The Laser Vegetation Imaging Sensor: a medium-altitude, digitisation-only,airborne laser altimeter for mapping vegetation and topography

The Laser Vegetation imaging Sensor (LVIS) is an airborne, scanning laser a ltimeter, designed and developed at NASA's Goddard Space Flight Center (GSF C). LVIS operates at altitudes up to 10 km above ground, and is capable of producing a data swath up to 1000 m wide nominally with 25-m wide footprint s. The entire time history of the outgoing and return pulses is digitised, allowing unambiguous determination of range and return pulse structure. Com bined with aircraft position and attitude knowledge, this instrument produc es topographic maps with dm accuracy and vertical height and structure meas urements of vegetation. The laser transmitter is a diode-pumped Nd:YAG osci llator producing 1064 nm, 10 ns, 5 mi pulses at repetition rates up to 500 Hz. LVIS has recently demonstrated its ability to determine topography (inc luding sub-canopy) and vegetation height and structure on flight missions t o various forested regions in the US and Central America. The LVIS system i s the airborne simulator for the Vegetation Canopy Lidar (VCL) mission (a N ASA Earth remote sensing satellite due far launch in year 2000), providing simulated data sets and a platform for instrument proof-of-concept studies. The topography maps and return waveforms produced by LVIS provide Earth sc ientists with a unique data set allowing studies of topography, hydrology, and vegetation with unmatched accuracy and coverage. (C) 1999 Elsevier Scie nce B.V. All rights reserved.