GA-Based Design of Multi-Ring Arrays With Omnidirectional Conical Beam Pattern

The optimal design is presented of single- and multi-ring arrays with an omnidirectional conical beam by using a genetic algorithm (GA). The design parameters to be optimized are ring radii, excitation phases and amplitudes, requiring that the excitations of all elements in the same ring have the same amplitude and periodic phase for minimal azimuth-dependence in beam pattern. Parametric studies of the beam pattern were conducted and the theoretical radiation pattern was also validated from the experimental result with a single ring array antenna. As examples of GA-based design, two types of conical beam pattern were considered, illuminating a significant circular zone for satellite communications on moving vehicles. All results gave an omnidirectional conical beam pattern, in good agreement with the desired mask pattern.