| Leaky Coaxial Cable (LCX) is a kind of special cables that people deliberately open aseries of slots, holes on the ordinary coaxial cable outer conductor. Electromagnetic energycould transmit along the cables axial as well as leak through the slot to the outer space, so thesurrounding space of the cable could obtain electromagnetic signals, at the same time theouter space energy can be coupled into the LCX. So it can be used as a transmission line andalso a radiating antenna. LCX is widely used in some closed field or semi-enclosed domainspace where radio waves difficultly or poorly propagated to solve the problem of thecommunication blind zone.Firstly, this paper beginning with the basic theory of LCX, described the physicalstructure and the classification of the LCX, introduced three major electrical performanceindicators: operation frequency band, coupling loss, transmission loss and a number of factorsaffecting the three indicators. Radiation theory is analyzed such as radiation principle,radiation pattern and radiation angle. And this paper also discussed how to expand the singlemode radiation band of LCX. This part paved the way for the following simulation analysis ofLCX.Secondly, the HFSS software is used to analyze the radiation characteristics and couplingcharacteristics of the LCX with different arrangement outer conductor opened slots. Thedifferent slotted spacing LCX model is constructed, the radiation pattern and the internalelectric field distribution are obtained. The correctness of the simulation is verified for theradiation direction angle obtained from the simulation is consistent with theoreticalcalculation. According to the theory of expend single mode radiation band, a vertical andcharacter type LCX model are established, two types of LCX band extension and couplingwith the increase of the slotted number are analyzed.Finally, part of the focus of this paper, on the basis of understanding the theory ofelectromagnetic pulse, CST simulation software is used for analysis of how LCX respondwhen Gaussian pulses with different parameters illuminating, and also analyzed couplingcharacteristics of the UWB pulses on the LCX with different hole size, hole spacing, numberof holes. The coupling characteristics of the electromagnetic pulse on the LCX is qualitatively analyzed, providing a reference for designing the LCX to avoid electromagnetic pulse damage,at the same time laying a foundation to study the characteristics of the LCX in a complexelectromagnetic environment. |
