Genetic Algorithms and Method of Moments for the Design of Pifas

This paper presents a novel technique for efficiently combining genetic algorithms (GA's) with method of moments (MOM) for planar inverted-F antennas (PIFAs). MOM is applied to analyze rectangular patches fed by a coaxial probe and shorted with a shorted pin. The impedance matrix of such a mother structure is, then manipulated by a GA optimization procedure in order to detect the optimal patch shape matching the required frequency properties. GA adoption enables optimal shape detection among all possible shapes allowed by the mother structure dimensions. The design example of dual-band antenna is presented, and measurement result is compared to numerical results. Excellent agreement between numerical and measured results is observed.