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a reciprocity formulation for the em scattering by an obstacle within a large open cavityA formulation based on a generalized reciprocity theorem is developed for analyzing the external high frequency EM scattering by a complex obstacle inside a relatively arbitrary open-ended waveguide cavity when it is illuminated by an external source. This formulation is also extended to include EM fields whose time dependence may be nonperiodic. A significant advantage of this formulation is that it allows one to break up the analysis into two independent parts; one deals with the waveguide cavity shape alone and the other with the obstacle alone. The external scattered field produced by the obstacle (in the presence of the waveguide cavity structure) is given in terms of a generalized reciprocity integral over a surface S(T) corresponding to the interior waveguide cavity cross section located conveniently but sufficiently close to the obstacle. Furthermore, the fields coupled into the cavity from the source in the exterior region generally need to propagate only one-way via the open front end (which is directly illuminated) to the interior surface S(T) in this approach, and not back, in order to find the external field scattered by the obstacle.
Document ID
19930068240
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Pathak, Prabhakar H.
(NASA Lewis Research Center Cleveland, OH, United States)
Burkholder, Robert J.
(Ohio State Univ. Columbus, United States)
Date Acquired
August 16, 2013
Publication Date
April 1, 1993
Publication Information
Publication: IEEE Transactions on Microwave Theory and Techniques
Volume: 41
Issue: 4
ISSN: 0018-9480
Subject Category
COMMUNICATIONS AND RADAR
Funding Number(s)
CONTRACT_GRANT: NAG3-476
CONTRACT_GRANT: N00014-89-J-1007
Distribution Limits
Public
Copyright
Other