We have developed a multi-spectral SWIR lidar system capable of measuring simultaneous spatial-spectral information for imaging and spectral discrimination through partial obscurations. Our system utilizes a supercontinuum laser source and eight narrowband spectral channels in the 1000 nm to 1600 nm region. The system employs a steering mirror, which enables us to scan the region of interest and collect spectral and spatial data as a point-by-point scan. The system is designed to detect weak signal returns in the few-photon regime. The technique promises more capable classification and target detection of spectrally diverse targets in obscured environments with potential applications for mapping of ground type through forest canopy, pollution monitoring of water ways, and intelligence, surveillance, reconnaissance and target detection (ISRT). Custom targets designed to provide distinct spectral response are employed to ascertain the system’s response. The lidar system is calibrated by measuring the return signal from a highly reflective flat Spectralon target; this enables us to determine the reflectivity of the objects of interest. Spectral response of the targets are analyzed and their estimated reflectivity is reported. The same targets are studied in the presence of two partial obscurants. The objects are easily identified even though the return signal is attenuated by a factor of seven. The general spectral shape of the targets are preserved in the presence of the obscurants. More challenging objects and environments and various methods to recover the spectral response of the objects are currently being pursued.
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