Joint impact of fibre dispersion and frequency chirp on MCF‐based radio‐over‐fibre mobile fronthaul

Abstract

Multicore fibre (MCF) has attracted considerable attention in mobile fronthaul networks as a promising solution to face the ever-increasing mobile traffic demand and to support network capacity scaling in a cost-effective manner. However, MCF-based systems suffer from the inter-core crosstalk (IC-XT) noise, which could incur severe performance degradation. In this study, we investigate for the first time, to our knowledge, the performance of an analogue radio-over-fibre mobile fronthaul link employing MCF under the joint impact of fibre dispersion and frequency chirp. Herein, the authors consider the radio frequency (RF) power fading induced by fibre dispersion and frequency chirp. In addition, the frequency-dependent IC-XT power fluctuations induced by dispersion and frequency chirp have been discussed. Closed-form equations for the carrier-to-noise ratio penalty due to power fading and IC-XT are derived. Moreover, new expressions for the average and variance of the crosstalk transfer function are obtained. Also, the analysis accounts for inter-core skew, laser relative intensity noise, shot noise and thermal noise. It has been shown that both the desired signal and IC-XT signals show the same behaviour in the presence of fibre dispersion and frequency chirp. Moreover, results show that RF power fading is the key issue.