“…Nowadays, laser altimeters placed on different platforms (airborne, satellite) have been widely used in lots of areas like mass balance estimation in Antarctica, vegetation vertical structure, long trend monitor of sea level and so on (Anderson et al, 2005;Alexander et al, 2010;Garvin et al, 1998;Gong et al, 2011;Hyyppä et al, 2001;Joerg, et al, 2015;Means and Acker, 1999;Naesset and Bjerknes, 2001;Nilsson, 1996;Smith et al, 1998;Tian et al,2015). For the reason that the measurement of altimeter can not only provide high precision elevation or distance information, it can also record the complete waveform of the backscattered signal echo, especially for the full-waveform laser altimeter (Mallet, 2009).…”