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Directed Infrared Countermeasures (DIRCM) are used to protect aircrafts against missiles with infrared (IR) guidance. They are employed by military and civilian aircrafts, drawing away the guidance system of a missile as it attempts to lock onto the IR signature of the turbines. Unfortunately, the protection provided by these devices generates risks and challenges that must be overcome. In this paper, investigations on DIRCM risks to fighter aircraft pilots are carried out. Different kinds of lasers employed in actual DIRCMs are analyzed and the results show that, depending on their frequency (wavelength), damages can occur up to a distance of 4.8 km. The transmittance through the canopy of an F-5 fighter aircraft is evaluated and its effects on the IR propagation are predicted by the use of software called Counter-Measurements in PYTHON (CMePy). Results show that, even when there are interfaces between the pilot and the source of radiation, damages can occur, showing the importance of this investigation to the right understanding of this subject and future mitigations.

This paper presents the design and characterization of a near infrared (NIR) tunable quantum well infrared photodetector (QWIP). The detection was achieved using interband electron transitions between quantized energy levels for holes (light and heavy) in the valence band and quantized energy levels for electrons in the conduction band. The quantum wells are made asymmetric (step wells) to allow transitions between energy levels with different parity quantum numbers. The structure is modeled by solving self-consistently the Schrodinger and Poisson equations with the help of the shooting method. The photocurrent of the fabricated GaAslInGaAs photodetector is measured at the temperature of 10 K and the observed response lies between 825 and 940 nm. When the bias is 0.5 V, a narrow response centered in 840 nm is achieved. Applying 4.5 V the peak response moves to 930 nm, The results demonstrate the possibility of tunable detection in the NIR band with great versatility.

O crescente emprego de mísseis infravermelhos de ombro contra alvos aéreos demanda o constante desenvolvimento de métodos de emprego de sistemas de contramedidas. Buscando analisar a efetividade das contramedidas do tipo flares, cenários operacionais são modelados, utilizando o software SIMIS nas bandas MWIR (Medium Wavelenght Infrared) e SWIR (Short Wavelenght Infrared). As imagens fornecidas foram empregadas em um modelo implementado em Simulink para se analisar os efeitos do lançamento do flare em autodiretores de 1ª e 2ª geração. A influência do emprego das contramedidas com dois métodos diferentes de lançamentos foi analisada. Os resultados obtidos ressaltam a importância e a necessidade do desenvolvimento de ferramentas computacionais mais complexas, visando ao desenvolvimento da doutrina de emprego de flares.