Radial basis function assisted reduced complexity in-phase/quadrature-phase turbo equalisation of coded modulation schemes

A radial basis function (RBF) assisted reduced complexity in-phase/quadrature-phase (I/Q) turbo equalisation (TEQ) scheme is investigated in the context of trellis coded modulation (TCM), turbo TCM (TTCM), bit-interleaved coded modulation (BICM) and iteratively decoded BICM (BICM-ID). The proposed schemes are characterised in performance terms, when communicating over frequency selective Rayleigh fading channels. The RBF-I/Q-TEQ-TTCM achieved a similar performance to the full-complexity RBF-TEQ-TTCM, while attaining a complexity reduction factor of 36 in terms of the required additions/subtractions and a factor 9 in terms of the multiplications/divisions necessitated.