Research On FDTD Algorithm Of Plasma Target Based On Linux System

The FDTD algorithm is a solution to Maxwell's differential equations and is suitable for solving any electromagnetic problem.At the same time,FDTD algorithm can also be used to solve the black obstacle phenomenon that the aircraft re-enters the atmosphere with hypersonic speed.Therefore,it has far-reaching theoretical significance to study the electromagnetic scattering characteristics of plasma targets.On the other hand,the Linux platform is the mainstream operating system that dominates the high-performance computing market.The realization of the plasma target FDTD simulation on the Linux operating system is an inevitable trend in the development of electromagnetic numerical calculations.Therefore,this paper studies the FDTD algorithm for plasma targets based on Linux operating system.Calculate the RCS of the typical target and plasma coating target respectively,and realize the three-dimensional FDTD algorithm of transient field incidence.The work of this paper mainly includes the following points:1.We independent deduce the calculation process in the FDTD algorithm,and discuss the total field/scatter field technique,near-far field and far field transform techniques,as well as the convolutional form of absorbing boundary conditions and incident field sources suitable for plasma targets.2.We independent build a C++ compilation platform based on Linux system and manually configure three kinds of function libraries for record,configuration and calculation respectively to solve the problem of inconsistent types of calculation data and huge amount of computational data.And based on the above operating platform,debug the three-dimensional ADE-FDTD algorithm of transient field incidence.After that,optimizing the parameter reading interface of the algorithm program,calculate the RCS of the complex target.3.From the perspective of verifying the reliability of the FDTD algorithm platform,used the ADE-FDTD algorithm to calculate the RCS of the typical target,and the results are compared with the Mie theoretical results to illustrate the correctness of the FDTD algorithm design.Aiming at the three factors that affect the electromagnetic scattering results,we conclude that within a certain range,the finer the mesh and the more layers of absorbing boundary layers,the closer the FDTD calculation result is to the Mie theoretical analytical solution.At the same time,it is shown that the plasma layer coating target can weaken the electromagnetic scattering characteristics of the target to some extent.4.Focusing on the problem of plasma uniform coating targets,study on the effects of different dispersion parameters and electromagnetic scattering attenuation of the incident wave on the coating target,and concluded that: in the appropriate range,the thicker the plasma coating,the higher the natural frequency and the shorter the relaxation time,the more obvious the electromagnetic attenuation of the plasma coating on the target.Secondly,using ADE-FDTD to calculate the uniform coating target of multi-layer plasma,and through the contrast of the backward RCS of different coating layers,draw the conclusion: in the low frequency range of less than 3.5GHz,the more coating layers,the more obvious the target RCS reduction;however,in the high frequency range higher than 3.5 GHz,the number of coating layers has little effect on the value of RCS;after the number of coating layers reaches a certain value,such a rule is no longer applicable.At last,calculate the RCS of the front and back blunt cone models for uniformly coating the plasma layer.