Vector boundary-element analysis for conical horn

A vector boundary-element method is developed for analyzing a conical horn in this paper. A moving boundary technique (MBT) is proposed for solving difficulties of the integration at high-order singularity points in a vector integral equation, and its validity is verified by calculating the reflection coefficients of an empty circular waveguide with a short-end. The circular symmetry of the conical horn is utilized to simplify the 3-D problem to 2-D one and the analyzing efficiency is significantly improved. A comparison of the reflection coefficients of the conical horn is given between the experimental data and the calculated results. Very good agreement has been seen, and the reliability and efficiency of the present method are thus verified.