Waveform analysis of lidar data for targets in cluttered environments

Abstract

In this paper we study the potential of using deconvolution techniques on full-waveform laser radar data for pulse detection in cluttered environments, e.g. when a land-mine is partly occluded by vegetation. A pulse width greater than the distance between the reflecting surfaces within the footprint results in a signal that is composed by overlapping reflections that may be very difficult to analyze successfully with standard pulse detection techniques. We demonstrate that deconvolution improves the chance of successful decomposition of waveform signals into the components corresponding to the reflecting objects in the path of the laser beam. Experimental data were analyzed in terms of pulse extraction capability and distance accuracy. It was found that deconvolution increases the pulse extraction performance, but that surfaces closer than about 40% of the laser pulse width are still very difficult to detect and that the number of spurious, erroneously extracted, points is the price to pay for increased pulse detection probability.

High range resolution laser scanner with full waveform recording

“…2,3,4 A comparison of different processing techniques -such as simple peak finding, leading edge detection, peak-gauss fitting, correlation and deconvolution techniques -with respect to accuracy and resolution indicates that the deconvolution technique is very attractive as it resolves the waveform by reducing the influence of laser pulse and detector response. 1,5 With deconvolution, the range resolution can be improved to less than the pulse length 6 ; the ability to resolve surfaces separated by a distance five times smaller than the pulse length has been demonstrated in the literature 7 . Basic short pulse response for mines in background has been investigated in a model using simulated high resolution laser radar waveforms assuming short pulse lasers and high bandwidth detection.…”

Fusion of waveform LiDAR data and hyperspectral imagery for land cover classification

“…Compared to discrete return LiDAR, FWL provides denser sampling of target structure along the pulse traveling path, as well as the capacity to estimate object geometric properties through waveform shape. Airborne LiDAR with waveform digitizing can be particularly useful for discovering obscured targets, especially in cluttered or complex environments due to its unique ability to resolve echoes from multiple closely spaced reflectors (Tolt and Larsson, 2007).…”