Analysis of Phase Noise in a Hybrid Photonic/Millimetre-Wave System for Single and Multi-Carrier Radio Applications

Abstract

The future evolution of wireless networks, throughout the 5G era and beyond, will require the expansion and augmentation of millimetre-wave systems for both terrestrial and satellite communications. Photonic technologies offer a cost efficient and high bandwidth platform for millimetre-wave carrier generation and distribution, but can introduce high levels of phase noise through optical heterodyning, which is highly problematic for mobile signal waveforms. In this work, a detailed analytical model of a hybrid photonic/mm-wave system is developed and discussed. Through careful system design, the system is found to support both 5G compatible multi-carrier (OFDM) and single carrier (APSK) modulation at 60 GHz. APSK is found to offer higher tolerance mm-wave phase noise compared to OFDM, ultimately easing optical linewidth restrictions to ∼30 kHz. The model is extended to include a novel millimetre wave phase noise cancelling receiver, which is shown to significantly alleviate these restrictions even further—enabling phase noise free mm-wave operation for optical linewidths up to ∼2 MHz. Detailed analysis and discussion of this extended system lead to the establishment of a theoretical relationship between the mm-wave receiver design and the achievable system performance in terms of error vector magnitude (EVM). Excellent matching of the predicted theoretical with simulated performances is shown.