Design Of Leaky-wave Antenna Based On Spoof Surface Plasmon Polaritons

Planar leaky-wave antenna is favored due to its low profile,easy integration and beam frequency scanning.As a new type of planar transmission line,spoof surface plasmon polaritons(SSPP)transmission line has the advantages of natural periodicity,simple feeding structure,low profile and easy regulation of electromagnetic characteristics.Starting with the periodic element of artificial surface plasmon leaky-wave antenna,this thesis designs a parameter extraction method for SSPP leaky-wave antenna and verifies its feasibility.Leakywave antennas with low sidelobe and dual-beam functions are designed respectively to improve the flexibility and accuracy in the design process of leaky-wave antenna.The main research contents of this thesis are as follows:1.A method for extracting dispersion parameters of spoof surface plasmon polaritons leakywave antenna is proposed.By redefining the calibration reference plane,the problem that it is difficult to extract directly and accurately due to the influence of feed structure in the process of parameter extraction is solved.In order to verify the accuracy of the above methods,the ideal three-dimensional SSPP transmission line and plane two-dimensional SSPP transmission line are designed,and their dispersion parameters are extracted.The extracted dispersion parameters are in good agreement with the results of theoretical calculation.2.The SSPP leaky-wave antenna based on sinusoidal surface impedance modulation is studied,and the design process of SSPP leaky-wave antenna based on sinusoidal surface impedance modulation is described in detail.Using the dispersion parameter extraction method proposed in this paper,the relationship between the physical parameters and electrical parameters of each unit is studied.Combined with the Taylor distributed array synthesis method,a low sidelobe SSPP leaky wave antenna is designed.Compared with the leaky wave antenna without low sidelobe,the sidelobe level is reduced by 6 d B.3.A SSPP dual-beam leaky-wave antenna based on dual-mode unit is proposed.By studying the dispersion characteristics of asymmetric elements,the dual beam radiation is realized.The dual-beam antenna has the characteristics that two lobes can be adjusted independently,which increases the flexibility of dual beam antenna design.The simulation results of the antenna are compared with the machining test results,and the results accorded with the simulation results well.