Calculation and evaluation of electromagnetic scattering characteristics of targets with uncertain parameters

Aimed at the current situation of incomplete information on non-cooperative targets and uncertainties in target geometry and material properties due to manufacturing processes, environmental factors, human factors, etc., the method of analyzing the electromagnetic scattering characteristics of uncertain targets based on Taylor series expansion is presented. The nonuniform rational B-spline surface(NURBS) modelling technology is used to construct arbitrary shaped targets. The target shape parameter and dielectric parameter extraction techniques are used to establish the functional relationship between the target geometric shape/dielectric parameter and the electromagnetic integral equation of the method of moments. From this, the amount of current change due to changes in shape and medium is calculated, and then the electromagnetic scattering characteristics of metal/medium/mixed targets are analyzed when random variables are introduced into the geometric shape and medium. Secondly, this paper proposes a technique for analyzing the electromagnetic scattering characteristics of uncertain high-dimensional targets based on the asymptotic waveform evaluation(AWE) method. It extends the asymptotic waveform estimation technique to encompass the analysis of target shape and dielectric constant uncertainty. Calculating the derivatives of each order using the pseudo-spectral method can significantly reduce derivation and computation time, as compared to deriving formulae. The Padé approximation is employed by this technique to determine the final current following a change in the target. Additionally, it has the ability to precisely compute a greater degree of random perturbation in contrast to methods relying on Taylor series expansions. Compared to the Monte Carlo (MC) method, the approach presented in this paper greatly enhances the overall computational efficiency. Simulated and measured results are in agreement. Finally, a backpropagation neural network is utilized to achieve intelligent calculation of confidence and uncertainty regarding the scattering characteristics of uncertain targets. It is demonstrated that the proposed method provides an accurate and effective analysis of the high-dimensional uncertainty problem pertaining to non-cooperative targets, thereby substantially enhancing computational efficiency.