Research On Scattering Reduction Technology Of Phased Array Antenna

The phased array antenna is an indispensable equipment on the military platform,which can exchange information with our side or detect the enemy's situation.As a special scatterer,phased array antenna is different from ordinary scatterer.In addition to the inherent structural mode scattering,it also has the secondary radiation caused by the incomplete matching of antenna unit ports,which is called antenna mode scattering.Phased array antenna is the main contributor to the total RCS of airborne platform,so how to reduce the RCS of phased array antenna and design low scattering phased array antenna while ensuring the radiation performance of phased array antenna is a practical and very important research topic.Firstly,this paper introduces the research background and significance of scattering reduction of phased array antenna,introduces the research history of antenna scattering theory in detail,and gives several existing technologies of scattering reduction of phased array antenna,such as shape stealth technology,half-mode substrate integrated waveguide technology,loading absorbing material,loading artificial electromagnetic metamaterial and array synthesis and optimization technology.Secondly,this paper describes the general theory of antenna scattering,gives the definition of radar cross section,the definition of antenna structure mode scattering and antenna mode scattering,introduces four kinds of analysis and extraction methods of antenna structure mode scattering and antenna mode scattering,and verifies with Vivaldi antenna,analyzes and compares the results of four extraction methods.It is concluded that the antenna mode scattering separation method based on the port open circuit and short circuit model is more accurate and practical.Then,using the polarized rotating surface,this paper designs a low-scattering tight coupling antenna array.The working frequency is X-band,which can realize E-plane ±60°and H-plane ±60° scanning.Both the co-polarized wave and the cross-polarized wave have the effect of monostatic RCS Reduction in the X-band when the electromagnetic wave is incident perpendicularly.Finally,the design of low scattering antenna based on phase cancellation principle is introduced.A low scattering phased array antenna is designed for the case of normal incidence and 30° oblique incidence of electromagnetic wave,respectively.The working frequency range is 6-18 GHz.The main purpose is to reduce the scattering in X-band.The low scattering antenna array in the case of oblique incidence of electromagnetic waves has been experimentally verified.The simulation results and experimental results show that the RCS reduction method based on the phase cancellation principle is effective and feasible.