Analysis and design of tapered slot antenna with high gain for ultra-wideband based on optimisation of the metamaterial unit layout

To further develop the advantages of loading artificial material units, layout rules of unit cells were investigated and presented for the first time in this study. Based on the analysis of transmission characters of metamaterial unit cells, some tapered slot antennas loaded with different unit layouts were designed. The result comparison showed that after the layout optimisation, the operation frequency band with a gain above 10 dB increased by about 13% and the gain increased by 0.4–2.6 dB in the high frequency band. In addition, the sidelobe level of H-plane also decreased by 0.7–4 dB at different frequency points.