An experimental study of RF optical transformation function [International Communications Satellite Systems Conference]

Author(s):  
Y. Oshima ◽  
T. Goda ◽  
H. Miyoshi ◽  
M. Hamamoto ◽  
M. Tanaka
2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Ki-Woong Bae ◽  
Dong-Wook Seo ◽  
Noh-Hoon Myung

The material parameters of a metamaterial (MTM) are determined by the transformation function used in the optical transformation. Some previously reported MTMs, such as the invisibility cloak, the field rotator, and the field concentrator, were designed by a linear transformation. Their impedance was matched to the background so that no reflection was found; however, the material parameters were mismatched to the background due to the linear transformation function. In the present work, the parameters were matched by using high-order polynomial functions as the transformation function. Since similar materials are filled in boundary cells of the finite-difference time-domain (FDTD) algorithm, the stair-casing error was reduced and the tolerance against boundary abrasion was increased. The frequency response of the proposed method was analyzed. The proposed method is applicable to MTM structures that have complex boundary shapes. In this work, circular and elliptic boundary shapes were considered as examples.


Author(s):  
Norio Baba ◽  
Norihiko Ichise ◽  
Syunya Watanabe

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.


1962 ◽  
Vol 5 (4) ◽  
pp. 387-394 ◽  
Author(s):  
Bruce Quarrington ◽  
Jerome Conway ◽  
Nathan Siegel
Keyword(s):  

1974 ◽  
Vol 126 (2) ◽  
pp. 243-248
Author(s):  
A WAKABAYASHI ◽  
T KUBO ◽  
K CHARNEY ◽  
Y NAKAMURA ◽  
J CONNOLLY

1963 ◽  
Vol 45 (3) ◽  
pp. 374-383 ◽  
Author(s):  
Donald C. McIlrath ◽  
George A. Hallenbeck ◽  
Hubert A. Allen ◽  
Charles V. Mann ◽  
Edward J. Baldes ◽  
...  
Keyword(s):  

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