Research On The Design Of Radiation And Scattering Balance Of Airborne Radar Antenna

As the most efficient and wide-ranging detection device today,radar plays an important role in interacting with friendly information and probing enemy intelligence on military platforms.With the continuous development and updating of modern radar systems,stealth technology is used to counter the detection and accurate targeting of flying targets by enemy radar systems is brought to a high strategic level,and how to reduce the RCS(radar scattering cross section)of aircraft and make enemy radar "blind" is an important goal of stealth technology research.In this thesis,we study how to optimize the scattering performance of the antenna while ensuring the normal operation of the antenna,and how to achieve a balanced design of radiation and scattering from the stealth technology,specifically from the airborne array antenna,which is a strong scattering source and one of the main sources of RCS of the aircraft.Firstly,this paper introduces the background and importance of airborne radar antenna radiation and scattering research,introduces the development status of antenna scattering theory at home and abroad,selects the Vivaldi antenna with low RCS characteristics according to the subject needs,and introduces several existing RCS reduction means as an example,including antenna shaping or slotting,absorbing material coating,substrate integrated waveguide loading,metamaterial structure application.The advantages and disadvantages of different means are analyzed.Then,this thesis specifies the radiation principle of Vivaldi antenna,the basic principle of antenna scattering,gives the physical meaning of RCS,and introduces the scattering composition of antenna contains mode term scattering and structural scattering.Then,the Vivaldi antenna is selected as the array unit according to the technical index,and the scattering performance of the antenna is optimized by selecting the absorbing material coating,antenna shaping and slotting,and creating phase difference to make the mode term scattering to cancel,etc.under the condition of meeting the radiation condition,and the 8×8 antenna array is formed to realize the beam scanning capability of ±45° in E-plane and ±52° in H-plane.After that,the theoretical analysis is carried out according to the different scattering formed by the obstacles during the electromagnetic wave propagation,and the carrier design idea is determined to ensure the carrier has low scattering characteristics.Then the carrier is slotted according to the size of the antenna array and the installation environment,and the influence of different slotting shapes,slotting depth and absorbing material application on the RCS of the compartment is discussed in the process,and it is found that the carrier digging a shallow slot with a rounded transition to the surface and an inclined array surface is the optimal slotting scheme.After obtaining the low scattering compartment,the 108-cell antenna array is put into it for integrated simulation,and the scattering performance of the array is obtained.Finally,considering the cost factor,based on the existing simulation results,processing small antenna arrays with small carriers for physical testing,the test results show that the airborne radar antenna in the case of normal radiation work also has low RCS characteristics.