Low And High Frequency Mixed Electromagnetic Shielding To Isolate Electrical Connectors

The application of advanced electronic equipment,such as radar of bilateral controlling matrix,electronic scouting satellite and so on,is more and more universal in modern war,so electronic war surrounding electromagnetic interference and interference suppression has become a crucial factor to determine the victory of war. Being one kind of particular connector,shedding electric connector is the main channel between the earth controlling equipment and electronic aid on missile.Moreover,it also is the only channel that electromagnetic interference in the missile radiates out of the missile and all kinds of electromagnetic interference outside come into the body of missile.Most of the shedding electric connector that we have known can perform a function of electromagnetic shielding only after mated,however,they will totally lose the capability of shielding at once when they are detached.So when the missile is flying in the air,it is very easy to detect and find the missile because of the special frequency electromagnetic wave radiated from missile.Meanwhile,all kinds of electromagnetic waves can enter into the missile through this channel,interfere with the scheduled flying trace,mistake the correct aim,cause wrong action,and finally make the missile lose its expected attacking capacity.In the new development position,in order to apply to the development of electronic war and improve the capability of interference suppression of arm system,it is urgently needed that the shedding electric connector can still have the capability of electromagnetic shielding after detached.The technology of electromagnetic shielding of shedding electric connector studied in this paper mainly involves synthesis argumentation and analysis of electromagnetic shielding structure plan,design of heat-resistant,design of electric(high & low frequency contacts design), study of detecting shielding effectiveness technology,design of reliability,design of assembly & disassembly tool and so on.In the aspect of electromagnetic shielding,there are various types and structure plans to accomplish electromagnetic shielding,and all of them that can be used in electric connector are plan of filter,plan of a metal casing and plan of closing wave-guide hole.Through the calculation,comparison and analysis of the structure composing,work principle,shielding effectiveness,application area and other main capabilities of various plans,we found that plan of filter and plan of a metal casing still have some unsteady and uncertainty aspects,moreover some of the index can not be totally satisfied.In the plan of closing wave-guide hole,once the diameter and the depth of wave-guide hole are ascertained,the shielding effectiveness can be sure,furthermore it is immunized from environmental influence such as temperature,vibration,impact and so on.It also has the good characteristic of simple structure,high capacity of bad environment resistant,stable and reliable,which is especially fit the dynamic environment in flying.Through the synthetic comparison and analysis,plan of closing wave-guide hole are chosen to accomplish product design in this paper.In addition, through the study of detecting technology of shielding effectiveness,finally,the shielding effectiveness of product satisfies the requirement in task book,and the function that the shielding effectiveness is more than 20dB in the frequency of 10kHz～0.03GHz and is more than 40dB in the frequency of 40dB,is accomplished.The principle of shielding,design of structure,detection of shielding effectiveness, heat-resistant protection,stability design and so on are totally understood through the study of electromagnetic shielding technology of shedding electric connector. Meanwhile the technical breakthrough of electromagnetic shielding in single part of connector is accomplished.Moreover the connector studied in this paper fills the vacancy of electric connector in home and abroad and meets the impendent requirement of special type.At the same time,the accomplishment of this study accumulates a lot of valuable experience for the later development of the same electric connector and it also propels the application of electromagnetic compatibility theory in the engineering practice of electric connector.