Ergül, ÖzgürGürel, Levent2016-02-082016-02-082009-05-030010-4655http://hdl.handle.net/11693/22600We consider the accuracy of surface integral equations for the solution of scattering and radiation problems in electromagnetics. In numerical solutions, second-kind integral equations involving well-tested identity operators are preferable for efficiency, because they produce diagonally-dominant matrix equations that can be solved easily with iterative methods. However, the existence of the well-tested identity operators leads to inaccurate results, especially when the equations are discretized with low-order basis functions, such as the Rao-Wilton-Glisson functions. By performing a computational experiment based on the nonradiating property of the tangential incident fields on arbitrary surfaces, we show that the discretization error of the identity operator is a major error source that contaminates the accuracy of the second-kind integral equations significantly.EnglishAccuracy analysisFirst-kind integral equationsIdentity operatorLow-order basis functionsSecond-kind integral equationsSurface integral equationsArticle10.1016/j.cpc.2009.04.020