Patent ID: 6944288

Claim:
A method of detecting double-talk and path changes in an echo cancellation system including a Least Mean Squares adaptive filter for generating an echo cancellation signal and having an echo path between a received path and a send path, and wherein a send path signal at an input to said send path comprises an echo source signal after said echo source signal has travelled said echo path and in the event that double-talk is present a double-talk signal, said method comprising: generating a cross correlation matrix R=E[ xx T ] where E is the statistical expectation operator and 𝕏 = [ X 0 X 1 ] ⁢ ⁢ where X 0 is said send path signal and X 1 is an estimated echo signal generated by said adaptive filter; and performing a matrix operation on said matrix R to generate a characteristic value determinative of the correlation between said signals X 0 and X 1 ; detecting the presence of double-talk and path changes occurring in said system from said characteristics value; and adjusting the operation of said adaptive filter in response to said detecting step.