OFDM Numerology Design for 5G New Radio to Support IoT, eMBB, and MBSFN

5G New Radio (NR) access technology is envisioned to operate in sub-1 GHz to 100 GHz spectrum and support diverse use cases, including Internet-of-Things (IoT), Enhanced Mobile Broadband (eMBB), and Multimedia-Broadcast Single Frequency Network (MBSFN). NR is currently being standardized in the 3rd Generation Partnership Project (3GPP). In order to address diverse scenarios and deployments, a scalable CP-OFDM waveform has been approved in 3GPP as part of NR physical layer design for both uplink and downlink transmissions. The waveform is scalable in the sense that the sub-carrier spacing of OFDM can be chosen according to 15 × 2 n kHz, where n is an integer and 15 kHz is the subcarrier spacing used in Long Term Evolution (LTE). The choice of integer-valued parameter n depends on various factors, including type of deployments, service requirements, hardware impairments, mobility, performance and implementation complexity. This paper presents a comprehensive discussion of the factors involved in the design of NR OFDM numerology to support eMBB, IoT, and MBSFN.