Research On Filter Antenna And Power Divider Based On Spoof Surface Plasmon Polaritons

The surface plasmon has excellent properties such as wavelength compression,near-field enhancement and high frequency cutoff.In microwave and terahertz band,spoof surface plasmon polaritons(SSPPs)waveguides etched with periodic grooves or holes also support surface wave transmission.Because of its unique advantages,SSPPs waveguides have been widely used in nanometer optics,signal detection,integrated circuits and other fields.With the abundant application of wireless system and the arrival of age of big data,the miniaturization and integration of RF front-end devices have become an important development trend.A filter antenna based on SSPPs and a miniaturized power divider based on spoof surface plasmon polaritons-coplanar waveguide are designed.The main research contents and contributions are summarized as follows:1.A filter antenna based on spoof surface plasmon polaritons is designed.The Bragg reflection phenomenon on the surface of SSPPs transmission line is analyzed theoretically.By adjusting the period length of the unit,the specific frequency of surface wave can be guided,blocked or radiated.According to this characteristic,an X-band filter antenna is designed.The antenna has the advantages of high gain,low profile,tunable frequency band and high integration,so that it has a wide range of practical use scenarios.Moreover,the antenna has good radiation and filtering characteristics,the maximum gain can reach 13.6 d Bi,and the stopband S11 is above-1 d B.By adjusting the structural parameters,the maximum bandwidth can be about 1100 MHz and the minimum bandwidth can be 120 MHz.On the basis of great simulation results,a prototype of the filter antenna was fabricated and measured.The highly consistent between simulated and measured results validates the design conception.2.By introducing coplanar waveguide with defected ground structure(DGS),a compact transmission line unit structure based on SSPPs and a miniaturized 3 d B power divider based on spoof surface plasmon polaritons-coplanar waveguide are designed.The linewidth of the power divider can be reduced by 20%.Compared with the traditional dividers based on spoof surface plasmon polaritons,its low-frequency transmission characteristics are significantly improved.