Uniqueness of Plane Wave Integral Representation for Idealized Fields in Reverberation Chambers

We investigate the whole-body average specific absorption rate (WBA-SAR) of rats under various plane wave exposure characteristics, including different polarizations, incidence angles, distances between rats, and total number of rats. Unlike many other studies, we start our SAR analysis from one rat and expand it to 27 rats facing random directions in a three-dimensional area. In a one-rat analysis, we examine how the incidence direction and polarization affect the SAR of a single rat. Moreover, we look into how various incidence polarizations behave differently after they are transmited through a rat, the information of which is then used to analyze the effect of spacing among 27 randomly arranged rats. Next, we analyze the effect on spacing of the 27 rats deployed under a 52-plane-wave exposure, which is introduced to mimic a realistic reverberation chamber (RC) environment. We show the deviation in WBA-SAR according to the distance between rats, which provides guidelines for selecting the appropriate rat distance based on the number of animals and the exposure deviation within a limited working volume in an RC for large-scale experiments.

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PLANE WAVE SPECTRA IN GRATING THEORY: I. SCATTERING BY A FINITE NUMBER OF BODIES

Canadian Journal of Physics ◽

10.1139/p63-208 ◽

1963 ◽

Vol 41 (12) ◽

pp. 2106-2134 ◽

Cited By ~ 4

Author(s):

R. F. Millar

Keyword(s):

Plane Wave ◽

Convex Hull ◽

Integral Representation ◽

Scattered Field ◽

Indirect Method ◽

Scattering Amplitude ◽

Scattering Problem ◽

Wave Spectra ◽

Spatial Variables ◽

Uniqueness Of The Solution

A scalar plane wave is incident on a grating of N cylinders. A solution of the scattering problem, useful when N is large, is the ultimate goal. It is suggested that this may be accomplished by solving first the problem for a semi-infinite grating; this may be solved in terms of the scattering properties of an infinite grating, which, in turn, depend on the properties of an isolated cylinder.In the present paper, attention is confined to certain aspects of scattering by a few (in particular, one or two) cylinders. The field scattered by the cylinders is expressed as a sum of continuous plane wave spectra with amplitudes unknown, the scattering amplitude functions being considered as given for each cylinder in isolation. The field is studied, both outside the grating and between the elements. The convergence of the integral representation for the scattered field is treated in detail. Consequences of analyticity in the spatial variables of the scattered field are discussed; it is shown that the integral representation provides the continuation of the solution into a scatterer up to the convex hull of singularities of the field scattered by an isolated cylinder. Integral equations relating the scattering functions for cylinders in the grating and in isolation are derived. The uniqueness of the solution of these equations under a variety of boundary conditions is discussed by an indirect method; the case of two cylinders is treated in detail. It is inferred that there is at most one solution whose growth in the complex plane of the angle of observation is appropriate to scattering by a physical body.

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Theory and Errors in Stereo Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101426 ◽

1968 ◽

Vol 26 ◽

pp. 336-337

Author(s):

J. M. Pankratz

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Plane Wave ◽

Focal Length ◽

Foil Thickness ◽

Points Of Interest ◽

Transmission Electron ◽

Vertical Spacing ◽

Illuminating System

It is often desirable in transmission electron microscopy to know the vertical spacing of points of interest within a specimen. However, in order to measure a stereo effect, one must have two pictures of the same area taken from different angles, and one must have also a formula for converting measured differences between corresponding points (parallax) into a height differential.Assume (a) that the impinging beam of electrons can be considered as a plane wave and (b) that the magnification is the same at the top and bottom of the specimen. The first assumption is good when the illuminating system is overfocused. The second assumption (the so-called “perspective error”) is good when the focal length is large (3 x 107Å) in relation to foil thickness (∼103 Å).

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