Study On Electromagnetic Characteristics Of Cylindrical Cavity With Apertures

With the rapid development of information and science and technology in recent years,the electromagnetic environment in which various electronic devices are located is becoming increasingly complex,and the electromagnetic interference problems brought by them have also received more and more attention.In practical engineering applications,due to the existence of structures such as doors and windows,wire exits,and covers,various electronic equipment and systems include structures with apertures.Such structures will provide a coupling path for electromagnetic energy and affect the electromagnetic environment inside and outside the system.Therefore,the research on the coupling problem of apertures is of great significance.In the problem of aircraft platforms,warships and other weapon platforms,many structures that include apertures are cylindrical cavities.This article focuses on the electromagnetic characteristics of the inside and outside of the cylindrical cavity with apertures.The main contents include the following aspects.(1)An algorithm is implemented for solving the coupling effect of cylindrical cavity with apertures.An equivalent model is established by introducing an equivalent magnetic current at the aperture instead of the original excitation source.And the equivalent magnetic current is obtained by solving the equivalent model.The calculation formula of equivalent magnetic current is given,and the electromagnetic scattering characteristics of cylindrical cavity with holes are solved by equivalent magnetic current.Finally,numerical examples are given to verify that the algorithm has similar calculation accuracy and efficiency as Feko.(2)The effects of the position and geometric parameters of the apertures to the cylindrical cavity are studied.Based on the method of moments,the simulation software Feko was used to simulate the coupling energy distribution inside the cavity.And the shielding effectiveness of the cavity was estimated and verified by experiment.The results show that the closer the cavity is to the aperture,the more coupling energy is received.For a rectangular aperture on a cylindrical cavity,the shielding effectiveness of the cavity is best when the aspect ratio of the slot is 1: 1.(3)The software compilation of the coupling algorithm of the cylindrical cavity is realized.To facilitate engineering applications,the software is divided into component modules,iterator modules,and solver modules.The operation process of the software is given,and the specific functions and dependencies of each module are explained.