Study On Coupling Effect Of Complex Aperature Based On Electromagnetic Topology Theory

With the rapid development of electronic technology and the increasing complexity of the electronic circuit,the electromagnetic environment is becoming worse and worse,which is the key factor to ensure the stability of the system.Therefore the key factor to ensure the stability of the system is to overcome the degradation of the performance of the sensitive equipment.Although sensitive equipment is mostly shielded,due to shielding cavity on the surface of the slot or hole for cable connection,ventilation and heat dissipation,which makes the research on the calculation method of the shielding effectiveness of aperture slot cavity becomes a hot issue.In this paper,a hybrid method of the shielding effectiveness of aperture slot is proposed based on electromagnetic topology theory.It can quickly and accurately calculate the shielding effectiveness of arbitrary incident,arbitrary polarization plane wave radiation cavity,and the shielding effectiveness of the open hole and the double side aperture cavity,and consider the coupling effect between the holes.Firstly,according to the equivalent circuit method,the cavity aperture is equivalent to two port network,and the scattering matrix is obtained by using K irchhoff's law.The signal flow diagram of the circuit model is drawn based on the electromagnetic topology theory,and the propagation relation equation and the scattering relation equation are obtained,Then the generalized BLT equation describing the whole physical model is derived,and the electromagnetic field at any point in the cavity can be obtained.Then,in order to make the results more accurate,several kinds of errors are analyzed in this paper.The method of scattering matrix is improved,and the hole slot is equivalent to rectangular waveguide by pattern matching method.In the discontinuous boundary,the method of complex power conservation is used to analyse the unknown electromagnetic field components,through solving the coupling coefficient,the scattering matrix of the hole is obtained.Finally,in this paper,the situations of the transmission line with holes in the cavity are studied,The necessary theoretical basis is provided through simulation.