On A Ku-band Cylindrical Conformal Array Antenna And Low-profile Broad-beam Antenna

The Ku-band cylindrical conformal array antenna and low-profile wide-beam antenna are studied in this thesis with the scientific research project.The contents can be summarized as follows:Firstly,the related concepts used in this paper are introduced,the research status and existing problems of related contents in this paper are expounded,the background and significance of the selected topic are explained,and the related basic theories used in this paper are also discussed.Secondly,Ku-band cylindrical conformal array antenna and low-profile wide-beam antenna are studied.The specific research work includes two parts:?1?Ku-band cylindrical conformal array antennaAccording to the engineering requirements of Ku-band cylindrical conformal array antenna,two design schemes of cylindrical conformal array antenna are analyzed and presented.In the first scheme,32 microstrip radiating elements are uniformly and conformally arranged in a designated area on the surface of a cylinder with a diameter of7.25?₀ to form a conformal array antenna,and a 1-to-32 stripline power divider is used as the feeding network.Based on this design scheme,the cylindrical conformal array antenna is modeled and simulated by the simulation software HFSS.The simulation results show that this design scheme for the conformal array antenna fails to achieve the requirement that the gain should not be less than-2dBi within the required beam coverage range.The second scheme is improved based on the first scheme by replacing all 32 microstrip radiating elements in the cylindrical conformal array antenna with microstrip quasi-yagi antennas.The simulation software HFSS is used to model and simulate the microstrip quasi-yagi cylindrical conformal array antenna.The simulation results show that this improved design scheme realizes the beam tilt of the cylindrical conformal array antenna in a specific direction and meets the requirement of the beam coverage range.Based on the model of the microstrip quasi-yagi cylindrical conformal array antenna obtained by simulation optimization,the antenna prototype is fabricated and measured.The measured results are in good agreement with the simulation results and show that in the operating frequency band of 14.5GHz±200MHz,the gain of the cylindrical conformal array antenna in the specified beam coverage range is greater than-2dBi,which proves that the design scheme can be applied to engineering application.?2?Ku-band low profile broad beam antennaAccording to the technical requirements of low profile broad beam antenna,the design scheme of SIW cavity-backed magneto-electric dipole antenna is presented.The scheme is based on the theory of magneto-electric dipole antenna and of substrate integrated waveguide resonant cavity.Rectangular slot is utilized on the circular substrate integrated waveguide?SIW?resonant cavity,which are equivalent to magnetic dipole when working.A half-wavelength metal strip is placed orthogonally to that slot as an electric dipole to form a magneto-electric dipole antenna.Electric dipoles and magnetic dipoles are complementary antennas and when they are excited at the same time,unidirectional wide beam radiation pattern can be obtained.As SIW resonant cavity is adopted in this design instead of reflecting plate or metal reflecting cavity,low profile characteristics is realized.The simulation software HFSS is used to model and simulate the antenna in the design scheme.The simulation results show that with a low profile,broad beam radiation patterns of more than 150°in E plane in the working frequency band of 14.5±0.1GHz are realized.According to the simulation model,an antenna prototype is fabricated and measured.The measured results are in good agreement with the simulation results.The low-profile and wide-beam characteristics of the Ku-band antenna prototype are realized.Finally,the research work is summarized and the problems needed further research are given.