Fast iteration algorithm for integral equations of the first kind arising in 2D diffraction by soft obstacles

We propose a new iteration numerical algorithm to solve boundary integral equations of the first kind arising in the 2D scattering by soft obstacles. The main idea is to operate on each iteration step with an integral equation, which has a convolution kernel, by changing the full kernel with a special averaging procedure. The practical convergence of the algorithm is demonstrated by some examples for three different geometries. If M is the number of iterations then the computational cost of the algorithm is MNlog(N).