A novel methodology for the fast design of ultra-wide broadband antennas

A novel approach for the fast evaluation of the performance of a loaded antenna exploiting the scattering matrix properties is presented. Starting from the scattering matrix calculated by using a generic full-wave solver, it is shown how to obtain the frequency response of the antenna loaded with lumped series/parallel RLC elements, properly applying short/open circuits, without recurring to repetitive and time consuming full-wave simulations. The procedure is also able to evaluate the power dissipated on the resistive elements and hence the overall efficiency of the loaded antenna. As an example of the usefulness and reliability of the proposed approach, this fast solver has been used in conjunction with a genetic algorithm (GA) for synthesizing a loaded wideband antenna with a 20:1 bandwidth.