pulse coupling into cabinet with slots and propagation in the atmosphere. It will be useful to theory and project applications of HPM pulse coupling into shielding cabinet and propagation in the air.At first, the applications of HPM pulse in the electronic warefare are introduced. And the characteristics of HPM coupling effect on electronic devices and HPM propagation in the air are introduced. The introduction of these problems shows that it is a challenge to do researches on HPM coupling effect and propagation mechanism.As the foundation of this dissertation, the analytical methods of the ultra-wide-band (UWB) signal are introduced. The FDTD method is excellent to analyze the UWB signal. The absorbing boundary conditions of FDTD method are analyzed and improved.The FDTD method is applied to study the coupling effect of UWB pulse into the cavity with slots which have various slot shapes but same areas. The results are useful to design the shielding cabinet. In order to characterize the slots and save the computer memory, the combination of subgridding algorithm with FDTD method and the parallel DD-FDTD algorithm are applied to model the UWB pulse coupling on cabinet with slots respectively. The results show these methods are efficiency. Because of the importance of transmitting repetitive HPM, the coupling of repetitive UWB pulse into the cabinetthrough slots is studied. Because the coupling effect of HPM pulse into computer is of stratagemical significance; the electromagnetic penetration of UWB pulse into computer case is researched. The results are useful to electromagnetic defends. At the same time; the rule of coupling effect of repetitive UWB pulse into the computer case is analyzed.The FDTD method is applied to analyze the propagation of HPM pulses in air breakdown environment in the atmosphere. The phenomena of tail erosion and air breakdown are found by using numerical simulation. The PSTD algorithm is applied to study the propagation mechanism of HPM pulse in the ionosphere. The phenomena of HPM pulse propagation and reflection are found in the ionosphere.In the last part of the dissertation; the study of coupling effect and propagation mechanism of HPM pulse is summarized; and the development directions of the investigation are predicted.