Multisubgrid Cylindrical Parabolic Equation Model for Radio Environment Map Generation in a Large-Scale Region

Radio environment map (REM) is a crucial part of the cognitive radio system. In this letter, a multisubgrid (MSG) partition strategy based on geographic and geomorphologic characteristics for adaptive refinement is proposed. Combined with cylindrical parabolic equation model (CPEM), the proposed strategy can calculate local radiation distribution in a complex environment with high accuracy and efficiency. Local simulation results are mapped onto the global fine grid (FG) to generate REM in a large-scale region. REMs in the same maritime environment are simulated, respectively, by fine-grid-CPEM (FG-CPEM), coarse-grid-CPEM (CG-CPEM), and multisubgrid-CPEM (MSG-CPEM). Simulation results show that MSG-CPEM outperforms the CG-CPEM in terms of root mean square error and archives higher compute efficiency than that of FG-CPEM. It balances the accuracy and efficiency of the calculation for REM in a large-scale region with complicated geographic and geomorphologic characteristics.