Product manual

Configuration directions, Base station planning
Technical Product Manual - DCT1800-GAP
TD 92093 (1/LZBNB 103 108 R4D) / 2006-03-09/ Ver.C
© 2006
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3.6 Site survey
To satisfy area coverage and traffic demands, the site must be surveyed in order to determine the
number and position of base stations. To do a site survey, a site survey tool and ground plans of the
floors are required. With help of these tools a proper base station planning can be made. Samples
must be taken to determine an average cell size. With the average cell size, base station positions
can be indicated on the map, together with the area covered by each base station. Also difficult spots
can be mapped. After this, the planned positions can be verified with the site survey tool and with help
of the traffic requirements a final plan can be made.
For the use of the site survey tool, refer to the ‘DCT1800 Site Survey Tool User’s Guide’. The principle
of a site survey is as follows:
Observe the building to find a ‘typical area’
Modern buildings usually have standard constructions. In older buildings, due to renovations or
expansions, areas with different structures may exist. However, inside these areas a uniformity in
structure can be found again.
Find an area with a typical structure for the building and of about the expected cell size. This area will
be used to determine the typical cell size. When having a building with different structures, do so for
each of those areas, so that differences in ‘typical cell size’ can be detected.
Measure the horizontal cell size on the middle floor, see (1) in figure 4
The cell size can be determined as follows:
1. Install the site survey base station in the middle of the ‘typical area’.
2. Walk away from the base station with the cordless phone. Also enter rooms to the left and right.
3. Determine the edge of the cell by means of the limit warning or by looking to the LinkInfo display
and listening to the sound quality (see the ‘DCT1800 Site Survey Tool User’s Guide’).
4. Do the same in the opposite direction.
5. This is the horizontal coverage on the floor of the base station.
Measure horizontal range on floor above, see (2) in figure 4
Go to the floor above, leaving the base station on its current location and measure the horizontal
coverage here.
Measure horizontal range on floor below, see (3) in figure 4
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, used to calculate the total number of base stations. From
figure
4 it is clear that Three base stations can cover a building as in figure 3. 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.