The Frequency Selective Electric-property Design And Realization Of Airborne Radome

Frequency selective surfaces (FSS) is a kind of periodic metal structure in1D or2D direction. It can’t absorb electromagnetic energy, but can effectively control transmission and reflection character of electromagnetic wave, substantively is a kind of space filter. It has important application in science and engineering domain, is getting attention of researcher all the world.Airborne radome is protection device of airborne radar. As a part of airplane, demand it keep aerodynamic shape, bear flight load, tolerance flight environment, and as electromagnetic windows of antenna, demand it promise regular work of internal antenna. Based on the above function, FSS airborne radome express metal character in the specified frequency band, shield internal antenna system’s strong scattering. Combining with streamlined contour of radome, it can satisfy aeroplane’s stealth requirement.The article research electic-performance design and realization for FSS airborne radome. Through the research for form mechanism of frequency response^frequency response and analysis method in FSS element’s parameters, such as size> periodic arrangements layer number, and so on, we can find the FSS element with better incident angle and polarize stability which is suitable for airborne radome. We make research on FSS radome’s basic design element, put forward to realize design rule in large incident angle、constant band width and stable polarization and the method which restrain grating lobe. Pointing to streamlined contour characters of airborne radome and electric-property requirement, we firstly analyze radome’s incident angle distribution and polarized characters, and confirm two layers FSS/A sandwich dielectric loaded structure through the research of compound method with FSS and dielectric loaded structure. We select composite material with better dielectric properties and mechanical properties, and adopt Finite Element Method(FEM) electromagnetic simulation and analysis software to design、simulate and optimize FSS equivalent plate’s frequency response. We compare with simulation and measure result, both are in good agreement. The result which to simulate FSS radome’s bandpass transmission、pattern characters and bandstop cut-off characters with FEM/PO mix algorithm software indicate the designed FSS radome has good bandpass high-transmission, low patter distortion and bandstop high cut-off characters, realize stealth effect to antenna system in bandstop. The mix algorithm software in this article give consideration to computational efficiency and accuracy, has high engineering value.Main works in the thesis:1. The research of periodically FSS analysis method, compare and analyze with different type FSS cell’s resonant frequency、frequency response and bandwidth character, find FSS cell type、grid arrangement and layer number parameters which is suitable for airborne radome.2. The research of FSS radome basic design elements, put forward to realize design rule with large incident angle、constant bandwidth and stable polarization and the method which restrain grating lobe.3. Research FSS radome’s design flow, use mix simulation and analysis method based on FEM and PO to simulate FSS radome’s electric-property.