http://www.cpf.navy.mil/news.aspx/010279
To explain in simple terms, a shipboard device generated carbon-fiber particles suspended in a cloud of smoke, which can absorb or diffuse radar waves emanating from the seekers of incoming missiles and potentially obscure the target from the missile. The experiment demonstrated maritime obscurant generation can be a key enabler of offensive maneuver of the Fleet despite the global proliferation of anti-ship cruise and ballistic missiles.

USS Mustin (DDG 89), USS Wayne E. Meyer (DDG 108) and USS Frank Cable (AS 40) test maritime obscurants south of Guam, June 25. (U.S. Navy/MC2 Timothy Wilson)