Burst-by-burst adaptive turbo-coded radial basis function-assisted decision feedback equalization

The performance of the proposed radial basis function (RBF) assisted turbo- coded adaptive modulation scheme is characterized in a wideband channel sce nario. We commence by introducing the novel concept of the Jacobian RBF equ alizer, which is a reduced-complexity version of the conventional RBF equal izer. Specifically, the Jacobian logarithmic RBF equalizer generates its ou tput in the logarithmic domain and hence it can be used to provide soft out puts for the turbo-channel decoder. We propose using the average magnitude of the log-likelihood ratio (LLR) of the bits in the received transmission burst before channel decoding as the channel quality measure for controllin g the mode-switching regime of our adaptive scheme.