Uplink transceiver design for coded GFDMA systems

Abstract

In the generalized frequency division multiplexing (GFDM) technique, non-orthogonal pulse shapes are used to transmit data symbols on both time and frequency. This procedure causes self-interference among transmitted symbols. Recently, a modified version of GFDM, coded GFDM (CGFDM), has been introduced in which the transmitter matrix is unitary, avoiding the noise enhancement during self-interference cancellation. In this paper, we generalize the CGFDM for the multiuser uplink transmission scenario, and develop a zero-forcing (ZF) receiver to detect the data of multiple users. Simulation results show that the proposed ZF receiver outperforms the conventional ZF based generalized frequency division multiple access (GFDMA) receiver when the prototype filters are less localized and the number of subsymbols is high; however, with an increase in computational complexity. Moreover, a receiver with remarkably lower computational complexity is proposed based on the unitarity of the transmitter matrix in CGFDM and the assumption of relatively low frequency selectivity of the communication channels. This low-complexity receiver provides the same bit error rate (BER) performance of the ZF receiver in the low to mid range SNRs. (C) 2020 Elsevier B.V. All rights reserved.