Method for predicting performance levels of a communication system over a transmission channel (CHNL), this system comprising: - a transmitter capable of applying to information bits, transmitted by a source, a bit-interleaved coded modulation so as to generate coded symbols, these coded symbols being transmitted by the transmitter over the transmission channel, this coded modulation being based on a turbo-code comprising at least two component codes (RSC1, RSC2); and - an iterative receiver capable of implementing an iterative interference cancellation technique for processing the coded symbols received from the transmission channel, this iterative receiver comprising an equalizer (LMMSE-IC), a demodulator (DEMOD) and a turbo-decoder (TURBO-DEC) activated on each iteration implemented by the iterative receiver, the turbo-decoder comprising at least two decoders (DEC1, DEC2) making it possible to respectively decode the component codes of the turbo-code, these decoders being capable of iteratively exchanging probabilistic quantities; the prediction method comprising, for each iteration; of the iterative receiver: - a first step of determination (E70-E130) of a value γ ̅ E q i representative of a signal-to-interference-plus-noise ratio at the output of the equalizer, from an estimation of the transmission channel and an estimation v̅ of the variance of the coded symbols at the input of the equalizer on the iteration i, this determination being made by using a pre-established function characterizing the behaviour of the equalizer; and - a second step of determination: ∘ of a probability of transmission error P e ( i) on the channel; ∘ of a variance v̅ i of the coded symbols at the output of the turbo-decoder; and ∘ of a mean mutual information I E, D E C i between the information bits transmitted by the source and probabilistic quantities representative of extrinsic probabilities on these information bits supplied at the output of the turbo-decoder; this determination being made from the value γ ̅ E q i and a so-called a priori mean mutual information I A, DEC i between the information bits transmitted by the source and probabilistic quantities representative of a priori probabilities on these information bits available at the input of the turbo-decoder on the iteration i, by using pre-established functions characterizing the behaviour of the demodulator and of the turbo-decoder for a predetermined number (NDEC) of decoding iterations implemented by the turbo-decoder, the variance v̅ i being used in the first determination step, on the next iteration i + 1 of the iterative receiver, to estimate the variance v̅ of the coded symbols at the input of the equalizer, and the mean mutual information I E, D E C i being used in the second determination step, on the iteration i + 1, as a priori mean mutual information I A, D E C i + 1. - a transmitter capable of applying to information bits, transmitted by a source, a bit-interleaved coded modulation so as to generate coded symbols, these coded symbols being transmitted by the transmitter over the transmission channel, this coded modulation being based on a turbo-code comprising at least two component codes (RSC1, RSC2); and - an iterative receiver capable of implementing an iterative interference cancellation technique for processing the coded symbols received from the transmission channel, this iterative receiver comprising an equalizer (LMMSE-IC), a demodulator (DEMOD) and a turbo-decoder (TURBO-DEC) activated on each iteration implemented by the iterative receiver, the turbo-decoder comprising at least two decoders (DEC1, DEC2) making it possible to respectively decode the component codes of the turbo-code, these decoders being capable of iteratively exchanging probabilistic quantities; - a first step of determination (E70-E130) of a value γ ̅ E q i representative of a signal-to-interference-plus-noise ratio at the output of the equalizer, from an estimation of the transmission channel and an estimation v̅ of the variance of the coded symbols at the input of the equalizer on the iteration i, this determination being made by using a pre-established function characterizing the behaviour of the equalizer; and - a second step of determination: ∘ of a probability of transmission error P e ( i) on the channel; ∘ of a variance v̅ i of the coded symbols at the output of the turbo-decoder; and ∘ of a mean mutual information I E, D E C i between the information bits transmitted by the source and probabilistic quantities representative of extrinsic probabilities on these information bits supplied at the output of the turbo-decoder; this determination being made from the value γ ̅ E q i and a so-called a priori mean mutual information I A, DEC i between the information bits transmitted by the source and probabilistic quantities representative of a priori probabilities on these information bits available at the input of the turbo-decoder on the iteration i, by using pre-established functions characterizing the behaviour of the demodulator and of the turbo-decoder for a predetermined number (NDEC) of decoding iterations implemented by the turbo-decoder, ∘ of a probability of transmission error P e ( i) on the channel; ∘ of a variance v̅ i of the coded symbols at the output of the turbo-decoder; and ∘ of a mean mutual information I E, D E C i between the information bits transmitted by the source and probabilistic quantities representative of extrinsic probabilities on these information bits supplied at the output of the turbo-decoder;