Page "Fresnel zone" Paragraph 18

The cross sectional radius of each Fresnel zone is the highest in the center of the RF LoS, shrinking to a point at the antenna on each end.

For practical applications, it is often useful to know the maximum radius of the first Fresnel zone.

From the above formula, the following formulas can be derived, using,, and.

Now we have an easy way to calculate the radius of the first Fresnel zone ( F < sub > 1 </ sub > in the above equation ), knowing the distance between the two antennas and the frequency of the transmitted signal.