Patent ID: 6201866
Filing Date: 2001-03-13
Classification: H04B,H04M

Abstract:
A method of reinitializing coefficients of an adaptive filter in an echo canceler, the adaptive filter adjusting said coefficients to match characteristics of an echo path, and applying said coefficients to samples of a received signal to generate an echo replica that is subtracted from a local input signal to create a residual signal for outgoing transmission, comprising the steps of:grouping said coefficients into a plurality of segments;storing a plurality of candidate values for each one of said segments;monitoring signal levels in said echo canceler to determine when reinitialization is necessary;testing said candidate values, when reinitialization is determined to be necessary, by assigning each one of said candidate values to all of the coefficients in the corresponding one of said segments;generating echo replicas and corresponding residual signals by using the candidate values thus assigned;selecting a best candidate value for each one of said segments by evaluating said residual signals; andassigning each selected best candidate value to all of the coefficients in the corresponding one of said segments.