The general equation for calculating the clearance zone radius at any point P in the middle of the link is the following:

where,

F_{n} = The nth Clearance Zone radius in metres

d_{1} = The distance of P from one end in metres

d_{2} = The distance of P from the other end in metres

λ = The wavelength of the transmitted signal in metres

The cross section radius of the first Clearance zone is the highest in the center of the RF LoS which can be calculated as:

where

*r*=__radius__in feet*D*= total distance in__miles__*f*= frequency transmitted in__Gigahertz__.

Or even:

where

*r*= radius in metres*D*= total distance in__kilometres__*f*= frequency transmitted in gigahertz.