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Propagation
of electromagnetic waves in urban areas in the frequency range above
300 MHz is influenced mainly by the buildings. Therefore a detailed
vector database of the buildings is required. For frequencies below 300
MHz, the suburban propagation models can be used even in urban
environments.
Typically the multipath propagation is very important in urban
environments (see figure). Simple empirical propagation models are
therefore not sufficient.
The
urban propagation models can be used for cellular network planning as
well as for LOS analysis (microwave links). Antennas can be mounted
below the rooftop level or above (if they are mounted below this leads
to microcells).
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This is a typical urban propagation environment with some propagation
paths.
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