Optimum Design of Twin Polygonal Loop Antenna Array for UHF Applications

Yagi antennas are preferred in UHF applications. Commonly used Yagi antennas are made with simple dipole elements or they use simple circular or rectangular loop as individual elements. This paper presents optimum design of adage type antenna using twin polygonal loop structure. The antenna is optimised for maximum directive gain subject to minimum voltage standing wave ratio (VSWR). The optimizations done using Particle Swarm Optimization (PSO) and simulations done using Numerical Electromagnetics Code (NEC2). The Original NEC2 source code has been suitably modified to incorporate geometric modelling and PSO. Simulation results show that antenna array designed using proposed method has better gain characteristics compared to conventional Yagiantenna arrays.