Abstract

In this article, we study the existence and uniqueness of outgoing solutions for the Helmholtz equation in locally perturbed half-planes with passive boundary. We establish an explicit outgoing radiation condition which is somewhat different from the usual Sommerfeld's one due to the appearance of surface waves. We work with the help of Fourier analysis and a half-plane Green's function framework. This is an extended and detailed version of the previous article Durán et al. (2005, The Helmholtz equation with impedance in a half-plane. C. R. Acad. Sci. Paris, Ser. I, 340, 483-488). © 2006 Oxford University Press.