On the Modeling of Inter-Sub-Symbol Interference in GFDM Transmission

Inter-sub-symbol interference (ISSI) refers to the interference that independently affects each group of sub-symbols transmitted on the same sub-carrier in generalized frequency division multiplexing (GFDM). In this letter, we derive a model to describe ISSI when transmission takes place over a frequency selective channel. The proposed model, which is derived by exploiting the discrete Gabor transform structure of GFDM, allows for the exact computation of the channel impulse response associated with each sub-carrier. Minimum mean-squared error and maximum likelihood receiver are considered as examples of the two different detection strategies based on the proposed modeling, together with the evaluation of their complexity. Simulation results demonstrate the improvement in the symbol error rate performance compared to another approach recently proposed in the literature that does not take into account the effect of ISSI.