This paper presents the performance and accuracy standards for the use of LIght Detection And Ranging (LIDAR) technology (also referred to as "laser swath mapping" and "airborne laser profiling") to construct Digital Elevation Models (DEMs).
Modern urban data management is based on maintenance and exploitation of the existing urban and environmental situation. Development of a growing city can be effectively monitored when existing structures are known with sufficient accuracy. Another requirement for efficient town and environmental planning is that the database is made available in computer compatible form i.e. digital form.
Traditionally, database generation has been done from large scale Cadastral maps and aerial photographs. However, these source data must be checked carefully for positioning errors. Frequently errors between different data sets interrupt the intended application. A cheap data source are commercially available ortho-photos, but the quality of these has to be checked in terms of positioning errors and age and their general suitability for the application. Positioning errors, which are inherent in ortho-photos, are unknown in DEM produced by laser scanning methods. Due to the measurement principal, DEM from laser scanners are ortho-corrected from the beginning - outlines and roofs of buildings are always collocated.
The guidance, specifications, and standards should be applied to maps and map products, including but not limited to Flood Insurance Rate Maps and other maps, topographic (contour) work maps, flood profiles, and cross sections, developed from elevation and geo-positional data collected by LIDAR technology.
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