Flexible multi-numerology systems for 5G new radio

The physical layer of 5G cellular communications systems is designed to achieve better flexibility in an effort to support diverse services and user requirements. Orthogonal frequency division multiplexing (OFDM) waveform parameters are enriched with flexible multi-numerology structures. This paper gives a short summary for the Third Generation Partnership Project (3GPP) New Radio (NR) standard and then describes the differences of building blocks for Long Term Evolution (LTE) systems and NR from the flexibility perspective. Research opportunities for multi-numerology systems are presented in a structured manner. Finally, inter-numerology interference (INI) and signal-to-interference ratio (SIR) results as a function of multi-numerology parameters, guard allocation and user power levels are obtained through computer simulations.