The MDA is looking about upgrading its interceptors to handle a missile penetrating with decoys and other penetrating aids.
While this technology sounds difficult and complex, basically it’s just this:
Aluminum coated mylar balloons. What’s more, it’s entirely possible to put the warhead inside balloon, as was stated by a WMD experts years ago (can’t dig up the link, I think that he was from MIT).
Lockheed and Raytheon are competing for the contract. (Paid subscription required) They are taking two different design approaches.
Raytheon is developing multiple vehicles that are largely autonomous, and the number can be therefore be taylored to the size of the payload bay, with the first vehicle ejected serving to direct the others:
Lockheed has a “bandoleer” of smaller interceptors grouped around a central “mother ship”, which, while less flexible as to payload size, allows for a better sensor, and more maneuverability, for the initial contact and tracking with the kill vehicles being dispensed relatively closer to the interception point:
According to this article(paid subscription required), Lockheed’s sensor on the carrier will have 4x the resolution, 512×512 pixel staring array, as versus Raytheon’s 256×256 staring array.
Of course, these things look to cost a few hundred thousand bucks a pop, and I can get a silver mylar balloon for a buck fifty from the party store.