Industry Perspective

Reports on industry interest in 5G non-orthogonal multiple access (NOMA)and discusses a study being conducted to test and measure its transmission/performance capabilities. As a pure physical layer signal processing technology, NOMA was briefly studied In Release 14 study of fifth generation New Radio (5G NR) [2], with the focus on grant-free uplink transmission for the massive machine type communication (mMTC) scenario. Grant-based uplink NOMA was not high priority since it is more about scheduler implementation without much need for standardization. MUST (multi-user superposition transmission) was not borrowed for 5G NR downlink because of massive multiple-input multiple-output (MIMO) setup for > 3GHz deployment where the further gain from NOMA is marginal. The study was terminated in October 2016 so that the Third Generation Partnership Project (3GPP) can focus on more basic functionalities of 5G NR in Release 15. Even though Release 15 NR networks are largely orthogonal- multiple-access-based, there is strong interest in NOMA from both industry and academia. NOMA study was restarted in Release 15 [3], and applicable scenarios were expanded to ultra-reliable low-latency communication (URLLC) and enhanced mobile broadband (eMBB) . More than 16 NOMA schemes at the transmitter were proposed by over 14 companies. The study is expected to be completed in December 2018, followed by a Work Item for the normative work to be finished in December 2019.