Research Of The Complex Electromagnetic Environment Coupling To The Cables On The Warship

There are various electronic devices on the warship in a complex electromagnetic environment, including not only the radiation field of the antennas on the warship, but also the other electromagnetic interference outside the warship system. Cables, the connection circuits between the various subsystems, are inevitably exposed in the complex electromagnetic environment on board. And a large number of interference electromagnetic energy couple to those systems through the cables. Therefore, cables have been the main way to induct electromagnetic interference.Shielded cable is extensively used in communication networks and communication systems on the warship to avoid interference of outward electromagnetic energy. However, in some cases such as HEMP, thunder environment or pulse generated by high power electronic weapons, cables are inevitably impacted by high power pulse. Most of the direct coupled transient current only flows through the outer shield layer, rather than the inner conductor of cable. However, the outward energy of electromagnetic interference can still couple into the inner core through the transfer impedance and transfer admittance of the shield conductor, with the limitation of the cable shield layer structure and shielding effectiveness. The transient induct current and voltage through the inner core can reduce the performance of electronic devices and circuits, and even completely destroy the sensitive electronic equipments. Therefore, it is necessary to predict the coupling effects between the external electromagnetic interference pulse and cables. At the same time, there is a very significant coupling effect between the multi-conductor transmission lines, and the crosstalk noise can also consumedly reduce the performance of the system. Therefore, it is also necessary to accurately analysis the conduction coupling effects between the multi-conductor transmission lines.As the transmission line model can give the solution to meet the accuracy of the engineering demands, this paper mainly uses this method to analyze the crosstalk coupling effects between the cables, and the coupling mechanism between field and transmission lines. During this paper, we mainly analyze the following problems:1. Extract the per-unit-length (PUL) parameters of the multi-conductor transmission lines using the method of moments (MOM) techniques;2. Numerically simulate the crosstalk coupling effects between the multi-conductor transmission lines, including the crosstalk responses of near-end and far-end through the FDTD method;3. Research the crosstalk phenomena including near-far and far-end, illuminated by external electromagnetic field; mainly research the cases about shielded cables, and then investigate the inner core responses through the transfer impedance of the shielded cable;4. Research the responses of the transmission lines in a shielded metallic enclosure or cabin under the influence of outward transient electromagnetic environment.