Method and circuit for echo cancellation in a telecommunication system with non linear transmission paths

In fixed networks, echo cancellers and echo attenuators have proven effective for suppressing acoustic echoes and line echoes, namely when the echo signal and, for example, the input signal of a digital filter correlate. In networks using voice coding, such as mobile radio networks, to achieve comparable voice quality as in fixed networks, either echo compensation measures must be provided in the terminal, for example in the radiotelephone, or in the mobile network, if, as in many practical cases, echo cancellation in the radio telephone (1) is insufficient. According to the invention, the influence of the non-linearities produced by the encoder (11) and decoder (12) in the transmission channel is reproduced from existing signals (51, 52, bfi) in the transcoder unit (36) and with known components (33) of the non-linear telecommunication system, so that thereafter Known echo suppression measures can be taken.