Blind Separation for convolutive Mixtures of Non-stationary Signals Mitsuru KAWAMOTO 1 , Allan Kardec BARROS 1 , Ali MANSOUR , Kiyotoshi MATSUOKA 2 . and Noboru OHNISHI 1,3 l . Bio-Mimetic Control Research Center, RIKEN, 2271-130 Anagahora, Shimoshidnmi, Moriyamn-ku, Nagoya, 463. Japan 2. Department of Control Engineering, Kyushu Institute of Technology. 3. Graduate School of Engineering, Nagoya University Abstract-This paper proposes a method of ''blind separation'' which extracts non-stationary signals (e.g., speech signals, music) from their convolutive mixtures. The function is acquired by modifying a network's parameters so that a cost function takes the minimum at any time. the cost function is the one introduced by Matsuoka et al. The learning rule is derived from the natural gradient minimization of the cost function. The validity of the proposed method is confirmed by computer simulation.