Seems like a small boat with radars that low to the water would have a short radar horizon?
I am not sure if the phase arrays you see there are radars. Phase arrays are also used for communication, and these can be used to link with other drones --- USVs and UAVs --- into a network. The SATCOM on the back appears covered and could have been changed. If you noticed there is a small dish like antenna on top of a mast with a camera, and that's the surface radar.