Planet WAP-7000 [28/29] Antenna cable

2 mile (3.2 km) 12.7 ft (3.9 m) 1 ft (0.3 m) 13.7 ft (4.2 m)

3 mile (4.8 km) 15.6 ft (4.8 m) 2 ft (0.6 m) 17.6 ft (5.4 m)

4 mile (6.4 km) 18 ft (5.5 m) 3 ft (0.9 m) 21 ft (6.4 m)

5 mile (8 km) 20 ft (6.1 m) 4 ft (1.2 m) 24 ft (7.3 m)

7 mile (11.3 km) 24 ft (7.3 m) 8 ft (2.4 m) 32 ft (9.7 m)

9 mile (14.5 km) 27 ft (8.2 m) 14 ft (4.3 m) 41 ft (12.5 m)

12 mile (19.3 km) 31 ft (9.5 m) 24 ft (7.3 m) 55 ft (16.8 m)

For example, the wireless link between the building A and the building B is located three miles (4.8

km) away. There is a tree-covered hill in the mid-way. From the table above, it can be seen that for

a three-mile link and the object clearance required at the mid-point is 5.4 m (17.6 ft). The

tree-covered hill height is at an elevation of 17 m (56 ft), so the antennas linkage on both sides

need to be at least 22.4 m (73 ft) high. The building A is six stories high or 20 m (66 ft), so the mast

or pole with 2.4 m (7.9 ft) must be constructed on its roof to meet the required antenna height. The

building B is only three stories high or 9 m (30 ft) but it is located at an elevation that is 12 m (39 ft)

higher than the building A. A mast or pole is required to mount an antenna at the required height

1.4 m (4.6ft) on the roof of building B.

5.3.2 Antenna Cable

An antenna cable introduces signal losses in the antenna system for both the transmitter and

receiver. To reduce signal loss, you should minimize the cable length and use only low-loss

antenna cable to connect your radio device to the antenna.

5.3.3 Weather Affection

The weather plays one of major matters to the antenna performance for the wireless

communication. The raining day, the lightning day, the cloudy day, or the windy day will make a

quite big impact to the both side antennas over the communication results. It will also cause the

communication quality unstable.

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