Research On Electromagnetic Scattering Control Theory And Technology

Thesis mainly studies the electromagnetic scattering control technology.Based on three methods,the stealth or scattering control of the target is realized.The electromagnetic cancellation and electromagnetic camouflage are studied by the equivalent principle;the scattering decomposition,scattering cancellation and impedance optimization are realized by the antenna scattering principle;the reflected beam is controlled by the equivalent impedance model of the metasurface.After analyzing the equivalence principle,two schemes that can realize electromagnetic cancellation—external source equivalent method and internal source equivalent method are designed,and a scheme for electromagnetic fraud is extended;first,a two-dimensional infinitely long metal cylinder is used for example,through the Method of Moments programming experiments,the feasibility of the scheme is preliminarily verified;secondly,through commercial simulation software,the two electromagnetic cancellation schemes are simulated by using the metal ball model,the metal cube model,and the aircraft scale model.And the two methods are compared through the results;finally,multiple models are used to simulate electromagnetic fraud to verify the correctness of all schemes.As the specific implementation of the equivalent source is mainly the antenna,the scattering principle of the antenna is also studied.Firstly,three commonly used classical scattering formulas are deduced according to the scattering matrix model of the antenna,the influencing factors of the antenna scattering are studied,and the relationship between the structure term scattering and the mode term scattering,and the gain frequency is analyzed and verified;secondly,the Green antenna scattering formula,a specific implementation scheme for separating and verifying the scattering of the antenna is designed,and simulated by the Vivaldi antenna model;finally,according to the antenna scattering separation formula,the impedance formula that satisfies the cancellation of the structure term scattering and the mode term scattering is deduced,and then the calculation and simulation are carried out to optimize the solved impedance value,and the optimal impedance curve of the antenna in the broadband is obtained,and a software to realize the antenna scattering separation is designed.Finally,the current hot spot of the electromagnetic regulation-artificial electromagnetic surface is studied.Firstly,according to the Huygens surface principle,the theoretical formula of the equivalent impedance model of the metasurface is deduced,including the reflection control of single beam and multi-beam;The deflection of a single beam is studied,and then the relationship between the deflection angle of the reflected wave and the error is studied;secondly,the multi-beam deflection of the electromagnetic wave is realized,and the deflection angle is changed from the one-dimensional direction by designing an equivalent impedance array model.It is extended to the two-dimensional direction;finally,a specific metasurface unit is designed according to the equivalent impedance model for simulation,and the regulation of the electromagnetic beam by the metasurfaces array is realized.