Optically powered FiWi system for B5G hybrid VLC/RF access networks

Abstract

This paper proposes the concept and reports the demonstrator of an optically powered fiber/wireless (FiWi) system based on a hybrid visible light communication (VLC) and RF access network for beyond 5G (B5G) indoor applications. The power-over-fiber (PoF) technology is properly applied to simultaneously energize two components from the remote site, namely: a radio-over-fiber (RoF) module, which contains a photodetector and an RF amplifier; a red laser from the VLC system. The proposed PoF system is composed of a 500 m conventional multimode optical fiber (MMF) with a 62.5 μm core diameter, which enables the transmission of up to 12 W optical power with a power transmission efficiency (PTE) of 14%. In the proof of concept, 8.1 W optical power is generated to feed the 5G system components. Regarding the communication setup, a 5G new radio (5G NR) signal is initially transported through a RoF fronthaul, composed of 10 km of single-mode fiber (SMF), followed by the hybrid VLC/RF access network. The performance investigation of the B5G communication system is based on an analysis of the root mean square error vector magnitude (EVMRMS) parameter. Experimental results indicate 1.2 Gbps throughput in the VLC link using a 200 MHz bandwidth and 64-quadrature amplitude modulation (64-QAM), resulting in approximately 4.02% of EVMRMS. Moreover, the RF link at 3.5 GHz provides 360 Mbps with an EVMRMS of 2.67%. Finally, a comparison between the PoF system and conventional power supply validates the proposed approach's applicability for B5G wireless communications.