How do I request a new satellite to be added to the list?

SatNOGS
1

I would like Inmarsat 4-F3 33278 to be added.
It was being used by Outernet 2.0, but still carries some interesting data.

Why: The Inmarsat satellites are geosynchronous and have a very strong signal that can be received with fixed a 3 element patch antenna, an RTL-SDR with an LNA. These are useful in proving that a setup is working and adds L-Band to the mix of satellite possibilities.

Inmarsat 4-F1 28628 is already in the database. https://db.satnogs.org/satellite/28628/

The other one in the series is Inmarsat 4-F2 28899.

–Konrad, WA4OSH

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Oh crap… what happens when somebody schedules a pass with a satellite that is always visible??? Will it occupy the ground station 24/7? :smile:

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good point… I just tested Inmarsat 4-F1 in dev and its not showing up in pass predictions nor can you manually schedule it. This is likely in the way we use pyephem’s next_pass() call which is going to try to calculate the next rise time - which in this case never happens… I went ahead and filed an issue for this but its not going to be an easy fix: https://gitlab.com/librespacefoundation/satnogs/satnogs-network/issues/471

In addition, I notice the ground track map is broken in db for Inmarsat 4-F1… I filed https://gitlab.com/librespacefoundation/satnogs/satnogs-db/issues/214 for this.

@WA4OSH thanks for bringing this up, previously nobody has asked about or tried one of the GEO birds… I can add F3 to the db, but its unlikely to be supported by satnogs-network anytime soon. :frowning:

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Alphasat and Inmarsat-4 satellites are Geostat on L-band.
I-4 F1 Asia-Pacific, at 143.5 degrees East.
I-4 F2 EMEA (Europe, Middle East and Africa), at 63.9 degrees East.
I-4 F3 Americas, at 98.4 degrees West.

So, of course, they are always visible.

Their tracks 4-F1 4-F2 4-F3 may look “broken”, but remember, they are Geostat and not Geosync. It’s a weird analemma for people that have been looking at LEO’s. They will appear to go up and down around a fixed spot over a day.

This may cause problems for the ephemera? programs, but really should not present a problem for a ground station to track and receive one.

All it takes to receive these birds is an RTL-SDR, a two or three element 4 inch-square patch antenna and an LNA. (or an active patch antenna).

There should not be any reason why satellites with “weird” orbits, or up to L-Band can’t work with the standard SatNOGS setup. The Highly Elliptical Orbit (HEO) or Tundra satellites E.g. SiriusXM, Molniya present a similar problem.

Why should SatNOGS be limited to LEO’s? Why should SatNOGS be limited to VHF and UHF, when the hardware is good up to SHF/L-Band?

You might want to limit the length of an observation of birds that perpetually appear up in the sky.

–Konrad, WA4OSH

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Its a software limitation at this point. It assumes an orbit will rise and set over a ground station.

We support this, as soon as ground stations show up that support other bands (I think we may have some already that can RX S-Band in prod)…

Cheers!

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Corey,
Thanks!
L-Band is a no-brainer. I have a Patch antenna, NooElec Saw Filter & LNA … or an SDRx from the days of Outernet
2.0.

I also have an Outernet moRFeus. That will allow me to down-band frequencies up to 6 GHz into a range that can be received with an ordinary RTL-SDR.

Let me know when the “feature” of allowing a satellite that does not rise and set is there.

–Konrad, WA4OSH

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Incidentally, I found this article about what’s on the L-Band to be very interesting:
L-band: L-band reception frequencies and techniques

–Konrad, WA4OSH

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