Efficient Analysis of Radio Wave Propagation for Complex Network Environments Using Improved DGTD Method

A radio wave propagation analysis scheme, which can model wireless channels in complex network environments with low resource consumption and high accuracy, is proposed based on the memory-efficient discontinuous Galerkin time-domain (DGTD) method in this article. The proposed scheme systematically explores the periodic/quasi-periodic structures present in the simulation domain through two innovative methodologies, subsequently leveraging the reusability of geometric periods to effectively mitigate memory consumption. First, considering the strong adaptability of the perfectly matched layer (PML) as truncated boundary conditions, the PML portion is designed to be a structure that can be partitioned into periodic/quasi-periodic blocks, in accordance with the overall physical structure of the domain. Second, the periodic/quasi-periodic structures overcome the limitation of the square lattice by establishing the multilevel Cartesian coordinate system, which accurately captures the periodic/quasi-periodic structure randomness in the network environment. Numerical examples demonstrate that this scheme effectively reduces resource consumption in deterministic channel analysis, while maintaining high accuracy and applicability. As the simulated region expands in scope and the internal structure becomes more intricate, the advantages of the proposed method become increasingly pronounced.