A Phase-Adaptive Echo Canceller with Reduced Sensitivity to Power Variations

In a previous correspondence [1], we have studied an echo canceller (EC) compensating far-end echos affected by frequency offset. It has been shown that the sensitivity of the loop gain versus the power
P
of the echo and the power
S
of the signal, can be reduced by adoption of a normalized gain multiplied by the echo power. In this correspondence a novel and very simple algorithm is described that further reduces this sensitivity and yields an optimum phase loop gain proportional to
(S/ p)^{1/6}
.