Electromagnetic Scattering Characteristics Of Random Media Based On Non-Intrusive Polynomial Chaos

The plasma is a special medium composed of ions,electrons and unionized neutral particles.In reality,plasma usually shows uncertainty due to random electromagnetic parameters,which is called random plasma.It is of great significance to study random plasma especially its electromagnetic scattering characteristics.In this paper,the Radar Cross Section(RCS)of random plasma coated target is studied based on Non-intrusive polynomial chaos(NIPC).In addition,a hybrid Monte Carlo/polynomial chaos expansion method is proposed in view of the shortcoming that the number of expansion items increases exponentially when NIPC methods is applied to multiple random variable problems.The specific work of this paper is as follows:(1)The Non-intrusive polynomial chaos expansion method based on point configuration is applied to study the electromagnetic properties of random plasma.The statistical properties of the radar cross section of the metal target coated by random plasma are calculated.Compared with the intrusive polynomial chaos method and the Monte Carlo method,the accuracy and effectiveness of the algorithm are verified.(2)The hybrid Monte Carlo/Non-Intrusive polynomial chaos(MC/NIPC)method is proposed,combining low-order non-intrusive polynomial chaos method with a small amount of Monte Carlo,The uncertainty analysis of multilayer random plasma overlying two-dimensional metal cylinder RCS is carried out.Compared with Monte Carlo results,the correctness of the proposed algorithm is verified.The results show that the algorithm not only avoids the shortcoming of large number of numerical simulations,but also alleviates the problem of the number of expansion terms increases exponentially when the random variables increase.(3)The hybrid Monte Carlo/Non-Intrusive polynomial chaos method is applied to the electron density model of time-varying plasma,and the statistical characteristics of the transmission coefficient(including mean value and standard deviation)after plane wave propagation in non-uniformly layered random plasma.Compared with large number of numerical simulation MC methods,the hybrid MC/NIPC method can greatly reduce the simulation time and computational cost,the efficiency of the proposed algorithm is verified.