Comprehensive Comparison of Compact UWB Antenna Performance by Means of Multiobjective Optimization

An optimization-based procedure for comprehensive performance comparison of alternative compact UWB antenna topologies is discussed. The assessment of the antenna performance is conducted with respect to the structure size and its reflection response. More specifically, the best possible tradeoffs between these two figures of merit are identified through multiobjective optimization at the level of full-wave electromagnetic (EM) simulation. Analysis of Pareto-optimal designs obtained for various antenna topologies allow for their fair comparison; particularly in terms of the minimum size, they can be designed for (assuming acceptable reflection response levels) or the best attainable reflection characteristics. For the sake of computational efficiency, the multiobjective optimization algorithm utilized in this paper exploits sequential domain patching technique and variable-fidelity EM simulation models, which is a fully automated procedure that permits finding Pareto set representations at the cost corresponding to about a hundred of high-fidelity EM analyses of a given structure. The proposed approach is demonstrated using three topologies of compact UWB-monopole antennas. Comparison of antenna with respect to three objectives (also including total efficiency) is also discussed. Simulation results are verified using experimental data.