The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part Bl. Beijing 2008 
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Columns (Pixels) 
Crown volume 
5 CONCLUSION 
In anticipation of the potential of full-waveform lasers for 
vegetation mapping experimental systems have already been 
built and tested by NASA. Soon, also commercial 
full-waveform systems have became available. It appears that 
full-wave systems will much enhance our capability to map 
natural and artificial objects, but this comes at a cost: Instead of 
having one or a few trigger pulses the whole discrete signal 
Figl8 Map of treeheight 
4.3.2 Crown volume 
(ns) 
Fig 19 Sketch map of Crown volume 
.... T 
Registering the waveforms has made it possible to extract more 
than three echo pulse for each waveform and also to compute 
the width of the echoes. Pose-processing also enables detection 
of echoes with a smaller separation than the system does. A 
greater beam divergence would probably yield more multiple 
echo pulses since more objects would be illuminated by the 
same laser beam. 
4.3 Waveform for forestry application 
Lidar remote sensing has vast potential for the direct 
measurement and estimation of several key forest characteristics 
(Table 1). The direct measurements of small-footprint lidar are 
canopy height, subcanopy topography, and the vertical 
distribution of intercepted surfaces between the canopy top and 
the ground. Other forest structural characteristics, such as 
aboveground biomass, are modeled or inferred from these direct 
measurements 
4.3.1 Treeheight 
With small-footprint systems, the first return above a noise 
threshold can be used to estimate the top of the canopy, and the 
midpoint of the last return represents the ground return. 
Fig 17 Map of treeheight