[TowerTalk] Where to get HFTA Software

[Jim Lux]

On 3/4/12 12:44 AM, Mark Robinson wrote:
> What is SRTM . DEMS and DTED

SRTM - Shuttle Radar Topographic Mission - THey built a precision 
interferometric Synthetic Aperture Radar that mounted in the shuttle's 
cargo bay and had a 60m(?) boom sticking out, with precision metrology, 
to hold a second antenna.

They basically mapped most of the earth's non-polar area surface at an 
accuracy finer than 10meters horizontal resolution, 1 meter vertical 
resolution. Quite an achievement in many ways.  (the proverbial 
truckload of data tapes were brought back down, and they spent several 
years processing them)

DTED - Digital Terrain Elevation Data  - gridded elevation data at a 
specified precision and resolution

DEM - Digital Elevation Model - essentially the same thing, gridded 
elevation data  Historically, USGS produced DEMs and DoD produced DTEDs.

The grids are either "fixed distance between posts" (e.g. 30meters) or 
"fixed angle between posts" (e.g. 1 arc second of lat/lon).





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> Mark N1UK
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