SMC Networks 2.4GHz/5GHz manual 3-4

Bridge Link Planning
3-4
.
Note that to avoid any obstruction along the path, the height of
the object must be added to the minimum clearance required for a
clear radio line-of-sight. Consider the following simple example,
illustrated in the figure below.
Total Link
Distance
Max Clearance
for 60% of First
Fresnel Zone at
5.8 GHz
Approximate
Clearance for
Earth
Curvature
Total
Clearance
Required at
Mid-point of
Link
0.25 mile (402 m) 4.5 ft (1.4 m) 0 4.5 ft (1.4 m)
0.5 mile (805 m) 6.4 ft (1.95 m) 0 6.4 ft (1.95 m)
1 mile (1.6 km) 9 ft (2.7 m) 0 9 ft (2.7 m)
2 miles (3.2 km) 12.7 ft (3.9 m) 0 12.7 ft (3.9 m)
3 miles (4.8 km) 15.6 ft (4.8 m) 1.8 ft (0.5 m) 17.4 ft (5.3 m)
4 miles (6.4 km) 18 ft (5.5 m) 3.2 ft (1.0 m) 21.2 ft (6.5 m)
5 miles (8 km) 20 ft (6.1 m) 5 ft (1.5 m) 25 ft (7.6 m)
7 miles (11.3 km) 24 ft (7.3 m) 9.8 ft (3.0 m) 33.8 ft (10.3 m)
9 miles (14.5 km) 27 ft (8.2 m) 16 ft (4.9 m) 43 ft (13.1 m)
12 miles (19.3 km) 31 ft (9.5 m) 29 ft (8.8 m) 60 ft (18.3 m)
15 miles (24.1 km) 35 ft (10.7 m) 45 ft (13.7 m) 80 ft (24.4 m)
17 miles (27.4 km) 37 ft (11.3 m) 58 ft (17.7 m) 95 ft (29 m)
AB
3miles(4.8km)
5.4m
17m
20m
2.4m
12m
9m
1.4m
Visual Line of Sight Radio Line of Sight