Study On Miniaturized Antenna Based On Spoof Surface Plasmon Polaritons

With the rapid development of electronic technology,the electronic countermeasures technology becomes more and more important in national defense forces.Due to the expansion of the bandwidths of radar systems and the demand for high integration and multi-channel,the requirements of high gain,broadband and miniaturization for antennas also increase.Spoof surface plasmon polaritons(SSPPs)are a special surface slow wave with extraordinary field confinements and sub-wavelength characteristics and also have the characteristics of low profile,conformal and can be combined with traditional RF devices,which plays an important role in the antenna design field.In this paper,SSPPs are applied to the design of helical antenna for the first time,and the miniaturization of helical antenna is studied deeply.The main work is summarized as follows:1.A broadband axial-mode helical antenna is designed.Microstrip matching section is used to achieve the optimal matching of the antenna.The influence of the geometric parameters of the helical antenna on the radiation performance of the antenna is simulated and analyzed.Based on the simulation results of the geometric parameters of the antenna,a broadband axial-mode helical antenna with a center frequency of 4 GHz is designed.The final structure was fabricated and tested.The relative bandwidth of the measured antenna reached 36.7% and the maximum gain is 10.5 d Bi.The antenna has the characteristics of broadband,high gain,good circular polarization performance and easy tuning.2.A SSPP axial-mode helical antenna is designed.According to the dispersion characteristics of SSPPs,the SSPP axial-mode helical antenna with the same center frequency as the traditional axial-mode helical antenna is designed.Because the SSPPs have a larger propagation wave vector at the same frequency point,the antenna miniaturization is realized.An axial-mode SSPP helical antenna with a center frequency of 4 GHz is proposed.The effects of groove angle and phase velocity of SSPP unit on antenna radiation are analyzed.Compared with the traditional axial-mode helical antenna,the length of metal strip is reduced by 20%,the physical aperture is reduced by 36%,the height is reduced by 20%,and the volume is reduced by 49%,so the miniaturization effect is obvious.The proposed SSPP axial-mode helical antenna has a great application prospects in the background where minimization for antennas is increasingly demanding.