Tropospheric effect with different wavelengths

Orekit Python Wrapper usage
1

Hello!

I am trying to see the effects of the atmosphere on a radio signal. My idea is to see how a signal gets attenuated and delayed (varying the signal frequency and power levels). Is there a straightforward way to do this in Orekit?

My first idea was to consider the ionosphere and the troposphere. For the troposphere, I was targeting the ITURP834 model

tropo_model = ITURP834PathDelay(TimeScalesFactory.getUTC())
tropo_delay = tropo_model.pathDelay(tracking_coordinates, point, pressure_temperature_humidity, tropo_model.getParameters(date), date).getDelay()

Assuming I can retrieve some reasonable values for the pressure_temperature_humidity, it is still not clear to me where I can play with the signal frequency and power. Could you help me in this, please?

Many thanks and best regards,
Samuele

2

You can retrieve pressure temperature and humidity from GlobalPressureTemperature3. This will of course only be mean values, but it takes into account position and date.
Tropospheric effect is frequency-independent up to a certain extent (i.e. there are models for radio frequencies or for optical frequencies, but nothing beyond that). What depends on frequency is ionospheric effect, and its pathDelay method takes a frequency argument.
Power has no effect on the delay either, it has only an effect on the global link budget.

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Hi Luc,

Thank you so much for your reply. I will take a look at the GlobalPressureTemperature3. Regarding the power, I was indeed interested in studying the global link budget!

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