Julien Totems

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In a Phase-Induced Amplitude Apodization (PIAA) coronagraph, the telescope pupil is geometrically remapped in a gaussian-like beam by a set of two highly aspheric optics (mirrors or lenses). Thanks to this largely lossless apodization, the PIAA coronagraph offers a nearly full throughput (94.3% for the configuration tested, excluding losses due to optics(More)
From an unprecedented experiment using airborne measurements performed over the rich forests of Réunion Island, this paper aims to present a methodology for the classification of diverse tropical forest biomes as retrieved from vertical profiles measured using a full-waveform LiDAR. This objective is met through the retrieval of both the canopy height and(More)
In June 2013, a ground-based mobile lidar performed the ~10,000 km ride from Paris to Ulan-Ude, near Lake Baikal, profiling aerosol optical properties in the cities visited along the journey and allowing the first comparison of urban aerosols optical properties across Eurasia. The lidar instrument was equipped with N2-Raman and depolarization channels,(More)
Although pulsed coherent laser radar vibrometry has been introduced as an improvement over its continuous wave (CW) counterpart, it remains very sensitive to decorrelation noises, such as speckle, and other disturbances of its measurement. Taking advantage of more polyvalent polypulse waveforms, we address the issue with advanced signal processing. We have(More)
Vibration sensing by laser radar with a pulsed emission is a promising technique for long range target recognition and identification. However, compared to its continuous-wave counterpart, it is impaired by its greater sensitivity to speckle noise and its lack of robustness to multiple independent vibrations of the target surface. Using poly-pulse waveforms(More)
We present our work to jointly optimize modulation waveforms and signal processing for long range vibration sensing using a heterodyne coherent laser radar in pulsed mode. The performance of various existing Instantaneous Frequency (IF) estimators is compared through simulation, taking into account Continuous Wave (CW) and pulse-pair waveforms, and for the(More)
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