Unless I'm missing something, you don't say what charting / EN software you're using. This seems to be a top of the
line installation and tightly integrated, so the answer to the software / firmware question is important. MARPA is largely a
radar issue...YOUR
radar, not the target's and, unlike AIS, the number crunching horsepower necessary to develop and display that target's dynamics (speed, direction, CPA, TCPA, etc) is a function of your system, primarily your
radar and it's display. There should be a card or slot available in the unit to take care of that function alone and plenty of documentation to support it. The short of this answer is, look for evidence, printed or otherwise, that your
radar either has MARPA capability already or can get it. The Europeans are way, way ahead of us in ARPA and AIS technologies anyway, and I'd be surprised if your system can't put these two issues together.
You'll discover soon enough that AIS is the cat's meow when it comes to figuring out if other vessels pose a threat to you...much more information is provided to you than you can get from MARPA. The big difference is that MARPA data are derived, relative to you; AIS positional data are absolute, that is, developed from
GPS coordinates and transmitted to you constantly along with much other descriptive information pertaining to the vessel. What your software has to do is take all the available positional possibilities and put everything neatly on your display. From this answer, you might conclude, correctly, that the value of MARPA is vastly reduced if you have AIS, and I'd bet that your system can integrate AIS right now on your
radar display...but you may need to upgrade your charting software or firmware.
howard Keiper