Free Space Optics
Mostrando 1-6 de 6 artigos, teses e dissertações.
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1. Localized beams in optical tweezers with conventional and metamaterial particles / Feixes localizados em pinças opticas com particulas convencionasi e metamateriais
In this thesis, we explore some applications of localized beams in FSO - Free Space Optics - and optical tweezers, greater emphasis been given to the second one. For FSO, we show that it is possible to choose the desired longitudinal intensity pattern by using optical elements adequately modeled in their phase functions: the axicons. In this way, these beams
Publicado em: 2009
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2. Design of an optical transceiver for free space optical digital communication. / Projeto de um transceptor óptico para comunicação digital em espaço livre.
Os sistemas de comunicação óptica por espaço livre, comumente denominados sistemas FSO (Free Space Optics), servem para estabelecer enlaces de comunicação do tipo wireless, ponto-a-ponto, a uma elevada taxa de dados e com alcances que podem variar de algumas centenas de metros a alguns quilômetros. O interesse pela tecnologia FSO tem sido estimulado p
Publicado em: 2007
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3. SINGLE PHOTON COUNTING IN THE NEAR- AND MID-INFRARED VIA FREQUENCY UP-CONVERSION APPLIED TO QUANTUM COMMUNICATIONS / CONTAGEM DE FÓTONS NO INFRAVERMELHO PRÓXIMO E MÉDIO VIA CONVERSÃO DE FREQÜÊNCIAS APLICADA A COMUNICAÇÕES QUÂNTICAS
Two single photon counting devices, operating at near- and mid-infrared wavelengths, are introduced and experimentally investigated. Both use a twostage technique, comprised of an initial frequency up-conversion procedure inside a nonlinear crystal followed by a silicon avalanche photodiode. Whereas the first project consists on detection of single photons a
Publicado em: 2007
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4. Estudo e modelagem de canal optico atmosferico utilizando o Lightsim como plataforma de simulação / Study and modeling of atmospheric optical channel using lightsim as simulation platform
This is a study and simulation on free space optical communication analyzing many factors that can influence the transmitted signal quality. The use of an atmospheric channel to propagate optical signal is called FSO, Free Space Optics, and it is a cheap alternative for low length paths, because the low cost in it development, installation and maintenance. T
Publicado em: 2007
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5. Retroperitoneoscopy for treatment of renal and ureteral stones
OBJECTIVE: To assess the efficacy of retroperitoneoscopy for treating stones in the renal pelvis and proximal ureter. MATERIALS AND METHODS: In the period from August 2003 to August 2004, 35 retroperitoneoscopies for treatment of urinary stones were performed on 34 patients. Fifteen patients (42%) had stones in the renal pelvis, and in 2 cases, there were as
International braz j urol. Publicado em: 2005-04
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6. SIMULATION AND DEVELOPMENT OF A FREE-SPACE OPTICS IN RIO DE JANEIRO AND RELATIONSHIP WITH ITU-T G.826 / SIMULAÇÃO E DESENVOLVIMENTO DE UM ENLACE DE FREE-SPACE OPTICS NO RIO DE JANEIRO E A RELAÇÃO COM A ITU-T G.826
Very few works had been developed in Brazil, dealing with Free-Space Optics (FSO). In this arrangement, a laser beam carries information for a short range (up to 3-4 km), avoiding the use of optical fiber. FSO is a rapidly-improved solution and very economical, specifically in urban areas. In this work a FSO system operating in Rio is described. This work pr
Publicado em: 2005