Research On The Novel Cpw-based Spoof Surface Plasmon Polaritons And Its Components

Spoof Surface Plasmon Polaritons(SSPPs)are the electromagnetic waves with high field constraints and non-diffraction limits that can propagate along textured conductive surfaces in the deep subwavelength range.With the rapid development of science and technology,SSPPs plays an increasingly important role in the new generation of photoelectric integration technology,photoelectric abnormal transmission,biological detection,photon clustering effect,high-precision imaging,high-sensitivity detection and biological medical fields.SSPP structures with high integration,miniaturization,and high performance are the research hotspots in the field of microwave and physics.In this thesis,a new SSPPs is proposed and the dissertation focuses on the research and development of SSPPs working mechanism.Based on this SSPPs,we have designed a series of components.It is organized as follows:Chapter one mainly focuses on the miniaturized coplanar waveguide filter based on the spoof surface plasmon polaritons with high performance.By using the periodic holes etched on the standard 50-?CPW metal strip-lines,which not only has a high-efficiency low-pass transmission but also realizes a controllable multi-band performance.More importantly,the proposed structure integrates the mode conversion structures and mode transmision function in the CPW waveguide filter,leading to a characteristic of miniaturization.The proposed SSPPs not only remove out the gradual structures for mode conversion,but also has high low-pass transmission efficiency.The proposed SSPPs can achieve a controllable multi-band performance by controlling the length of the unit cell.Chapter two mainly focuses on a band-pass filter based on the novel spoof surface plasmon polaritons.The band-pass filter integrates with SSPP-based waveguide low-pass filter with periodic holes etched on the CPW,CPW-based coupling structure and the split ring resonators(SRRs),which achieves a high effiency band-pass transmission performance.The low and high cut-off frequencies of the band-pass structure can be independently controlled by changing different parameters,respectively.The proposed band-pass filter has low insertion loss,simple structure,and flexible design characteristics.Chapter three mainly proposed an effective way to split the SSPP wave,and based on this method,we designed the SSPP power divider and frequency splitter.Moreover,a MZ interferometer is also proposed based on the SSPP power divider.The proposed wave splitter,MZ interferometer,and frequency splitter have the high transmission efficiency,and the isolation of ports is good.These components have the compact size and low fabrication cost.Chapter four mainly focuses on wide-angle frequency beam scanning antenna and integrated hybrid antenna based on the proposed SSPPs.The frequency beam scanning antenna employs an array of holes etched on the middle line of the coplanar waveguide(CPW)to generate SSPP waves and utilizes its higher-order modes to radiate EM waves.The overall width of the proposed frequency beam scanning antenna is only 0.95?₀(with?₀ being the wavelength of the lowest working frequency)(13)The proposed frequency beam scanning antenna achieves a wide scanning angle of 129°over a frequency range from 11.7 to 50 GHz(for|S11|<-10 d B)with an average gain level of 12.38 d Bi.Moreover,based on the characteristics of the novel SSPPs,this chapter also proposes an integrated hybrid antenna with omnidirectional antenna(ODA)and the frequency beam scanning antenna(FBSA)performance.The proposed SSPPs design not only serves as the feeding structure for the ODA,but also acts as the radiating element for the FBSA.The lower operating frequency band of the proposed integrated antenna covers 2.32 GHz-4.42 GHz and achieves omnidirectional radiation pattern.The higher operating frequency band of the proposed integrated antenna is from 11.45 GHz to 25.5 GHz,which realizes a wide beam scanning angle(75°).Chapter five proposed a new method to generate localized EM vortex waves with multi-modal topological charges.Based on the characteristics of meta-particles and SSPPs,we can realize the localized PVs printing technology by using the symmetric EM field distribution of CPW-based SSPP waveguide.PVs with multi-modal topological charges(+1,0,and-1)supported by a periodic array of meta-particles can be successfully excited simultaneously.Meanwhile,physical mechanisms are explained by analyzing the dispersion curves of SSPP,resonance and coupling characteristics of single metaparticle,and power transmision characteristic of the design.The experimental results verified our proposed method and structure.