Lu Shu

SCTE: RCS Prediction System for Complex Target and Interaction with Environment

A RCS prediction system named SCTE (Scattering from Complex Target and Environment) for calculating high-frequency electromagnetic scattering from complex target within complex environment is presented. The scattering body is described by Computer-Aided-Design (CAD) representations in which the complex body is modeled as NURBS (Non-Uniform Rational B-spline) surfaces. The complex environment (rough surface of sea or ground) is also carefully considered by using fractal function. Scattering fields are calculated by using physical optics and the equivalent currents methods. There is a good agreement between the present results and that from measurements which demonstrates the accuracy of this system.

Scattering of complex target within complex environment

This paper presents an RCS prediction system for calculating high-frequency electromagnetic scattering from complex target within complex environment. The scattering body is described by computer-aided-design (CAD) representations in which the complex body is modeled as NURBS surfaces (Non-Uniform Rational B-spline). The complex environment (rough surface of sea or ground) is also carefully considered by using fractal function. Scattering fields are calculated by using physical optics (PO) and the equivalent currents methods (MEC). There is a good agreement between the present results and that from measurements which demonstrates the accuracy of this system.

EM scattering by rectangular conducting flat plates with thin uniaxial anisotropic materials

In this paper, according to the equivalence principles, high frequency approximation and boundary conditions, a method has been developed to deal with the EM scattering by a rectangular conducting flat plate coated with uniaxial anisotropic radar absorbing material (RAM). The simple but effective method is available to the system of RCS prediction in which the large complex targets are modeled by facets and wedges. Numerical results show some properties of EM scattering by conducting plate coated with thin uniaxial anisotropic RAM.

Analyzing the Scattering Near-Field from Complex Targets

This paper presents a theory method to calculate and analyze the scattering near field from some simple and complex targets, using high-frequency approximation. By calculating the near-field RCS of some simple and complex targets based on the SCTE (scattering from complex targets and environments) system, the results show that there are much difference between the near field and the far field. And the characteristics of the near field are more complicated. This method has practical engineering value in the area of the electromagnetic interference (EMI) prediction and electromagnetic scattering (EMS) et al

Analysis of EM Scattering by Electrically Large Coated Object

The high-frequency method in conjunction with impedance boundary condition is one of effective tools in analyze the far or near field of EM scattering by electrically large coated object. The far field RCS of coated plate calculated in the paper shows agreement with experimental results , and the differences between near field RCS and the far field RCS concludes that the near field scattering must be taken into account while using coating stealthy technology for electrically large object. In addition, the RCS of XX ship coated with four kinds of RAM is given in the paper

Study on the EM scattering of rivets on the plate

The electromagnetic (EM) scattering by rivets on the conducting plate is studied for the first time by using electric field integral equation (EFIE) in conjunction with the moment method. The surfaces of the rivets and the plate are partitioned into triangular cells, the current distribution on the patches is represented by sub-domain type basis function, the EFIE is translated into matrix equation by the Galerkin method, then the current coefficient is obtained. The results show the properties of radar cross section (RCS) varying with the incident angle when there are rivets on the plate.

The reflection and transmission of electromagnetic wave from small particle-dielectric composites sheet

The electromagnetic properties of composites which are made of small particles imbedded in an insulating matrix have been studied. The electromagnetic fields inside and outside the sphere particles were derived using Mie theory, and the renormalized permittivity and permeability that take into account effect of retardation were introduced. When the skin effect in metal is strong by high frequency electromagnetic field under conditions for the metal-dielectric composites, the developed effective medium theory (DEMT) is more suited than the effective medium theory (EMT) to describe the properties of composites. Numerical results exhibit the characteristics of reflection and transmission of electromagnetic waves at composite sheets.

EM Scattering from conducting flat plates coated with thin RAM

According to the equivalence principles, high frequency approximation and boundary conditions, a method has been developed to deal with the EM scattering by a rectangular conducting flat plate coated with uniaxial anisotropic radar absorbing material (RAM). The simple and effective method is available to the system of RCS prediction in which the large complex targets modeled by facets and wedges. Numerical results show some properties of EM scattering by conducting plate coated with thin uniaxial anisotropic RAM.

A study on composite scattering of targets and environment

An analysis of the composite scattering between the target and the environment is made. The two-dimensionally fractal function is used to model the rough surface, and the scattered electromagnetic field is calculated by using Kirchhoffs approximation. The validity of the result is assured by some reference, which indicates that the methods in this paper are reliable, then a simple and practical example is given.

A study of propagation in Shenzhen city

Surveying the propagation path loss behavior of Shenzhen city and from the data recorded we can obtain the city’s path loss slopes, which can be comparatively regarded as the reliable bases of system design.