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A NEW LOOK AT THE INTEGRAL EQUATION SOLUTION OF HIGH FREQUENCY DIFFRACTION PROBLEMS
A NEW LOOK PROBLEMS AT THE INTEGRAL EQUATION SOLUTION OF HIGH FREQUENCY DIFFRACTION Raj Mittra ABSTRACT In this paper we report a transform method for combining the integral equation and high frequency asymptotic techniques, e.g., the geometrical theory of diffraction or GTD. The method takes advantage of the fact that the Fourier transform of the unknown surface current distribution is p
INTEGRAL EQUATION FORMULATION FOR PREDICTION OF FAR-FIELD RADIATION PATTERNS FROM NEAR-FIELD MEASUREMENTS
INTEGRAL EQUATION FOBMU~ION RADIATION ~cay FOR PREDICTION 0"' FAR-PIELD PATTERNS FROM NEAR-FIELD MEASUREMENTS mRAND ABSTRACT An integral equation formulation in which the plane wave spectrum functions of a measured aperture appear as the unknowns is presented. Solutions to this equation are obtained by expanding the unknwons into sampling series and enforcing the equation at a finite number
TRANSIENT FIELDS OF RADIATING STRUCTURES
TRANSIENT Karl Jorg FIELDS OF RADIATING and Klaus STRUCTURES D. Rech* Langenberg ABSTRACT A rather simple and general analysis allows calculation of the exact transient near- and far-fields of thin loop antennas, thin linear antennas and apertures directly in the time domain without the knowledge of the time harmonic field. A numerical method (SEM) is used to derive the influence of the anten
MICROWAVE IMAGING OF ROTATING OBJECTS WITH NARROWBAND SIGNALS
MICROWAVE IMAGING OF ROTATING OBJECTS WITH NARROWBAND SIG NALS H. Gniss, K. Magura ABSTRACT The experimental investigations as described in this paper are based upon the evaluation of image-field distributions from the scattered fields of rotating objects measured at 36 GHz. Starting with a discussion of the reconstructing formalism and a suitable conversion into Fourier integral form, which is
NUMERICAL SOLUTION OF TRANSIENT ELECTROMAGNETIC SCATTERING PROBLEMS
NUMERICAL SOLUTION OF TRANSIENT ELECTROMAGNETIC SCATTERING PROBLEMS C. Leonard Bennett ABSTRACT A novel computational technique is presented for obtaining the numerical solution of transient electromagnetic scattering problems directly in the time domain. This technique consists of numerically stepping on in time the exact space-time integral equation that represents the solution of the scatt
APPLICATIONS OF GTD TO ANTENNA PROBLEMS
APPLICATIONS OF GTD TO ANTENNA PROBLEMS. Knud pontoppidan+ ABSTRACT: A general computer program package based on the geometrical theory of diffraction (GTD) is presented. The programs are based on a modular approach such that a complex geometry is broken down into smaller and simpler substructures. The applicability of the program package is illustrated by a number of examples ranging from di
DESIGN OF LOW LOSS 12 GHZ OUTPUT MULTIPLEXER FOR THE SECOND GENERATION TELESAT CANADA SATELLITE
DESIGN OF LOW LOSS 12 GHZ OUTPUT TELESAT MULTIPLEXER SATELLITE FOR THE SECOND GENERATION S. Ka11ianteris* CANADA ABSTRACT The basic design considerations for the 12 GHz low loss TE103 filters are described. The synthesis, optimization and realization of a new type low loss non-contiguous triplexer which uses the above filters and a WR75 manifold is presented. Test results of an engineering
DIELECTRIC WAFER FILTERS IN WAVEGUIDE
DIELECTRIC WAFER FILTERS IN WAVEGUIDE B.F. Nicholson and B.K. Watson* ABSTRACT and Filters comprising dielectric wafers in TE1O mode rectangular, or semi-circular waveguides are described. Their TEO1 mode circular suitability for use in overmoded guides and for high power levels is explained. Design procedures and a computer optimisation process are formulated which allow wafers of standard
RESONATED COMBLINE BANDPASS FILTER
RESONATED COMBLINE BANDPASS FILTER G.R. HOFFMAN ABSTRACT By loading the interior conductors of a classical combline filter with a series resonating impedance, very steep upper band skirt response may be generated. The procedure is particularly interesting for extending etched circuit combline filter technology to the lower microwave frequencies, with significant increases on filter performanc
COPLANAR LINES: APPLICATION TO BROADBAND MICROWAVE INTEGRATED CIRCUITS
COPLI-"'\NA.~ LINES: TO BROADBAND MICRaVAVE :rNI'ffiRATEDCIOCUITS APPLICATION M. HOODART' * ABSTRACI' The paper begins with a brief review of some of the shortcamings of the microwave microcircuit techniques most widely used in research and industry (e.g. microstrip, suspended stripline, and slot line). This is followed by a discussion of the advantages likely to be associated with the utiliz