RadioPlanner 3.0 Update 260630

We have updated the ITU-R P.1812 propagation model to the latest version, P.1812-8. The update includes the ability to choose between the Deygout method (used in earlier versions of Recommendation P.1812) and the Delta-Bullington method (used in the latest versions of Recommendation P.1812) for diffraction loss calculations. This allows users to calculate coverage areas more accurately by taking terrain characteristics into account.

The table below summarizes the conditions under which each diffraction loss calculation method is preferred.

Condition	Deygout method advantage	Delta-Bullington method advantage
Several sharp terrain obstacles (multiple knife edges)	✅ Better — identifies the dominant obstacle and recursively accounts for secondary obstacles	May simplify the path too aggressively
One dominant ridge with smaller surrounding obstacles	✅ Often more accurate	Usually gives similar results
Deep shadow regions behind mountains/ridges	✅ Better representation of multiple-edge diffraction	Can underestimate or smooth losses
Smooth terrain with no clear dominant obstacle	Little advantage	✅ More stable and realistic
Long paths with many small hills	Often overestimates because it treats secondary edges recursively	✅ Better average prediction
Mixed terrain with irregular clutter	Limited benefit	✅ More suitable