Optimization of Gain, Input Impedance and Bandwidth of Yagi-Uda Antenna Arrays using Hybrid Genetic Algorithms Engineering

Abstract

This paper tries to compare the gain, input impedance, Zin, and bandwidth characteristics of five-element nu-dipole Yagi-Uda antenna and that of five-element vee-dipole Yagi-Uda antenna. A combination of method of moment (MOM) and Genetic Algorithm (GA) was used to maximize directive gain as a single objective function for both antenna arrays and directive gain and input impedance of (12.31dB and Zin=8.46+j27.08 Ω) and (12.14dB and Zin=9.04+j1.03 Ω) were obtained for nu-dipole array and vee-dipole array, respectively. Composite objective function comprising of directive gain with input impedance, Zin≈50Ω, produced values of (9.98dB and Zin=50.39+j0.42 Ω) and (10.66dB and Zin=49.14-j1.64 Ω) for the nu-dipole and vee-dipole arrays, respectively.