Electromagnetic Pulsecable Couplingresearch Based On The BLT Eqaation

Electromagnetic pulse is a kind of electromagnetic wave with hard and soft kill probability,which will produce potential harm and permanent damage to electronic equipment. Then cable is the main channel of the electromagnetic pulse coupling, so the research method of the electromagnetic pulse cable coupling is become more and more.Firstly, on the basis of the transmission line theory, BLT equation is deduced and established, which includes the specific form under the lumped and external excitation source,meanwhile this paper gives clearly physical means and computational methods about BLT equation parameters.Secondly, based on the theory and algorithm of BLT equation, through simulation, we analyze the terminal response of double parallel conductors transmission cable, the non parallel transmission lines and three conductor transmission cable.The results show that:Under the condition of parallel double conductor, the coupling response of electromagnetic pulse on the cable terminal is has positive correlation to the incident angle of electromagnetic pulse wave,the distance between transmission cable, the length of cable,the radius of cable,however terminal load will produce negative correlation to coupling response. When analyzing the crosstalk between the parallel transmission lines and three conductor transmission cable terminal response, we will compare the terminal response of BLT equation with the method numerical algorithm FDTD, the results of two methods have very high coincide, thus this paper verifies the effectiveness of BLT equation to calculate the electromagnetic cable coupling response, this makes the BLT equation has certain practical reference value in the practical application.Again, building simulation platform, through the simulation, we analyzes electromagnetic pulse coupling response on the cable inside enclosure with aperture.The results show that:electromagnetic pulse produces coupling response on the cable which has positive correlation to the size of the aperture. And we choose single wire and twisted-pair cable as research object, the shielding effect of twisted-pair has 20 db more than single wire. These results willhave certain guiding significance to electromagnetic pulse protection theory and technology.