Progress of Airborne Laser Scanning Altimetry

The trends and prospect of airborne laser scanning altimetry in the near future are expected.The unsolved crucial problems in airborne laser scanning altimetry at present are pointed out.Geo-spatcial information technology is the focus research in the geo-science world presently.Information capturing,processing as well as application are the three main items.At the end of the 1980's of 20th,airborne laser scanning altimetry(ALSA) is an emerging and attractive technology in the field of remote sensing that is capable of rapidly capturing three dimensional geo-spactial information in multi-scales,and also give us a new technology for obtaining short time resolution and high spactial resolution data.Data capturing is continuous,not manually taken point to point,which also makes the automatic and intelligent data processing feasible.Laser pulse can partially penetrate the forest canopy,and the topography under the canopy can be derived directly.It is impossible for traditional survey methods,such as photogrammetry and plane surveying method.ALSA systems are opening new possibilities for a variety of survey applications and data end-users.ALSA is expected to bring a new revolutionary for surveying and mapping.Laser scanner systems available on the market are presently in a fairly mature state of art while the processing of ALSA data still is in an early phase of development.The algorithms and models for data processing are not robust and adaptive.The emergence of robust,reliable software tools that are available to the entire community will be one of the most significant areas of change in the next five years.Currently,the vast majority of the processing,manipulation and classification of ALSA data is conducted using proprietary software developed independently by research,the data providers or provided by the sensor manufacturer to its clients but not available as a separate package.