Miniaturized Antenna Based On Spoof Surface Plasmon Polaritons

Spoof surface plasmon polaritons(SSPPs)are surface electromagnetic modes that are transmitted on metal surface structures,and have long been widely used in transmission lines,microwave devices and antennas,where are based on traveling-wave transmission theory.However,the study of introducing SSPPs as a resonant structure into a standing wave antenna has not been reported.Based on this,this paper expands the research on antennas based on SSPPs structure,and studies and designs three kinds of standing-wave antennas based on SSPPs.Compared with the corresponding traditional antenna structure,they have the advantages of significant miniaturization and easy of integration.The main research contents and innovations of this paper are as follows:1.The relationships between the unit tooth length h of the SSPPs transmission line and the phase constant ? of the SSPPs mode are discussed.Based on this,a novel dipole antenna based on SSPPs with a working frequency of 2.4 GHz is designed.And the input impedances of the two resonant modes(odd-and even-resonance modes)of the SSPPs dipole antennas are analyzed,then the corresponding universal feed structures are designed.Compared with each mode of the conventional dipole antennas,the antenna gains of the SSPPs dipole antennas are basically unchanged,and the lengths of the odd-and even-resonance modes antennas are reduced by about 24% and 33.5%,respectively.In this paper,half-wave,full-wave,3-order mode and 4-order mode of the SSPPs dipole antennas are selected for processing and testing.The measured results and simulation results are in good agreement,which verify the performance of the designed SSPPs antennas.2.A new Yagi antenna based on SSPPs is designed with working frequency is 3 GHz.Firstly,in the case of the determined SSPPs driver,the relationships between the number and the spacing of SSPPs directors with the antenna gains are discussed,and the design of the SSPPs director module is preliminarily completed.Secondly,according to the surface-electric distribution of the SSPPs transmission line,and referring to the obtained relationships between,3 with h,a new coplanar SSPPs Yagi antenna feed structure is designed.Compared with the corresponding traditional Yagi antenna,sizes of the vibrators of the driver and the directors are reduced by 32% and 27%,respectively,and the width W and length L of the overall structure of the antenna are reduced by 0.17?0 and 0.2?0,respectively,but the antenna gain G is increased by 1.9 dB.3.Anew log-periodical antenna based on SSPPs for short-vibrator or long-vibrator feeds is designed.Firstly,the structural parameters of the log-periodical antenna are preliminarily determined working at 2?12 GHz by the relationship between the existing antenna scale factor ? and the spacing factor ?.Secondly,based on the obtained relationship with h and ?,the design of the log-periodical antenna based on SSPPs is completed by experimental simulations.Finally,compared with the traditional log-periodical antenna,the lengths of the longest symmetric-vibrator fed by the short-and the long-oscillator are reduced by about 39.4% and 34.5%,and the structure of the antenna is more compact.Simultaneously,the gains of the antennas are substantially maintained.