Data Point Accuracy

RF Profiler using the Google Elevation database for its terrain data. This database consists of SRTM data plus a number of other geospatial sources. SRTM data consists of Space Shuttle radar snapshots of the earth at a given interval. The majority of the worlds publicly available data is three arcsecond accurate (90m) with the continental US being one arcsecond accurate (30m).

The number of datapoints created for your profile will be the distance of the link divided by the accuracy selected. Maximum 5000 datapoints per link. Between each datapoint, the elevation is averaged. Drastic changes in elevation are not always reflected in terrain data, therefore verification through site visits is highly recommended.

When selecting the accuracy value, use the following guidelines

1. 1. Google currently limits the number of daily data point requests to 25000. A Database Request error will appear in the number of daily requests is exceeded. 
   

2. 2. On a new link, select a lower accuracy to begin with and then increase as needed.
   

3. 3.When a link is outside of the US, use 100m or 500m accuracy.
   

4. 4.When a link is inside of the US, 30m and 10m accuracy will usually only show improvements in major cities.
   

5. 5.Changing Data Point Accuracy will regenerate the link. Ground cover values will need to be reentered.