Radio coverage calculator for surface propagation

Surface radio propagation example.


This service provides calculation of surface propagation of radio waves depending on frequency, emitted power and antenna heights.

The data here may change or be removed whenever I feel like it, so if your preferred data has disappeared it's your fault for not downloading and saving it.

KMZ Files
The KMZ files are intended to be used in Google Earth.

Be aware that not all files found here of radio sites with patterns depicts actual sites, just theoretical sites. Other factors may apply as well rendering the patterns inaccurate.

Request calculation

Results may be found in public folder. The files are in folders for different areas of the map, first for every 10 degrees and then sub-folder for every degree. Name is based on frequency and coordinates. Be aware that it can take several minutes before a request is processed.

Hint: To get the coordinates right, use Google Earth, put a placemarker, then copy the Latitude and Longitude values into the web form. Make sure that you have Google Earth set to English language first or you may have to edit to W/E/N/S for the direction.

Frequency (MHz) Permitted range is 20 MHz to 2000 MHz.
(DD°mm'ss.dd"N |)
Permitted latitude/longitude formats:
  • DD°mm'ss.dd"X (X is any of N, S, W or E)
  • DD°mm.dd'X (X is any of N, S, W or E)
  • DD.ddddddX (X is any of N, S, W or E)
  • [-]DD.dddddd
Negative values for South and West.

HMS 57°40'51.04"N 57°40'51.04"S 12°40'51.04"E 12°40'51.04"W
HM.d 57°40.54'N 57°40.54'S 12°40.54'E 12°40.54'W
Decimal with Direction 57.680844N 57.680844S 12.680844E 12.680844W
Decimal without Direction 57.680844 (for North or East)
-57.680844 (for South or West)

Tx Antenna Height (m) This is the height above ground in the selected location. Ground height over mean sea level is computed from a database.
Rx Antenna Height (m) This is the estimated height of the antenna receiving the signal.
Radiated power (W erp) Radiated power is NOT the power the transmitter has but what the antenna radiates!
The Rx dB Threshold is the minimum required value for the receiver to be able to detect the signal.
Use this Excel sheet to help calculating the values: ErpCalc.xls
Rx dB Threshold (dbμV/m)
Old ITM algorithm New ITM algorithm considers obstructions, but seems to have bugs at the moment.
Radio Climate Radio Climate factors.
Graph Type Graph color and transparency, monochrome have increased transparency for weaker signal.
Description (max 80 chars)