The invention provides a method for controlling errors using a hybrid ARQ scheme employing a simultaneous multiple copy mode (i.e. transmitting several copies of a cell in a single frame when re-transmission is requested) and adaptive forward error correction (FEC) in a wideband wireless ATM communication system. The error ratio of a forward channel is estimated using the state of a reverse channel and, on the basis of this estimation, an encoding ratio for the forward error correction is selected. FEC encoded data is then mapped or converged onto fixed length protocol data units (PDUs) of the wireless link layer for transmission, with the mapping/convergence adapting to changes in the selected FEC encoding ratio (see figures 5 and 6). Using stronger FEC for poorer channels reduces the number of re-transmissions required, whereas a lower level of FEC for good channels maximises the available bandwidth.
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