A fast method for the creeping ray contribution to scattering problems
2006 (English)In: Mathematical Modeling of Wave Phenomena / [ed] Nilsson, B; Fishman, L, MELVILLE, NY: AMER INST PHYSICS , 2006, Vol. 834, 56-64 p.Conference paper (Refereed)
Creeping rays can give an important contribution to the solution of medium to high frequency scattering problems. They are generated at the shadow lines of the illuminated scatterer by grazing incident rays and propagate along geodesics on the scatterer surface, continuously shedding diffracted rays in their tangential direction. In this paper we show how the ray propagation problem can be formulated as a partial differential equation (PDE) in a three-dimensional phase space. To solve the PDE we use a fast marching method. The PDE solution contains information about all possible creeping rays. This information includes the phase and amplitude of the field, which are extracted by a fast postprocessing. Computationally the cost of solving the PDE is less than tracing all rays individually by solving a system of ordinary differential equations(ODE). We consider an application to monostatic radar cross section problems where creeping rays from all illumination angles must be computed.
Place, publisher, year, edition, pages
MELVILLE, NY: AMER INST PHYSICS , 2006. Vol. 834, 56-64 p.
, AIP CONFERENCE PROCEEDINGS, ISSN 0094-243X ; 834
scattering problems, geometrical optics, creeping rays, numericl methods
IdentifiersURN: urn:nbn:se:kth:diva-42087ISI: 000237610000004ScopusID: 2-s2.0-33845582579ISBN: 0-7354-0325-2OAI: oai:DiVA.org:kth-42087DiVA: diva2:446429
nd Conference on Mathematical Modeling of Wave Phenomena. Vaxjo, SWEDEN. AUG 14-19, 2005
QC 201110072011-10-072011-10-052011-10-07Bibliographically approved