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SPLAT (Signal Propagation, Loss, And Terrain) tool to create wireless network design and more... awe

MannDude

Just a dude
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I've been playing with SPLAT a bit lately to create predictive area coverage maps for some amateur radio stuff. It's a wonderful tool, made even greater with use of some bash scripts that a reddit user has created.


For starters, you can read more about SPLAT here: http://www.qsl.net/kd2bd/splat.html

SPLAT! is an RF Signal Propagation, Loss, And Terrain analysis tool for the electromagnetic spectrum between 20 MHz and 20 GHz.


Applications of SPLAT! include site engineering, wireless network design, amateur radio communications, frequency coordination, communication system design, and terrestrial analog and digital television and radio broadcasting.


SPLAT! provides site engineering data such as the great circle distances and bearings between sites, antenna elevation angles (uptilt), depression angles (downtilt), antenna height above mean sea level, antenna height above average terrain, bearings and distances to known obstructions based on U.S. Geological Survey and Space Shuttle Radar Topography Mission elevation data, path loss and field strength based on the Longley-Rice Irregular Terrain as well as the new Irregular Terrain With Obstructions (ITWOM v3.0) model, and minimum antenna height requirements needed to establish line-of-sight communication paths and Fresnel Zone clearances absent of obstructions due to terrain.


SPLAT! produces reports, graphs, and highly detailed and carefully annotated topographic maps depicting line-of-sight paths, path loss, field strength, and expected coverage areas of transmitters and repeater systems. When performing line-of-sight analysis in situations where multiple transmitter or repeater sites are employed, SPLAT! determines individual and mutual areas of coverage within the network specified. SPLAT! also produces .geo Georeference Information Files for interoperability with Xastir software, and .kml Keyhole Markup Language files for interoperability with Google Earth.

Sounds awesome, right? Well, it is. For my use I'm basically just following the instructions provided here ( https://github.com/molo1134/splat-scripts ) to produce what I want it to do. Your intended use of SPLAT may require a more comprehensive setup... so why not take a peak at the manual here: http://www.qsl.net/kd2bd/splat.pdf


I should warn you that the USGS satelite imagery/topography datafiles will take up quite a bit of space (9GB~) for a region like North America. Going to be more or less depending on where in the world you live.


I just chose a random point in the hills of southern Kentucky to generate the example below. Assuming an antenna capable of effective radiated power of 200w is mounted 20' above ground. The first example is the predictive range/coverage of this at the top of the hill. The second is predictive range/coverage if the exact same setup at the base/bottom of the hill in the valley.


Note: Images cropped as the images that are created by this script are 6,000X4830. So I've reduced them to 25% of their original size for this post.


KZ4AFmx.jpg


And the exact same details as before but with the antenna placed at the foot of the hill instead of ontop of it:


K6Jmq8I.jpg


Obviously the higher and more powerful the antenna, the better coverage.


Not really sure if y'all will get any use out of this, but I am having fun playing with it.


To get the coordinates of any particular location, I use: http://www.gps-coordinates.net
 
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