Performance Analysis of 6G Communication Links in the Presence of Phase Noise

As the infrastructure of fifth generation (5G) is integrated worldwide, sixth generation (6G) of cellular communications standard is being developed as the next generation of high-speed wireless communications and internet connectivity. The goal of most innovations in communications is higher data rates and reduced latency. Thus, 6G is envisioned to operate on terahertz (THz) frequencies to leverage wide bandwidth of spectrum. Hardware operating at such high frequencies will be more susceptible to phase noise, or jitter in the time domain, because every time the frequency of the clock is upconverted, the phase noise increases. In addition, 6G will use higher-order modulation schemes to transmit data at higher speeds. It is unknown what modulations 6G communication systems will use, but 5G uses up to 256 QAM when connections are strong, thus we can assume 6G will possibly go even higher than that. Higher data rates require higher signal-to-noise ratios to reduce the bit error rate. Thus the higher the modulation order, the greater the impact of phase noise. The purpose of this paper is to further understand how 6G communication links will be impacted by phase noise. Simulation results demonstrate that there is a significant performance degradation due to phase noise when moving from 5G (Sub-6 GHz and millimeter Wave) to possible 6G carrier frequency ranges and adopting higher order modulation techniques.