Characteristics Of The Metal Polyhedron Wire Antenna

The wireless communication technology is developed so much that more and more communication devices appear in vehicles, ships and aircrafts nowadays. How to make these devices work well in limited space? How to predict and solute the electromagnetic interference (EMI) between them? More attention is given to these problems and it became one of the most important contents in electromagnetic compatibility (EMC) research. Wire antennas are still very popular on vehicles, ships and aircrafts. They are easily to be interference sources and sensitive bodies. In our calculation we must take account of the mutual coupling between wire antennas when they are very close. In many cases vehicles, ships and aircrafts can be seen as arbitrary faceted conducting bodies. In this paper the characteristic of several wire antennas attached to an arbitrary faceted conducting body and the infection between them are analyzed.This problem requires a good description of the electromagnetic behavior of the whole body, including the coupling and junction effects between the antennas and the supporting structure. For these kinds of problems, the method of moments (MOM) is the most suitable tool due to its accuracy and versatility. Characteristic analysis of single wire antenna attached to a conducting body or plate is done in many papers but very few people pay attention to the case of several wire antennas. A deep research for several wire antennas attached to an arbitrary faceted conducting body is made in this paper. When we analyze the characteristic of several wire antennas attached to an arbitrary faceted conducting body we must divide it into two cases. One is that the conducting body is electrically small, the mutual coupling and infection between the antennas and conducting body are very obvious. So we must model them precisely and the shape of the conducting body, the length and location of the antennas etc. are must be taken into account. The other is that the conducting body is electricallylarge. We can solve this case by high frequency methods or hybrid methods of high and low frequency for example the hybrid of MOM and GTD.In this paper the second case is mainly analyzed. First, geometric modeling is made. Then the integral equations derivation to characterize the radiation and scattering from several wire antennas attached to an arbitrary faceted conducting body is made. The source is simulated with a TEM magnetic current ring. The integral equations are solved and calculated in computer by MOM. So the currents on the antennas and body are got that can make us get the input impendence and radiation pattern easily. Also the suited basis and weighting functions choices are researched in this paper including the case that the antennas are mounted near an edge or a vertex. In the end some cases that several wire antennas attached to an arbitrary faceted conducting body are analyzed and calculated and some useful conclusions were get.The research in this paper is valuable to antenna and EMC design on the vehicles, ships and aircrafts etc.