A Wideband Endfire Antenna Incorporating Modified Antipodal Vivaldi Resonator and Spoof Surface Plasmon Polaritons

A wideband endfire antenna based on a modified antipodal Vivaldi radiator and spoof surface plasmon polaritons (SSPPs) is demonstrated. In the antenna structure, a double-layer SSPP transmission line with periodically etched arc slots and optimized transitions is introduced in a modified antipodal Vivaldi radiator to realize a wideband high-efficiency endfire radiation. To validate the proposed design, the SSPP endfire antenna prototype is fabricated and measured. The experimental results confirmed the simulations, showing that the antenna has good endfire radiation performances with
S
₁₁
< −10 dB and an average efficiency of 95.9% across the wide frequency range from 3 to 13 GHz. The maximum realized gain is 9.13 dBi at 11 GHz and the average realized gain is 7.2 dBi. This work may inspire new ideas for SSPPs endfire antenna design and potential wireless communication applications.