Radiation effects on electronic circuits in a spatial environment

The failings bound to the deterioration of the components under irradiations are complex and numerous. This paper describes the different kinds of radiations present in the space as well as their interactions with the materials composing the integrated circuits used in the spacecraft. Our survey will be focused on the Single Event Upset phenomenon induced by the passage of only one ionizing particle with applications on the Samsung SDRAM

Analysis of fractal radiation patterns from concentric-ring hexagonal arrays

These hexagonal arrays are becoming increasingly popular, especially for their applications in the area of wireless communications. The overall objective of this article has been to use the theoretical foundation developed for the analysis of radiation patterns and design of the hexagonal arrays. A technique has been developed for the analysis of radiation patterns from concentric ring arrays. A family of functions, known as generalized Weierstrass functions, has been shown to play a key role in the theory of fractal radiation pattern analysis

Analysis of radiation patterns and feed illumination of the reflector antenna using the physical and geometrical optics

Reflector antennas are characterized by very high gains (30 dB and higher) and narrow main beams. They are widely used in satellite and line-of-sight microwave communications as well as in radar. Reflector antennas operate on principles known long ago from the theory of geometrical optics. The first reflector system was made by Hertz back in 1888 (a cylindrical reflector fed by a dipole). The radiation fields from aperture antennas, such as slots, open-ended waveguides, horns, reflector and lens antennas, are determined from the knowledge of the fields over the aperture of the antenna. In this paper, we analyzed the effects of feeds relating to the parabolic reflectors such as waveguide and horn. We show the variations of the gain in the electric and magnetic planes (E and H) according to the angle of incidence. In our case, we use the origin to be at the focus

Influence of Gravity on noncommutative Dirac equation

In this paper, we investigate the influence of gravity and noncommutativity on Dirac equation. By adopting the tetrad formalism, we show that the modified Dirac equation keeps the same form. The only modification is in the expression of the covariant derivative. The new form of this derivative is the product of its counterpart given in curved space-time with an operator which depends on the noncommutative $\theta$-parameter. As an application, we have computed the density number of the created particles in presence of constant strong electric field in an anisotropic Bianchi universe.Comment: 9 pages, correct some miprints, Accepted for publication in journal of Mod. Phys. Letters