Lumped element networks for replacing sections of a buried transmission line

A buried transmission line formed by vertical conductors can function as a wave guiding structure in producing a part of the electromagnetic field distribution caused by a distributed source at the air-earth interface. Such a structure, when excited by an appropriate low-frequency source, is a viable EMP simulation technique for use with underground systems. In the developmental phase of such a technology, there exists a need to artificially elongate the buried line by using lumped element networks. In effect, such networks simulate the simulator plates and earth. The authors address such a network concept and its design considerations. The actual design, fabrication, and testing of an example network are also presented.<>