Highly efficient 100 × 14 GHz WDM-RoF optical system with OFC generator for 5G mm-wave applications

Abstract An efficient WDM-RoF optical system is investigated and demonstrated, by utilizing two innovative optical frequency comb (OFC) generators with center wavelengths of 1,552 nm and 1,572 nm. The OFC generator is designed by utilizing two cascaded optical modulators. A sinusoidal RF signal is applied to drive both modulators, where a single optical frequency modulator (FM) is connected in series with a single optical lithium niobate Mach–Zehnder modulator (LiNb-MZM). The proposed OFC source can generate seven flat comb lasers with a constant spacing of 0.5 nm among lasers. Two OFC sources with center wavelengths of 1,552 nm and 1,572 nm are evaluated in WDM-RoF system. The proposed WDM-RoF system demonstrates an effective transmission of 14 signals with a carrier RF of 100 GHz over a maximum transmission distance of 130 km. The system can achieve a quality transmission at input data rate up to 12 Gb/s. Improving the transmission distance, number of channels and optical bandwidth confirm that the proposed WDM-RoF system can cater the 5G millimeter-wave applications.