Nortel DCT1900 Technical Product Manual page 118

Technical Product Manual - DCT1900
Configuration Directions, Base Station Planning
4. Measure horizontal range on floor below, see Figure 3–2, (3).
Go to the floor below, leaving the Base Station on its current location and measure the
horizontal coverage again.
Note:
If the building is quite transparent to radio signals, the vertical coverage can reach to another floor
above and below.
In this way the horizontal and vertical coverage of a single Base Station in a typical area is found.
The cell size found can be taken as an average and used to calculate the total number of Base
Stations. From Figure 3–2 it is clear that three Base Stations can cover a building as seen in
Figure 3–1.
Depending on the size of the building and the type of construction, one or two more "random
checks" in typical areas can be done to verify the first measurement. The typical cell size is then
found by averaging the values.
=
5. Making a plan
- With the "typical cell size" found, make a sketch of all Base Station positions on the floor
plan. Indicate the expected coverage for each Base Station on the map.
- Verify with the Site Survey Tool if the real coverage is as expected from the map.
- Especially verify coverage in difficult areas such as elevators, stairways and
discontinuities in construction.
- If weak areas are found, see if re–positioning of Base Stations solves it; otherwise, plan an
extra base station.
- Take into consideration that in free space, with antennas in upright position, the coverage
is horizontal more than vertical. Although in normal office environments this effect is
negligible due to the amount of reflections, it still may be worth trying to place Base
Stations horizontally in order to get more vertical coverage such as in stairways.
3-4
Base Station of Demo Case
Fig. 3–2 Measurement of Typical Cell Size
132 ft.
2
1
3
1= 132 ft.
2= 66 ft.
3= 66 ft.
11.4 ft.
Config-DCT1900/R8/mw
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