Nlos
Mostrando 1-7 de 7 artigos, teses e dissertações.
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1. SIGNAL VARIABILITY, COHERENCE BANDWIDTH AND DELAY SPREAD ON MOBILE RADIO PROPAGATION ENVIRONMENT AT 3.5GHZ / VARIABILIDADE DO SINAL, BANDA DE COERÊNCIA E ESPALHAMENTO TEMPORAL EM AMBIENTE DE RÁDIO PROPAGAÇÃO MÓVEL EM 3,5GHZ
This work presents a study of signal variability, coherence bandwidth and delay spread of a WiMAX signal transmitted through a mobile radio propagation environment. The statistical analysis of the received signal is compared with theoretical distributions. The transmitted WiMAX signal has its physical layer based on OFDM-256 and 3.4 GHz as central frequency.
Publicado em: 2009
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2. Localização de usuários usando o sistema celular. / Users localization using cellular system.
The mobile location technique using the cellular system received a special attention from the telecommunication manufacturers and operators, regarding the need of accomplishing the established demands by the emergency service calls and other commercial ones. This study analyzes the main location methods proposed in the literature, including, in each one, the
Publicado em: 2007
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3. Efeitos da emissÃo dos efluentes domÃsticos na proliferaÃÃo de Aeromonas spp. em Ãguas de superfÃcie e pescado do estuÃrio do Rio Bacanga, SÃo Luis â MaranhÃo / The issuance of domestic sewage in the proliferation of Aeromonas spp. in surface water and fish of the estuary of the River Bacanga, SÃo Luis - MaranhÃo
For the detection of Aeromonas were collected 90 samples of surface water and 30 fish in the estuary of the river in St. Louis Bacanga / MA in the period March to October 2004. The samples were submitted, while the method of direct plating on Gelatin Phosphate Salt Agar (Agar GSP plus 20flglrnL of ampicillin) to count (CFU / g or RNL) and the determination o
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/03/2005
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4. RAY TRACING ANALYSIS OF THE EFFECTS OF PROPAGATION ON MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) CHANNELS / ANÁLISE DOS EFEITOS DA PROPAGAÇÃO EM CANAIS COM MÚLTIPLAS ENTRADAS E MÚLTIPLAS SAÍDAS (MIMO) COM BASE NO TRAÇADO DE RAIOS
A ray tracing model based on the method of images has been applied to study the propagation of radio waves in the regions of Copacabana and Ipanema in Rio de Janeiro. In such highly urbanized environments, it can be realistically assumed that propagation is restricted to a horizontal section of the street canyons characterized by the blocks of buildings. Sev
Publicado em: 2005
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5. Modelo 2,5D de predição de propagação para ambientes interiores utilizando o método do traçado de raios
A 2.5D ray-tracing propagation model is proposed to predict radio loss in indoor environment. Specifically, we opted for the Shooting and Bouncing Rays (SBR) method, together with the Geometrieal Theory of Diffrartion (GTD). Besides the line-of-sight propagation (LOS), we consider that the radio waves may experience reflection, refraction, and diffraction (N
Publicado em: 2005
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6. RADIOLOCALIZAÇÃO DE TERMINAIS DE COMUNICAÇÕES MÓVEIS / RADIOLOCATION OF MOBILE COMMUNICATIONS TERMINALS
This work addresses the radiolocation problem of a moving terminal in a cellular mobile communications environment. New alternatives are developed for position estimation, assuming that the Time of Arrival (ToA) measurements obtained from radio link are corrupted by additive noise and have positive mean error during random periods of time due to the non-line
Publicado em: 2004
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7. ESTUDO E SIMULAÇÃO DE TÉCNICAS DE LOCALIZAÇÃO DE TERMINAIS EM AMBIENTES MICROCELULARES / INVESTIGATION AND SIMULATION OF TERMINAL LOCATION TECHNIQUESIN MICROCELLULAR SYSTEMS
The location of mobile terminals in mobile cellular systems has been receiving increasing attention in the last few years. This interest in focused not only in security aspects but also in the development of new services for commercial application. In this Dissertation a simulation environment for mobile stations location in microcellular systems was develop
Publicado em: 2003