5G NR RoF System Based on a Monolithically Integrated Multi-Wavelength Transmitter

We propose and demonstrate the use of a monolithically integrated multi-wavelength transmitter for multiband 5G new radio (NR) radio-over-fiber (RoF) systems, simultaneously operating in the standalone (SA) and non-standalone (NSA) modes. The novel integrated photonic circuit, integrating eight tunable and directly modulated distributed feedback lasers, aims to reduce the transmitter complexity and footprint, enabling compact, high-performance and low-cost 5G solutions for frequencies up to 10 GHz. We report the implementation of a 4G/5G shared optical mobile fronthaul using two 5G NR and a LTE-A signals, evaluated in two distinct scenarios, as a function of root mean square error vector magnitude (EVMRMS) and in accordance to the 3GPP Release 15 requirements. In the first phase, three optical carriers in C-band are independently modulated with three mentioned RF signals, whereas subcarrier multiplexing (SCM) is applied to the second scenario for jointly modulating an optical carrier at 1554 nm. Gbit/s throughput is demonstrated for validating the applicability of our monolithically integrated multi-wavelength transmitter either for enabling multiapplication and/or diverse RF standards, using a single wavelength or multiservice exploiting different wavelengths from an unique optical source.