LIDAR (Light Detection and Ranging)
LIDAR is an active remote sensing system that allows exceptionally accurate and rapid determination of terrain and structural features (e.g. height). LIDAR produces highly accurate three-dimensional data measurements that can then be utilized by mapping, guidance, and navigation systems. For example, LIDAR data utilized by Geographic Information Systems (GIS) software, and coordinated with differential Global Positioning System (GPS) data can produce extremely accurate terrain maps that be integrated with other tactical data (e.g. location of targets, etc). LIDAR technology measures distance by calculating the time delay between the emission and reception of a pulse of infrared light. The infra red light returns after reflecting off the surface of the target (e.g. in terrain feature mapping, the light reflects off the Earth's surface). LIDAR can operate in either profiling or scanning mode to illuminate the terrain under study.
LIDAR, in combination with GPS and Inertial Navigational System (INS) data, allows for highly accurate determination of altitude and position for aircraft, missiles, and other weapons and reconnaissance systems.
In addition to military and intelligence applications, LIDAR has been used to map ice flows and monitor storm erosion damage to beaches.
█ FURTHER READING:
Harney, R. C. "Physics and Technology of Coherent Infrared Radar." Proceedings of the SPIE Vol. 300 (1981).
Wertner, C., and Bilbro, J. "Coherent Laser Radar: Technology and Applications." Proceedings of the SPIE Vol. 1181 (1989).