CUDA-based Space-variant Electromagnetic Field FDTD Accelerate Calculation And Visualization

The FDTD method is a commonly used numerical method for electromagnetic calculation.It divides the target object into a large number of meshes and then calculates the electromagnetic field alternately and iteratively in the space by using the leapfrog algorithm.The characteristics of the FDTD method makes it intuitive,understandable,highly parallelizable,and widely applicable.Therefore,it is applied in various engineering fields of computational electromagnetics.With the rapid development of hardware,especially GPU,CPU,etc,the FDTD method has an increasingly broad application prospect.In practical problems,the electromagnetic propagation environment is usually very complicated,and the parameters of the electromagnetic calculation change with the spatial position,which will directly affect the accuracy of the electromagnetic simulation results.In view of the research of electromagnetic wave propagation and visualization in a space-variant environment such as the maritime environment,this paper has carried out the following work:1.In order to solve the problem of electromagnetic propagation in a space-variant environment,taking the maritime as an example,combined with Maxwell's curl equation and a kind of space-variant refractive index model proposed by ITU,the FDTD electromagnetic calculation model of space-variant environment is derived.2.After analyzing the structure and data characteristics of the FDTD propagation model in space-variant environment.Based on the CUDA,the correspondence between the FDTD computational grid and the CUDA thread structure is established by using the index table.The electromagnetic parallel computing structure is optimized for the computational memory,and the parallel computing of the electromagnetic data acceleration in the space-variant environment is realized.3.By analyzing the data structure characteristics of the required rendered graphics,combined with the OpenGL,a parallel computing method and visualization flow with dual VBO is proposed.Writing a program to realize CUDA-based electromagnetic field FDTD acceleration calculation and visualization in space-variant environment.According to the above calculation structure and visualization method,the numerical calculation and visualization of FDTD are completed.The simulation results show that while the computational grid reaches 256×256×256,the proposed method has a calculation error that less than3.6×10^-5,which guarantees the calculation accuracy of electromagnetic propagation in space-variant environment.The calculation speed reaches 403.51 Mcells/s,and the acceleration ratio reaches 35.36,the calculation speed is greatly improved.The visual graphics frames is stable at more than 24 frames,it shows that the system has a very stable display.Therefor,the proposed method can provide important support for electromagnetic propagation analysis in space-variant environment.