A data processing system blind source separation of an overcomplete set of signals generally includes means for storing input from sensors in a mixed signal matrix X 200, noise in a noise matrix V 202, an estimate of the individual signals from the mixture of signals from the signal sources in a source signal estimate matrix S 204, and an estimate of environmental effects in a mixing matrix A 206, the matrices related by X=AS+V; generating an initial estimate of A 208; determining the number of, and associated lines of correlation of, each source from A, and representing the sources in the source signal estimate matrix S 210; jointly optimizing S and A in an iterative manner to generate an optimized source signal estimate matrix S 212 and a final estimated mixing matrix A; and restoring the separated source signals from the optimized source signal estimate matrix S 214.