Inmarsat have full global coverage on L-band (except in Antarctica and the North Pole). KA-band is still a bit difficult and expensive on a small vessel as it’s

Inmarsat have full global coverage on L-band (except in Antarctica and the North Pole). KA-band is still a bit difficult and expensive on a small vessel as it’s currently dependent on very expensive steerable antennas. There’s also Iridium.