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Effect of incidence angle varying from 0 rad to Π/2 rad and intensity of radio waves on the performance of a silicon solar cell

Zerbo I., Zoungrana M., Saria M., Ouedraogo A., Bathiebo D. J.

Advances in Science and Technology. Research Journal

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2017

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Vol. 11, no 4

68--75

EN

In this work, a one dimensional approach is presented for modelling the effect of the incidence angle, varying from 0 rad to π/2 rad, and the intensity of radio waves on the performance of a polycrystalline silicon solar cell under constant multispectral illumination. By solving the continuity equation in steady state, we derived the expression of the density of excess minority carriers, the photocurrent density, the photovoltage, the electric power and their dependence on the incidence angle and the intensity of the electromagnetic field is analyzed. Using the electric power curves versus junction dynamic velocity we determined the electric power lost at the junction, the maximum electric power and we calculated the conversion efficiency for various incidence angle and intensity of the electromagnetic field. The leakage photocurrent density, deduced from the photocurrent density curves versus junction dynamic velocity, and the electric power lost at the junction allowed us to calculate the shunt resistance of the solar cell according to the incidence angle and the intensity of the electromagnetic field. The numerical data show the negative effect of radios waves on the performance of a silicon solar cell.

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Investigation on silicon solar cell capacitance and its dependence on both temperature and incidence angle

Sané M, Barro F I

Advances in Science and Technology. Research Journal

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2014

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Vol. 8, nr 24

9--12

EN

The aim of this work is to investigate a theoretical study of a vertical junction silicon solar cell capacitance under monochromatic illumination. By solving the continuity equation and using a one dimensional model in frequency modulation, we derive the analytical expressions of both excess minority carrier density and photovoltage. Based on these expressions, the solar cell capacitance was calculated; we then exhibited the effects of both temperature and incidence angle on the solar cell capacitance.

3

The interference characteristics of light-waves from a tilted and defocused cat-eye optical lens irradiated by laser beam

Zhao Y., Sun H., Zhang X., Wang Y.

Optica Applicata

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2011

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Vol. 41, nr 3

617--630

EN

When a tilted and defocused cat-eye optical lens is irradiated by laser beam, the reflected light-waves can be regarded as an off-axis spherical wave. Based on this idea and the theory of angular spectrum, our research has been directed towards some formulas describing the interference of the cat-eye reflected light with the reference incidence light. Through numerical computation, relationships governing the variation of the interference characteristics with parameters including the incidence angle, the tilted angle of the moving mirror, and the focal shift, are established. The relationships are experimentally validated. Our results have shown that the interference circles gradually move outwards, and the spot profile becomes broken with the increase of the incidence angle, the coordinates of the curvature center of the interference fringes are proportional to the incidence angle and the tilted angle of the moving mirror, the number of the interference fringes becomes larger along with the increase of the focal shift and the tilted angle of the moving mirror. The results can be used to estimate the tilted state of the cat-eye target.

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Interpretacja danych ENVISAT/ASAR o przemiennej polaryzacji na obszarach zurbanizowanych w kontekście charakterystyki stabilnych rozpraszaczy (Persistent Scatterers)

Perski Z., Ketelaar G., Mróz M.

Archiwum Fotogrametrii, Kartografii i Teledetekcji

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2006

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Vol. 16

467--482

EN

The scope of presented work was to apply the ENVISAT/ASAR data acquired in different alternating polarization modes and under different viewing geometry to characterize Persistent Scatterers (PS) in the context of their scattering mechanism. Persistent Scatterers are explored by SAR interferometry (InSAR) in the Persistent Scatterers Interferometry (PS-InSAR) method. This technique is nowadays one of the most actively developing branches of InSAR. It utilizes coherent natural "radar reflectors" with a consistent reflectivity pattern in time. The PS-InSAR method is the first one to allow the exploration of almost all archived SAR data over a certain area and can retrieve a long-term series of the observations of the individual PS points. Despite this, PS-InSAR used as an operational method of the scattering mechanisms of individual PS is still not fully explored. It is usually not known if the scatterer has specular, dihedral or trihedral geometry and if the reflection comes from one individual strong target or a set of targets located within the resolution cell. Knowledge about scatterer characteristics is very important to separate scatterers representing different deformation regimes: e.g. subsidence, deformations of the construction, soil compaction. This problem becomes crucial if spatial interpolation of the deformation signal is required. A high density of PS is typical for densely urbanized areas (> 100 PS/km²). Urban areas are also ones of the highest interests, in terms of inhabitants’ safety. For purposes of this study, Malbork City in Northern Poland was selected because of its very good coverage of ASAR alternating polarization data acquired under different modes and incidence angles. The specific various ASAR acquisitions have been designed for the purposes of the ESA AO-783 project which was focused on environmental and agricultural classification. A set of Persistent Scatterers has been collected by processing a stack of 55 ERS-1/2 SAR scenes (ESA C1P.3915 project) using Delft University of Technology’s implementation of the PSI method. The 5683 PS points have been obtained that have a coherent behavior. ASAR scenes were calibrated and an analysis of auto-interferogram phase and image amplitudes was performed. Further analysis of the ASAR data is focused on the relationship between incidence angle variations and amplitude, and on the change of polarization. The results were compared with the scattering models of canonical scatterers (specular, dihedral and trihedral). Preliminary results show that applications of variable incidence angle and alternating polarization data are a promising technique regarding scatterer characterization. However, to fully quantitatively analyze the data, precise coregistration is required.

PL

W artykule przedstawiono próbę wykorzystania danych ENVISAT/ASAR zarejestrowanych w różnych trybach polaryzacji przemiennej i przy różnej geometrii padania wiązki radarowej do scharakteryzowania rozpraszaczy stabilnych (Persistent Scatterers - PS) w kontekście określenia ich mechanizmu odbicia. Rozpraszacze stabilne wykorzystuje się w satelitarnej interferometrii radarowej (InSAR) w tzw. metodzie interferometrii rozpraszaczy stabilnych (Persistent Scatterers SAR Interferometry - PSInSAR). Zagadnienie to jest szczególnie istotne dla określenia charakteru mierzonej metodą PSInSAR deformacji w danym punkcie. Największe skupiska PS (pow. 100 PS/km²) spotyka się na obszarach zabudowanych, gdzie pozwala na to geometria obiektów składająca się z płaszczyzn, materiał, brak rozpraszania objętościowego powodowanego przez roślinność, a także stabilność w czasie. Dla przeprowadzenia omawianych badań wytypowano miasto Malbork z uwagi na niewielkie rozmiary (łatwa identyfikacja obiektów) i dobre pokrycie danymi ASAR w trybach polaryzacji przemiennej uzyskane w projekcie ESA AO-783. Zbiór rozpraszaczy stabilnych dla obszaru Malborka uzyskano metodą PSInSAR na podstawie serii 55 rejestracji ERS-1/2 SAR pozyskanych w ramach projektu ESA C1P.3915. Łącznie wyznaczono 5 683 punkty a następnie przeprowadzono analizę amplitudy i fazy dla wybranych obiektów na obrazach ASAR. Badano zależności fazy auto-interferogramów obrazów AP (alternate polarization) oraz zależności amplitudy od zmiany kąta padania wiązki. Otrzymane wyniki porównano z modelami odbicia fali radarowej od 3 elementarnych typów reflektorów: jednościennych, dwuściennych i trójściennych. Wstępne wnioski potwierdzają przydatność obrazów o polaryzacji przemiennej i różnym kącie padania wiązki do rozpoznawania charakterystyki PS.