https://www.inmarsat.com/en/solutions-services/maritime/serv...
Or Globalstar.
https://www.globalstar.com/en-us/blog/articles/satellite-sol...
there is zero globalstar mid ocean coverage.
there is a reason you will see lots of competing options for people integrating the iridium embedded modems into things designed to go on top of $40 million business jets and just about zero globalstar.
It was for his Spidertracks[1] flight tracking system. (Which, with the ADSB track, helped us hone in on the possible location. The wreck ended up being right in line with the last few pings.
[0] https://lompocrecord.com/news/local/experienced-solvang-bush...
one thing iridium has actually done really well is provide the developer documentation to make this fairly straightforward, there's a set of 600 page PDF files with every detail you could possibly need to make a very tiny embedded linux system talk to an iridum modem over a UART.
They're another example of exorbitant fees for tiny bits of data. (Though, being able to text pretty much anywhere on the globe on a tiny device is really nice - even with a 20minute RTT.)
I'd expect most of them to go with one of the Ka band these days; they have pretty small antennas available these days as far as I know.
you can fairly easily integrate iridium into something as small as a cessna 172...
at the minimum iridium will provide the ability to make phone calls to/from the PSTN while in the middle of an ocean on its smallest terminal. go up in terminal size a bit and you get something good for 500kbps of data.
for very large business jets that would be crossing the atlantic or pacific, that's a different market (overlaps somewhat with the same aviation VSAT terminals you would see on a 737-900 MAX)
