Dielectric bead loading for control of currents on electrically long dipole antennas

Methods for the modification and control of currents on electrically long wires have been studied in order to determine the feasibility of using existing structures as efficient radiators. Such radiators would be formed from conducting surfaces present on buildings or other structures, thus providing an additional resource in concealing antennas used for wireless communication. An element composed of dielectric beads has been successfully used to modify the current distributions on electrically long wires, such that the wires radiate similarly to a much smaller element. A simple model of a composite element made up of dielectric beads is presented, and a genetic algorithm is used to design the loading of a 4λ₀ wire, such that the radiation pattern emulates that of a half-wave dipole. The simple model of the dielectric beads made it possible to run many simulations of the loaded wire using the GA. The ease with which dielectric bead loaded wires can be modeled suggests that the design of efficient radiators from existing, and more complicated, wire structures is possible.