Patent ID: 8880395

Claim:
A method of processing signals with a signal processing device, comprising: receiving a plurality of time domain mixed signals in a signal processing device, each time domain mixed signal including a mixture of original source signals; performing a Fourier-related transform on each time domain mixed signal with the signal processing device to generate time-frequency domain mixed signals corresponding to the time domain mixed signals; and performing independent component analysis on the time-frequency domain mixed signals to generate at least one estimated source signal corresponding to at least one of the original source signals, wherein the independent component analysis is performed in conjunction with a direction constraint based on a known direction of an original source signal with respect to a sensor array that detected the time domain mixed signals, wherein performing the independent component analysis includes use of a cost function that includes both a function corresponding to unconstrained independent component analysis and a function corresponding to the direction constraint, wherein the direction constraint is chosen to make demixing filters of a demixing matrix have a flat spectral response, and wherein the independent component analysis uses a multivariate probability density function to preserve the alignment of frequency bins in the at least one estimated source signal.