Bobmary37 (et.al.),
CLARIFICATION: Want to make sure these comments (my comment) do not send you down a rabbit hole nightmare.
First, the fact of needing a static IP stands. A must have.
However, even with a static IP, using UDP transport for time sensitive data over a satellite link is likely to cause male pattern baldness quickly!
UDP is a "best try" only protocol, and throw in a satellite link, and trying to transport time sensitive data, such as voice, is a recipe for serious frustration. Tread very cautiously.