Weissberger's model


Weissberger’s modified exponential decay model, or simply, Weissberger’s model, is a radio wave propagation model that estimates the path loss due to the presence of one or more trees in a point-to-point telecommunication link. This model belongs to the category Foliage or Vegetation models.

Applicable to/under conditions

  • This model is applicable to the cases of line of sight propagation. Example is microwave transmission.
  • This model is only applicable when there is an obstruction made by some foliage in the link. i.e. In between the transmitter and receiver.
  • This model is ideal for application in the situation where the LOS path is blocked by dense, dry and leafy trees.

Coverage

Frequency: 230 MHz to 95 GHz
Depth of foliage: up to '''400 m'''

History

Formulated in 1982, this model is a development of the ITU Model for Exponential Decay.

Mathematical formulation

Weissberger’s model is formally expressed as
where,
L = The loss due to foliage. Unit: decibels
f = The transmission frequency. Unit: gigahertz
d = The depth of foliage along the path. Unit: meters

Points to note

  • The equation is scaled for frequency specified in GHz range.
  • Depth of foliage must be specified in meters.

Limitations