One of the challenging problenis in modern 'array processing IS Uie detection of the number of sources in unknown noise environments. This problem is not only of theoretical importance, but also of practical significance due to the fact that the environmental noise is, for many applications, non-white and of unknown covariance.Based on an assumption that the noise is correlated only over a limited spatial range, and by applying bi-may structure combined with canonical correlation analysis, a new, statistically solid, simple approach to solving the problem of detecting the number of signals in the n~ikriovl~r~ mise environment is presented in this papcr.