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Radio propagation: Difference between revisions
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The result is signal attenuation in dB along the direct path. The ITM functions will determine for us if the radio propagation is line-of-sight, diffraction dominant or tropospheric scatter. For diffraction propagation, it also determines if it's single horizon or double horizon. | The result is signal attenuation in dB along the direct path. The ITM functions will determine for us if the radio propagation is line-of-sight, diffraction dominant or tropospheric scatter. For diffraction propagation, it also determines if it's single horizon or double horizon. | ||
This information will further be used in calculating ground clutter obstruction for different terrain types. The most frequent obstructions that affect radio signals are built-up areas and tall vegetation. By calculating the interference of ground clutter inside the first Fresnel zone, we can determine signal losses with average precision. | This information will further be used in calculating ground clutter obstruction for different terrain types. The most frequent obstructions that affect radio signals are built-up areas and tall vegetation. By calculating the interference of ground clutter inside the first Fresnel zone, we can determine signal losses with average precision. | ||
In order to do so, we need two more factors in the equations: clutter height above terrain, and clutter density. These | In order to do so, we need two more factors in the equations: clutter height above terrain, and clutter density. These are hardcoded, at least for a number of terrain types, but can also be stored into an easy to read Sqlite database, allowing for more terrain types and properties to be changed by the user. The aim is to make these two factors as configurable as possible to the user, in order to be able to adapt them to local measured conditions. | ||
The radio stations parameters are also completely configurable by the user, by setting internal properties, via Nasal scripting or otherwise. | The radio stations parameters are also completely configurable by the user, by setting internal properties, via Nasal scripting or otherwise. | ||
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* RF link budget calculations using transmitter power, receiver sensitivity, antenna gain and height above terrain, taking into account typical values from various specifications | * RF link budget calculations using transmitter power, receiver sensitivity, antenna gain and height above terrain, taking into account typical values from various specifications | ||
* experimental feature: usage of detailed landcover in RF propagation prediction (ground clutter path loss) | * experimental feature: usage of detailed landcover in RF propagation prediction (ground clutter path loss) | ||
* landcover radio properties are stored into an easy to read and modify Sqlite database, allowing for more terrain types and radio properties to be changed by the user | |||
* signal loss due to polarization mismatch | * signal loss due to polarization mismatch | ||
* simple signal strength indicator (Instrument for signal level reading) | * simple signal strength indicator (Instrument for signal level reading) | ||