Wave pattern of a buried leaky coaxial cable in a guiding radar system

Leaky coaxial cables have been generating increasing interest as a tools of intrusion detection in guided radar systems. The radiation properties of leaky coaxial cables were investigated in a number of works, but in most of them only the open installation of the cable was considered. It is known that the radiation pattern of the buried cable differs essentially from that in the open installation. This is caused mainly by the losses in the Earth, inhomogeneities, and the presence of the Earth-air interface. In such situations the exact theoretical analysis of the radiation properties of the cable is very complicated. That is why in this work we report some results of experimental investigations of the near field radiation pattern. In the experiments we used a loop of the leaky coaxial cable buried at a depth of 10-15 cm. The length of the cable is equal to 144 m. The carrier frequency is 40 MHz.