A frequency-independent method of truncated wedge incremental length diffraction coefficients for large complex polygonal surfaces

We propose a frequency-independent method based on the truncated wedge incremental length diffraction coefficients (TW-ILDC). Considering the decay of fringe-wave surface currents and the fact that the discontinuous edges of a triangular patch in large complex objects are often small, the truncated lengths of such edges are often slightly varied. Hence a fixed length can be taken from the engineering approximation to simplify the tracing procedure of TW-ILDC. Compared to the traditional ILDC method, the proposed approach has higher accuracy and gets rid of the non-removable singularities. The validation of the new method has been confirmed by numerical examples.