抄録
In blind source separation the number of the sensors is usually assumed to be equal to that of the sources. In this case an indeterminacy appears with which any linear transform of an estimated source signal can also be considered another estimation of the source signal. Moreover in the case that the number of the sensors is greater than that of the sources, another indeterminacy arises due to the redundancy of the sensors. Although these indeterminacies are often considered unsubstantial and have been eliminated without definite bases, an appropriate normalization of the separator is important to enhance the accuracy of the separation result, particularly in the case of convolutive mixture. This paper shows two principles for eliminating these indeterminacies: (i) minimal distortion principle and (ii) inverse minimal distortion principle.
