A method for transmitting digital information represented by a plurality of transmit bits u from a mobile terminal to a central baseband unit comprising the steps of - mapping at least one of the plurality of transmit bits u to at least one first symbol x based on a first mapping M 1 and transmitting the first symbol x via an access channel, and - receiving a radio signal x' representing the first symbol x at a base transceiver station, and - quantizing the received radio signal x' based on a codebook C thus obtaining at least one vector v of bits v b representing codeword bits c q,b of a codeword index c q of a codeword of the codebook C, and - mapping the vector v to a second symbol y based on a second mapping M 2 at the base transceiver station, and - transmitting the second symbol y via a forward channel to the central baseband unit, and - receiving and demapping a received second symbol y' based on a second demapping M 2 -1 at the central baseband unit to determine soft-information for each bit of a vector v' associated with the received second symbol y', and - in a dequantizer comprised in the central baseband unit determining a conditional probability for each possible codeword index c q based on the soft-information for each bit of the vector v' associated with the second symbol y ' in a multiplier block, and demodulating all dequantizer codewords by a first demapping M 1 -1 thereby providing bit probabilities of a bit u k conditioned on each of the dequantizer codewords Q 1 -1 (c q), and determining (165,166) soft information u' of the transmit bits u by combining the conditional probability for each possible codeword index c q with the conditioned bit probabilities of each bit u k' and - determining the transmit bits u based on the determined soft information of the transmit bits u in a decoder. - mapping at least one of the plurality of transmit bits u to at least one first symbol x based on a first mapping M 1 and transmitting the first symbol x via an access channel, and - receiving a radio signal x' representing the first symbol x at a base transceiver station, and - quantizing the received radio signal x' based on a codebook C thus obtaining at least one vector v of bits v b representing codeword bits c q,b of a codeword index c q of a codeword of the codebook C, and - mapping the vector v to a second symbol y based on a second mapping M 2 at the base transceiver station, and - transmitting the second symbol y via a forward channel to the central baseband unit, and - receiving and demapping a received second symbol y' based on a second demapping M 2 -1 at the central baseband unit to determine soft-information for each bit of a vector v' associated with the received second symbol y', and - in a dequantizer comprised in the central baseband unit determining a conditional probability for each possible codeword index c q based on the soft-information for each bit of the vector v' associated with the second symbol y ' in a multiplier block, and demodulating all dequantizer codewords by a first demapping M 1 -1 thereby providing bit probabilities of a bit u k conditioned on each of the dequantizer codewords Q 1 -1 (c q), and determining (165,166) soft information u' of the transmit bits u by combining the conditional probability for each possible codeword index c q with the conditioned bit probabilities of each bit u k' and - determining the transmit bits u based on the determined soft information of the transmit bits u in a decoder.