Mobile Communications Beyond 52.6 GHz: Waveforms, Numerology, and Phase Noise Challenge

In this paper, the first considerations for the fifth generation (5G) New Radio physical layer evolution to support beyond 52.6 GHz communications are provided in terms of physical layer numerology and example link budget. In addition, the performance of orthogonal frequency division multiplexing (OFDM) and discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM)modulations with cyclic prefix is evaluated for beyond 52.6 GHz communications with special emphasis on the phase noise (PN) induced distortion. It is observed that DFT-s-OFDM is more robust against PN under Release 15 assumptions, namely regarding the supported phase tracking reference symbol (PTRS) designs, since it enables more effective PN mitigation directly in the time domain. To further reduce the PN effect, the PTRS design for DFT-s-OFDM is revised, and for the OFDM waveform a novel block PTRS structure is introduced, providing similar link performance as DFT-s-OFDM. With the proposed improvements in the PTRS design, we show that the PN can be effectively compensated to enable beyond 52.6GHz mobile communications.