A method for selecting transmission channels in a multi-channel communication system for use for data transmission: wherein data, s(k), are sent at a time, k, the data, s(k), are received, wherein r(k) denotes data which are received at the time k, and wherein a comparison between sent data and received data occurs according to the formula: r k = ∑ l = 0 L − 1 h l s k − l + n k wherein h... h(L-1) denotes a channel impulse response with length L and n(k) denotes noise signals at the receiver, characterized in that, a blind channel estimator is modified for receiving feedback from a decoder with a residual error for an estimated tap due to a usage of a time average instead of a true expectation, wherein an a-posteriori output of the decoder, L D (c), with c being a vector of coded bits, and channel taps estimated in a previous iteration of a turbo equalizer, I u h are used for cancelling the residual, wherein a P-th order moment computed for estimating an I-th tap of the channel, with P and I being natural numbers, is changed in such a way that the residual error created for the time average does not include the I-th tap itself and that a modified version of the P-th-order moment used in the blind channel estimator is given by ζ l q = 1 M ∑ m = 1 M r π m, q + l ∏ i = 1 i ≠ q P s ^ π m, i where M is a number of logic strings, namely a set of encoded bits with the XOR-conjunction of its elements always being zero for each arbitrary original data sequence, π is an index operator and ŝ is the vector of the estimated symbols computed from the decoder given by s ^ = tanh L D c 2 and the residual error u due to an approximate expectation over non-logic strings components is calculated according to the formula: u = ∑ i = 0 i ≠ l L h i 1 M ∑ m = 1 M s π m, q + l ∏ i = 1 i ≠ q P s ^ π m, i} ≈ 0 wherein the sum in the formula involves all the taps of the channel apart of the desired l -th tap, and the values of s are uncorrelated with the values of h. wherein data, s(k), are sent at a time, k, the data, s(k), are received, wherein r(k) denotes data which are received at the time k, and wherein a comparison between sent data and received data occurs according to the formula: r k = ∑ l = 0 L − 1 h l s k − l + n k wherein h... h(L-1) denotes a channel impulse response with length L and n(k) denotes noise signals at the receiver, characterized in that, a blind channel estimator is modified for receiving feedback from a decoder with a residual error for an estimated tap due to a usage of a time average instead of a true expectation, wherein an a-posteriori output of the decoder, L D (c), with c being a vector of coded bits, and channel taps estimated in a previous iteration of a turbo equalizer, I u h are used for cancelling the residual, wherein a P-th order moment computed for estimating an I-th tap of the channel, with P and I being natural numbers, is changed in such a way that the residual error created for the time average does not include the I-th tap itself and that a modified version of the P-th-order moment used in the blind channel estimator is given by ζ l q = 1 M ∑ m = 1 M r π m, q + l ∏ i = 1 i ≠ q P s ^ π m, i where M is a number of logic strings, namely a set of encoded bits with the XOR-conjunction of its elements always being zero for each arbitrary original data sequence, π is an index operator and ŝ is the vector of the estimated symbols computed from the decoder given by s ^ = tanh L D c 2 and the residual error u due to an approximate expectation over non-logic strings components is calculated according to the formula: u = ∑ i = 0 i ≠ l L h i 1 M ∑ m = 1 M s π m, q + l ∏ i = 1 i ≠ q P s ^ π m, i} ≈ 0 wherein the sum in the formula involves all the taps of the channel apart of the desired l -th tap, and the values of s are uncorrelated with the values of h.