DTED
DTED (or Digital Terrain Elevation Data) was originally developed in the 1970s to support aircraft radar simulation and prediction.
DTED supports many applications, including line-of-sight analyses, terrain profiling, 3-D terrain visualization, mission planning/rehearsal, and modeling and simulation. DTED is a standard NGA product that provides medium resolution, quantitative data in a digital format for military system applications that require terrain elevation.
The DTED format for level 0, 1 and 2 is described in U.S. Military Specification Digital Terrain Elevation Data (DTED) MIL-PRF-89020B, and amongst other parameters describes the resolution for each level:
- Level 0 has a post spacing of 30 arcseconds in latitude direction (ca. 900 meters)
- Level 1 has a post spacing of ca. 90 meters which results in the follwoing table
| Zone | latitude | interval latitude (arc sec) | interval longitude (arc sec) |
|---|---|---|---|
| I | 0°-50° (North-South) | 3 | 3 |
| I | 50°-70° (North-South) | 3 | 6 |
| I | 70°-75° (North-South) | 3 | 9 |
| I | 75°-80° (North-South) | 3 | 12 |
| I | 80°-90° (North-South) | 3 | 18 |
- Level 2 has a post spacing of 1 arcseconds (ca. 30 meters)
In addition three more levels (3, 4 and 5) at increasing resolution have been proposed, but not yet standardized.
Many DTED data is generated from SRTM data.
External links
- DTED at FAS.org
- MIL-PRF-89020B — DTED specification