Method of calculating far extrapolation of transient field of electromagnetic scattering through finite difference time domain

Abstract

A method of calculating far extrapolation of a transient field of electromagnetic scattering through finite difference time domain includes the steps of 1 dividing an area to be calculated into a main field area and a scattering field area according to the connecting boundary; 2 setting an extrapolation boundary in the scattering field area, and extrapolating electric fields and magnetic fields on the extrapolation boundary to obtain a far field; 3 setting transient incident waves, and sequentially updating the electric fields and the magnetic fields at each time step until the electromagnetic field distribution becomes steady; 4 writing the far field into a product of frequency factors and integral factors, and performing inverse Fourier transform on the integral factors to obtain a time domain expression; 5 setting an integral factor far field time domain response array; 6 performing Fourier transform on integral factor far field time domain response to obtain integral factor far field frequency domain response; 7 using far field and incident wave frequency domain response to obtain RCS (Radar Cross Section) changes with frequency. The method of calculating far extrapolation of the transient field of electromagnetic scattering through finite difference time domain writes the far field into the form of the product of the frequency factors and the integral factors due to the fact that the forms of frequency-time transform and time-frequency transform of the integral factors are simple, thereby simplifying the calculation and improving the efficiency.

Description

1. Technical field

[0001] The invention provides a transient field far-field extrapolation method for calculating electromagnetic scattering by a finite-difference time-domain method, which specifically relates to an electromagnetic simulation method of a finite-difference time-domain (FDTD) method, belonging to electromagnetic field simulation technology field. 2. Background technology

[0002] The finite difference time domain method (FDTD) is an important method of electromagnetic simulation and has been widely used in the electromagnetic field. The basic principle of this method is to discretize Maxwell's equations into a differential format, and use the interlaced characteristics of Yee's grid in space and time to realize the alternate update of electric field and magnetic field, and obtain the distribution of electromagnetic field with space and time. When using FDTD to calculate the electromagnetic scattering of the target, the calculation area is first divided into ...

Images