the general idea is that it is unhealthy to be right in the beam of a high-power air search radar. when you are in port, you get used to lots of pierside announcements to the effect of "do not rotate or radiate any electrical or electronic equipment while men are working aloft [in the masts of a ship at this pier]."

on most ships, the air search radars are on masts or platforms well above where any people work while underway. but on US AEGIS ships (CG 47, DDG 51), the pilothouse is located above the phased array panels. however, all of the arrays are on the outside of the blocky superstructure, pointing AWAY from the pilothouse. (there was a quote in that message about not leaning over the rails when standing on the bridge wings!)

the navantia design and derivatives (including the Nansens) did not take up this idea. presumably because they're smaller and needed the stability, but i'm just guessing there.