SPACEX STARLINK

[WB4WZI]

Good morning,
I am working on a project looking at Ku carrier signals of LEO satellites. We are looking how the signal propagates through the atmosphere.
We would like to us the Starlink satellites to accomplish this. The question I have is...Has anyone used a Ku feed and reflector (not starlink equipment) to look at these signals? If so, what did you use? We have been trying to use a Ku feed horn connected to a spectrum analyzer and not having any success of seeing anything.

Any help you could provide would be greatly appreciated.

Thank you,
Lee

 

[thebaldgeek]

Have you been following Scotts work on this?

https://twitter.com/i/web/status/1510410724899639298

Derek has also been doing some great work on it.

Receiving Starlink satellite beacons on a budget

Next article: Hard-wiring an LNB to use the high band 10.6 GHz oscillator

sgcderek.github.io

Ben

 

[prcguy]

All the research your looking to do has already been done and should be published somewhere. I've monitored Ku geostationary sats for probably 30yrs taking precise beacon data 24/7 from various look angles of 10deg off the horizon to about 50 deg off the horizon. There should be little difference in atmospheric data between geostationary and LEO as long as you compare the same look angles.

Bottom line is rain does attenuate Ku and during huge downpours I've seen upwards of 30dB attenuation briefly at a 47deg look angle. Gentle rain no big deal, maybe a dB or so fade and heavy rain maybe 6-10dB. Looking through thick black rain clouds maybe a dB loss. Dense fog a fraction of a dB.

Another problem you can have is scintillation and tropo ducting at low look angles. That can cause big fade outs when ducting is happening like 10dB or more. Its all dependent on where the rain is falling and rain 5mi away can be causing a big fade when there is no rain over your head. It depends on what the antenna is looking through. With lots of LEOs floating around I would suspect a receiver on the ground can see several at any given time and if a huge amount of rain dumps and attenuates one satellite there may be others more in the clear.

Good morning,
I am working on a project looking at Ku carrier signals of LEO satellites. We are looking how the signal propagates through the atmosphere.
We would like to us the Starlink satellites to accomplish this. The question I have is...Has anyone used a Ku feed and reflector (not starlink equipment) to look at these signals? If so, what did you use? We have been trying to use a Ku feed horn connected to a spectrum analyzer and not having any success of seeing anything.

Any help you could provide would be greatly appreciated.

Thank you,
Lee

 

[WB4WZI]

Thank you for the info. Have not been following him but I will.

All the research your looking to do has already been done and should be published somewhere. I've monitored Ku geostationary sats for probably 30yrs taking precise beacon data 24/7 from various look angles of 10deg off the horizon to about 50 deg off the horizon. There should be little difference in atmospheric data between geostationary and LEO as long as you compare the same look angles.

Bottom line is rain does attenuate Ku and during huge downpours I've seen upwards of 30dB attenuation briefly at a 47deg look angle. Gentle rain no big deal, maybe a dB or so fade and heavy rain maybe 6-10dB. Looking through thick black rain clouds maybe a dB loss. Dense fog a fraction of a dB.

Another problem you can have is scintillation and tropo ducting at low look angles. That can cause big fade outs when ducting is happening like 10dB or more. Its all dependent on where the rain is falling and rain 5mi away can be causing a big fade when there is no rain over your head. It depends on what the antenna is looking through. With lots of LEOs floating around I would suspect a receiver on the ground can see several at any given time and if a huge amount of rain dumps and attenuates one satellite there may be others more in the clear.

Thank you this helps also