The Scattering Characteristics Of Novel Chaff And Foil

Working as a passive jammer,chaff plays an important part in the fields of air defense,anti-ship,anti-missile,etc.since the Second World War.With the development of radar technology,operating frequency of radar is becoming higher and higher and the detecting ability has been greatly enhanced which means traditional chaff no longer meets the need of interference.To solve this problem,novel chaff with high scattering properties needs to be designed.The paper analyzes scattering properties of chaff in detail,and based on this,a novel structure of chaff is designed.Moreover,the paper also gives the designing method targeted at this kind of structure.Main work of this paper can be divided into three parts.In the first part,method of moment(MoM)is used to analyze scattering properties of targets.Firstly,the paper introduces basic principles of MoM and its applications in scattering analysis of PEC targets in combination with surface integral equations.Then,some simulating examples are given which are used to verify the effectiveness of MoM.The second part contains two parts,including scattering analysis of traditional chaff and design of novel structures of millimeter wave chaff.In the former,scattering properties,surface currents,shapes and structures of half-wave chaff are studied and emphasis is laid on influence of structures to scattering properties.In the latter,a kind of stretching chaff is putted forward.Surface currents' distribution as well as scattering properties of this structure is analyzed and a novel structure which can change distribution of surface currents is designed.The third part analyzes scattering properties of foil,including scattering analysis of traditional foil and design of novel structures of millimeter wave foil.In the former,the paper introduces structures of traditional foil firstly.Then,scattering properties,polarization properties,frequency properties of traditional foil are studied with emphasis being laid on influence of shapes and acreage to scattering properties.In the latter,genetic algorithms combined with MoM is adopted to optimize structures of foil and three kinds of structures are designed under optimization.The designed structures can overcome disadvantages of traditional foil such as large size,high weight and so on.