Abstract: This paper deals with the problem of truncating the open boundaries of cylindrical waveguides under the rectangular coordinate system, and gives the CPML’s construction parameters. The performance of CPML was simulated when it was used to truncate the cylindrical waveguides excited by the sources with different frequencies and modes. The numerical results show that the maximum relative error is less than -70 dB, which can meet the requirement of numerical simulation.

Key words: convolutional perfectly marched layer, cylindrical waveguide, open boundary, relative error