Research And Design Of Terahertz Corrugated Horn Antennas

Terahertz wave refers to the electromagnetic wave with frequency between 0.1 THz and 10 THz.The good resolution,safety and broadband characteristics make it have wide application fields and good application prospects.With the breakthrough of processing technology and the improvement of accuracy,the traditional antenna has been able to work effectively in terahertz frequency band,Terahertz antenna test is a necessary technology in terahertz antenna design.The compact field is an important technology for the millimeter wave antenna test,the compact field system is mainly composed of two parts: compact field antenna and microwave darkroom,the antenna part is mainly composed of two parts: feed and reflector.Corrugated horn antenna not only has symmetry radiation pattern,but also has a series of advantages,for instance,low side–lobe level?low cross polarization level?high stability of phase center and wide frequency band,so it is widely used as an antenna feed of high-performance reflector antenna.The main contents of this paper include the following parts:In order to meet the testing needs of the terahertz antenna,based on the requirements of the terahertz compact field for the feed,the conical corrugated horn antenna was the research and design object in this paper.Firstly,the background,significance and development status of the terahertz technology and the corrugated horn antenna were introduced.Then,there were an analysis to the working principle of the compact field and the reflector antenna,the common structure of the corrugated horn antenna.After that,some related field distribution characteristics of corrugated horn antenna were studied and some common design parameters of corrugated horn antenna were proposed,Such as frequency and bandwidth,input and output aperture,slot width ratio and groove depth,and various curve profiles,the specific selection criteria and calculation methods were given.What's more,the design method some necessary parts of corrugated horn antenna were summarized like the mode converter,the rectangular-circular waveguide transition device.Based on the above work,six kinds of terahertz corrugated horn antennas were designed,including an axial slotting structure,three radial slotting structures and two hybrid slotting structures,the detailed parameter calculation method and the whole antenna model was shown.The center frequency of the design was 260.4GHz,the frequency band was 217~330GHz,and the gain was above 12 dB.Using the electromagnetic finite element method,all the simulation results of the antenna models such as symmetry radiation pattern,VSWR,side–lobe level and cross polarization level were expected to reach the design requirement,we made a comparison among the antennas with different structures and analyzed their advantages and disadvantages.Finally,the main word of this paper were summarized,in view of the shortcomings and further research and improvement,the future work was prospected,the future work was put forward.