Radiation Pattern Synthesis from Dielectric Rod Waveguides by Disposing Radiation Sections

A radiation pattern synthesis of dielectric rod waveguides with many radius variations is investigated. The radiation field from radius variation sections is expressed in the form of a 4-port circuit, so that the field can be calculated in short time. This expression can be used in the genetic algorithm (GA) to seek the optimum positions of radius variation sections. A conical beam with 30 deg. width can be synthesized. The experimental radiation pattern agrees with the synthesized one with small difference.