Multiband and Photonically Amplified Fiber-Wireless Xhaul

Eduardo Saia Lima,Hugo Rodrigues Dias Filgueiras,Arismar Cerqueira Sodre,Luiz Augusto Melo Pereira,Antonio Marcos Alberti,Ramon Maia Borges

doi:10.1109/access.2020.2977562

Abstract

We propose and report the implementation of a multiband and photonically amplified fiber-wireless (FiWi) Xhaul based on radio over fiber (RoF) technology and four-wave mixing (FWM) nonlinear effect, aiming 5G applications. The proposed ultra-wideband approach enables to simultaneously transport and amplify multiple radiofrequency (RF) signals through optical links, which might be employed as backhaul, midhaul or fronthaul of cellular systems. The FWM effect, originated from the use of 35-m highly nonlinear fiber piece, gives rise to RF gain, when compared to conventional RoF (CRoF) systems. We demonstrate our technique allows replacing two conventional RF amplifiers with enhanced digital performance and/or significantly increasing the system throughput in 2.4 times, attaining 12 Gbit/s. Furthermore, a dual-band (7.5 and 28.0 GHz) wireless fronthaul, preceded by a 12.5-km optical midhaul, illustrates the multiband and photonically amplified FiWi Xhaul, by means of providing performance in terms of root mean square error vector magnitude (EVMRMS) in accordance to the 3GPP recommendations and at low phase noise level.

Highlights

International mobile telecommunications (IMT) for 2020 and beyond claims for a physical layer network review, as well as the use of innovative technical solutions to fulfill the generations scenarios and tough requirements
The baseband unit (BBU) pool can be directly connected to diverse remote radio unit (RRU), by using FH as a physical link, which is mostly based on single-mode fibers
The first photonics-assisted RF amplification (PAA) characterization step consisted on implementing a dual-band optical midhaul [31] with photonicsassisted RF gain, aiming to simultaneously transmit a modulated signal at 7.5 GHz and a continuous wave signal at 28.0 GHz in order to evaluate the digital performance in the lower frequency band in the presence of the higher frequency band

Summary

Introduction

International mobile telecommunications (IMT) for 2020 and beyond claims for a physical layer network review, as well as the use of innovative technical solutions to fulfill the generations scenarios and tough requirements. The novel photonic-assisted RF amplification technique characterization has been performed as a function of the system transmission parameters, including the two RF signals power levels, laser and pump optical power levels and DD-MZM bias voltages.

Results

Conclusion