Electromagnetic Characteristics Analysis And Flaw Detection Of Radomes

The radome is a compact and weatherproof shell that can protect microwave and radar antennas from ice,freezing rain,wind and debris.It is an indispensable part of modern highspeed aircraft electronic systems.The function of the radome is to protect the antenna and radar system in the hood from damage from the harsh external environment,and to provide a transparent electromagnetic window for the antenna system.In harsh environments,the radome flying at high speed will suffer different damages,and the damaged radome will seriously affect the radiation pattern of the radome,which will directly cause the radome to fail to work normally.Establishing an accurate antenna array-radome integrated damage model,accurately calculating its radiation pattern,studying the pattern of change,and then performing flaw detection on the damaged radome are the problems that this article needs to solve.Aiming at the modeling and accurate calculation of the antenna array-radome integrated damage model,this paper is based on the high-order moment method and uses the parallel technology of the domestic Shenwei supercomputer to study the influence of the radome damage on the electrical performance.First,use HOMo M’s bilinear surface and meshing technology to process the radome model,then establish different types of damaged radome models,and finally calculate and analyze the change law of different types of damaged radome patterns.In addition,for the problem of radome damage detection,this paper uses time reversal technology as the theoretical basis to calculate the transmission matrix of the antenna array before and after the radome damage,construct the time inversion operator of the radome system,and then determine the damage position and thickness of the radome.Changes are detected.Based on the accurate establishment and calculation of the radome model,this article first analyzes the causes and types of radome damage,models and calculates the perforation,thinning,and ablation damage models of the radome,and analyzes the different types of damage to the radome.The pattern of the pattern changes.The results show that: perforation damage and thinning of the cover only have a greater impact on the transmission rate of the radome;ablation damage will reduce the transmission rate and increase the zero depth of the difference beam,and when the ablation area reaches At a certain value,the pattern of the radome is severely deformed,causing the radome to fail to work normally.Secondly,the theory of radome detection based on time reversal is studied,and the state response of radome damage is obtained by using the theory of time reversal operator.The experimental plan for radome damage detection is designed,taking A sandwich flat radome and cone radome as examples.For example,the DORT imaging method is used to locate and image the damage position of the radome.Finally,the transmission line theory is used to analyze the influence of the flat radome on the transmission coefficient and reflection coefficient.According to the actual application scenario,the thickness change of the incomplete radome after high temperature ablation is analyzed.First,the overall thickness of the tapered radome is measured.Cut 0.5mm to 2.5mm successively,with an interval of0.5mm,and then use the eigenvalues of the time inversion operator of the radome system under these 5 different thicknesses to determine the ablation thickness of the radome.