Generalized Frequency Division Multiplexing with Flexible Index Modulation Numerology

In this letter, generalized frequency division multiplexing (GFDM) is combined with index modulation (IM) exploiting the block-based structure of GFDM in an innovative way. The proposed GFDM-IM scheme uses flexible IM numerology to reduce out-of-band (OOB) emission and provides a novel multilayer system model to further benefit from the enhanced distance spectrum of IM. The proposed scheme adapts maximum likelihood successive interference cancellation based near-optimum detector to improve the error performance and reduce the computational complexity. It has been shown that the proposed GFDM-IM scheme achieves better error performance than classical and IM-based orthogonal frequency division multiplexing and GFDM schemes at the same spectral efficiency, and provides an interesting tradeoff among OOB emission, spectral efficiency, and latency.