Ceragon FA4800, Руководство пользователя

Страница: 45 / 333

Stage 2: Physical Survey Chapter 2
FA4800 User Manual Release 1.9.30 2-3
8. Use the Link Budget Calculator (on the CD supplied with the equipment
or using the FibeAir2000 Manager) to determine the expected perfor-
mance.
Stage 2: Physical Survey
The physical site survey reviews the environment of the proposed installa-
tion location, to ensure that the link sites are suitable for the wireless net-
work. The results of the physical site survey should be recorded.
¾
To perform a physical survey:
1. From the compass readings taken in the preliminary survey, find the azi-
muth (horizontal position) that the ODU should face towards the second
ODU.
2. Using binoculars, locate any obstructions such as tall trees, high build-
ings, hills or mountains. Look for other RF towers between the two sites.
Mark the locations of the obstructions on the map.
3. Determine the location for the ODU (having regard for existing rooftop
installations and tower space). It should be above any obstructions, con-
sidering the Fresnel zone (see
21 ).
4. If you need to install the ODU on a tower, make sure that the tower is far
away from overhead electric power lines.
5. Determine a location for the indoor equipment; it should be as close as
possible to the ODU. At an existing site, there is probably an equipment
room with cable-routing channels.
6. Measure and record the path length of the cable from the ODU position
to the indoor equipment room.
7. Determine the ground and lightning connection points of the installation.
The ODU and IDU must both be grounded.
8. Using the Ohmmeter, measure and record the resistance of the required
installation to the grounding point. The resistance must be less than 1O
ohm.
9. Review the results of the physical site survey. Decide if the site is suitable
for the wireless network installation.
• If the site is suitable, continue with stage 3, the RF survey
• If the site is not suitable, survey another site
Note
It is advisable to go on a clear day, so you can more easily see any
obstructions between the two sites.
Note
The IDU - ODU cable length limit is 100m, in accordance with IEEE 10/
100BaseT standards.