Fresnel Clearance Zone

Distance1:	Miles
Distance2:	Miles
Frequency:	MHz
100% of F.C.Z.:	ft across to radius
60% of F.C.Z.:	ft across to radius

D1 = Distance from site1 to calculation point
D2 = Distance from site2 to calculation point

Note: When calculating F.C.Z. from site1 to site2
you have to consider D1=D/2 and D2=D/2

What is "Fresnel Zone" ?