Wavelet OFDM-Based Non-orthogonal Multiple Access Downlink Transceiver for Future Radio Access

Abstract

To address the exploding traffic demands for mobile data, non-orthogonal multiple access (NOMA) schemes for resource allocation are considered as one of the potential candidates for future radio access. To this date, NOMA is implemented via orthogonal frequency division multiplexing (OFDM) for waveform shaping, which employs redundancy in the form of cyclic prefix (CP) and induces peak-to-average power ratio (PAPR) problem. In this paper, wavelet OFDM (WOFDM) is proposed as a waveform shaping scheme for transceivers employing power domain NOMA for resource allocation. Since WOFDM-based systems do not use CP, they can reduce PAPR and increase spectral efficiency (SE). Link level performance of power domain NOMA with OFDM and WOFDM as waveform shaping techniques is evaluated in terms of PAPR, SE, and computational complexity (CC). In addition, power spectral densities of both transceivers are also analyzed. Simulation results show that NOMA with WOFDM outperforms NOMA with OFD in terms of PAPR reduction, out of band emissions reduction, SE, and CC.