Experimental Demonstration of a WDM-RoF Based Mobile Fronthaul With f-OFDM Signals by Using Directly Modulated 3s-DBR Laser

Future 5G mobile fronthaul (MFH) network will require high bandwidth and ultralow latency data transmission. Radio-over-fiber (RoF) technology is an efficient way to save bandwidth, which can significantly improve the radio signal transmission capacity over fiber. In this paper, we experimentally demonstrate a WDM-RoF based MFH with a directly modulated three-section distributed Bragg reflector (3s-DBR) laser. To transport the massive multiple-input-multiple-output radio signals, 12 channels of 211 MHz bandwidth filtered orthogonal frequency division multiplexing (f-OFDM) signals with 30 MHz guard-band are generated and transmission, using both 16 and 64-QAM, on different wavelength channels over 20 km standard single mode fiber is investigated. Experimental results show that all channels can meet the error vector magnitude requirements of 3GPP standard for the case of 16QAM; however, when moving to 64QAM, this is not guaranteed for all 12 channels due to signal degradation caused by the laser chirp and fiber dispersion.