Complex Envelope Approximate CN-PML Algorithm With Improved Absorption

By incorporating the complex envelope (CE) method and the higher order concept, unconditionally stable perfectly matched layer (PML) is proposed based on the Crank–Nicolson approximate-factorization-splitting (CNAFS) algorithm to simulate the bandpass problems in finite-difference time-domain lattice. The proposed algorithm has the advantages of the CNAFS algorithm, higher order PML concept, and CE method in terms of improving efficiency, enhancing absorbing performance, and simulating bandpass problems. A patched antenna model is carried to investigate effectiveness and efficiency.