Broadband loaded dipole antenna design by genetic algorithm optimization

Asan, Bahri
It is well known that standard dipole antenna is not convenient to be used in broadband wireless communication applications because of its narrow frequency bandwidth. To broaden the bandwidth of a dipole, lumped loading is the generally applied method. Positive effects of resistive, capacitive and inductive loading are discussed and proved for a pretty long time. This thesis investigates broadband lumped loaded dipole antenna design procedure by using genetic algorithm optimization techniques. First, unloaded dipole antenna numerical analysis formulation is provided by EFIE (Electric Field Integral Equation) derivation. MoM (Method of Moments) is used for numerical solution. Then, analysis is extended for lumped loaded dipole antenna. Analysis computer code is developed in MATLAB environment and results are compared with NEC (Numerical Electromagnetic Code). To design loaded dipole antenna with corresponding matching network which satisfies the predefined radiation parameters, genetic algorithm (GA) optimization methods are used . GA searches for an optimal solution from random solution set with iterative methods. Optimization objectives are selected as increasing the minimum antenna gain and decreasing the maximum VSWR. Load values, positions and matching network variables are optimized simultaneously. Finally, successfully optimized broadband loaded dipole antenna and matching network design examples are presented to verify the used procedure.


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Citation Formats
B. Asan, “Broadband loaded dipole antenna design by genetic algorithm optimization,” M.S. - Master of Science, Middle East Technical University, 2014.