Rigorous electromagnetic test of super-oscillatory lens

Abstract. A new theory of the propagation of low power electromagnetic test waves through the upper-hybrid resonance layer in the presence of magnetic field-aligned plasma density striations, which includes the effects of multiple scatter, is presented. The case of sinusoidal striations in a cold magnetoplasma is treated rigorously and then extended, in an approximate manner, to the broad-band striation spectrum and warm plasma cases. In contrast to previous, single scatter theories, it is found that the interaction layer is much broader than the wavelength of the test wave. This is due to the combined electric fields of the scattered waves becoming localised on the contour of a fixed plasma density, which corresponds to a constant value for the local upper-hybrid resonance frequency over the whole interaction region. The results are applied to the calculation of the refractive index of an ordinary mode test wave during modification experiments in the ionospheric F-region. Although strong anomalous absorption arises, no new cutoffs occur at the upper-hybrid resonance, so that in contrast to the predictions of previous single scatter theories, no additional reflections occur there. These results are consistent with observations made during ionospheric modification experiments at Tromsø, Norway.Key words. Ionosphere (active experiments; ionospheric irregularities) Radio science (ionospheric propagation)

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The Implementation of Information Receiving and Sharing of Satellite Cloud Image under the Complex Electromagnetic Environment

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.325-326.1530 ◽

2013 ◽

Vol 325-326 ◽

pp. 1530-1534

Author(s):

Zhong Jiang Yang ◽

Ming Ming Liu ◽

Tian Qi Yang

Keyword(s):

Electromagnetic Interference ◽

Local Area ◽

High Tech ◽

Ground Station ◽

Electromagnetic Test ◽

Satellite Cloud Image ◽

Satellite Ground Station ◽

Test Requirements ◽

Meteorological Satellite

Take the electromagnetic test of WT-8D satellite cloud image receiving system at a meteorological satellite ground station as an example, the test philosophy is analyzed, the test arrangement is made, and the maximum permissible value of level interference under the test requirements is calculated. By comparing the measuring data and the maximum permissible value of level interference, the relations between the antenna frequency and the value of level, the location of interference source, the intensity of interference source, and the generation laws of interference are all grasped. Aiming at the interference source, two methods are proposed respectively in this paper to inhibit the interference, one in the frequency domain and the other in the spatial domain. Then the method of information sharing of meteorological satellite cloud image is analyzed and discussed. As a conclusion, the receiving and transmittal quality of the meteorological satellite cloud image are improved, to prepare for the anti-electromagnetic interference in high tech local area in the future.

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