Fast algorithm for electromagnetic scattering by buried 3-D dielectric objects of large size

Journal Article · Wed Sep 01 04:00:00 EDT 1999 · IEEE Transactions on Geoscience and Remote Sensing (Institute of Electrical and Electronics Engineers)

DOI:https://doi.org/10.1109/36.789654· OSTI ID:20005484

Cui, T J; Chew, W C

A fast algorithm for electromagnetic scattering by buried three dimensional (3-D) dielectric objects of large size is presented by using the conjugate gradient (CG) method and fast Fourier transform (FFT). In this algorithm, the Galerkin method is utilized to discretize the electric field integral equations, where rooftop functions are chosen as both basis and testing functions. Different from the 3-D objects in homogeneous space, the resulting matrix equation for the buried objects contains both cyclic convolution and correlation terms, either of which can be solved rapidly by the CG-FFT method. The near-scattered field on the observation plane in the upper space has been expressed by two-dimensional (2-D) discrete Fourier transforms (DFT's), which also can be rapidly computed. Because of the use of DFT's to handle the Toeplitz matrix, the Sommerfeld integrals' evaluation which is time consuming yet essential for the buried object problem, has been reduced to a minimum. The memory required in this algorithm is of order N (the number of unknowns), and the computational complexity is of order N{sub iter}N log N, in which N{sub iter} is the iteration number, and N{sub iter}{much{underscore}lt}N is usually true for a large problem

• Research Organization: Univ. of Illinois, Urbana, IL (US)
• Sponsoring Organization: US Department of Energy; US Department of the Air Force; Office of Naval Research; National Science Foundation
• DOE Contract Number: FG07-97ER14835
• OSTI ID: 20005484
• Journal Information: IEEE Transactions on Geoscience and Remote Sensing (Institute of Electrical and Electronics Engineers), Journal Name: IEEE Transactions on Geoscience and Remote Sensing (Institute of Electrical and Electronics Engineers) Journal Issue: 5 Pt 2 Vol. 37; ISSN 0196-2892; ISSN IGRSD2
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
ALGORITHMS
DIELECTRIC MATERIALS
ELECTROMAGNETIC RADIATION
FOURIER TRANSFORMATION
INTEGRALS
REMOTE SENSING