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@MastersThesis{Derenne:2002:CaSiIm,
               author = "Derenne, Maur{\'{\i}}cio",
                title = "Caracteriza{\c{c}}{\~a}o de um sistema imageador infravermelho 
                         termal atrav{\'e}s de suas resolu{\c{c}}{\~o}es espacial e 
                         radiom{\'e}trica",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2002",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2002-10-09",
             keywords = "imageadores infravermelho, fun{\c{c}}{\~a}o de 
                         transfer{\^e}ncia de modula{\c{c}}{\~a}o, raz{\~a}o sinal, 
                         ru{\'{\i}}do, fun{\c{c}}{\~a}o de espalhamento pontual, 
                         infrared scanners, modulation transfer function, signal to noise 
                         ratios, point spread functions.",
             abstract = "A faixa espectral do infravermelho termal para sensores 
                         aerotransportados ainda {\'e} pouco explorada no Pa{\'{\i}}s. O 
                         Instituto de Estudos Avan{\c{c}}ados (IEAv) do Centro 
                         T{\'e}cnico Aeroespacial (CTA) desenvolveu o Sistema Imageador 
                         Infravermelho Termal (SISIMI), um sensor-prot{\'o}tipo termal 
                         aerotransportado que opera na faixa de 8 a 12,5 Ám e com 
                         imageamento por varredura rotat{\'o}ria de 720 linhas/s. O 
                         objetivo desta disserta{\c{c}}{\~a}o {\'e} caracterizar o 
                         SISIMI atrav{\'e}s da determina{\c{c}}{\~a}o das suas 
                         resolu{\c{c}}{\~o}es espacial e radiom{\'e}trica. A 
                         resolu{\c{c}}{\~a}o espacial efetiva (EIFOV) foi calculada pelo 
                         levantamento da Fun{\c{c}}{\~a}o de Transfer{\^e}ncia de 
                         Modula{\c{c}}{\~a}o (MTF), enquanto a radiom{\'e}trica foi 
                         determinada pelo c{\'a}lculo da Diferen{\c{c}}a de Temperatura 
                         Equivalente ao Ru{\'{\i}}do (NETD). Foram realizados 
                         experimentos no Laborat{\'o}rio de Sensores {\'O}pticos do INPE 
                         e em campo, com voos para aquisi{\c{c}}{\~a}o de imagens. Para a 
                         determina{\c{c}}{\~a}o da MTF em laborat{\'o}rio, utilizou-se 
                         um colimador com fendas para simular a fun{\c{c}}{\~a}o impulso 
                         na entrada, e obter a Fun{\c{c}}{\~a}o de Espalhamento Pontual 
                         (FEP) na sa{\'{\i}}da. A Transformada de Fourier da FEP 
                         determinou a MTF do sensor. Na determina{\c{c}}{\~a}o da NETD, o 
                         SISIMI foi colocado em bancada para imagear tr{\^e}s recipientes 
                         cont{\'{\i}}guos contendo {\'a}gua limpa, simulando corpo 
                         negro. Aplicando-se uma diferen{\c{c}}a de temperatura entre alvo 
                         (recipiente central) e fundo (recipientes laterais), mediu-se a 
                         tens{\~a}o pico-a-pico do sinal e, vedando-se a entrada 
                         {\'o}ptica do sensor, mediu-se a tens{\~a}o {"}rms{"} do 
                         ru{\'{\i}}do. A curva de MTF de campo foi obtida por meio da 
                         simula{\c{c}}{\~a}o da fun{\c{c}}{\~a}o impulsiva em sobrevoo, 
                         com imageamento de tiras de alum{\'{\i}}nio polidas sobre lona 
                         pl{\'a}stica preta, e explorando-se suas propriedades de 
                         emissividade. Para levantamento da NETD, a lona foi o alvo e o 
                         concreto do p{\'a}tio de estacionamento de aeronaves serviu de 
                         fundo uniforme. A partir dos resultados encontrados em tr{\^e}s 
                         n{\'{\i}}veis (te{\'o}rico, laborat{\'o}rio e campo), foi 
                         feita a an{\'a}lise da consist{\^e}ncia dos valores levantados e 
                         determinadas as resolu{\c{c}}{\~o}es do prot{\'o}tipo do SISIMI 
                         dispon{\'{\i}}vel para testes: EIFOV = 12,6 ▒ 0,4 mrad, NETD = 
                         1,2 ▒ 0,2 K. Estes valores refletem as defici{\^e}ncias do 
                         imageador, mas s{\~a}o compat{\'{\i}}veis para um 
                         prot{\'o}tipo da d{\'e}cada de 80. S{\~a}o propostas 
                         modifica{\c{c}}{\~o}es no sensor a fim de melhorar o desempenho 
                         e a qualidade da imagem, como por exemplo alinhamento do sistema 
                         {\'o}ptico e refor{\c{c}}o na blindagem met{\'a}lica do motor 
                         do prisma e na fia{\c{c}}{\~a}o por onde passa o sinal 
                         el{\'e}trico. Recomenda-se o uso do SISIMI tanto em 
                         aplica{\c{c}}{\~o}es militares como em pesquisas ambientais. 
                         ABSTRACT: The thermal infrared spectral bands in airborne sensors 
                         are still little explored in Brazil. The Institute of Advanced 
                         Studies (IEAv) at the Aerospace Technical Center (CTA) developed 
                         the Thermal Infrared Imaging System (SISIMI), an aerial 
                         surveillance prototype sensor operating in the 8 to 12.5 um band 
                         with a rotating imaging scanner of 720 lines/s. The objective of 
                         this dissertation is to characterize the SISIMI trough its spatial 
                         and radiometric resolutions. The Effective Instantaneous Field of 
                         View (EIFOV) was calculated with the Modulation Transfer Function 
                         (MTF), while the radiometric resolution was determined with the 
                         estimate of the Noise Equivalent Temperature Difference (NETD). 
                         The experiments were conducted at INPE?s Optical Sensors 
                         Laboratory and in the field with image acquisition flights. For 
                         the MTF determination in the laboratory, a collimator with slits 
                         was used to simulate the inpulse function and to obtain the output 
                         Point Spread Function (PSF). The PSF Fourier Transform determined 
                         the sensor MTF. In the NETD estimate, the SISIMI was placed at a 
                         bench to image three ontiguous recipients with clean water, thus 
                         simulating a black body. The peak-to-peak signal tension was 
                         measured by the application of a temperature difference between 
                         the target (central recipient) and the background (side 
                         recipients) and the {"}rms{"} noise tension was measured after the 
                         sealing of the optical aperture of the sensor,. The field MTF 
                         curve was obtained through the impulse function simulation in an 
                         airplane pass, when polished aluminum stripes were placed over a 
                         thick black plastic sheet, and the emissivity properties were also 
                         investigated. To obtain the NETD in the field, the plastic canvas 
                         became the target and the airfield concrete parking lot was the 
                         constant background. Based on the results found at three levels 
                         (theoretical, laboratory and field) an analysis of the consistency 
                         of the values obtained was made and the resolutions of the SISIMI 
                         prototype were determined: EIFOV = 12.6 ▒ 0.4 mrad, NETD = 1.2 ▒ 
                         0.2 K. These values indicate limitations in the imager but are 
                         compatible with a prototype from the 80s?. Modifications are 
                         proposed in the sensor to improve the performance and quality of 
                         the images, such as an alignment of the optical system, 
                         reinforcement of the metallic shield of the prism?s motor and in 
                         the cabling that conducts the electric signals. The use of the 
                         SISIMI is suggested in military applications as well as in 
                         environmental research.",
            committee = "Lorenzzetti, Jo{\~a}o Antonio (presidente) and Setzer, Alberto 
                         Waingort (orientador) and Valeriano, Dalton de Morissson and 
                         Selingardi, Mario Luiz and Ghizoni, Cezar Celeste",
           copyholder = "SID/SCD",
         englishtitle = "Characterization of a thermal infrared line scanner trough its 
                         spatial and radiometric resolutions",
             language = "pt",
                pages = "129",
                  ibi = "6qtX3pFwXQZ3P8SECKy/ymS6A",
                  url = "http://urlib.net/rep/6qtX3pFwXQZ3P8SECKy/ymS6A",
           targetfile = "publicacao.pdf",
        urlaccessdate = "2020, Jan. 23"
}


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