252km at sea level!

Hi
I had a ttnmapper enabled node mounted on the roof of my car when driving around in the south east of Sweden. At one time a couple of packages were picked up by a gateway nearby Gdansk in Poland 252km away!? Should this even be possible? My node was at sea level, and I assume that the gateway wasn´t airborne.

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In addition to this, some packages were also picked up by a gateway in Simrishamn ( 132km away )

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It only happened once, I tried to repeat it the next day without success.
Anyone seen this before? Any atmospheric phenomena or something that made this possible? Weather?

It happens ocaisionally, yes.

Aside: looking at all results for a gateway may give some clue if its coordinates are set okay. It seems they are okay:

TTN Mapper

Same goes for the other one:

TTN Mapper

As for atmospheric phenomena, see Did we just prove the world isn't flat? or maybe it is and Weird result during ttn mapping.

Hi @LinusEricsson, assuming no fakery, it’s likely that this was due to transient Tropospheric Ducting.

Also search on Google Images for “tropo scatter”. It’s widely used for long-distance low-capacity radio and much-loved by military but is very unpopular with regulators.

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We published a paper on this type of propagation using TTN. Check the pre-print here: https://arxiv.org/pdf/2004.02802.pdf

Thanks for sharing info about your long link!