Efficient implementation of FE-RTC-ABC preconditioner for FE-BI equations with DDM

Finite element-boundary integral (FE-BI) equations with domain decomposition method (DDM) provide a very powerful way of combining FE-BI method and DDM for modeling total electromagnetic scattering from cavities. But its resultant system of linear equations is usually ill-conditioned and has to be preconditioned for speeding up iterative solution process. This ill-conditioned matrix equation can be preconditioned using finite element-robin transmission condition-absorber boundary condition (FE-RTC-ABC) preconditioner. In this paper, we propose an efficient way to implement the FE-RTC-ABC preconditioner for large FE-BI-DDM system through applying the reverse Cuthill-McKee (RCM) algorithm in iterative solution process. Numerical results obtained show the effectiveness of the proposed implementation of the FE-RTC-ABC preconditioner for solving cavity problems.