Mechanism Analysis And Suppression Approach Of Electromagnetic Leakage Of Interconnect Cables

Electronic equipment will unintentionally produce electromagnetic leakage,which will affect the surrounding equipment and the health of the staff.More seriously,the leakage of classified information will lead to incalculable losses in politics,economic and military.Electromagnetic leakage has been paid more and more attention by all walks of life,and it has two kinds of leakage,Radiation leakage and conduction leakage,in which the interconnection cables play an important role.In this paper,the electromagnetic leakage of the cable is taken as the research object.The main contents are as follows:(1)Mechanism Analysis and Suppression of Cable RadiationThis section mainly analyzes the radiation of signal cables.The calculation method of the unit length parameters(or parameter matrix)and the specific solution of the transmission line equation is studied.The radiation of the cable is solved by the electric dipole approximation method.The relationship between the radiation electric field and the working frequency,the length and height of cables and the distance of the monitoring points is studied,using the analytical model.Methods to restrain electromagnetic radiation of cables,transferring square wave signal,are studied from the aspects of excitation signal characteristics,cable routing parameters and cable type,using the simulation method.(2)Mechanism Analysis and Suppression of Cable CrosstalkThis section mainly analyzes the crosstalk coupling between signal cables and power cables and so on.Based on the three-conductor transmission line model,the crosstalk mechanism of the cable is analyzed,and the related factors of capacitive coupling,inductive coupling and common impedance coupling are clarified.The relationship between the crosstalk coupling voltage and the operating frequency,the length,height and distance of cables is studied.Methods to restrain crosstalk coupling of cables,transferring square wave signal,are studied from the aspects of excitation signal characteristics,cable routing parameters and cable type,using simulation method.(3)Analysis of The Influence Factors of Shielded Cables’ Shielding EffectivenessShielding the cable is one of the primary approaches of reducing electromagnetic leakage.This section studies the relationship between shielded cables’ shielding effectiveness and transfer impedance,and clarifies the influence factors of shielding effectiveness.The effects of braiding parameters,cable routing parameters,and the materials and number of shielding layers on shielding effectiveness are analyzed.The shielding performance of different types of cables is studied,and a cable with excellent shielding performance in a wide frequency band is obtained.