Design of Small Parasitic Loaded Superdirective End-Fire Antenna Arrays

This paper presents an approach for designing parasitic loaded superdirective antenna arrays. The array current excitation coefficients calculated based on Yaghjian method are used with the array input impedance matrix to deduce the required loads for transforming the array to a parasitic one. The proposed method´s practical limitations are studied via a parametric analysis on dipole-based arrays. It is also applied to design two- and three-element arrays based on an electrically small antenna (ESA). Simulation results show a very good agreement between the fully driven array´s total directivity radiation pattern and the parasitic (loaded) array´s one. Simulation results also show that the array end-fire total directivity is maximal at the design frequency. Measured results are in a very good agreement with the simulated ones.