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Multi-Layer Fieldstrength Prediction
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The penetration
of electromagnetic waves into buildings is very important for the
planning Mobile WiMAX
networks. Even more important are combined
simulation
scenarios with indoor and outdoor predictions.
Very often the antennas of the base stations are located on the
roofs of buildings. And the network planning for the users inside the
surrounding buildings is required.
This is a big challenge for propagation models, because urban building data (incl. topography) as well as indoor vector data must be
considered during the simulation.
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WinProp
is able to handle this challenge with two different approaches
depending on the databases available:
- Empirical indoor propagation models (without
consideration of indoor walls).
This should be selected if no
information about the walls inside the building is available and if a
coverage prediction inside the building is required.
- Combined
network planning
(CNP)
(including
indoor walls).
This should be selected if information about
walls and objects inside the building is available.
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Example for Mobile WiMAX Indoor Coverage Analysis
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An example
for an indoor coverage analysis in a combined simulation scenario is
shown in the following
figures.
Figure 1
shows the simulation scenario.
The wave
propagation for a mobile WiMAX transmitter in the 3.5 GHz frequency
band
is simulated. The WiMAX base station antenna is located close to a multi floor office building.
The antenna is mounted 25 meters above the ground
and has a downtilt of two degrees. The transmitter power is 43 dBm.
For each pixel in the scenario database the
field strength (path loss) is predicted. WinProp is able compute
simultaneously on multiple prediction heights for indoor scenarios (even
if used in combined
urban/indoor scenarios).
In this example, the field strength (path loss) is predicted 1.5 meters
above the
ground in the streets. Additionally, the path loss inside the office
building is predicted on all
three floors (1.5m, 6.5m and 11.5m above street level).
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Figure
2: 2D view of the Field strength
prediction in a combined scenario.
Figure 2
shows the the
field strength on the ground floor of a multifloor
office building (in the center of figure 2, prediction inside building
computed with CNP => incl.
indoor walls) and the
field strength prediction on the ground floors of all other buildings
(predicted with empirical indoor coverage models => without indoor
walls).
Indoor fieldstrength
prediction is very useful for the planning of mobile WiMAX
applications, especially for large office buildings or shopping centers
with
multiple floors. WinProp offers highly accurate indoor prediction
results on several building floors simultaneously.
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Figure 3a:
Field strength prediction on ground floor
(1.5 meters above
street level) |
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Figure 3b:
Field strength prediction on 2nd floor
(6.5 meters above street level) |
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Figure 3c:
Field strength prediction on 3rd floor
(11.5 meters above street level) |
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Figure 3
shows the advantages of indoor field
strength prediction on multiple heights. The received field
strength on
the ground floor of the building (see figure 3a) is below 85
dBµV/m. The mean value of the field strength on
the ground floor is
78.2 dBµV/m.
On the second floor (figure 3b), the mean field strength
predicted
is 82.8 dBµV/m.
The situation improves even more on the third
floor (figure 3c), where
the mean field strength is 90 dBµV/m.
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Download
a
presentation about WiMAX Network Planning
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