Fresnel Zones

The DK now brings Fresnel zone analysis for radio wave propagation purposes.

Class TGIS_Viewshed got a new method, GenerateFresnel, and a new property, Frequency. Generating grid data with Fresnel Zone clearance is as easy as:

viewshed = new TGIS_Viewshed(); 

viewshed.Frequeny = 100000000 ; // 100 Mhz
viewshed.GenerateFresnel(
  _dem, 
  _transmitters, 
  _clearance, 
  _zone_number, 
  _offset_dem, 
  _offset_field, 
  _offset_transmitter 
);

• _dem
  layer with digital elevation model;
• _transmitters
  layer with location of transmitters;
• _clearance
  output layer with pixel values varying between 0 and 100 (clearance in percents)
• _zone_number
  number of Fresnel zone for which calculation will be performed;
• _offset_dem
  value to be added to DEM (like forest height);
• _offset_field
  attribute field with transmitter elevation height offset;
• _offset_transmitter
  fixed transmitters height offset.

The computation result looks like:

See more in Documentation.