摘要:

EMP simulation has been developing steadily for almost two decades. In the case of large EMP simulators intended for illumination of complete systems with correct spatial dependence, and their sometimes threat-like characteristics including correct frequency spectrum, the state of the art is rather mature. Various possibilities have been explored consistent with what Maxwell's equations allow one to do, leading to a somewhat logical list of simulator types. Some new thrusts in EMP simulation are pointed toward small EMP simulators which in some cases could be thought of as partial EMP simulators in that they illuminate a part of the system or synthesize part of the relevant sources for an EMP test. One of the promising concepts for special applications is the PARTES concept. Relying on integral equation descriptions of the electromagnetic interaction processes, and on the field equivalence principle for the synthesis of the electromagnetic fields, one can define a set of electric and magnetic dipoles which approximately synthesize proper EMP excitation by the use of superposition which implies an assumption of linearity. By varying the amplitude and phase of the sampling dipoles one can approximate any direction of incidence and polarization for a free-space plane wave over some limited volume of space.

ISSN:0272-6343    

DOI:10.1080/02726348308915173

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Abstract - An approach based on Prony's method is used to find the spatial poles of straight wires of varying length and radius from the far-field patterns. For the antenna case, poles having the largest residues are found near the feed region and antenna ends; smaller ones are found outside these regions. The poles are attributed to radiation from the exciting source and wire ends, due to charge acceleration, and from a slightly damped traveling wave. In the scattering case, the poles with the largest residues are located at the wire's ends for near—axial incidence and are again due to end radiation. By examining the residue magnitudes as a function of wire radius, a correlation is found with radiation from the feed region of an infinite antenna and from the ends of a semi-infinite antenna.

ISSN:0272-6343    

DOI:10.1080/02726348308915174

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The singularity expansion method is applied to determine the natural resonances of a perpendicular crossed wire structure oriented parallel to an imperfect ground plane. To account for the finite conductivity of the ground, three formulations are utilized. First, the rigorous Sommerfeld formulation is used; then for structures some distance from the ground an approximate Fresnel reflection coefficient approach is employed. For structures in proximity to the ground a lossy transmission line formulation is presented. Sample results from all three formulations are presented.

ISSN:0272-6343    

DOI:10.1080/02726348308915175

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The SEM parameters of a simple swept-wing aircraft model are determined. The technique consists of computing the transient surface current response at a number of locations on the model with various angles of incidence and then fitting each response waveform with a sum, of complex exponentials. The SEM description is derived from the resulting poles and residues.

ISSN:0272-6343    

DOI:10.1080/02726348308915176

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Through the use of an image ground plane, measurements of scattering patterns for objects with at least one plane of symmetry have been made. Until recently, only the magnitude of the patterns were available. Now the system's capability has been expanded to include accurate phase information. The system makes use of bistatic measurements and is interfaced with a MINC-11 minicomputer which provides fast and efficient automation of the measurement process as well as data analysis capability. The scattering range is operated using a microwave X-band system.

ISSN:0272-6343    

DOI:10.1080/02726348308915177

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0272-6343    

DOI:10.1080/02726348308928181

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0272-6343    

DOI:10.1080/02726348308928182

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor