If you look at pictures of the Zumwalts putting around, you'll see they have standard naval radars mounted atop the deckhouse. Also, with stealth aircraft it's

If you look at pictures of the Zumwalts putting around, you'll see they have standard naval radars mounted atop the deckhouse. Also, with stealth aircraft it's common practice to attach reflectors when not on a mission to go blow someone up. I imagine it's the same for the ships.