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Appendix 3 Points for Attention
1. Horizontal Direction and Angle of Pitch of Antenna
Since base station and wireless bridge adopt directional antenna, AP antenna on the base station
shall tilt down for certain angle. Meanwhile, AP shall align with client antenna.
2. Erecting Height of Antenna
Since the earth is spherical, wireless communication between two actual points places certain
requirements on the distance between two points and erecting height of antenna. For details, refer to the
following table.
Transmission
distance
3Km
5Km
10Km
15Km
5.8GHz
5m
7m
11m
16m
Appendix Table 3-1
3. Geographical Environment
The farthest communication distance is realized at sea level and clear open land; this is
geographical condition used to evaluate communication distance of wireless communication equipment.
It is followed by semi-clear and semi-open environment, such as suburb countryside, hills and riverbeds.
The nearest communication distance is realized at urban buildings or mountains. In one word, closer
obstacles exert greater effects on wireless communication distance; especially metal objects exert the
greatest effects. Therefore, during actual construction, try to make sure that client and AP are visible to
each other directly.
4. Electromagnetic Environment
DC motor, high-voltage grid, switching power supply, electric welding machine, high-frequency
electronic equipment, computer and single-chip microcomputer exert effects on communication distance
of wireless communication equipment to varying degrees.
