https://elecraft.com/products/kx2-ssb-cw-data-80-10-m-transc... is the de-facto backpacking HF rig, usually the inreach[1] and similar are good enough for most people and doesn't require a license (just subscription).

[1] https://explore.garmin.com/en-US/inreach/

Amateur radio equipment in the so-called HF band can get you non-line-of-sight transmission. You'll need a really big antenna, and you'll need to be content sharing a few hundred kHz of spectrum with everyone else on the same continent.

"Big" doesn't necessarily mean "heavy" or "bulky" though. A decent length of lightweight wire and a tree can get you a very long way.

You can have a lot of contacts with a pretty minimal wire antenna, such as a dipole.

In the US, if you have a General class ham radio license, you could do it on the 7Mhz frequency if your antenna is relatively close (less than 1/4 wavelength) to the ground. See https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&c...

At higher frequencies (such as the 432 MHz used in this trans-Atlantic contact), the radio waves will not be reflected by the ionosphere and will disperse.

I think Inmarsat makes a nice little unit ;)