Was surfing the net and came across this picture (source here)….
This is the ROKN Chamsori (Sea Dolphin)-class patrol boat PKM-259 (also seen here). The photo was apparently taken in Cheju Do (the large island to the south of the Korean peninsula).
The item of interest is what looks to be a SATCOM antenna on the deck aft. The antenna replaces an enclosed single 20mm Gatling/Vulcan mount (like the one atop the superstructure).
Again looking at other pictures at the source, this boat may be a command & control ship for a small flotilla (three boats).
Is it worth giving up one of three mounts for this mode of communications?