Multiobjective Particle Swarm Optimization to Design a Time-Delay Equalizer Metasurface for an Electromagnetic Band-Gap Resonator Antenna

This letter presents an efficient particle swarm optimization (PSO) algorithm developed to design a near-field time-delay equalizer metasurface (TDEM) for the purpose of improving directivity and radiation patterns of classical electromagnetic band-gap resonator antennas. Triple layers of conductive printed patterns in the metasurface were optimized by the PSO algorithm to systematically design the TDEM. Predicted and measured results show a significant improvement in antenna performance including 9.6 dB enhancement in antenna directivity, lower sidelobes, and higher gain. The measured directivity of the prototype is 21 dBi, and 3-dB bandwidth is 11.8%.