The illustration here appears to show the system on a Combat Boat 90 (CB90) which is only a 52 foot long boat. 

I don’t see an immediate need for this, but it is an interesting new type of radar sensor.

Naval Today reports Saab is offering, “…a 3D, active electronically scanned array (AESA) radar offering simultaneous surface and air surveillance capabilities,” and “…the entire system weighs less than 650 pounds (294 kilograms) in total, which makes it suitable for smaller patrol ships.”

Apparently they are thinking UAVs, “To combat the growing UAV (Unmanned Aerial Vehicle) threat, Sea Giraffe 1X features Saab’s Enhanced Low, Slow and Small (ELSS) surveillance function. This feature allows the radar system to detect and classify small, low-flying, slow-moving air targets.”

I suppose this might also be used to control small UAVs, putting them over surface targets of interest. The Coast Guard is looking at small UAVs.