| With a rapid development,the capacity of the communication system increases,the operating frequency band gets constantly higher,the shortage of spectrum resources looming,Microwave and Millimeter wave(MMW)wireless communication system becomes a hotspot of research nowadays.As a significant component of antenna system,the shape,size and performance of the antenna have an immediate impacts on the entire system of communication quality,Compared with other types of antenna,the reflector antenna found to be superior in simpler structure,lower cost and higher gain,and it's widely used in microwave and millimeter wave communication systems.Therefore,the research of the miniaturization,high gain and high cross-polar isolation of dual-polarized highperformance reflector antenna is going to be a remarkable issues.At present,the existing Ku-band reflector antenna can basically meet the requirements of ETSI Standard class2 envelope electrical performance in the far-field pattern,but it is difficult to realize the ETSI Standard class3 near-sidelobe radiation field under the condition of ensuring high gain of the antenna.In this paper,we research the reflector antenna theory based on the study of electromagnetic field and microwave theory,the principle of antenna and the calculation of electromagnetism,and with the help of electromagnetic analysis and Simulation software of HFSS and Feko,a high performance reflector antenna with a diameter of 0.3m and a center frequency of 15 GHz is designed.By shaping the dielectric supporting mirror and sub-reflector of the splash-plate feed,we realize the far field radiation pattern equalization and roll-off of E plane and H plane within and out of the scope of the main reflector irradiation angle,respectively.Then,the impedance matching of the antenna is realized by optimizing the media matching plug.Finally,the model of the reflector antenna is processed and tested,and the electrical performance analysis and parameter extraction of the antenna are completed.The simulation and test results show that the designed reflector antenna has small voltage standing wave ratio,VSWR in the whole band of not higher than1.22,the gain at the antenna center frequency point is 32.43 d Bi,the far field pattern can meet the high performance of ETSI Standard Range2 Class3 standards and other excellent performance.On the premise of the same efficiency requirements,compared with the same type of reflector antenna,it has better near-sidelobe and sidelobe suppression,Maximum sidelobe level of the center frequency suppression to 21.89 d B,and the ratio of front to back in E and H plane up to 59.57 d B.The points of this paper are as follows:1.Research on the basic theory of reflector antennas,including the geometrical model of reflector antenna,the surface current method and the aperture field method based on the physical optics and geometrical optics respectively.Focus on the effect of the aperture field distribution on the far field pattern of antenna radiation.The basic theory and analytical method of the reflector antenna provide the basis for the design of the subsequent reflector antenna2.Based on the basic theory of the reflector antenna,the basic principle,the calculation method of the radiation field,the characteristics of the feed horn and the design idea of the Cassegrain antenna are analyzed.3.In this paper,we have designed a splash-plate feed reflector antenna.And with the help of HFSS,Feko and other simulation software,a reflector antenna is designed and optimized to meet the expected performance.4.Analysis of the measurement principle and method of reflector,and the processed sample of splash-plate feed antenna model is tested and analyzed.The results show that the test results are in good agreement with the simulation results,and the design method is effective. |
PDF Full Text Request