Research On RCS Reduction Of Airborne Antenna And Antenna Array

With the rapid improvement of aircraft stealth ability,the corresponding airborne antenna’s stealth indicators are also increasing.Therefore,the research on RCS reduction of airborne antennas and antenna arrays becomes more and more important.This article focus on the stealth techniques of three common types of onboard antennas,including Vivaldi antennas and their arrays,horn antennas,and blade antennas.The specific research contents include:First of all,it mainly introduces the definition of airborne antennas and the classification of airborne antennas,it can help us to learn about airborne antennas.Then is the theory of antenna scattering,which are the basis of our research on the reduction of airborne antenna and its array RCS.Secondly,the main analysis of Vivaldi antenna and its array RCS reduction method.Firstly,the radiation and scattering characteristics of the two-layer and three-layer Vivaldi antennas are analyzed;secondly,the influence of the parameters of the antenna dielectric substrate on the radiation performance and the scattering performance of the antenna is analyzed;then we do perforation on the side of Vivaldi antenna’s non radiation edge,analog magnetic ring,the surface scattering current will bound in the ring so as to reduce the antenna RCS;the last analysis of two-dimensional face array compared to one-dimensional linear array where are the difficulties of RCS reduction.The effect of array spacing on RCS of antenna array is analyzed.The length of Vivaldi antenna unit is changed by a quarter wavelength,the antenna units with different lengths are grouped into groups,and the array antenna RCS is reduced by the coherent cancellation of the scattered wave and the secondary scattered wave.Then,mainly for horn antenna RCS analysis.The idea of reducing the RCS by bent the feed waveguide of the horn antenna is proposed.The radiation performance and scattering performance of the horn antennas with different bending amplitudes were compared.The results show that the bending horn antenna feed waveguide can reduce the RCS within a certain angle of the nose cone direction without affecting the antenna radiation performance.Finally,an airborne balde antenna with low RCS is designed according to the requirements of the project specifications.The antenna works at 300 MHz ~ 720 MHz.The radiation and scattering characteristics of the antenna are simulated and tested,and ultimately meet the design requirements of the basic indicators,then passed the acceptance test.