Experimental Demonstration of Network Convergence with Coherent and AnalogRadio-over-Fibre signals For Densified 5.5G/6G Small Cell Networks

TL;DR

This paper demonstrates the coexistence of digital coherent and analogue radio over fibre signals in dense 5.5G/6G small cell networks, analyzing performance impacts of network components and establishing practical transmission limits.

Contribution

It provides the first experimental validation of coexistence feasibility for ARoF and coherent signals over real network infrastructure for future 6G deployments.

Findings

Coexistence is feasible with performance degradation as the number of ROADMs increases.

Performance limit is reached after 3 ROADMs and 49 km of fibre.

Trade-offs exist between spectral efficiency and network complexity.

Abstract

In this work we analyse and demonstrate the coexistence of digital coherent and analogue radio over fibre signals over an access-metro transmission network and field fibre. We analyse how the spectral proximity of the two signals and the non-ideal filter alignment of typical telecomms-grade ROADMs affect the signal performance. Our results show that coexistence is indeed possible, although performance deteriorates with the increase in number of ROADMs in the network topology. Thus, while todays access-metro networks will be able to support future 5.5 and 6G cell densification operating at mmWave and THz frequency, using spectral efficient analogue radio over fibre transmission, there will be trade-offs to be considered. In our experiment setup, we show that the limit for ARoF accessible performance is reached after transmission over 3 ROADMs and a total of 49 km of fibre.