Spanish cell carriers rambling
some years ago, Renfe announced a partnership with Telefónica to offer free wifi in their AVE trains, putting 4G (and now 5G I assume) antennas in the trainsit sounds cool, doesn't it? well, they didn't spare a single minute in thinking about keeping that working while in a tunnel. it works perfectly overground, but the second the train enters a tunnel, internet is gone
in Barcelona, the only H.S. track crossing the city (so, the one essentially every single AVE train in the city goes through) has absolutely zero cell reception, not even for the train modems.
there has to be a way of forcing carriers to actually ensure proper service, it's 2025, on a technical level this is a solved problem. they clearly just don't care and have realized they can get away with it, free market competition obviously didn't work either because no carrier has reception. either that, or is ADIF blocking the installation of that infrastructure? but why would they?