An efficient recursive procedure for evaluating the impedance matrix of linear and planar fractal arrays

The self-similar geometrical properties of fractal arrays are exploited in this paper to develop fast recursive algorithms for efficient evaluation of the associated impedance matrices as well as driving point impedances. The methodology is demonstrated by considering two types of uniformly excited fractal arrays consisting of side-by-side half-wave dipole antenna elements. These examples include a triadic Cantor linear fractal array and a Sierpinski carpet planar fractal array. This class of self-similar antenna arrays become significantly large at higher order stages of growth and utilization of fractal analysis allows the impedance matrix, and hence the driving point impedances, to be obtained much more efficiently than would be possible using conventional analysis techniques.