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# Pulsed 1.5-$\mu$m LIDAR for Axial Aircraft Wake Vortex Detection Based on High-Brightness Large-Core Fiber Amplifier

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French Aerosp. Lab., French Aeronaut. & Space Res. Center (ONERA), Palaiseau
(Impact Factor: 2.83). 05/2009; 15(2):441 - 450. DOI: 10.1109/JSTQE.2008.2010463
Source: IEEE Xplore

ABSTRACT

In this paper, we present the development of an axial aircraft wake vortex light detection and ranging (LIDAR) sensor, working in Mie scattering regime, based on pulsed 1.5-mu m high-brightness large-core fiber amplifier. An end-to-end Doppler heterodyne LIDAR simulator is used for the LIDAR design. The simulation includes the observation geometry, the wake vortex velocity image, the scanning pattern, the LIDAR instrument, the wind turbulence outside the vortex, and the signal processing. An innovative high-brightness pulsed 1.5-mum laser source is described, based on a master oscillator power fiber amplifier (MOPFA) architecture with a large-core fiber. The obtained beam quality is excellent ( M 2 = 1.3), and achieved pulsed energy is 120 muJ with a pulse repetition frequency of 12 kHz and a pulse duration of 800 ns. A Doppler heterodyne LIDAR is developed based on this laser source with a high-isolation free-space circulator. The LIDAR includes a real-time display of the wind field. Wind dispersion is postprocessed. Field tests carried out at Orly airport in April 2008 are reported. Axial aircraft wake vortex signatures have been successfully observed and acquired at a range of 1.2 km with axial resolution of 75 m for the first time with fiber laser source.

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Article: Pulsed 1.5-$\mu$m LIDAR for Axial Aircraft Wake Vortex Detection Based on High-Brightness Large-Core Fiber Amplifier

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• "The wake vortex generated by a large aircraft is very hazardous to aviation safety because it might cause a following aircraft to roll out of control, particularly during the take-off and landing phases [26]. In order to avoid the wake vortex encountering hazard, many efforts have been made in the past decades to find proper approaches to monitor and detect wake vortices , and the existing approaches include Lidar [5] [6] [8] [13], Sodar [7] [30], and radar [1] [2] [12] [22] [24]. Among them, the radar detection is taken as a very potential approach for its long working range and good adaptability to different weather conditions. "
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